prepare release 4.4.1

The psycopg dialect was only added in SQLAlchemy 2.0. To avoid loading
errors when SQLAlchemy 1.4 is installed together with psycopg3,
check that the dialect is really available.

.codespellrc

@@ -0,0 +1,7 @@
+# https://github.com/codespell-project/codespell
+
+[codespell]
+skip = ./man/nominatim.1,data,./docs/styles.css,lib-php,module,munin,osm2pgsql,./test,./settings/*.lua,./settings/*.yaml,./settings/**/*.yaml,./settings/icu-rules,./nominatim/tokenizer/token_analysis/config_variants.py
+# Need to be lowercase in the list
+# Unter = Unter den Linden (an example address)
+ignore-words-list = inout,unter

.github/ISSUE_TEMPLATE/report-problems-with-the-software.md

@@ -7,10 +7,13 @@ assignees: ''
 
 ---
 
-<!-- Note: if you are installing Nominatim through a docker image, you should report issues with the installation process with the docker repository first. -->
+<!-- Note: if you are installing Nominatim through a docker image, you should report issues with the installation process with the docker repository first.
+
+     Do not send screen shots! Copy any console output directly into the issue.
+ -->
 
 **Describe the bug**
-<!-- A clear and concise description of what the bug is. -->
+<!-- A clear and concise description of what the bug is.-->
 
 **To Reproduce**
 <!-- Please describe what you did to get to the issue. -->
@@ -25,12 +28,15 @@ assignees: ''
 - RAM: 
 - number of CPUs:
 - type and size of disks:
-- bare metal/AWS/other cloud service: 
 
 **Postgresql Configuration:**
 
 <!-- List any configuration items you changed in your postgresql configuration. -->
 
+**Nominatim Configuration:**
+
+<!-- List the contents of your customized `.env` file. -->
+
 **Additional context**
 
 <!-- Add any other context about the problem here. -->

.github/actions/build-nominatim/action.yml

@@ -1,10 +1,10 @@
 name: 'Build Nominatim'
 
 inputs:
-    ubuntu:
+    flavour:
         description: 'Version of Ubuntu to install on'
         required: false
-        default: '20'
+        default: 'ubuntu-20'
     cmake-args:
         description: 'Additional options to hand to cmake'
         required: false
@@ -23,17 +23,18 @@ runs:
             sudo rm -rf /opt/hostedtoolcache/go /opt/hostedtoolcache/CodeQL /usr/lib/jvm /usr/local/share/chromium /usr/local/lib/android
             df -h
           shell: bash
-        - name: Install prerequisites
+        - name: Install${{ matrix.flavour }} prerequisites
           run: |
-            sudo apt-get install -y -qq libboost-system-dev libboost-filesystem-dev libexpat1-dev zlib1g-dev libbz2-dev libpq-dev libproj-dev libicu-dev liblua${LUA_VERSION}-dev lua${LUA_VERSION}
-            if [ "x$UBUNTUVER" == "x18" ]; then
-                pip3 install python-dotenv psycopg2==2.7.7 jinja2==2.8 psutil==5.4.2 pyicu==2.9 osmium PyYAML==5.1 datrie
+            sudo apt-get install -y -qq libboost-system-dev libboost-filesystem-dev libexpat1-dev zlib1g-dev libbz2-dev libpq-dev libproj-dev libicu-dev liblua${LUA_VERSION}-dev lua${LUA_VERSION} lua-dkjson nlohmann-json3-dev libspatialite7 libsqlite3-mod-spatialite
+            if [ "$FLAVOUR" == "oldstuff" ]; then
+                pip3 install MarkupSafe==2.0.1 python-dotenv psycopg2==2.7.7 jinja2==2.8 psutil==5.4.2 pyicu==2.9 osmium PyYAML==5.1 sqlalchemy==1.4.31 datrie asyncpg aiosqlite
             else
                 sudo apt-get install -y -qq python3-icu python3-datrie python3-pyosmium python3-jinja2 python3-psutil python3-psycopg2 python3-dotenv python3-yaml
+                pip3 install sqlalchemy psycopg aiosqlite
             fi
           shell: bash
           env:
-            UBUNTUVER: ${{ inputs.ubuntu }}
+            FLAVOUR: ${{ inputs.flavour }}
             CMAKE_ARGS: ${{ inputs.cmake-args }}
             LUA_VERSION: ${{ inputs.lua }}
 

.github/workflows/ci-tests.yml

@@ -7,11 +7,11 @@ jobs:
         runs-on: ubuntu-latest
 
         steps:
-            - uses: actions/checkout@v3
+            - uses: actions/checkout@v4
               with:
                 submodules: true
 
-            - uses: actions/cache@v3
+            - uses: actions/cache@v4
               with:
                   path: |
                      data/country_osm_grid.sql.gz
@@ -27,7 +27,7 @@ jobs:
                   mv nominatim-src.tar.bz2 Nominatim
 
             - name: 'Upload Artifact'
-              uses: actions/upload-artifact@v3
+              uses: actions/upload-artifact@v4
               with:
                   name: full-source
                   path: nominatim-src.tar.bz2
@@ -37,47 +37,38 @@ jobs:
         needs: create-archive
         strategy:
             matrix:
-                ubuntu: [18, 20, 22]
+                flavour: [oldstuff, "ubuntu-20", "ubuntu-22"]
                 include:
-                    - ubuntu: 18
-                      postgresql: 9.6
-                      postgis: 2.5
-                      pytest: pytest
-                      php: 7.2
-                    - ubuntu: 20
+                    - flavour: oldstuff
+                      ubuntu: 20
+                      postgresql: '9.6'
+                      postgis: '2.5'
+                      lua: '5.1'
+                    - flavour: ubuntu-20
+                      ubuntu: 20
                       postgresql: 13
                       postgis: 3
-                      pytest: py.test-3
-                      php: 7.4
-                    - ubuntu: 22
+                      lua: '5.3'
+                    - flavour: ubuntu-22
+                      ubuntu: 22
                       postgresql: 15
                       postgis: 3
-                      pytest: py.test-3
-                      php: 8.1
+                      lua: '5.3'
 
         runs-on: ubuntu-${{ matrix.ubuntu }}.04
 
         steps:
-            - uses: actions/download-artifact@v3
+            - uses: actions/download-artifact@v4
               with:
                   name: full-source
 
             - name: Unpack Nominatim
               run: tar xf nominatim-src.tar.bz2
 
-            - name: Setup PHP
-              uses: shivammathur/setup-php@v2
+            - uses: actions/setup-python@v5
               with:
-                  php-version: ${{ matrix.php }}
-                  tools: phpunit:9, phpcs, composer
-                  ini-values: opcache.jit=disable
-              env:
-                  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-
-            - uses: actions/setup-python@v4
-              with:
-                python-version: 3.6
-              if: matrix.ubuntu == 18
+                python-version: 3.7
+              if: matrix.flavour == 'oldstuff'
 
             - uses: ./Nominatim/.github/actions/setup-postgresql
               with:
@@ -86,63 +77,69 @@ jobs:
 
             - uses: ./Nominatim/.github/actions/build-nominatim
               with:
-                  ubuntu: ${{ matrix.ubuntu }}
+                  flavour: ${{ matrix.flavour }}
+                  lua: ${{ matrix.lua }}
 
-            - name: Install test prerequsites
-              run: sudo apt-get install -y -qq python3-pytest python3-behave
-              if: matrix.ubuntu == 20
+            - name: Install test prerequsites (behave from apt)
+              run: sudo apt-get install -y -qq python3-behave
+              if: matrix.flavour == 'ubuntu-20'
 
-            - name: Install test prerequsites
-              run: pip3 install pylint pytest behave==1.2.6
-              if: ${{ (matrix.ubuntu == 18) || (matrix.ubuntu == 22) }}
+            - name: Install test prerequsites (behave from pip)
+              run: pip3 install behave==1.2.6
+              if: (matrix.flavour == 'oldstuff') || (matrix.flavour == 'ubuntu-22')
 
-            - name: Install test prerequsites
-              run: sudo apt-get install -y -qq python3-pytest
-              if: matrix.ubuntu == 22
+            - name: Install test prerequsites (from apt for Ununtu 2x)
+              run: sudo apt-get install -y -qq python3-pytest python3-pytest-asyncio uvicorn
+              if: matrix.flavour != 'oldstuff'
 
-            - name: Install latest pylint/mypy
-              run: pip3 install -U pylint mypy types-PyYAML types-jinja2 types-psycopg2 types-psutil types-requests typing-extensions
-              if: matrix.ubuntu == 22
+            - name: Install newer pytest-asyncio
+              run: pip3 install -U pytest-asyncio
+              if: matrix.flavour == 'ubuntu-20'
 
-            - name: PHP linting
-              run: phpcs --report-width=120 .
-              working-directory: Nominatim
-              if: matrix.ubuntu == 22
+            - name: Install test prerequsites (from pip for Ubuntu 18)
+              run: pip3 install pytest pytest-asyncio uvicorn
+              if: matrix.flavour == 'oldstuff'
+
+            - name: Install Python webservers
+              run: pip3 install falcon starlette asgi_lifespan
+
+            - name: Install latest pylint
+              run: pip3 install -U pylint
+              if: matrix.flavour == 'ubuntu-22'
 
             - name: Python linting
-              run: pylint nominatim
+              run: python3 -m pylint nominatim
               working-directory: Nominatim
-              if: matrix.ubuntu == 22
-
-            - name: Python static typechecking
-              run: mypy --strict nominatim
-              working-directory: Nominatim
-              if: matrix.ubuntu == 22
-
-
-            - name: PHP unit tests
-              run: phpunit ./
-              working-directory: Nominatim/test/php
-              if: ${{ (matrix.ubuntu == 20) || (matrix.ubuntu == 22) }}
+              if: matrix.flavour == 'ubuntu-22'
 
             - name: Python unit tests
-              run: $PYTEST test/python
+              run: python3 -m pytest test/python
               working-directory: Nominatim
-              env:
-                PYTEST: ${{ matrix.pytest }}
 
             - name: BDD tests
               run: |
-                  behave -DREMOVE_TEMPLATE=1 -DBUILDDIR=$GITHUB_WORKSPACE/build --format=progress3
+                  python3 -m behave -DREMOVE_TEMPLATE=1 -DBUILDDIR=$GITHUB_WORKSPACE/build --format=progress3
               working-directory: Nominatim/test/bdd
 
+            - name: Install mypy and typechecking info
+              run: pip3 install -U mypy osmium uvicorn types-PyYAML types-jinja2 types-psycopg2 types-psutil types-requests types-ujson types-Pygments typing-extensions
+              if: matrix.flavour != 'oldstuff'
+
+            - name: Python static typechecking
+              run: python3 -m mypy --strict nominatim
+              working-directory: Nominatim
+              if: matrix.flavour != 'oldstuff'
 
     legacy-test:
         needs: create-archive
         runs-on: ubuntu-20.04
 
+        strategy:
+            matrix:
+                postgresql: ["13", "16"]
+
         steps:
-            - uses: actions/download-artifact@v3
+            - uses: actions/download-artifact@v4
               with:
                   name: full-source
 
@@ -152,19 +149,20 @@ jobs:
             - name: Setup PHP
               uses: shivammathur/setup-php@v2
               with:
-                  php-version: 7.4
+                  php-version: '7.4'
 
             - uses: ./Nominatim/.github/actions/setup-postgresql
               with:
-                  postgresql-version: 13
+                  postgresql-version: ${{ matrix.postgresql }}
                   postgis-version: 3
 
             - name: Install Postgresql server dev
-              run: sudo apt-get install postgresql-server-dev-13
+              run: sudo apt-get install postgresql-server-dev-$PGVER
+              env:
+                PGVER: ${{ matrix.postgresql }}
 
             - uses: ./Nominatim/.github/actions/build-nominatim
               with:
-                  ubuntu: 20
                   cmake-args: -DBUILD_MODULE=on
 
             - name: Install test prerequsites
@@ -172,7 +170,54 @@ jobs:
 
             - name: BDD tests (legacy tokenizer)
               run: |
-                  behave -DREMOVE_TEMPLATE=1 -DBUILDDIR=$GITHUB_WORKSPACE/build -DTOKENIZER=legacy --format=progress3
+                  python3 -m behave -DREMOVE_TEMPLATE=1 -DBUILDDIR=$GITHUB_WORKSPACE/build -DAPI_ENGINE=php -DTOKENIZER=legacy --format=progress3
+              working-directory: Nominatim/test/bdd
+
+
+    php-test:
+        needs: create-archive
+        runs-on: ubuntu-22.04
+
+        steps:
+            - uses: actions/download-artifact@v4
+              with:
+                  name: full-source
+
+            - name: Unpack Nominatim
+              run: tar xf nominatim-src.tar.bz2
+
+            - uses: ./Nominatim/.github/actions/setup-postgresql
+              with:
+                  postgresql-version: 15
+                  postgis-version: 3
+
+            - name: Setup PHP
+              uses: shivammathur/setup-php@v2
+              with:
+                  php-version: 8.1
+                  tools: phpunit:9, phpcs, composer
+                  ini-values: opcache.jit=disable
+              env:
+                  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+            - name: PHP linting
+              run: phpcs --report-width=120 .
+              working-directory: Nominatim
+
+            - name: PHP unit tests
+              run: phpunit ./
+              working-directory: Nominatim/test/php
+
+            - uses: ./Nominatim/.github/actions/build-nominatim
+              with:
+                  flavour: 'ubuntu-22'
+
+            - name: Install test prerequsites
+              run: sudo apt-get install -y -qq python3-behave
+
+            - name: BDD tests (php)
+              run: |
+                  python3 -m behave -DREMOVE_TEMPLATE=1 -DBUILDDIR=$GITHUB_WORKSPACE/build -DAPI_ENGINE=php --format=progress3
               working-directory: Nominatim/test/bdd
 
 
@@ -182,20 +227,13 @@ jobs:
 
         strategy:
             matrix:
-                name: [Ubuntu-18, Ubuntu-20, Ubuntu-22]
+                name: [Ubuntu-20, Ubuntu-22]
                 include:
-                    - name: Ubuntu-18
-                      flavour: ubuntu
-                      image: "ubuntu:18.04"
-                      ubuntu: 18
-                      install_mode: install-nginx
                     - name: Ubuntu-20
-                      flavour: ubuntu
                       image: "ubuntu:20.04"
                       ubuntu: 20
                       install_mode: install-apache
                     - name: Ubuntu-22
-                      flavour: ubuntu
                       image: "ubuntu:22.04"
                       ubuntu: 22
                       install_mode: install-apache
@@ -218,14 +256,6 @@ jobs:
                   apt-get install -y git sudo wget
                   ln -snf /usr/share/zoneinfo/$CONTAINER_TIMEZONE /etc/localtime && echo $CONTAINER_TIMEZONE > /etc/timezone
               shell: bash
-              if: matrix.flavour == 'ubuntu'
-
-            - name: Prepare container (CentOS)
-              run: |
-                  dnf update -y
-                  dnf install -y sudo glibc-langpack-en
-              shell: bash
-              if: matrix.flavour == 'centos'
 
             - name: Setup import user
               run: |
@@ -237,7 +267,7 @@ jobs:
                 OS: ${{ matrix.name }}
                 INSTALL_MODE: ${{ matrix.install_mode }}
 
-            - uses: actions/download-artifact@v3
+            - uses: actions/download-artifact@v4
               with:
                   name: full-source
                   path: /home/nominatim
@@ -255,26 +285,25 @@ jobs:
             - name: Prepare import environment
               run: |
                   mv Nominatim/test/testdb/apidb-test-data.pbf test.pbf
+                  mv Nominatim/settings/flex-base.lua flex-base.lua
+                  mv Nominatim/settings/import-extratags.lua import-extratags.lua
+                  mv Nominatim/settings/taginfo.lua taginfo.lua
                   rm -rf Nominatim
                   mkdir data-env-reverse
               working-directory: /home/nominatim
 
-            - name: Prepare import environment (CentOS)
-              run: |
-                  sudo ln -s /usr/local/bin/nominatim /usr/bin/nominatim
-                  echo NOMINATIM_DATABASE_WEBUSER="apache" > nominatim-project/.env
-                  cp nominatim-project/.env data-env-reverse/.env
-              working-directory: /home/nominatim
-              if: matrix.flavour == 'centos'
-
             - name: Print version
               run: nominatim --version
               working-directory: /home/nominatim/nominatim-project
 
+            - name: Print taginfo
+              run: lua taginfo.lua
+              working-directory: /home/nominatim
+
             - name: Collect host OS information
               run: nominatim admin --collect-os-info
               working-directory: /home/nominatim/nominatim-project
-              
+
             - name: Import
               run: nominatim import --osm-file ../test.pbf
               working-directory: /home/nominatim/nominatim-project
@@ -294,7 +323,6 @@ jobs:
             - name: Prepare update (Ubuntu)
               run: apt-get install -y python3-pip
               shell: bash
-              if: matrix.flavour == 'ubuntu'
 
             - name: Run update
               run: |
@@ -320,3 +348,54 @@ jobs:
             - name: Clean up database (reverse-only import)
               run: nominatim refresh --postcodes --word-tokens
               working-directory: /home/nominatim/nominatim-project
+
+    install-no-superuser:
+      runs-on: ubuntu-latest
+      needs: create-archive
+
+      steps:
+          - uses: actions/download-artifact@v4
+            with:
+                name: full-source
+
+          - name: Unpack Nominatim
+            run: tar xf nominatim-src.tar.bz2
+
+          - uses: ./Nominatim/.github/actions/setup-postgresql
+            with:
+                postgresql-version: 16
+                postgis-version: 3
+
+          - uses: ./Nominatim/.github/actions/build-nominatim
+            with:
+                flavour: ubuntu-22
+                lua: 5.3
+
+          - name: Prepare import environment
+            run: |
+                mv Nominatim/test/testdb/apidb-test-data.pbf test.pbf
+                rm -rf Nominatim
+
+          - name: Prepare Database
+            run: |
+                nominatim import --prepare-database
+
+          - name: Create import user
+            run: |
+                sudo -u postgres createuser osm-import
+                psql -d nominatim -c "ALTER USER \"osm-import\" WITH PASSWORD 'osm-import'"
+                psql -d nominatim -c 'GRANT CREATE ON SCHEMA public TO "osm-import"'
+
+          - name: Run import
+            run: |
+                NOMINATIM_DATABASE_DSN="pgsql:host=127.0.0.1;dbname=nominatim;user=osm-import;password=osm-import" nominatim import --continue import-from-file --osm-file test.pbf
+
+          - name: Check full import
+            run: nominatim admin --check-database
+
+    codespell:
+      runs-on: ubuntu-latest
+      steps:
+          - uses: codespell-project/actions-codespell@v2
+            with:
+                only_warn: 1

.mypy.ini

@@ -1,9 +1,13 @@
 [mypy]
+plugins = sqlalchemy.ext.mypy.plugin
+
+[mypy-sanic_cors.*]
+ignore_missing_imports = True
 
 [mypy-icu.*]
 ignore_missing_imports = True
 
-[mypy-osmium.*]
+[mypy-asyncpg.*]
 ignore_missing_imports = True
 
 [mypy-datrie.*]
@@ -11,3 +15,9 @@ ignore_missing_imports = True
 
 [mypy-dotenv.*]
 ignore_missing_imports = True
+
+[mypy-falcon.*]
+ignore_missing_imports = True
+
+[mypy-geoalchemy2.*]
+ignore_missing_imports = True

.pylintrc

@@ -1,6 +1,6 @@
 [MASTER]
 
-extension-pkg-whitelist=osmium
+extension-pkg-whitelist=osmium,falcon
 ignored-modules=icu,datrie
 
 [MESSAGES CONTROL]
@@ -13,6 +13,6 @@ ignored-classes=NominatimArgs,closing
 # 'too-many-ancestors' is triggered already by deriving from UserDict
 # 'not-context-manager' disabled because it causes false positives once
 #   typed Python is enabled. See also https://github.com/PyCQA/pylint/issues/5273
-disable=too-few-public-methods,duplicate-code,too-many-ancestors,bad-option-value,no-self-use,not-context-manager,use-dict-literal
+disable=too-few-public-methods,duplicate-code,too-many-ancestors,bad-option-value,no-self-use,not-context-manager,use-dict-literal,chained-comparison,attribute-defined-outside-init
 
-good-names=i,x,y,m,fd,db,cc
+good-names=i,j,x,y,m,t,fd,db,cc,x1,x2,y1,y2,pt,k,v,nr

CMakeLists.txt

@@ -19,8 +19,8 @@ list(APPEND CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake")
 project(nominatim)
 
 set(NOMINATIM_VERSION_MAJOR 4)
-set(NOMINATIM_VERSION_MINOR 2)
-set(NOMINATIM_VERSION_PATCH 2)
+set(NOMINATIM_VERSION_MINOR 4)
+set(NOMINATIM_VERSION_PATCH 1)
 
 set(NOMINATIM_VERSION "${NOMINATIM_VERSION_MAJOR}.${NOMINATIM_VERSION_MINOR}.${NOMINATIM_VERSION_PATCH}")
 
@@ -73,7 +73,7 @@ endif()
 #-----------------------------------------------------------------------------
 
 if (BUILD_IMPORTER)
-    find_package(PythonInterp 3.6 REQUIRED)
+    find_package(PythonInterp 3.7 REQUIRED)
 endif()
 
 #-----------------------------------------------------------------------------
@@ -82,26 +82,17 @@ endif()
 
 # Setting PHP binary variable as to command line (prevailing) or auto detect
 
-if (BUILD_API OR BUILD_IMPORTER)
+if (BUILD_API)
     if (NOT PHP_BIN)
          find_program (PHP_BIN php)
     endif()
     # sanity check if PHP binary exists
     if (NOT EXISTS ${PHP_BIN})
-        message(FATAL_ERROR "PHP binary not found. Install php or provide location with -DPHP_BIN=/path/php ")
+        message(WARNING "PHP binary not found. Only Python frontend can be used.")
+        set(PHP_BIN "")
     else()
         message (STATUS "Using PHP binary " ${PHP_BIN})
     endif()
-    if (NOT PHPCGI_BIN)
-        find_program (PHPCGI_BIN php-cgi)
-    endif()
-    # sanity check if PHP binary exists
-    if (NOT EXISTS ${PHPCGI_BIN})
-        message(WARNING "php-cgi binary not found. nominatim tool will not provide query functions.")
-        set (PHPCGI_BIN "")
-    else()
-        message (STATUS "Using php-cgi binary " ${PHPCGI_BIN})
-    endif()
 endif()
 
 #-----------------------------------------------------------------------------
@@ -233,7 +224,18 @@ if (BUILD_IMPORTER)
     install(DIRECTORY nominatim
             DESTINATION ${NOMINATIM_LIBDIR}/lib-python
             FILES_MATCHING PATTERN "*.py"
+            PATTERN "paths.py" EXCLUDE
             PATTERN __pycache__ EXCLUDE)
+
+    if (EXISTS ${PHP_BIN})
+        configure_file(${PROJECT_SOURCE_DIR}/cmake/paths-py.tmpl paths-py.installed)
+    else()
+        configure_file(${PROJECT_SOURCE_DIR}/cmake/paths-py-no-php.tmpl paths-py.installed)
+    endif()
+    install(FILES ${PROJECT_BINARY_DIR}/paths-py.installed
+            DESTINATION ${NOMINATIM_LIBDIR}/lib-python/nominatim
+            RENAME paths.py)
+
     install(DIRECTORY lib-sql DESTINATION ${NOMINATIM_LIBDIR})
 
     install(FILES ${COUNTRY_GRID_FILE}
@@ -257,18 +259,13 @@ if (BUILD_MODULE)
             DESTINATION ${NOMINATIM_LIBDIR}/module)
 endif()
 
-if (BUILD_API)
+if (BUILD_API AND EXISTS ${PHP_BIN})
     install(DIRECTORY lib-php DESTINATION ${NOMINATIM_LIBDIR})
 endif()
 
 install(FILES settings/env.defaults
               settings/address-levels.json
               settings/phrase-settings.json
-              settings/import-admin.style
-              settings/import-street.style
-              settings/import-address.style
-              settings/import-full.style
-              settings/import-extratags.style
               settings/import-admin.lua
               settings/import-street.lua
               settings/import-address.lua

CONTRIBUTING.md

@@ -69,7 +69,7 @@ Before submitting a pull request make sure that the tests pass:
 
 Nominatim follows semantic versioning. Major releases are done for large changes
 that require (or at least strongly recommend) a reimport of the databases.
-Minor releases can usually be applied to exisiting databases Patch releases
+Minor releases can usually be applied to existing databases. Patch releases
 contain bug fixes only and are released from a separate branch where the
 relevant changes are cherry-picked from the master branch.
 

ChangeLog

@@ -1,3 +1,93 @@
+4.4.1
+ * fix geocodejson output: admin level output should only print boundaries
+ * updating: restrict invalidation of child objects on large street features
+ * restrict valid interpolation house numbers to 0-999999
+ * fix import error when SQLAlchemy 1.4 and psycopg3 are installed
+ * various typo fixes in the documentation
+
+4.4.0
+ * add export to SQLite database and SQLite support for the frontend
+ * switch to Python frontend as the default frontend
+ * update to osm2pgsql 1.11.0
+ * add support for new osm2pgsql middle table format
+ * simplify geometry for large polygon objects not used in addresses
+ * various performance tweaks for search in Python frontend
+ * fix regression in search with categories where it was confused with near
+   search
+ * partially roll back use of SQLAlchemy lambda statements due to bugs
+   in SQLAchemy
+ * fix handling of timezones for timestamps from the database
+ * fix handling of full address searches in connection with a viewbox
+ * fix postcode computation of highway areas
+ * fix handling of timeout errors for Python <= 3.10
+ * fix address computation for postcode areas
+ * fix variable shadowing in osm2pgsql flex script, causing bugs with LuaJIT
+ * make sure extratags are always null when empty
+ * reduce importance of places without wikipedia reference
+ * improve performance of word count computations
+ * drop support for wikipedia tags with full URLs
+ * replace get_addressdata() SQL implementation with a Python function
+ * improve display name for non-address features
+ * fix postcode validation for postcodes with country code
+   (thanks @pawel-wroniszewski)
+ * add possibility to run imports without superuser database rights
+   (thanks @robbe-haesendonck)
+ * new CLI command for cleaning deleted relations (thanks @lujoh)
+ * add check for database version in the CLI check command
+ * updates to import styles ignoring more unused objects
+ * various typo fixes (thanks @kumarUjjawal)
+
+4.3.2
+ * fix potential SQL injection issue for 'nominatim admin --collect-os-info'
+ * PHP frontend: fix on-the-fly lookup of postcode areas near boundaries
+ * Python frontend: improve handling of viewbox
+ * Python frontend: correct deployment instructions
+
+4.3.1
+ * reintroduce result rematching
+ * improve search of multi-part names
+ * fix accidentally switched meaning of --reverse-only and --search-only in
+   warm command
+
+4.3.0
+ * fix failing importance recalculation command
+ * fix merging of linked names into unnamed boundaries
+ * fix a number of corner cases with interpolation splitting resulting in
+   invalid geometries
+ * fix failure in website generation when password contains curly brackets
+ * fix broken use of ST_Project in PostGIS 3.4
+ * new NOMINATIM_SEARCH_WITHIN_COUNTRIES setting to restrict reverse lookups
+   to known countries (thanks @alfmarcua)
+ * allow negative OSM IDs (thanks @alfmarcua)
+ * disallow import of Tiger data in a frozen DB
+ * avoid UPDATE to change settings to be compatible with r/o DBs (thanks @t-tomek)
+ * update bundled osm2pgsql to 1.9.2
+ * reorganise osm2pgsql flex style and make it the default
+ * exclude names ending in :wikipedia from indexing
+ * no longer accept comma as a list separator in name tags
+ * process forward dependencies on update to catch updates in geometries
+   of ways and relations
+ * fix handling of isolated silent letters during transliteration
+ * no longer assign postcodes to large linear features like rivers
+ * introduce nominatim.paths module for finding data and libraries
+ * documentation layout changed to material theme
+ * new documentation section for library
+ * various smaller fixes to existing documentation
+   (thanks @woodpeck, @bloom256, @biswajit-k)
+ * updates to vagrant install scripts, drop support for Ubuntu 18
+   (thanks @n-timofeev)
+ * removed obsolete configuration variables from env.defaults
+ * add script for generating a taginfo description (thanks @biswajit-k)
+ * modernize Python code around BDD test and add testing of Python frontend
+ * lots of new BDD tests for API output
+
+4.2.3
+
+ * fix deletion handling for 'nominatim add-data'
+ * adapt place_force_delete() to new deletion handling
+ * flex style: avoid dropping of postcode areas
+ * fix update errors on address interpolation handling
+
 4.2.2
 
  * extend flex-style library to fully support all default styles
@@ -201,7 +291,7 @@
  * increase splitting for large geometries to improve indexing speed
  * remove deprecated get_magic_quotes_gpc() function
  * make sure that all postcodes have an entry in word and are thus searchable
- * remove use of ST_Covers in conjunction woth ST_Intersects,
+ * remove use of ST_Covers in conjunction with ST_Intersects,
    causes bad query planning and slow updates in Postgis3
  * update osm2pgsql
 
@@ -258,7 +348,7 @@
  * exclude postcode ranges separated by colon from centre point calculation
  * update osm2pgsql, better handling of imports without flatnode file
  * switch to more efficient algorithm for word set computation
- * use only boundries for country and state parts of addresses
+ * use only boundaries for country and state parts of addresses
  * improve updates of addresses with housenumbers and interpolations
  * remove country from place_addressline table and use country_code instead
  * optimise indexes on search_name partition tables
@@ -297,7 +387,7 @@
 
  * complete rewrite of reverse search algorithm
  * add new geojson and geocodejson output formats
- * add simple export script to exprot addresses to CSV
+ * add simple export script to export addresses to CSV
  * remove is_in terms from address computation
  * remove unused search_name_country tables
  * various smaller fixes to query parsing
@@ -362,7 +452,7 @@
  * move installation documentation into this repo
  * add self-documenting vagrant scripts
  * remove --create-website, recommend to use website directory in build
- * add accessor functions for URL parameters and improve erro checking
+ * add accessor functions for URL parameters and improve error checking
  * remove IP blocking and rate-limiting code
  * enable CI via travis
  * reformatting for more consistent coding style
@@ -373,7 +463,7 @@
  * update to refactored osm2pgsql which use libosmium based types
  * switch from osmosis to pyosmium for updates
  * be more strict when matching against special search terms
- * handle postcode entries with mutliple values correctly
+ * handle postcode entries with multiple values correctly
 
 2.5
 

SECURITY.md

@@ -9,11 +9,10 @@ versions.
 
 | Version | End of support for security updates |
 | ------- | ----------------------------------- |
+| 4.4.x   | 2026-03-07                          |
+| 4.3.x   | 2025-09-07                          |
 | 4.2.x   | 2024-11-24                          |
 | 4.1.x   | 2024-08-05                          |
-| 4.0.x   | 2023-11-02                          |
-| 3.7.x   | 2023-04-05                          |
-| 3.6.x   | 2022-12-12                          |
 
 ## Reporting a Vulnerability
 
@@ -37,4 +36,6 @@ incident. Announcements will also be published at the
 
 ## List of Previous Incidents
 
+* 2023-11-20 - [SQL injection vulnerability](https://nominatim.org/2023/11/20/release-432.html)
+* 2023-02-21 - [cross-site scripting vulnerability](https://nominatim.org/2023/02/21/release-421.html)
 * 2020-05-04 - [SQL injection issue on /details endpoint](https://lists.openstreetmap.org/pipermail/geocoding/2020-May/002012.html)

Vagrantfile

@@ -17,6 +17,14 @@ Vagrant.configure("2") do |config|
     checkout = "no"
   end
 
+  config.vm.provider "hyperv" do |hv, override|
+    hv.memory = 2048
+    hv.linked_clone = true
+    if ENV['CHECKOUT'] != 'y' then
+      override.vm.synced_folder ".", "/home/vagrant/Nominatim", type: "smb", smb_host: ENV['SMB_HOST'] || ENV['COMPUTERNAME']
+    end
+  end
+
   config.vm.provider "virtualbox" do |vb, override|
     vb.gui = false
     vb.memory = 2048
@@ -30,11 +38,38 @@ Vagrant.configure("2") do |config|
     lv.memory = 2048
     lv.nested = true
     if ENV['CHECKOUT'] != 'y' then
-      override.vm.synced_folder ".", "/home/vagrant/Nominatim", type: 'nfs'
+      override.vm.synced_folder ".", "/home/vagrant/Nominatim", type: 'nfs', nfs_udp: false
     end
   end
 
-  config.vm.define "ubuntu", primary: true do |sub|
+  config.vm.define "ubuntu22", primary: true do |sub|
+      sub.vm.box = "generic/ubuntu2204"
+      sub.vm.provision :shell do |s|
+        s.path = "vagrant/Install-on-Ubuntu-22.sh"
+        s.privileged = false
+        s.args = [checkout]
+      end
+  end
+
+  config.vm.define "ubuntu22-apache" do |sub|
+      sub.vm.box = "generic/ubuntu2204"
+      sub.vm.provision :shell do |s|
+        s.path = "vagrant/Install-on-Ubuntu-22.sh"
+        s.privileged = false
+        s.args = [checkout, "install-apache"]
+      end
+  end
+
+  config.vm.define "ubuntu22-nginx" do |sub|
+      sub.vm.box = "generic/ubuntu2204"
+      sub.vm.provision :shell do |s|
+        s.path = "vagrant/Install-on-Ubuntu-22.sh"
+        s.privileged = false
+        s.args = [checkout, "install-nginx"]
+      end
+  end
+
+  config.vm.define "ubuntu20" do |sub|
       sub.vm.box = "generic/ubuntu2004"
       sub.vm.provision :shell do |s|
         s.path = "vagrant/Install-on-Ubuntu-20.sh"
@@ -43,7 +78,7 @@ Vagrant.configure("2") do |config|
       end
   end
 
-  config.vm.define "ubuntu-apache" do |sub|
+  config.vm.define "ubuntu20-apache" do |sub|
       sub.vm.box = "generic/ubuntu2004"
       sub.vm.provision :shell do |s|
         s.path = "vagrant/Install-on-Ubuntu-20.sh"
@@ -52,7 +87,7 @@ Vagrant.configure("2") do |config|
       end
   end
 
-  config.vm.define "ubuntu-nginx" do |sub|
+  config.vm.define "ubuntu20-nginx" do |sub|
       sub.vm.box = "generic/ubuntu2004"
       sub.vm.provision :shell do |s|
         s.path = "vagrant/Install-on-Ubuntu-20.sh"
@@ -60,51 +95,4 @@ Vagrant.configure("2") do |config|
         s.args = [checkout, "install-nginx"]
       end
   end
-
-  config.vm.define "ubuntu18" do |sub|
-      sub.vm.box = "generic/ubuntu1804"
-      sub.vm.provision :shell do |s|
-        s.path = "vagrant/Install-on-Ubuntu-18.sh"
-        s.privileged = false
-        s.args = [checkout]
-      end
-  end
-
-  config.vm.define "ubuntu18-apache" do |sub|
-      sub.vm.box = "generic/ubuntu1804"
-      sub.vm.provision :shell do |s|
-        s.path = "vagrant/Install-on-Ubuntu-18.sh"
-        s.privileged = false
-        s.args = [checkout, "install-apache"]
-      end
-  end
-
-  config.vm.define "ubuntu18-nginx" do |sub|
-      sub.vm.box = "generic/ubuntu1804"
-      sub.vm.provision :shell do |s|
-        s.path = "vagrant/Install-on-Ubuntu-18.sh"
-        s.privileged = false
-        s.args = [checkout, "install-nginx"]
-      end
-  end
-
-  config.vm.define "centos7" do |sub|
-      sub.vm.box = "centos/7"
-      sub.vm.provision :shell do |s|
-        s.path = "vagrant/Install-on-Centos-7.sh"
-        s.privileged = false
-        s.args = [checkout]
-      end
-  end
-
-  config.vm.define "centos" do |sub|
-      sub.vm.box = "generic/centos8"
-      sub.vm.provision :shell do |s|
-        s.path = "vagrant/Install-on-Centos-8.sh"
-        s.privileged = false
-        s.args = [checkout]
-      end
-  end
-
-
 end

cmake/paths-py-no-php.tmpl

@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2022 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Path settings for extra data used by Nominatim (installed version).
+"""
+from pathlib import Path
+
+PHPLIB_DIR = None
+SQLLIB_DIR = (Path('@NOMINATIM_LIBDIR@') / 'lib-sql').resolve()
+DATA_DIR = Path('@NOMINATIM_DATADIR@').resolve()
+CONFIG_DIR = Path('@NOMINATIM_CONFIGDIR@').resolve()

cmake/paths-py.tmpl

@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2022 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Path settings for extra data used by Nominatim (installed version).
+"""
+from pathlib import Path
+
+PHPLIB_DIR = (Path('@NOMINATIM_LIBDIR@') / 'lib-php').resolve()
+SQLLIB_DIR = (Path('@NOMINATIM_LIBDIR@') / 'lib-sql').resolve()
+DATA_DIR = Path('@NOMINATIM_DATADIR@').resolve()
+CONFIG_DIR = Path('@NOMINATIM_CONFIGDIR@').resolve()

cmake/tool-installed.tmpl

@@ -4,17 +4,10 @@ import os
 
 sys.path.insert(1, '@NOMINATIM_LIBDIR@/lib-python')
 
-os.environ['NOMINATIM_NOMINATIM_TOOL'] = os.path.abspath(__file__)
-
 from nominatim import cli
 from nominatim import version
 
 version.GIT_COMMIT_HASH = '@GIT_HASH@'
 
 exit(cli.nominatim(module_dir='@NOMINATIM_LIBDIR@/module',
-                   osm2pgsql_path='@NOMINATIM_LIBDIR@/osm2pgsql',
-                   phplib_dir='@NOMINATIM_LIBDIR@/lib-php',
-                   sqllib_dir='@NOMINATIM_LIBDIR@/lib-sql',
-                   data_dir='@NOMINATIM_DATADIR@',
-                   config_dir='@NOMINATIM_CONFIGDIR@',
-                   phpcgi_path='@PHPCGI_BIN@'))
+                   osm2pgsql_path='@NOMINATIM_LIBDIR@/osm2pgsql'))

cmake/tool.tmpl

@@ -4,17 +4,10 @@ import os
 
 sys.path.insert(1, '@CMAKE_SOURCE_DIR@')
 
-os.environ['NOMINATIM_NOMINATIM_TOOL'] = os.path.abspath(__file__)
-
 from nominatim import cli
 from nominatim import version
 
 version.GIT_COMMIT_HASH = '@GIT_HASH@'
 
 exit(cli.nominatim(module_dir='@CMAKE_BINARY_DIR@/module',
-                   osm2pgsql_path='@CMAKE_BINARY_DIR@/osm2pgsql/osm2pgsql',
-                   phplib_dir='@CMAKE_SOURCE_DIR@/lib-php',
-                   sqllib_dir='@CMAKE_SOURCE_DIR@/lib-sql',
-                   data_dir='@CMAKE_SOURCE_DIR@/data',
-                   config_dir='@CMAKE_SOURCE_DIR@/settings',
-                   phpcgi_path='@PHPCGI_BIN@'))
+                   osm2pgsql_path='@CMAKE_BINARY_DIR@/osm2pgsql/osm2pgsql'))

docs/CMakeLists.txt

@@ -11,6 +11,7 @@ set (DOC_SOURCES
      develop
      api
      customize
+     library
      index.md
      extra.css
      styles.css
@@ -23,13 +24,12 @@ foreach (src ${DOC_SOURCES})
 endforeach()
 
 ADD_CUSTOM_TARGET(doc
-   COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/bash2md.sh ${PROJECT_SOURCE_DIR}/vagrant/Install-on-Ubuntu-18.sh ${CMAKE_CURRENT_BINARY_DIR}/appendix/Install-on-Ubuntu-18.md
    COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/bash2md.sh ${PROJECT_SOURCE_DIR}/vagrant/Install-on-Ubuntu-20.sh ${CMAKE_CURRENT_BINARY_DIR}/appendix/Install-on-Ubuntu-20.md
    COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/bash2md.sh ${PROJECT_SOURCE_DIR}/vagrant/Install-on-Ubuntu-22.sh ${CMAKE_CURRENT_BINARY_DIR}/appendix/Install-on-Ubuntu-22.md
-   COMMAND PYTHONPATH=${PROJECT_SOURCE_DIR} mkdocs build -d ${CMAKE_CURRENT_BINARY_DIR}/../site-html -f ${CMAKE_CURRENT_BINARY_DIR}/../mkdocs.yml
+   COMMAND mkdocs build -d ${CMAKE_CURRENT_BINARY_DIR}/../site-html -f ${CMAKE_CURRENT_BINARY_DIR}/../mkdocs.yml
 )
 
 ADD_CUSTOM_TARGET(serve-doc
-    COMMAND PYTHONPATH=${PROJECT_SOURCE_DIR} mkdocs serve
-    WORKING_DIRECTORY ${PROJECT_BINARY_DIR}
+    COMMAND mkdocs serve -f ${CMAKE_CURRENT_BINARY_DIR}/../mkdocs.yml
+    WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
 )

docs/admin/Advanced-Installations.md

@@ -5,6 +5,35 @@ your Nominatim database. It is assumed that you have already successfully
 installed the Nominatim software itself, if not return to the 
 [installation page](Installation.md).
 
+## Importing with a database user without superuser rights
+
+Nominatim usually creates its own PostgreSQL database at the beginning of the
+import process. This makes usage easier for the user but means that the
+database user doing the import needs the appropriate rights.
+
+If you prefer to run the import with a database user with limited rights,
+you can do so by changing the import process as follows:
+
+1. Run the command for database preparation with a database user with
+   superuser rights. For example, to use a db user 'dbadmin' for a
+   database 'nominatim', execute:
+
+   ```
+   NOMINATIM_DATABASE_DSN="pgsql:dbname=nominatim;user=dbadmin" nominatim import --prepare-database
+   ```
+
+2. Grant the import user the right to create tables. For example, foe user 'import-user':
+
+   ```
+   psql -d nominatim -c 'GRANT CREATE ON SCHEMA public TO "import-user"'
+   ```
+
+3. Now run the reminder of the import with the import user:
+
+   ```
+   NOMINATIM_DATABASE_DSN="pgsql:dbname=nominatim;user=import-user" nominatim import --continue import-from-file --osm-file file.pbf
+   ```
+
 ## Importing multiple regions (without updates)
 
 To import multiple regions in your database you can simply give multiple
@@ -36,16 +65,15 @@ which has the following structure:
 
 ```bash
 update
-    ├── europe
-    │   ├── andorra
-    │   │   └── sequence.state
-    │   └── monaco
-    │       └── sequence.state
-    └── tmp
-        └── europe
-                ├── andorra-latest.osm.pbf
-                └── monaco-latest.osm.pbf
-
+ ├── europe
+ │    ├── andorra
+ │    │    └── sequence.state
+ │    └── monaco
+ │         └── sequence.state
+ └── tmp
+      └── europe
+           ├── andorra-latest.osm.pbf
+           └── monaco-latest.osm.pbf
 
 ```
 
@@ -99,7 +127,7 @@ Change into the project directory and run the following command:
 
 This will get diffs from the replication server, import diffs and index
 the database. The default replication server in the
-script([Geofabrik](https://download.geofabrik.de)) provides daily updates.
+script ([Geofabrik](https://download.geofabrik.de)) provides daily updates.
 
 ## Using an external PostgreSQL database
 

docs/admin/Deployment-PHP.md

@@ -1,4 +1,4 @@
-# Deploying Nominatim
+# Deploying Nominatim using the PHP frontend
 
 The Nominatim API is implemented as a PHP application. The `website/` directory
 in the project directory contains the configured website. You can serve this
@@ -8,13 +8,13 @@ PHP scripts.
 This section gives a quick overview on how to configure Apache and Nginx to
 serve Nominatim. It is not meant as a full system administration guide on how
 to run a web service. Please refer to the documentation of
-[Apache](http://httpd.apache.org/docs/current/) and
+[Apache](https://httpd.apache.org/docs/current/) and
 [Nginx](https://nginx.org/en/docs/)
 for background information on configuring the services.
 
 !!! Note
-    Throughout this page, we assume that your Nominatim project directory is
-    located in `/srv/nominatim-project` and that you have installed Nominatim
+    Throughout this page, we assume your Nominatim project directory is
+    located in `/srv/nominatim-project` and you have installed Nominatim
     using the default installation prefix `/usr/local`. If you have put it
     somewhere else, you need to adjust the commands and configuration
     accordingly.

docs/admin/Deployment-Python.md

@@ -0,0 +1,140 @@
+# Deploying the Nominatim Python frontend
+
+The Nominatim can be run as a Python-based 
+[ASGI web application](https://asgi.readthedocs.io/en/latest/). You have the
+choice between [Falcon](https://falcon.readthedocs.io/en/stable/)
+and [Starlette](https://www.starlette.io/) as the ASGI framework.
+
+This section gives a quick overview on how to configure Nginx to serve
+Nominatim. Please refer to the documentation of
+[Nginx](https://nginx.org/en/docs/) for background information on how
+to configure it.
+
+!!! Note
+    Throughout this page, we assume your Nominatim project directory is
+    located in `/srv/nominatim-project` and you have installed Nominatim
+    using the default installation prefix `/usr/local`. If you have put it
+    somewhere else, you need to adjust the commands and configuration
+    accordingly.
+
+    We further assume that your web server runs as user `www-data`. Older
+    versions of CentOS may still use the user name `apache`. You also need
+    to adapt the instructions in this case.
+
+### Installing the required packages
+
+The recommended way to deploy a Python ASGI application is to run
+the ASGI runner [uvicorn](https://uvicorn.org/)
+together with [gunicorn](https://gunicorn.org/) HTTP server. We use
+Falcon here as the web framework.
+
+Create a virtual environment for the Python packages and install the necessary
+dependencies:
+
+``` sh
+sudo apt install virtualenv
+virtualenv /srv/nominatim-venv
+/srv/nominatim-venv/bin/pip install SQLAlchemy PyICU psycopg[binary] \
+   psycopg2-binary python-dotenv PyYAML falcon uvicorn gunicorn
+```
+
+### Setting up Nominatim as a systemd job
+
+Next you need to set up the service that runs the Nominatim frontend. This is
+easiest done with a systemd job.
+
+First you need to tell systemd to create a socket file to be used by
+hunicorn. Create the following file `/etc/systemd/system/nominatim.socket`:
+
+``` systemd
+[Unit]
+Description=Gunicorn socket for Nominatim
+
+[Socket]
+ListenStream=/run/nominatim.sock
+SocketUser=www-data
+
+[Install]
+WantedBy=multi-user.target
+```
+
+Now you can add the systemd service for Nominatim itself.
+Create the following file `/etc/systemd/system/nominatim.service`:
+
+``` systemd
+[Unit]
+Description=Nominatim running as a gunicorn application
+After=network.target
+Requires=nominatim.socket
+
+[Service]
+Type=simple
+Environment="PYTHONPATH=/usr/local/lib/nominatim/lib-python/"
+User=www-data
+Group=www-data
+WorkingDirectory=/srv/nominatim-project
+ExecStart=/srv/nominatim-venv/bin/gunicorn -b unix:/run/nominatim.sock -w 4 -k uvicorn.workers.UvicornWorker nominatim.server.falcon.server:run_wsgi
+ExecReload=/bin/kill -s HUP $MAINPID
+StandardOutput=append:/var/log/gunicorn-nominatim.log
+StandardError=inherit
+PrivateTmp=true
+TimeoutStopSec=5
+KillMode=mixed
+
+[Install]
+WantedBy=multi-user.target
+```
+
+This sets up gunicorn with 4 workers (`-w 4` in ExecStart). Each worker runs
+its own Python process using
+[`NOMINATIM_API_POOL_SIZE`](../customize/Settings.md#nominatim_api_pool_size)
+connections to the database to serve requests in parallel.
+
+Make the new services known to systemd and start it:
+
+``` sh
+sudo systemctl daemon-reload
+sudo systemctl enable nominatim.socket
+sudo systemctl start nominatim.socket
+sudo systemctl enable nominatim.service
+sudo systemctl start nominatim.service
+```
+
+This sets the service up, so that Nominatim is automatically started
+on reboot.
+
+### Configuring nginx
+
+To make the service available to the world, you need to proxy it through
+nginx. Add the following definition to the default configuration:
+
+``` nginx
+upstream nominatim_service {
+  server unix:/run/nominatim.sock fail_timeout=0;
+}
+
+server {
+    listen 80;
+    listen [::]:80;
+
+    root /var/www/html;
+    index /search;
+
+    location / {
+            proxy_set_header Host $http_host;
+            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+            proxy_set_header X-Forwarded-Proto $scheme;
+            proxy_redirect off;
+            proxy_pass http://nominatim_service;
+    }
+}
+```
+
+Reload nginx with
+
+```
+sudo systemctl reload nginx
+```
+
+and you should be able to see the status of your server under
+`http://localhost/status`.

docs/admin/Faq.md

@@ -37,40 +37,6 @@ nominatim import --continue indexing
 Otherwise it's best to start the full setup from the beginning.
 
 
-### PHP "open_basedir restriction in effect" warnings
-
-    PHP Warning:  file_get_contents(): open_basedir restriction in effect.
-
-You need to adjust the
-[open_basedir](https://www.php.net/manual/en/ini.core.php#ini.open-basedir)
-setting in your PHP configuration (`php.ini` file). By default this setting may
-look like this:
-
-    open_basedir = /srv/http/:/home/:/tmp/:/usr/share/pear/
-
-Either add reported directories to the list or disable this setting temporarily
-by adding ";" at the beginning of the line. Don't forget to enable this setting
-again once you are done with the PHP command line operations.
-
-
-### PHP timezeone warnings
-
-The Apache log may contain lots of PHP warnings like this:
-    `PHP Warning:  date_default_timezone_set() function.`
-
-You should set the default time zone as instructed in the warning in
-your `php.ini` file. Find the entry about timezone and set it to
-something like this:
-
-    ; Defines the default timezone used by the date functions
-    ; https://php.net/date.timezone
-    date.timezone = 'America/Denver'
-
-Or
-
-```
-echo "date.timezone = 'America/Denver'" > /etc/php.d/timezone.ini
-```
 
 ### nominatim.so version mismatch
 
@@ -170,7 +136,7 @@ recreate `nominatim.so`. Try
    cmake $main_Nominatim_path && make
 ```
 
-### Setup.php fails with "DB Error: extension not found"
+### Setup fails with "DB Error: extension not found"
 
 Make sure you have the PostgreSQL extensions "hstore" and "postgis" installed.
 See the installation instructions for a full list of required packages.

docs/admin/Import.md

@@ -14,15 +14,15 @@ to a single Nominatim setup: configuration, extra data, etc. Create a project
 directory apart from the Nominatim software and change into the directory:
 
 ```
-mkdir ~/nominatim-planet
-cd ~/nominatim-planet
+mkdir ~/nominatim-project
+cd ~/nominatim-project
 ```
 
 In the following, we refer to the project directory as `$PROJECT_DIR`. To be
 able to copy&paste instructions, you can export the appropriate variable:
 
 ```
-export PROJECT_DIR=~/nominatim-planet
+export PROJECT_DIR=~/nominatim-project
 ```
 
 The Nominatim tool assumes per default that the current working directory is
@@ -153,7 +153,7 @@ if you plan to use the installation only for exports to a
 [photon](https://photon.komoot.io/) database, then you can set up a database
 without search indexes. Add `--reverse-only` to your setup command above.
 
-This saves about 5% of disk space.
+This saves about 5% of disk space, import time won't be significant faster.
 
 ### Filtering Imported Data
 
@@ -228,7 +228,7 @@ to load the OSM data into the PostgreSQL database. This step is very demanding
 in terms of RAM usage. osm2pgsql and PostgreSQL are running in parallel at 
 this point. PostgreSQL blocks at least the part of RAM that has been configured
 with the `shared_buffers` parameter during
-[PostgreSQL tuning](Installation.md#postgresql-tuning)
+[PostgreSQL tuning](Installation.md#tuning-the-postgresql-database)
 and needs some memory on top of that. osm2pgsql needs at least 2GB of RAM for
 its internal data structures, potentially more when it has to process very large
 relations. In addition it needs to maintain a cache for node locations. The size
@@ -254,26 +254,71 @@ successfully.
 nominatim admin --check-database
 ```
 
-Now you can try out your installation by running:
+Now you can try out your installation by executing a simple query on the
+command line:
 
-```sh
+``` sh
+nominatim search --query Berlin
+```
+
+or, when you have a reverse-only installation:
+
+``` sh
+nominatim reverse --lat 51 --lon 45
+```
+
+If you want to run Nominatim as a service, you need to make a choice between
+running the modern Python frontend and the legacy PHP frontend.
+Make sure you have installed the right packages as per
+[Installation](Installation.md#software).
+
+#### Testing the Python frontend
+
+To run the test server against the Python frontend, you must choose a
+web framework to use, either starlette or falcon. Make sure the appropriate
+packages are installed. Then run
+
+``` sh
 nominatim serve
 ```
 
-This runs a small test server normally used for development. You can use it
-to verify that your installation is working. Go to
-`http://localhost:8088/status.php` and you should see the message `OK`.
-You can also run a search query, e.g. `http://localhost:8088/search.php?q=Berlin`.
+or, if you prefer to use Starlette instead of Falcon as webserver,
 
-Note that search query is not supported for reverse-only imports. You can run a
-reverse query, e.g. `http://localhost:8088/reverse.php?lat=27.1750090510034&lon=78.04209025`.
+``` sh
+nominatim serve --engine starlette
+```
 
-To run Nominatim via webservers like Apache or nginx, please read the
-[Deployment chapter](Deployment.md).
+Go to `http://localhost:8088/status.php` and you should see the message `OK`.
+You can also run a search query, e.g. `http://localhost:8088/search.php?q=Berlin`
+or, for reverse-only installations a reverse query,
+e.g. `http://localhost:8088/reverse.php?lat=27.1750090510034&lon=78.04209025`.
 
-## Adding search through category phrases
+Do not use this test server in production.
+To run Nominatim via webservers like Apache or nginx, please continue reading
+[Deploy the Python frontend](Deployment-Python.md).
 
-If you want to be able to search for places by their type through
+#### Testing the PHP frontend
+
+You can run a small test server with the PHP frontend like this:
+
+```sh
+nominatim serve --engine php
+```
+
+Go to `http://localhost:8088/status.php` and you should see the message `OK`.
+You can also run a search query, e.g. `http://localhost:8088/search.php?q=Berlin`
+or, for reverse-only installations a reverse query,
+e.g. `http://localhost:8088/reverse.php?lat=27.1750090510034&lon=78.04209025`.
+
+Do not use this test server in production.
+To run Nominatim via webservers like Apache or nginx, please continue reading
+[Deploy the PHP frontend](Deployment-PHP.md).
+
+
+
+## Enabling search by category phrases
+
+To be able to search for places by their type using
 [special phrases](https://wiki.openstreetmap.org/wiki/Nominatim/Special_Phrases)
 you also need to import these key phrases like this:
 

docs/admin/Installation.md

@@ -6,7 +6,6 @@ the following operating systems:
 
   * [Ubuntu 22.04](../appendix/Install-on-Ubuntu-22.md)
   * [Ubuntu 20.04](../appendix/Install-on-Ubuntu-20.md)
-  * [Ubuntu 18.04](../appendix/Install-on-Ubuntu-18.md)
 
 These OS-specific instructions can also be found in executable form
 in the `vagrant/` directory.
@@ -36,6 +35,7 @@ For compiling:
   * [bzip2](http://www.bzip.org/)
   * [zlib](https://www.zlib.net/)
   * [ICU](http://site.icu-project.org/)
+  * [nlohmann/json](https://json.nlohmann.me/)
   * [Boost libraries](https://www.boost.org/), including system and filesystem
   * PostgreSQL client libraries
   * a recent C++ compiler (gcc 5+ or Clang 3.8+)
@@ -44,23 +44,35 @@ For running Nominatim:
 
   * [PostgreSQL](https://www.postgresql.org) (9.6+ will work, 11+ strongly recommended)
   * [PostGIS](https://postgis.net) (2.2+ will work, 3.0+ strongly recommended)
-  * [Python 3](https://www.python.org/) (3.6+)
+  * [Python 3](https://www.python.org/) (3.7+)
   * [Psycopg2](https://www.psycopg.org) (2.7+)
   * [Python Dotenv](https://github.com/theskumar/python-dotenv)
   * [psutil](https://github.com/giampaolo/psutil)
   * [Jinja2](https://palletsprojects.com/p/jinja/)
+  * [SQLAlchemy](https://www.sqlalchemy.org/) (1.4.31+ with greenlet support)
+  * [asyncpg](https://magicstack.github.io/asyncpg) (0.8+)
   * [PyICU](https://pypi.org/project/PyICU/)
   * [PyYaml](https://pyyaml.org/) (5.1+)
   * [datrie](https://github.com/pytries/datrie)
-  * [PHP](https://php.net) (7.0 or later)
-  * PHP-pgsql
-  * PHP-intl (bundled with PHP)
-  * PHP-cgi (for running queries from the command line)
 
 For running continuous updates:
 
   * [pyosmium](https://osmcode.org/pyosmium/)
 
+For running the Python frontend:
+
+  * one of the following web frameworks:
+    * [falcon](https://falconframework.org/) (3.0+)
+    * [starlette](https://www.starlette.io/)
+  * [uvicorn](https://www.uvicorn.org/)
+
+For running the legacy PHP frontend:
+
+  * [PHP](https://php.net) (7.3+)
+  * PHP-pgsql
+  * PHP-intl (bundled with PHP)
+
+
 For dependencies for running tests and building documentation, see
 the [Development section](../develop/Development-Environment.md).
 
@@ -75,7 +87,7 @@ Take into account that the OSM database is growing fast.
 Fast disks are essential. Using NVME disks is recommended.
 
 Even on a well configured machine the import of a full planet takes
-around 2 days. On traditional spinning disks, 7-8 days are more realistic.
+around 2 days. When using traditional SSDs, 4-5 days are more realistic.
 
 ## Tuning the PostgreSQL database
 
@@ -107,15 +119,6 @@ you might consider setting:
 and even reduce `autovacuum_work_mem` further. This will reduce the amount
 of memory that autovacuum takes away from the import process.
 
-For the initial import, you should also set:
-
-    fsync = off
-    full_page_writes = off
-
-Don't forget to re-enable them after the initial import or you risk database
-corruption.
-
-
 ## Downloading and building Nominatim
 
 ### Downloading the latest release

docs/admin/Maintenance.md

@@ -60,16 +60,13 @@ to finish the recomputation.
 
 ## Removing large deleted objects
 
+Command: `nominatim admin --clean-deleted <PostgreSQL Time Interval>`
+
 Nominatim refuses to delete very large areas because often these deletions are
 accidental and are reverted within hours. Instead the deletions are logged in
 the `import_polygon_delete` table and left to the administrator to clean up.
 
-There is currently no command to do that. You can use the following SQL
-query to force a deletion on all objects that have been deleted more than
-a certain timespan ago (here: 1 month):
+To run this command you will need to pass a PostgreSQL time interval. For example to 
+delete any objects that have been deleted more than a month ago you would run:
+`nominatim admin --clean-deleted '1 month'`
 
-```sql
-SELECT place_force_delete(p.place_id) FROM import_polygon_delete d, placex p
-WHERE p.osm_type = d.osm_type and p.osm_id = d.osm_id
-      and age(p.indexed_date) > '1 month'::interval
-```

docs/admin/Migration.md

@@ -15,6 +15,25 @@ breaking changes. **Please read them before running the migration.**
     If you are migrating from a version <3.6, then you still have to follow
     the manual migration steps up to 3.6.
 
+## 4.2.0 -> 4.3.0
+
+### New indexes for reverse lookup
+
+The reverse lookup algorithm has changed slightly to improve performance.
+This change needs a different index in the database. The required index
+will be automatically build during migration. Until the new index is available
+performance of the /reverse endpoint is significantly reduced. You should
+therefore either remove traffic from the machine before attempting a
+version update or create the index manually **before** starting the update
+using the following SQL:
+
+```sql
+CREATE INDEX IF NOT EXISTS idx_placex_geometry_reverse_lookupPlaceNode
+  ON placex USING gist (ST_Buffer(geometry, reverse_place_diameter(rank_search)))
+  WHERE rank_address between 4 and 25 AND type != 'postcode'
+    AND name is not null AND linked_place_id is null AND osm_type = 'N';
+```
+
 ## 4.0.0 -> 4.1.0
 
 ### ICU tokenizer is the new default

docs/admin/Update.md

@@ -59,47 +59,6 @@ imported multiple country extracts and want to keep them
 up-to-date, [Advanced installations section](Advanced-Installations.md)
 contains instructions to set up and update multiple country extracts.
 
-#### Continuous updates
-
-This is the easiest mode. Simply run the replication command without any
-parameters:
-
-    nominatim replication
-
-The update application keeps running forever and retrieves and applies
-new updates from the server as they are published.
-
-You can run this command as a simple systemd service. Create a service
-description like that in `/etc/systemd/system/nominatim-updates.service`:
-
-```
-[Unit]
-Description=Continuous updates of Nominatim
-
-[Service]
-WorkingDirectory=/srv/nominatim
-ExecStart=nominatim replication
-StandardOutput=append:/var/log/nominatim-updates.log
-StandardError=append:/var/log/nominatim-updates.error.log
-User=nominatim
-Group=nominatim
-Type=simple
-
-[Install]
-WantedBy=multi-user.target
-```
-
-Replace the `WorkingDirectory` with your project directory. Also adapt user
-and group names as required.
-
-Now activate the service and start the updates:
-
-```
-sudo systemctl daemon-reload
-sudo systemctl enable nominatim-updates
-sudo systemctl start nominatim-updates
-```
-
 #### One-time mode
 
 When the `--once` parameter is given, then Nominatim will download exactly one
@@ -221,3 +180,53 @@ replication catch-up at whatever interval you desire.
     updated source with daily updates), use the
     continuous update mode. It ensures to re-request the newest update until it
     is published.
+
+
+#### Continuous updates
+
+!!! danger
+    This mode is no longer recommended to use and will removed in future
+    releases. systemd is much better
+    suited for running regular updates. Please refer to the setup
+    instructions for running one-time mode with systemd above.
+
+This is the easiest mode. Simply run the replication command without any
+parameters:
+
+    nominatim replication
+
+The update application keeps running forever and retrieves and applies
+new updates from the server as they are published.
+
+You can run this command as a simple systemd service. Create a service
+description like that in `/etc/systemd/system/nominatim-updates.service`:
+
+```
+[Unit]
+Description=Continuous updates of Nominatim
+
+[Service]
+WorkingDirectory=/srv/nominatim
+ExecStart=nominatim replication
+StandardOutput=append:/var/log/nominatim-updates.log
+StandardError=append:/var/log/nominatim-updates.error.log
+User=nominatim
+Group=nominatim
+Type=simple
+
+[Install]
+WantedBy=multi-user.target
+```
+
+Replace the `WorkingDirectory` with your project directory. Also adapt user
+and group names as required.
+
+Now activate the service and start the updates:
+
+```
+sudo systemctl daemon-reload
+sudo systemctl enable nominatim-updates
+sudo systemctl start nominatim-updates
+```
+
+

docs/api/Details.md

@@ -2,13 +2,17 @@
 
 Show all details about a single place saved in the database.
 
+This API endpoint is meant for visual inspection of the data in the database,
+mainly together with [Nominatim-UI](https://github.com/osm-search/nominatim-ui/).
+The parameters of the endpoint and the output may change occasionally between
+versions of Nominatim. Do not rely on the output in scripts or applications.
+
 !!! warning
-    The details page exists for debugging only. You may not use it in scripts
-    or to automatically query details about a result.
+    The details endpoint at https://nominatim.openstreetmap.org
+    may not used in scripts or bots at all.
     See [Nominatim Usage Policy](https://operations.osmfoundation.org/policies/nominatim/).
 
 
-## Parameters
 
 The details API supports the following two request formats:
 
@@ -35,59 +39,90 @@ for a place is different between Nominatim installation (servers) and
 changes when data gets reimported. Therefore it cannot be used as
 a permanent id and shouldn't be used in bug reports.
 
+!!! danger "Deprecation warning"
+    The API can also be used with the URL
+    `https://nominatim.openstreetmap.org/details.php`. This is now deprecated
+    and will be removed in future versions.
 
-Additional optional parameters are explained below.
+
+## Parameters
+
+This section lists additional optional parameters.
 
 ### Output format
 
-* `json_callback=<string>`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| json_callback | function name | _unset_ |
 
-Wrap JSON output in a callback function (JSONP) i.e. `<string>(<json>)`.
+When set, then JSON output will be wrapped in a callback function with
+the given name. See [JSONP](https://en.wikipedia.org/wiki/JSONP) for more
+information.
 
-* `pretty=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| pretty    | 0 or 1 | 0 |
 
-Add indentation to make it more human-readable. (Default: 0)
+`[PHP-only]` Add indentation to the output to make it more human-readable.
 
 
 ### Output details
 
-* `addressdetails=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| addressdetails | 0 or 1 | 0 |
 
-Include a breakdown of the address into elements. (Default: 0)
+When set to 1, include a breakdown of the address into elements.
 
-* `keywords=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| keywords  | 0 or 1 | 0 |
 
-Include a list of name keywords and address keywords (word ids). (Default: 0)
+When set to 1, include a list of name keywords and address keywords
+in the result.
 
-* `linkedplaces=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| linkedplaces  | 0 or 1 | 1 |
 
-Include a details of places that are linked with this one. Places get linked
+Include details of places that are linked with this one. Places get linked
 together when they are different forms of the same physical object. Nominatim
 links two kinds of objects together: place nodes get linked with the
 corresponding administrative boundaries. Waterway relations get linked together with their
 members.
-(Default: 1)
 
-* `hierarchy=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| hierarchy  | 0 or 1 | 0 |
 
-Include details of places lower in the address hierarchy. (Default: 0)
+Include details of places lower in the address hierarchy.
 
-* `group_hierarchy=[0|1]`
+`[Python-only]` will only return properly parented places. These are address
+or POI-like places that reuse the address of their parent street or place.
 
-For JSON output will group the places by type. (Default: 0)
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| group_hierarchy  | 0 or 1 | 0 |
 
-* `polygon_geojson=[0|1]`
+When set to 1, the output of the address hierarchy will be
+grouped by type.
 
-Include geometry of result. (Default: 0)
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| polygon_geojson | 0 or 1 | 0 |
+
+
+Include geometry of result.
 
 ### Language of results
 
-* `accept-language=<browser language string>`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| accept-language | browser language string | content of "Accept-Language" HTTP header |
 
-Preferred language order for showing result, overrides the value
-specified in the "Accept-Language" HTTP header.
-Either use a standard RFC2616 accept-language string or a simple
-comma-separated list of language codes.
+Preferred language order for showing search results. This may either be
+a simple comma-separated list of language codes or have the same format
+as the ["Accept-Language" HTTP header](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Language).
 
 
 ## Examples

docs/api/Lookup.md

@@ -3,7 +3,7 @@
 The lookup API allows to query the address and other details of one or
 multiple OSM objects like node, way or relation.
 
-## Parameters
+## Endpoint
 
 The lookup API has the following format:
 
@@ -15,75 +15,129 @@ The lookup API has the following format:
 prefixed with its type, one of node(N), way(W) or relation(R). Up to 50 ids
 can be queried at the same time.
 
-Additional optional parameters are explained below.
+!!! danger "Deprecation warning"
+    The API can also be used with the URL
+    `https://nominatim.openstreetmap.org/lookup.php`. This is now deprecated
+    and will be removed in future versions.
+
+
+## Parameters
+
+This section lists additional optional parameters.
 
 ### Output format
 
-* `format=[xml|json|jsonv2|geojson|geocodejson]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| format    | one of: `xml`, `json`, `jsonv2`, `geojson`, `geocodejson` | `jsonv2` |
 
-See [Place Output Formats](Output.md) for details on each format. (Default: xml)
+See [Place Output Formats](Output.md) for details on each format.
 
-* `json_callback=<string>`
 
-Wrap JSON output in a callback function (JSONP) i.e. `<string>(<json>)`.
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| json_callback | function name | _unset_ |
+
+When given, then JSON output will be wrapped in a callback function with
+the given name. See [JSONP](https://en.wikipedia.org/wiki/JSONP) for more
+information.
+
 Only has an effect for JSON output formats.
 
+
 ### Output details
 
-* `addressdetails=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| addressdetails | 0 or 1 | 0 |
 
-Include a breakdown of the address into elements. (Default: 0)
+When set to 1, include a breakdown of the address into elements.
+The exact content of the address breakdown depends on the output format.
+
+!!! tip
+    If you are interested in a stable classification of address categories
+    (suburb, city, state, etc), have a look at the `geocodejson` format.
+    All other formats return classifications according to OSM tagging.
+    There is a much larger set of categories and they are not always consistent,
+    which makes them very hard to work with.
 
 
-* `extratags=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| extratags | 0 or 1 | 0 |
 
-Include additional information in the result if available,
-e.g. wikipedia link, opening hours. (Default: 0)
+When set to 1, the response include any additional information in the result
+that is available in the database, e.g. wikipedia link, opening hours.
 
 
-* `namedetails=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| namedetails | 0 or 1 | 0 |
 
-Include a list of alternative names in the results. These may include
-language variants, references, operator and brand. (Default: 0)
+When set to 1, include a full list of names for the result. These may include
+language variants, older names, references and brand.
 
 
 ### Language of results
 
-* `accept-language=<browser language string>`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| accept-language | browser language string | content of "Accept-Language" HTTP header |
+
+Preferred language order for showing search results. This may either be
+a simple comma-separated list of language codes or have the same format
+as the ["Accept-Language" HTTP header](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Language).
+
+!!! tip
+    First-time users of Nominatim tend to be confused that they get different
+    results when using Nominatim in the browser versus in a command-line tool
+    like wget or curl. The command-line tools
+    usually don't send any Accept-Language header, prompting Nominatim
+    to show results in the local language. Browsers on the contratry always
+    send the currently chosen browser language.
 
-Preferred language order for showing search results, overrides the value
-specified in the "Accept-Language" HTTP header.
-Either use a standard RFC2616 accept-language string or a simple
-comma-separated list of language codes.
 
 ### Polygon output
 
-* `polygon_geojson=1`
-* `polygon_kml=1`
-* `polygon_svg=1`
-* `polygon_text=1`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| polygon_geojson | 0 or 1 | 0 |
+| polygon_kml     | 0 or 1 | 0 |
+| polygon_svg     | 0 or 1 | 0 |
+| polygon_text    | 0 or 1 | 0 |
 
-Output geometry of results as a GeoJSON, KML, SVG or WKT. Only one of these
-options can be used at a time. (Default: 0)
+Add the full geometry of the place to the result output. Output formats
+in GeoJSON, KML, SVG or WKT are supported. Only one of these
+options can be used at a time.
 
-* `polygon_threshold=0.0`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| polygon_threshold | floating-point number | 0.0 |
 
-Return a simplified version of the output geometry. The parameter is the
+When one of the polygon_* outputs is chosen, return a simplified version
+of the output geometry. The parameter describes the
 tolerance in degrees with which the geometry may differ from the original
-geometry. Topology is preserved in the result. (Default: 0.0)
+geometry. Topology is preserved in the geometry.
+
 
 ### Other
 
-* `email=<valid email address>`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| email     | valid email address | _unset_ |
 
 If you are making large numbers of request please include an appropriate email
-address to identify your requests. See Nominatim's [Usage Policy](https://operations.osmfoundation.org/policies/nominatim/) for more details.
+address to identify your requests. See Nominatim's
+[Usage Policy](https://operations.osmfoundation.org/policies/nominatim/) for more details.
 
-* `debug=[0|1]`
+
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| debug     | 0 or 1 | 0       |
 
 Output assorted developer debug information. Data on internals of Nominatim's
-"Search Loop" logic, and SQL queries. The output is (rough) HTML format.
-This overrides the specified machine readable format. (Default: 0)
+"search loop" logic, and SQL queries. The output is HTML format.
+This overrides the specified machine readable format.
 
 
 ## Examples

docs/api/Overview.md

@@ -1,8 +1,16 @@
 ### Nominatim API
 
-Nominatim indexes named (or numbered) features within the OpenStreetMap (OSM) dataset and a subset of other unnamed features (pubs, hotels, churches, etc).
+!!! Attention
+    The current version of Nominatim implements two different search frontends:
+    the old PHP frontend and the new Python frontend. They have a very similar
+    API but differ in some implementation details. These are marked in the
+    documentation as `[Python-only]` or `[PHP-only]`.
 
-Its API has the following endpoints for querying the data:
+    `https://nominatim.openstreetmap.org` implements the **Python frontend**.
+    So users should refer to the **`[Python-only]`** comments.
+
+This section describes the API V1 of the Nominatim web service. The
+service offers the following endpoints:
 
  * __[/search](Search.md)__ - search OSM objects by name or type
  * __[/reverse](Reverse.md)__ - search OSM object by their location
@@ -12,3 +20,6 @@ Its API has the following endpoints for querying the data:
                     back in Nominatim in case the deletion was accidental
  * __/polygons__ - list of broken polygons detected by Nominatim
  * __[/details](Details.md)__ - show internal details for an object (for debugging only)
+
+
+

docs/api/Reverse.md

@@ -1,6 +1,7 @@
 # Reverse Geocoding
 
-Reverse geocoding generates an address from a latitude and longitude.
+Reverse geocoding generates an address from a coordinate given as
+latitude and longitude.
 
 ## How it works
 
@@ -18,8 +19,7 @@ The other issue to be aware of is that the closest OSM object may not always
 have a similar enough address to the coordinate you were requesting. For
 example, in dense city areas it may belong to a completely different street.
 
-
-## Parameters
+## Endpoint
 
 The main format of the reverse API is
 
@@ -31,57 +31,101 @@ where `lat` and `lon` are latitude and longitude of a coordinate in WGS84
 projection. The API returns exactly one result or an error when the coordinate
 is in an area with no OSM data coverage.
 
-Additional parameters are accepted as listed below.
 
-!!! warning "Deprecation warning"
+!!! danger "Deprecation warning"
     The reverse API used to allow address lookup for a single OSM object by
-    its OSM id. This use is now deprecated. Use the [Address Lookup API](Lookup.md)
-    instead.
+    its OSM id for `[PHP-only]`. The use is considered deprecated.
+    Use the [Address Lookup API](Lookup.md) instead.
+
+!!! danger "Deprecation warning"
+    The API can also be used with the URL
+    `https://nominatim.openstreetmap.org/reverse.php`. This is now deprecated
+    and will be removed in future versions.
+
+
+## Parameters
+
+This section lists additional parameters to further influence the output.
 
 ### Output format
 
-* `format=[xml|json|jsonv2|geojson|geocodejson]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| format    | one of: `xml`, `json`, `jsonv2`, `geojson`, `geocodejson` | `xml` |
 
-See [Place Output Formats](Output.md) for details on each format. (Default: xml)
+See [Place Output Formats](Output.md) for details on each format.
 
-* `json_callback=<string>`
 
-Wrap JSON output in a callback function ([JSONP](https://en.wikipedia.org/wiki/JSONP)) i.e. `<string>(<json>)`.
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| json_callback | function name | _unset_ |
+
+When given, then JSON output will be wrapped in a callback function with
+the given name. See [JSONP](https://en.wikipedia.org/wiki/JSONP) for more
+information.
+
 Only has an effect for JSON output formats.
 
+
 ### Output details
 
-* `addressdetails=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| addressdetails | 0 or 1 | 1 |
 
-Include a breakdown of the address into elements. (Default: 1)
+When set to 1, include a breakdown of the address into elements.
+The exact content of the address breakdown depends on the output format.
+
+!!! tip
+    If you are interested in a stable classification of address categories
+    (suburb, city, state, etc), have a look at the `geocodejson` format.
+    All other formats return classifications according to OSM tagging.
+    There is a much larger set of categories and they are not always consistent,
+    which makes them very hard to work with.
 
 
-* `extratags=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| extratags | 0 or 1 | 0 |
 
-Include additional information in the result if available,
-e.g. wikipedia link, opening hours. (Default: 0)
+When set to 1, the response include any additional information in the result
+that is available in the database, e.g. wikipedia link, opening hours.
 
 
-* `namedetails=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| namedetails | 0 or 1 | 0 |
 
-Include a list of alternative names in the results. These may include
-language variants, references, operator and brand. (Default: 0)
+When set to 1, include a full list of names for the result. These may include
+language variants, older names, references and brand.
 
 
 ### Language of results
 
-* `accept-language=<browser language string>`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| accept-language | browser language string | content of "Accept-Language" HTTP header |
 
-Preferred language order for showing search results, overrides the value
-specified in the "Accept-Language" HTTP header.
-Either use a standard RFC2616 accept-language string or a simple
-comma-separated list of language codes.
+Preferred language order for showing search results. This may either be
+a simple comma-separated list of language codes or have the same format
+as the ["Accept-Language" HTTP header](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Language).
 
-### Result limitation
+!!! tip
+    First-time users of Nominatim tend to be confused that they get different
+    results when using Nominatim in the browser versus in a command-line tool
+    like wget or curl. The command-line tools
+    usually don't send any Accept-Language header, prompting Nominatim
+    to show results in the local language. Browsers on the contratry always
+    send the currently chosen browser language.
 
-* `zoom=[0-18]`
 
-Level of detail required for the address. Default: 18. This is a number that
+### Result restriction
+
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| zoom      | 0-18  | 18      |
+
+Level of detail required for the address. This is a number that
 corresponds roughly to the zoom level used in XYZ tile sources in frameworks
 like Leaflet.js, Openlayers etc.
 In terms of address details the zoom levels are as follows:
@@ -92,41 +136,81 @@ In terms of address details the zoom levels are as follows:
   5   | state
   8   | county
   10  | city
-  14  | suburb
+  12  | town / borough
+  13  | village / suburb
+  14  | neighbourhood
+  15  | any settlement
   16  | major streets
   17  | major and minor streets
   18  | building
 
 
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| layer     | comma-separated list of: `address`, `poi`, `railway`, `natural`, `manmade` | _unset_ (no restriction) |
+
+**`[Python-only]`**
+
+The layer filter allows to select places by themes.
+
+The `address` layer contains all places that make up an address:
+address points with house numbers, streets, inhabited places (suburbs, villages,
+cities, states etc.) and administrative boundaries.
+
+The `poi` layer selects all point of interest. This includes classic points
+of interest like restaurants, shops, hotels but also less obvious features
+like recycling bins, guideposts or benches.
+
+The `railway` layer includes railway infrastructure like tracks.
+Note that in Nominatim's standard configuration, only very few railway
+features are imported into the database.
+
+The `natural` layer collects features like rivers, lakes and mountains while
+the `manmade` layer functions as a catch-all for features not covered by the
+other layers.
+
+
 ### Polygon output
 
-* `polygon_geojson=1`
-* `polygon_kml=1`
-* `polygon_svg=1`
-* `polygon_text=1`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| polygon_geojson | 0 or 1 | 0 |
+| polygon_kml     | 0 or 1 | 0 |
+| polygon_svg     | 0 or 1 | 0 |
+| polygon_text    | 0 or 1 | 0 |
 
-Output geometry of results as a GeoJSON, KML, SVG or WKT. Only one of these
-options can be used at a time. (Default: 0)
+Add the full geometry of the place to the result output. Output formats
+in GeoJSON, KML, SVG or WKT are supported. Only one of these
+options can be used at a time.
 
-* `polygon_threshold=0.0`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| polygon_threshold | floating-point number | 0.0 |
 
-Return a simplified version of the output geometry. The parameter is the
+When one of the polygon_* outputs is chosen, return a simplified version
+of the output geometry. The parameter describes the
 tolerance in degrees with which the geometry may differ from the original
-geometry. Topology is preserved in the result. (Default: 0.0)
+geometry. Topology is preserved in the geometry.
+
 
 ### Other
 
-* `email=<valid email address>`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| email     | valid email address | _unset_ |
 
-If you are making a large number of requests, please include an appropriate email
-address to identify your requests. See Nominatim's [Usage Policy](https://operations.osmfoundation.org/policies/nominatim/) for more details.
+If you are making large numbers of request please include an appropriate email
+address to identify your requests. See Nominatim's
+[Usage Policy](https://operations.osmfoundation.org/policies/nominatim/) for more details.
 
 
-* `debug=[0|1]`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| debug     | 0 or 1 | 0       |
 
 Output assorted developer debug information. Data on internals of Nominatim's
-"Search Loop" logic, and SQL queries. The output is (rough) HTML format.
-This overrides the specified machine readable format. (Default: 0)
+"search loop" logic, and SQL queries. The output is HTML format.
+This overrides the specified machine readable format.
 
 
 ## Examples

docs/api/Search.md

@@ -8,12 +8,12 @@ The search query may also contain
 which are translated into specific OpenStreetMap (OSM) tags (e.g. Pub => `amenity=pub`).
 This can be used to narrow down the kind of objects to be returned.
 
-!!! warning
+!!! note
     Special phrases are not suitable to query all objects of a certain type in an
     area. Nominatim will always just return a collection of the best matches. To
     download OSM data by object type, use the [Overpass API](https://overpass-api.de/).
 
-## Parameters
+## Endpoint
 
 The search API has the following format:
 
@@ -21,35 +21,62 @@ The search API has the following format:
    https://nominatim.openstreetmap.org/search?<params>
 ```
 
-The search term may be specified with two different sets of parameters:
+!!! danger "Deprecation warning"
+    The API can also be used with the URL
+    `https://nominatim.openstreetmap.org/search.php`. This is now deprecated
+    and will be removed in future versions.
 
-* `q=<query>`
+The query term can be given in two different forms: free-form or structured.
 
-    Free-form query string to search for.
-    Free-form queries are processed first left-to-right and then right-to-left if that fails. So you may search for
-    [pilkington avenue, birmingham](https://nominatim.openstreetmap.org/search?q=pilkington+avenue,birmingham) as well as for
-    [birmingham, pilkington avenue](https://nominatim.openstreetmap.org/search?q=birmingham,+pilkington+avenue).
-    Commas are optional, but improve performance by reducing the complexity of the search.
+### Free-form query
 
+| Parameter | Value |
+|-----------| ----- |
+| q         | Free-form query string to search for |
 
-* `street=<housenumber> <streetname>`
-* `city=<city>`
-* `county=<county>`
-* `state=<state>`
-* `country=<country>`
-* `postalcode=<postalcode>`
+In this form, the query can be unstructured.
+Free-form queries are processed first left-to-right and then right-to-left if that fails. So you may search for
+[pilkington avenue, birmingham](https://nominatim.openstreetmap.org/search?q=pilkington+avenue,birmingham) as well as for
+[birmingham, pilkington avenue](https://nominatim.openstreetmap.org/search?q=birmingham,+pilkington+avenue).
+Commas are optional, but improve performance by reducing the complexity of the search.
 
-    Alternative query string format split into several parameters for structured requests.
-    Structured requests are faster but are less robust against alternative
-    OSM tagging schemas. **Do not combine with** `q=<query>` **parameter**.
+The free-form may also contain special phrases to describe the type of
+place to be returned or a coordinate to search close to a position.
 
-Both query forms accept the additional parameters listed below.
+### Structured query
+
+| Parameter  | Value |
+|----------- | ----- |
+| amenity    | name and/or type of POI |
+| street     | housenumber and streetname |
+| city       | city |
+| county     | county |
+| state      | state |
+| country    | country |
+| postalcode | postal code |
+
+The structured form of the search query allows to lookup up an address
+that is already split into its components. Each parameter represents a field
+of the address. All parameters are optional. You should only use the ones
+that are relevant for the address you want to geocode.
+
+!!! Attention
+    Cannot be combined with the `q=<query>` parameter. Newer versions of
+    the API will return an error if you do so. Older versions simply return
+    unexpected results.
+
+## Parameters
+
+The following parameters can be used to further restrict the search and
+change the output. They are usable for both forms of the search query.
 
 ### Output format
 
-* `format=[xml|json|jsonv2|geojson|geocodejson]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| format    | one of: `xml`, `json`, `jsonv2`, `geojson`, `geocodejson` | `jsonv2` |
 
-See [Place Output Formats](Output.md) for details on each format. (Default: jsonv2)
+See [Place Output Formats](Output.md) for details on each format.
 
 !!! note
     The Nominatim service at
@@ -57,52 +84,150 @@ See [Place Output Formats](Output.md) for details on each format. (Default: json
     has a different default behaviour for historical reasons. When the
     `format` parameter is omitted, the request will be forwarded to the Web UI.
 
-* `json_callback=<string>`
 
-Wrap JSON output in a callback function ([JSONP](https://en.wikipedia.org/wiki/JSONP)) i.e. `<string>(<json>)`.
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| json_callback | function name | _unset_ |
+
+When given, then JSON output will be wrapped in a callback function with
+the given name. See [JSONP](https://en.wikipedia.org/wiki/JSONP) for more
+information.
+
 Only has an effect for JSON output formats.
 
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| limit     | number | 10 |
+
+Limit the maximum number of returned results. Cannot be more than 40.
+Nominatim may decide to return less results than given, if additional
+results do not sufficiently match the query.
+
+
 ### Output details
 
-* `addressdetails=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| addressdetails | 0 or 1 | 0 |
 
-Include a breakdown of the address into elements. (Default: 0)
+When set to 1, include a breakdown of the address into elements.
+The exact content of the address breakdown depends on the output format.
+
+!!! tip
+    If you are interested in a stable classification of address categories
+    (suburb, city, state, etc), have a look at the `geocodejson` format.
+    All other formats return classifications according to OSM tagging.
+    There is a much larger set of categories and they are not always consistent,
+    which makes them very hard to work with.
 
 
-* `extratags=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| extratags | 0 or 1 | 0 |
 
-Include additional information in the result if available,
-e.g. wikipedia link, opening hours. (Default: 0)
+When set to 1, the response include any additional information in the result
+that is available in the database, e.g. wikipedia link, opening hours.
 
 
-* `namedetails=[0|1]`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| namedetails | 0 or 1 | 0 |
 
-Include a list of alternative names in the results. These may include
-language variants, references, operator and brand. (Default: 0)
+When set to 1, include a full list of names for the result. These may include
+language variants, older names, references and brand.
 
 
 ### Language of results
 
-* `accept-language=<browser language string>`
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| accept-language | browser language string | content of "Accept-Language" HTTP header |
 
-Preferred language order for showing search results, overrides the value
-specified in the ["Accept-Language" HTTP header](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Language).
-Either use a standard RFC2616 accept-language string or a simple
-comma-separated list of language codes.
+Preferred language order for showing search results. This may either be
+a simple comma-separated list of language codes or have the same format
+as the ["Accept-Language" HTTP header](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Language).
 
-### Result limitation
+!!! tip
+    First-time users of Nominatim tend to be confused that they get different
+    results when using Nominatim in the browser versus in a command-line tool
+    like wget or curl. The command-line tools
+    usually don't send any Accept-Language header, prompting Nominatim
+    to show results in the local language. Browsers on the contratry always
+    send the currently chosen browser language.
 
-* `countrycodes=<countrycode>[,<countrycode>][,<countrycode>]...`
+### Result restriction
 
-Limit search results to one or more countries. `<countrycode>` must be the
-[ISO 3166-1alpha2](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2) code,
-e.g. `gb` for the United Kingdom, `de` for Germany.
+There are two ways to influence the results. *Filters* exclude certain
+kinds of results completely. *Boost parameters* only change the order of the
+results and thus give a preference to some results over others.
+
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| countrycodes | comma-separated list of country codes | _unset_ |
+
+Filter that limits the search results to one or more countries.
+The country code must be the
+[ISO 3166-1alpha2](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2) code
+of the country, e.g. `gb` for the United Kingdom, `de` for Germany.
 
 Each place in Nominatim is assigned to one country code based
 on OSM country boundaries. In rare cases a place may not be in any country
-at all, for example, in international waters.
+at all, for example, when it is in international waters. These places are
+also excluded when the filter is set.
 
-* `exclude_place_ids=<place_id,[place_id],[place_id]`
+!!! Note
+    This parameter should not be confused with the 'country' parameter of
+    the structured query. The 'country' parameter contains a search term
+    and will be handled with some fuzziness. The `countrycodes` parameter
+    is a hard filter and as such should be preferred. Having both parameters
+    in the same query will work. If the parameters contradict each other,
+    the search will come up empty.
+
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| layer     | comma-separated list of: `address`, `poi`, `railway`, `natural`, `manmade` | _unset_ (no restriction) |
+
+**`[Python-only]`**
+
+The layer filter allows to select places by themes.
+
+The `address` layer contains all places that make up an address:
+address points with house numbers, streets, inhabited places (suburbs, villages,
+cities, states tec.) and administrative boundaries.
+
+The `poi` layer selects all point of interest. This includes classic POIs like
+restaurants, shops, hotels but also less obvious features like recycling bins,
+guideposts or benches.
+
+The `railway` layer includes railway infrastructure like tracks.
+Note that in Nominatim's standard configuration, only very few railway
+features are imported into the database.
+
+The `natural` layer collects features like rivers, lakes and mountains while
+the `manmade` layer functions as a catch-all for features not covered by the
+other layers.
+
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| featureType | one of: `country`, `state`, `city`, `settlement` | _unset_ |
+
+The featureType allows to have a more fine-grained selection for places
+from the address layer. Results can be restricted to places that make up
+the 'state', 'country' or 'city' part of an address. A featureType of
+settlement selects any human inhabited feature from 'state' down to
+'neighbourhood'.
+
+When featureType is set, then results are automatically restricted
+to the address layer (see above).
+
+!!! tip
+    Instead of using the featureType filters `country`, `state` or `city`,
+    you can also use a structured query without the finer-grained parameters
+    amenity or street.
+
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| exclude_place_ids | comma-separated list of place ids |
 
 If you do not want certain OSM objects to appear in the search
 result, give a comma separated list of the `place_id`s you want to skip.
@@ -110,180 +235,212 @@ This can be used to retrieve additional search results. For example, if a
 previous query only returned a few results, then including those here would
 cause the search to return other, less accurate, matches (if possible).
 
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| viewbox   | `<x1>,<y1>,<x2>,<y2>` | _unset_ |
 
-* `limit=<integer>`
+Boost parameter which focuses the search on the given area.
+Any two corner points of the box are accepted as long as they make a proper
+box. `x` is longitude, `y` is latitude.
 
-Limit the number of returned results. (Default: 10, Maximum: 50)
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| bounded   | 0 or 1 | 0       |
 
+When set to 1, then it turns the 'viewbox' parameter (see above) into
+a filter parameter, excluding any results outside the viewbox.
 
-* `viewbox=<x1>,<y1>,<x2>,<y2>`
-
-The preferred area to find search results. Any two corner points of the box
-are accepted as long as they span a real box. `x` is longitude,
-`y` is latitude.
-
-
-* `bounded=[0|1]`
-
-When a viewbox is given, restrict the result to items contained within that
-viewbox (see above). When `viewbox` and `bounded=1` are given, an amenity
-only search is allowed. Give the special keyword for the amenity in square
+When `bounded=1` is given and the viewbox is small enough, then an amenity-only
+search is allowed. Give the special keyword for the amenity in square
 brackets, e.g. `[pub]` and a selection of objects of this type is returned.
-There is no guarantee that the result is complete. (Default: 0)
+There is no guarantee that the result returns all objects in the area.
 
 
 ### Polygon output
 
-* `polygon_geojson=1`
-* `polygon_kml=1`
-* `polygon_svg=1`
-* `polygon_text=1`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| polygon_geojson | 0 or 1 | 0 |
+| polygon_kml     | 0 or 1 | 0 |
+| polygon_svg     | 0 or 1 | 0 |
+| polygon_text    | 0 or 1 | 0 |
 
-Output geometry of results as a GeoJSON, KML, SVG or WKT. Only one of these
-options can be used at a time. (Default: 0)
+Add the full geometry of the place to the result output. Output formats
+in GeoJSON, KML, SVG or WKT are supported. Only one of these
+options can be used at a time.
 
-* `polygon_threshold=0.0`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| polygon_threshold | floating-point number | 0.0 |
 
-Return a simplified version of the output geometry. The parameter is the
+When one of the polygon_* outputs is chosen, return a simplified version
+of the output geometry. The parameter describes the
 tolerance in degrees with which the geometry may differ from the original
-geometry. Topology is preserved in the result. (Default: 0.0)
+geometry. Topology is preserved in the geometry.
 
 ### Other
 
-* `email=<valid email address>`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| email     | valid email address | _unset_ |
 
 If you are making large numbers of request please include an appropriate email
-address to identify your requests. See Nominatim's [Usage Policy](https://operations.osmfoundation.org/policies/nominatim/) for more details.
+address to identify your requests. See Nominatim's
+[Usage Policy](https://operations.osmfoundation.org/policies/nominatim/) for more details.
 
-* `dedupe=[0|1]`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| dedupe    | 0 or 1 | 1       |
 
 Sometimes you have several objects in OSM identifying the same place or
 object in reality. The simplest case is a street being split into many
 different OSM ways due to different characteristics. Nominatim will
-attempt to detect such duplicates and only return one match unless
-this parameter is set to 0. (Default: 1)
+attempt to detect such duplicates and only return one match. Setting
+this parameter to 0 disables this deduplication mechanism and
+ensures that all results are returned.
 
-* `debug=[0|1]`
+| Parameter | Value  | Default |
+|-----------| -----  | ------- |
+| debug     | 0 or 1 | 0       |
 
 Output assorted developer debug information. Data on internals of Nominatim's
-"Search Loop" logic, and SQL queries. The output is (rough) HTML format.
-This overrides the specified machine readable format. (Default: 0)
-
+"search loop" logic, and SQL queries. The output is HTML format.
+This overrides the specified machine readable format.
 
 
 ## Examples
 
 
-##### XML with kml polygon
+##### XML with KML polygon
 
-* [https://nominatim.openstreetmap.org/search?q=135+pilkington+avenue,+birmingham&format=xml&polygon_geojson=1&addressdetails=1](https://nominatim.openstreetmap.org/search?q=135+pilkington+avenue,+birmingham&format=xml&polygon_geojson=1&addressdetails=1)
+* [https://nominatim.openstreetmap.org/search?q=135+pilkington+avenue,+birmingham&format=xml&polygon_kml=1&addressdetails=1](https://nominatim.openstreetmap.org/search?q=135+pilkington+avenue,+birmingham&format=xml&polygon_kml=1&addressdetails=1)
 
 ```xml
-  <searchresults timestamp="Sat, 07 Nov 09 14:42:10 +0000" querystring="135 pilkington, avenue birmingham" polygon="true">
-    <place
-      place_id="1620612" osm_type="node" osm_id="452010817"
-      boundingbox="52.548641204834,52.5488433837891,-1.81612110137939,-1.81592094898224"
-      lat="52.5487429714954" lon="-1.81602098644987"
-      display_name="135, Pilkington Avenue, Wylde Green, City of Birmingham, West Midlands (county), B72, United Kingdom"
-      class="place" type="house">
-      <geokml>
-        <Polygon>
-          <outerBoundaryIs>
-            <LinearRing>
-              <coordinates>-1.816513,52.548756599999997 -1.816434,52.548747300000002 -1.816429,52.5487629 -1.8163717,52.548756099999999 -1.8163464,52.548834599999999 -1.8164599,52.548848100000001 -1.8164685,52.5488213 -1.8164913,52.548824000000003 -1.816513,52.548756599999997</coordinates>
-            </LinearRing>
-          </outerBoundaryIs>
-        </Polygon>
-      </geokml>
-      <house_number>135</house_number>
-      <road>Pilkington Avenue</road>
-      <village>Wylde Green</village>
-      <town>Sutton Coldfield</town>
-      <city>City of Birmingham</city>
-      <county>West Midlands (county)</county>
-      <postcode>B72</postcode>
-      <country>United Kingdom</country>
-      <country_code>gb</country_code>
-    </place>
-  </searchresults>
+<?xml version="1.0" encoding="UTF-8" ?>
+<searchresults timestamp="Tue, 08 Aug 2023 15:45:41 +00:00"
+               attribution="Data © OpenStreetMap contributors, ODbL 1.0. http://osm.org/copyright"
+               querystring="135 pilkington avenue, birmingham"
+               more_url="https://nominatim.openstreetmap.org/search?q=135+pilkington+avenue%2C+birmingham&amp;polygon_kml=1&amp;addressdetails=1&amp;limit=20&amp;exclude_place_ids=125279639&amp;format=xml"
+               exclude_place_ids="125279639">
+  <place place_id="125279639"
+         osm_type="way"
+         osm_id="90394480"
+         lat="52.5487921"
+         lon="-1.8164308"
+         boundingbox="52.5487473,52.5488481,-1.8165130,-1.8163464"
+         place_rank="30"
+         address_rank="30"
+         display_name="135, Pilkington Avenue, Maney, Sutton Coldfield, Wylde Green, Birmingham, West Midlands Combined Authority, England, B72 1LH, United Kingdom"
+         class="building"
+         type="residential"
+         importance="9.999999994736442e-08">
+    <geokml>
+      <Polygon>
+        <outerBoundaryIs>
+          <LinearRing>
+            <coordinates>-1.816513,52.5487566 -1.816434,52.5487473 -1.816429,52.5487629 -1.8163717,52.5487561 -1.8163464,52.5488346 -1.8164599,52.5488481 -1.8164685,52.5488213 -1.8164913,52.548824 -1.816513,52.5487566</coordinates>
+          </LinearRing>
+        </outerBoundaryIs>
+      </Polygon>
+    </geokml>
+    <house_number>135</house_number>
+    <road>Pilkington Avenue</road>
+    <hamlet>Maney</hamlet>
+    <town>Sutton Coldfield</town>
+    <village>Wylde Green</village>
+    <city>Birmingham</city>
+    <ISO3166-2-lvl8>GB-BIR</ISO3166-2-lvl8>
+    <state_district>West Midlands Combined Authority</state_district>
+    <state>England</state>
+    <ISO3166-2-lvl4>GB-ENG</ISO3166-2-lvl4>
+    <postcode>B72 1LH</postcode>
+    <country>United Kingdom</country>
+    <country_code>gb</country_code>
+  </place>
+</searchresults>
 ```
 
 ##### JSON with SVG polygon
 
-[https://nominatim.openstreetmap.org/search/Unter%20den%20Linden%201%20Berlin?format=json&addressdetails=1&limit=1&polygon_svg=1](https://nominatim.openstreetmap.org/search/Unter%20den%20Linden%201%20Berlin?format=json&addressdetails=1&limit=1&polygon_svg=1)
+[https://nominatim.openstreetmap.org/search?q=Unter%20den%20Linden%201%20Berlin&format=json&addressdetails=1&limit=1&polygon_svg=1](https://nominatim.openstreetmap.org/search?q=Unter%20den%20Linden%201%20Berlin&format=json&addressdetails=1&limit=1&polygon_svg=1)
 
 ```json
-    {
-        "address": {
-            "city": "Berlin",
-            "city_district": "Mitte",
-            "construction": "Unter den Linden",
-            "continent": "European Union",
-            "country": "Deutschland",
-            "country_code": "de",
-            "house_number": "1",
-            "neighbourhood": "Scheunenviertel",
-            "postcode": "10117",
-            "public_building": "Kommandantenhaus",
-            "state": "Berlin",
-            "suburb": "Mitte"
-        },
-        "boundingbox": [
-            "52.5170783996582",
-            "52.5173187255859",
-            "13.3975105285645",
-            "13.3981599807739"
-        ],
-        "class": "amenity",
-        "display_name": "Kommandantenhaus, 1, Unter den Linden, Scheunenviertel, Mitte, Berlin, 10117, Deutschland, European Union",
-        "importance": 0.73606775332943,
-        "lat": "52.51719785",
-        "licence": "Data \u00a9 OpenStreetMap contributors, ODbL 1.0. https://www.openstreetmap.org/copyright",
-        "lon": "13.3978352028938",
-        "osm_id": "15976890",
-        "osm_type": "way",
-        "place_id": "30848715",
-        "svg": "M 13.397511 -52.517283599999999 L 13.397829400000001 -52.517299800000004 13.398131599999999 -52.517315099999998 13.398159400000001 -52.517112099999999 13.3975388 -52.517080700000001 Z",
-        "type": "public_building"
-    }
+[
+  {
+    "address": {
+      "ISO3166-2-lvl4": "DE-BE",
+      "borough": "Mitte",
+      "city": "Berlin",
+      "country": "Deutschland",
+      "country_code": "de",
+      "historic": "Kommandantenhaus",
+      "house_number": "1",
+      "neighbourhood": "Friedrichswerder",
+      "postcode": "10117",
+      "road": "Unter den Linden",
+      "suburb": "Mitte"
+    },
+    "boundingbox": [
+      "52.5170798",
+      "52.5173311",
+      "13.3975116",
+      "13.3981577"
+    ],
+    "class": "historic",
+    "display_name": "Kommandantenhaus, 1, Unter den Linden, Friedrichswerder, Mitte, Berlin, 10117, Deutschland",
+    "importance": 0.8135042058306902,
+    "lat": "52.51720765",
+    "licence": "Data © OpenStreetMap contributors, ODbL 1.0. https://osm.org/copyright",
+    "lon": "13.397834399325466",
+    "osm_id": 15976890,
+    "osm_type": "way",
+    "place_id": 108681845,
+    "svg": "M 13.3975116 -52.5172905 L 13.397549 -52.5170798 13.397715 -52.5170906 13.3977122 -52.5171064 13.3977392 -52.5171086 13.3977417 -52.5170924 13.3979655 -52.5171069 13.3979623 -52.5171233 13.3979893 -52.5171248 13.3979922 -52.5171093 13.3981577 -52.5171203 13.398121 -52.5173311 13.3978115 -52.5173103 Z",
+    "type": "house"
+  }
+]
 ```
 
 ##### JSON with address details
 
-[https://nominatim.openstreetmap.org/?addressdetails=1&q=bakery+in+berlin+wedding&format=json&limit=1](https://nominatim.openstreetmap.org/?addressdetails=1&q=bakery+in+berlin+wedding&format=json&limit=1)
+[https://nominatim.openstreetmap.org/search?addressdetails=1&q=bakery+in+berlin+wedding&format=jsonv2&limit=1](https://nominatim.openstreetmap.org/search?addressdetails=1&q=bakery+in+berlin+wedding&format=jsonv2&limit=1)
 
 ```json
-    {
-        "address": {
-            "bakery": "B\u00e4cker Kamps",
-            "city_district": "Mitte",
-            "continent": "European Union",
-            "country": "Deutschland",
-            "country_code": "de",
-            "footway": "Bahnsteig U6",
-            "neighbourhood": "Sprengelkiez",
-            "postcode": "13353",
-            "state": "Berlin",
-            "suburb": "Wedding"
-        },
-        "boundingbox": [
-            "52.5460929870605",
-            "52.5460968017578",
-            "13.3591794967651",
-            "13.3591804504395"
-        ],
-        "class": "shop",
-        "display_name": "B\u00e4cker Kamps, Bahnsteig U6, Sprengelkiez, Wedding, Mitte, Berlin, 13353, Deutschland, European Union",
-        "icon": "https://nominatim.openstreetmap.org/images/mapicons/shopping_bakery.p.20.png",
-        "importance": 0.201,
-        "lat": "52.5460941",
-        "licence": "Data \u00a9 OpenStreetMap contributors, ODbL 1.0. https://www.openstreetmap.org/copyright",
-        "lon": "13.35918",
-        "osm_id": "317179427",
-        "osm_type": "node",
-        "place_id": "1453068",
-        "type": "bakery"
-    }
+[
+  {
+    "address": {
+      "ISO3166-2-lvl4": "DE-BE",
+      "borough": "Mitte",
+      "city": "Berlin",
+      "country": "Deutschland",
+      "country_code": "de",
+      "neighbourhood": "Sprengelkiez",
+      "postcode": "13347",
+      "road": "Lindower Straße",
+      "shop": "Ditsch",
+      "suburb": "Wedding"
+    },
+    "addresstype": "shop",
+    "boundingbox": [
+      "52.5427201",
+      "52.5427654",
+      "13.3668619",
+      "13.3669442"
+    ],
+    "category": "shop",
+    "display_name": "Ditsch, Lindower Straße, Sprengelkiez, Wedding, Mitte, Berlin, 13347, Deutschland",
+    "importance": 9.99999999995449e-06,
+    "lat": "52.54274275",
+    "licence": "Data © OpenStreetMap contributors, ODbL 1.0. http://osm.org/copyright",
+    "lon": "13.36690305710228",
+    "name": "Ditsch",
+    "osm_id": 437595031,
+    "osm_type": "way",
+    "place_id": 204751033,
+    "place_rank": 30,
+    "type": "bakery"
+  }
+]
 ```
 
 ##### GeoJSON

docs/api/Status.md

@@ -1,35 +1,50 @@
 # Status
 
-Useful for checking if the service and database is running. The JSON output also shows
+Report on the state of the service and database. Useful for checking if the
+service is up and running. The JSON output also reports
 when the database was last updated.
 
+## Endpoint
+
+The status API has the following format:
+
+```
+https://nominatim.openstreetmap.org/status
+```
+
+!!! danger "Deprecation warning"
+    The API can also be used with the URL
+    `https://nominatim.openstreetmap.org/status.php`. This is now deprecated
+    and will be removed in future versions.
+
+
 ## Parameters
 
-* `format=[text|json]` (defaults to 'text')
+The status endpoint takes a single optional parameter:
+
+| Parameter | Value | Default |
+|-----------| ----- | ------- |
+| format    | one of: `text`, `json` | 'text' |
+
+Selects the output format. See below.
 
 
 ## Output
 
 #### Text format
 
-```
-   https://nominatim.openstreetmap.org/status.php
-```
+When everything is okay, a status code 200 is returned and a simple message: `OK`
 
-will return HTTP status code 200 and print `OK`.
-
-On error it will return HTTP status code 500 and print a message, e.g.
+On error it will return HTTP status code 500 and print a detailed error message, e.g.
 `ERROR: Database connection failed`.
 
 
 
 #### JSON format
 
-```
-   https://nominatim.openstreetmap.org/status.php?format=json
-```
+Always returns a HTTP code 200, when the status call could be executed.
 
-will return HTTP code 200 and a structure
+On success a JSON dictionary with the following structure is returned:
 
 ```json
   {
@@ -45,8 +60,8 @@ The `software_version` field contains the version of Nominatim used to serve
 the API. The `database_version` field contains the version of the data format
 in the database.
 
-On error will also return HTTP status code 200 and a structure with error
-code and message, e.g.
+On error will return a shorter JSON dictionary with the error message
+and status only, e.g.
 
 ```json
    {
@@ -54,14 +69,3 @@ code and message, e.g.
        "message": "Database connection failed"
    }
 ```
-
-Possible status codes are
-
-|     | message                        | notes                                                             |
-| --- | ------------------------------ | ----------------------------------------------------------------- |
-| 700 | "No database"                  | connection failed                                                 |
-| 701 | "Module failed"                | database could not load nominatim.so                              |
-| 702 | "Module call failed"           | nominatim.so loaded but calling a function failed                 |
-| 703 | "Query failed"                 | test query against a database table failed                        |
-| 704 | "No value"                     | test query worked but returned no results                         |
-| 705 | "Import date is not available" | No import dates were returned (enabling replication can fix this) |

docs/customize/Import-Styles.md

@@ -1,149 +1,439 @@
 ## Configuring the Import
 
-Which OSM objects are added to the database and which of the tags are used
-can be configured via the import style configuration file. This
-is a JSON file which contains a list of rules which are matched against every
-tag of every object and then assign the tag its specific role.
+In the very first step of a Nominatim import, OSM data is loaded into the
+database. Nominatim uses [osm2pgsql](https://osm2pgsql.org) for this task.
+It comes with a [flex style](https://osm2pgsql.org/doc/manual.html#the-flex-output)
+specifically tailored to filter and convert OSM data into Nominatim's
+internal data representation.
 
-The style to use is given by the `NOMINATIM_IMPORT_STYLE` configuration
-option. There are a number of default styles, which are explained in detail
-in the [Import section](../admin/Import.md#filtering-imported-data). These
-standard styles may be referenced by their name.
+There are a number of default configurations for the flex style which
+result in geocoding databases of different detail. The
+[Import section](../admin/Import.md#filtering-imported-data) explains
+these default configurations in detail.
 
 You can also create your own custom style. Put the style file into your
 project directory and then set `NOMINATIM_IMPORT_STYLE` to the name of the file.
 It is always recommended to start with one of the standard styles and customize
-those. You find the standard styles under the name `import-<stylename>.style`
+those. You find the standard styles under the name `import-<stylename>.lua`
 in the standard Nominatim configuration path (usually `/etc/nominatim` or
 `/usr/local/etc/nominatim`).
 
-The remainder of the page describes the format of the file.
+The remainder of the page describes how the flex style works and how to
+customize it.
 
-### Configuration Rules
+### The `flex-base.lua` module
 
-A single rule looks like this:
+The core of Nominatim's flex import configuration is the `flex-base` module.
+It defines the table layout used by Nominatim and provides standard
+implementations for the import callbacks that make it easy to customize
+how OSM tags are used by Nominatim.
+
+Every custom style should include this module to make sure that the correct
+tables are created. Thus start your custom style as follows:
+
+``` lua
+local flex = require('flex-base')
 
-```json
-{
-    "keys" : ["key1", "key2", ...],
-    "values" : {
-        "value1" : "prop",
-        "value2" : "prop1,prop2"
-    }
-}
 ```
 
-A rule first defines a list of keys to apply the rule to. This is always a list
-of strings. The string may have four forms. An empty string matches against
-any key. A string that ends in an asterisk `*` is a prefix match and accordingly
-matches against any key that starts with the given string (minus the `*`). A
-suffix match can be defined similarly with a string that starts with a `*`. Any
-other string constitutes an exact match.
+The following sections explain how the module can be customized.
 
-The second part of the rules defines a list of values and the properties that
-apply to a successful match. Value strings may be either empty, which
-means that they match any value, or describe an exact match. Prefix
-or suffix matching of values is not possible.
 
-For a rule to match, it has to find a valid combination of keys and values. The
-resulting property is that of the matched values.
+### Changing the recognized tags
 
-The rules in a configuration file are processed sequentially and the first
-match for each tag wins.
+If you just want to change which OSM tags are recognized during import,
+then there are a number of convenience functions to set the tag lists used
+during the processing.
 
-A rule where key and value are the empty string is special. This defines the
-fallback when none of the rules match. The fallback is always used as a last
-resort when nothing else matches, no matter where the rule appears in the file.
-Defining multiple fallback rules is not allowed. What happens in this case,
-is undefined.
+!!! warning
+    There are no built-in defaults for the tag lists, so all the functions
+    need to be called from your style script to fully process the data.
+    Make sure you start from one of the default style and only modify
+    the data you are interested in. You can also derive your style from an
+    existing style by importing the appropriate module, e.g.
+    `local flex = require('import-street')`.
 
-### Tag Properties
+Many of the following functions take _key match lists_. These lists can
+contain three kinds of strings to match against tag keys:
+A string that ends in an asterisk `*` is a prefix match and accordingly matches
+against any key that starts with the given string (minus the `*`). 
+A suffix match can be defined similarly with a string that starts with a `*`.
+Any other string is matched exactly against tag keys.
 
-One or more of the following properties may be given for each tag:
 
-* `main`
+#### `set_main_tags()` - principal tags
 
-    A principal tag. A new row will be added for the object with key and value
-    as `class` and `type`.
+If a principal or main tag is found on an OSM object, then the object
+is included in Nominatim's search index. A single object may also have
+multiple main tags. In that case, the object will be included multiple
+times in the index, once for each main tag.
 
-* `with_name`
+The flex script distinguishes between four types of main tags:
 
-    When the tag is a principal tag (`main` property set): only really add a new
-    row, if there is any name tag found (a reference tag is not sufficient, see
-    below).
+* __always__: a main tag that is used unconditionally
+* __named__: consider this main tag only, if the object has a proper name
+  (a reference is not enough, see below).
+* __named_with_key__: consider this main tag only, when the object has
+  a proper name with a domain prefix. For example, if the main tag is
+  `bridge=yes`, then it will only be added as an extra row, if there is
+  a tag `bridge:name[:XXX]` for the same object. If this property is set,
+  all other names that are not domain-specific are ignored.
+* __fallback__: use this main tag only, if there is no other main tag.
+  Fallback always implied `named`, i.e. fallbacks are only tried for
+  named objects.
 
-* `with_name_key`
+The `set_main_tags()` function takes exactly one table parameter which
+defines the keys and key/value combinations to include and the kind of
+main tag. Each lua table key defines an OSM tag key. The value may
+be a string defining the kind of main key as described above. Then the tag will
+be considered a main tag for any possible value. To further restrict
+which values are acceptable, give a table with the permitted values
+and their kind of main tag. If the table contains a simple value without
+key, then this is used as default for values that are not listed.
 
-    When the tag is a principal tag (`main` property set): only really add a new
-    row, if there is also a name tag that matches the key of the principal tag.
-    For example, if the main tag is `bridge=yes`, then it will only be added as
-    an extra row, if there is a tag `bridge:name[:XXX]` for the same object.
-    If this property is set, all other names that are not domain-specific are
-    ignored.
+!!! example
+    ``` lua
+    local flex = require('import-full')
 
-* `fallback`
+    flex.set_main_tags{
+        boundary = {administrative = 'named'},
+        highway = {'always', street_lamp = 'named'},
+        landuse = 'fallback'
+    }
+    ```
 
-    When the tag is a principal tag (`main` property set): only really add a new
-    row, when no other principal tags for this object have been found. Only one
-    fallback tag can win for an object.
+    In this example an object with a `boundary` tag will only be included
+    when it has a value of `administrative`. Objects with `highway` tags are
+    always included. However when the value is `street_lamp` then the object
+    must have a name, too. With any other value, the object is included
+    independently of the name. Finally, if a `landuse` tag is present then
+    it will be used independely of the concrete value if neither boundary
+    nor highway tags were found and the object is named.
 
-* `operator`
 
-    When the tag is a principal tag (`main` property set): also include the
-    `operator` tag in the list of names. This is a special construct for an
-    out-dated tagging practise in OSM. Fuel stations and chain restaurants
-    in particular used to have the name of the chain tagged as `operator`.
-    These days the chain can be more commonly found in the `brand` tag but
-    there is still enough old data around to warrant this special case.
+#### `set_prefilters()` - ignoring tags
 
-* `name`
+Pre-filtering of tags allows to ignore them for any further processing.
+Thus pre-filtering takes precedence over any other tag processing. This is
+useful when some specific key/value combinations need to be excluded from
+processing. When tags are filtered, they may either be deleted completely
+or moved to `extratags`. Extra tags are saved with the object and returned
+to the user when requested, but are not used otherwise.
 
-    Add tag to the list of names.
+`set_prefilters()` takes a table with four optional fields:
 
-* `ref`
+* __delete_keys__ is a _key match list_ for tags that should be deleted
+* __delete_tags__ contains a table of tag keys pointing to a list of tag
+  values. Tags with matching key/value pairs are deleted.
+* __extra_keys__ is a _key match list_ for tags which should be saved into
+  extratags
+* __extra_tags__ contains a table of tag keys pointing to a list of tag
+  values. Tags with matching key/value pairs are moved to extratags.
 
-    Add tag to the list of names as a reference. At the moment this only means
-    that the object is not considered to be named for `with_name`.
+Key list may contain three kinds of strings:
+A string that ends in an asterisk `*` is a prefix match and accordingly matches
+against any key that starts with the given string (minus the `*`). 
+A suffix match can be defined similarly with a string that starts with a `*`.
+Any other string is matched exactly against tag keys.
 
-* `address`
+!!! example
+    ``` lua
+    local flex = require('import-full')
 
-    Add tag to the list of address tags. If the tag starts with `addr:` or
-    `is_in:`, then this prefix is cut off before adding it to the list.
+    flex.set_prefilters{
+        delete_keys = {'source', 'source:*'},
+        extra_tags = {amenity = {'yes', 'no'}}
+    }
+    flex.set_main_tags{
+        amenity = 'always'
+    }
+    ```
 
-* `postcode`
+    In this example any tags `source` and tags that begin with `source:`  are
+    deleted before any other processing is done. Getting rid of frequent tags
+    this way can speed up the import.
 
-    Add the value as a postcode to the address tags. If multiple tags are
-    candidate for postcodes, one wins out and the others are dropped.
+    Tags with `amenity=yes` or `amenity=no` are moved to extratags. Later
+    all tags with an `amenity` key are made a main tag. This effectively means
+    that Nominatim will use all amenity tags except for those with value
+    yes and no.
 
-* `country`
+#### `set_name_tags()` - defining names
 
-    Add the value as a country code to the address tags. The value must be a
-    two letter country code, otherwise it is ignored. If there are multiple
-    tags that match, then one wins out and the others are dropped.
+The flex script distinguishes between two kinds of names:
 
-* `house`
+* __main__: the primary names make an object fully searchable.
+  Main tags of type _named_ will only cause the object to be included when
+  such a primary name is present. Primary names are usually those found
+  in the `name` tag and its variants.
+* __extra__: extra names are still added to the search index but they are
+  alone not sufficient to make an object named.
 
-    If no principle tags can be found for the object, still add the object with
-    `class`=`place` and `type`=`house`. Use this for address nodes that have no
-    other function.
+`set_name_tags()` takes a table with two optional fields `main` and `extra`.
+They take _key match lists_ for main and extra names respectively.
 
-* `interpolation`
+!!! example
+    ``` lua
+    local flex = require('flex-base')
 
-    Add this object as an address interpolation (appears as `class`=`place` and
-    `type`=`houses` in the database).
+    flex.set_main_tags{highway = {traffic_light = 'named'}}
+    flex.set_name_tags{main = {'name', 'name:*'},
+                       extra = {'ref'}
+                      }
+    ```
 
-* `extra`
+    This example creates a search index over traffic lights but will
+    only include those that have a common name and not those which just
+    have some reference ID from the city.
 
-    Add tag to the list of extra tags.
+#### `set_address_tags()` - defining address parts
 
-* `skip`
+Address tags will be used to build up the address of an object.
 
-    Skip the tag completely. Useful when a custom default fallback is defined
-    or to define exceptions to rules.
+`set_address_tags()` takes a table with arbitrary fields pointing to
+_key match lists_. To fields have a special meaning:
 
-A rule can define as many of these properties for one match as it likes. For
-example, if the property is `"main,extra"` then the tag will open a new row
-but also have the tag appear in the list of extra tags.
+* __main__: defines
+the tags that make a full address object out of the OSM object. This
+is usually the housenumber or variants thereof. If a main address tag
+appears, then the object will always be included, if necessary with a
+fallback of `place=house`. If the key has a prefix of `addr:` or `is_in:`
+this will be stripped.
+
+* __extra__: defines all supplementary tags for addresses, tags like `addr:street`, `addr:city` etc. If the key has a prefix of `addr:` or `is_in:` this will be stripped.
+
+All other fields will be handled as summary fields. If a key matches the
+key match list, then its value will be added to the address tags with the
+name of the field as key. If multiple tags match, then an arbitrary one
+wins.
+
+Country tags are handled slightly special. Only tags with a two-letter code
+are accepted, all other values are discarded.
+
+!!! example
+    ``` lua
+    local flex = require('import-full')
+
+    flex.set_address_tags{
+        main = {'addr:housenumber'},
+        extra = {'addr:*'},
+        postcode = {'postal_code', 'postcode', 'addr:postcode'},
+        country = {'country-code', 'ISO3166-1'}
+    }
+    ```
+
+    In this example all tags which begin with `addr:` will be saved in
+    the address tag list. If one of the tags is `addr:housenumber`, the
+    object will fall back to be entered as a `place=house` in the database
+    unless there is another interested main tag to be found.
+
+    Tags with keys `country-code` and `ISO3166-1` are saved with their
+    value under `country` in the address tag list. The same thing happens
+    to postcodes, they will always be saved under the key `postcode` thus
+    normalizing the multitude of keys that are used in the OSM database.
+
+
+#### `set_unused_handling()` - processing remaining tags
+
+This function defines what to do with tags that remain after all tags
+have been classified using the functions above. There are two ways in
+which the function can be used:
+
+`set_unused_handling(delete_keys = ..., delete_tags = ...)` deletes all
+keys that match the descriptions in the parameters and moves all remaining
+tags into the extratags list.
+`set_unused_handling(extra_keys = ..., extra_tags = ...)` moves all tags
+matching the parameters into the extratags list and then deletes the remaining
+tags. For the format of the parameters see the description in `set_prefilters()`
+above.
+
+!!! example
+    ``` lua
+    local flex = require('import-full')
+
+    flex.set_address_tags{
+        main = {'addr:housenumber'},
+        extra = {'addr:*', 'tiger:county'}
+    }
+    flex.set_unused_handling{delete_keys = {'tiger:*'}}
+    ```
+
+    In this example all remaining tags except those beginning with `tiger:`
+    are moved to the extratags list. Note that it is not possible to
+    already delete the tiger tags with `set_prefilters()` because that
+    would remove tiger:county before the address tags are processed.
+
+### Customizing osm2pgsql callbacks
+
+osm2pgsql expects the flex style to implement three callbacks, one process
+function per OSM type. If you want to implement special handling for
+certain OSM types, you can override the default implementations provided
+by the flex-base module.
+
+#### Changing the relation types to be handled
+
+The default scripts only allows relations of type `multipolygon`, `boundary`
+and `waterway`. To add other types relations, set `RELATION_TYPES` for
+the type to the kind of geometry that should be created. The following
+kinds of geometries can be used:
+
+* __relation_as_multipolygon__ creates a (Multi)Polygon from the ways in
+  the relation. If the ways do not form a valid area, then the object is
+  silently discarded.
+* __relation_as_multiline__ creates a (Multi)LineString from the ways in
+  the relations. Ways are combined as much as possible without any regards
+  to their order in the relation.
+
+!!! Example
+    ``` lua
+    local flex = require('import-full')
+
+    flex.RELATION_TYPES['site'] = flex.relation_as_multipolygon
+    ```
+
+    With this line relations of `type=site` will be included in the index
+    according to main tags found. This only works when the site relation
+    resolves to a valid area. Nodes in the site relation are not part of the
+    geometry.
+
+
+#### Adding additional logic to processing functions
+
+The default processing functions are also exported by the flex-base module
+as `process_node`, `process_way` and `process_relation`. These can be used
+to implement your own processing functions with some additional processing
+logic.
+
+!!! Example
+    ``` lua
+    local flex = require('import-full')
+
+    function osm2pgsql.process_relation(object)
+        if object.tags.boundary ~= 'administrative' or object.tags.admin_level ~= '2' then
+          flex.process_relation(object)
+        end
+    end
+    ```
+
+    This example discards all country-level boundaries and uses standard
+    handling for everything else. This can be useful if you want to use
+    your own custom country boundaries.
+
+
+### Customizing the main processing function
+
+The main processing function of the flex style can be found in the function
+`process_tags`. This function is called for all OSM object kinds and is
+responsible for filtering the tags and writing out the rows into Postgresql.
+
+!!! Example
+    ``` lua
+    local flex = require('import-full')
+
+    local original_process_tags = flex.process_tags
+
+    function flex.process_tags(o)
+        if o.object.tags.highway ~= nil and o.object.tags.access == 'no' then
+            return
+        end
+
+        original_process_tags(o)
+    end
+    ```
+
+    This example shows the most simple customization of the process_tags function.
+    It simply adds some additional processing before running the original code.
+    To do that, first save the original function and then overwrite process_tags
+    from the module. In this example all highways which are not accessible
+    by anyone will be ignored.
+
+
+#### The `Place` class
+
+The `process_tags` function receives a Lua object of `Place` type which comes
+with some handy functions to collect the data necessary for geocoding and
+writing it into the place table. Always use this object to fill the table.
+
+The Place class has some attributes which you may access read-only:
+
+* __object__ is the original OSM object data handed in by osm2pgsql
+* __admin_level__ is the content of the admin_level tag, parsed into an
+  integer and normalized to a value between 0 and 15
+* __has_name__ is a boolean indicating if the object has a full name
+* __names__ is a table with the collected list of name tags
+* __address__ is a table with the collected list of address tags
+* __extratags__ is a table with the collected list of additional tags to save
+
+There are a number of functions to fill these fields. All functions expect
+a table parameter with fields as indicated in the description.
+Many of these functions expect match functions which are described in detail
+further below.
+
+* __delete{match=...}__ removes all tags that match the match function given
+  in _match_.
+* __grab_extratags{match=...}__ moves all tags that match the match function
+  given in _match_ into extratags. Returns the number of tags moved.
+* __clean{delete=..., extra=...}__ deletes all tags that match _delete_ and
+  moves the ones that match _extra_  into extratags
+* __grab_address_parts{groups=...}__ moves matching tags into the address table.
+  _groups_ must be a group match function. Tags of the group `main` and
+  `extra` are added to the address table as is but with `addr:` and `is_in:`
+  prefixes removed from the tag key. All other groups are added with the
+  group name as key and the value from the tag. Multiple values of the same
+  group overwrite each other. The function returns the number of tags saved
+  from the main group.
+* __grab_main_parts{groups=...}__ moves matching tags into the name table.
+  _groups_ must be a group match function. If a tags of the group `main` is
+  present, the object will be marked as having a name. Tags of group `house`
+  produce a fallback to `place=house`. This fallback is return by the function
+  if present.
+
+There are two functions to write a row into the place table. Both functions
+expect the main tag (key and value) for the row and then use the collected
+information from the name, address, extratags etc. fields to complete the row.
+They also have a boolean parameter `save_extra_mains` which defines how any
+unprocessed tags are handled: when True, the tags will be saved as extratags,
+when False, they will be simply discarded.
+
+* __write_row(key, value, save_extra_mains)__ creates a new table row from
+  the current state of the Place object.
+* __write_place(key, value, mtype, save_extra_mains)__ creates a new row
+  conditionally. When value is nil, the function will attempt to look up the
+  value in the object tags. If value is still nil or mtype is nil, the row
+  is ignored. An mtype of `always` will then always write out the row,
+  a mtype of `named` only, when the object has a full name. When mtype
+  is `named_with_key`, the function checks for a domain name, i.e. a name
+  tag prefixed with the name of the main key. Only if at least one is found,
+  the row will be written. The names are replaced with the domain names found.
+
+#### Match functions
+
+The Place functions usually expect either a _match function_ or a
+_group match function_ to find the tags to apply their function to.
+
+The __match function__ is a Lua function which takes two parameters,
+key and value, and returns a boolean to indicate that a tag matches. The
+flex-base module has a convenience function `tag_match()` to create such a
+function. It takes a table with two optional fields: `keys` takes a key match
+list (see above), `tags` takes a table with keys that point to a list of
+possible values, thus defining key/value matches.
+
+The __group match function__ is a Lua function which also takes two parameters,
+key and value, and returns a string indicating to which group or type they
+belong to. The `tag_group()` can be used to create such a function. It expects
+a table where the group names are the keys and the values are a key match list.
+
+
+
+### Using the gazetteer output of osm2pgsql
+
+Nominatim still allows you to configure the gazetteer output to remain
+backwards compatible with older imports. It will be automatically used
+when the style file name ends in `.style`. For documentation of the
+old import style, please refer to the documentation of older releases
+of Nominatim. Do not use the gazetteer output for new imports. There is no
+guarantee that new versions of Nominatim are fully compatible with the
+gazetteer output.
 
 ### Changing the Style of Existing Databases
 

docs/customize/SQLite.md

@@ -0,0 +1,55 @@
+A Nominatim database can be converted into an SQLite database and used as
+a read-only source for geocoding queries. This sections describes how to
+create and use an SQLite database.
+
+!!! danger
+    This feature is in an experimental state at the moment. Use at your own
+    risk.
+
+## Installing prerequisites
+
+To use a SQLite database, you need to install:
+
+* SQLite (>= 3.30)
+* Spatialite (> 5.0.0)
+
+On Ubuntu/Debian, you can run:
+
+    sudo apt install sqlite3 libsqlite3-mod-spatialite libspatialite7
+
+## Creating a new SQLite database
+
+Nominatim cannot import directly into SQLite database. Instead you have to
+first create a geocoding database in PostgreSQL by running a
+[regular Nominatim import](../admin/Import.md).
+
+Once this is done, the database can be converted to SQLite with
+
+    nominatim convert -o mydb.sqlite
+
+This will create a database where all geocoding functions are available.
+Depending on what functions you need, the database can be made smaller:
+
+* `--without-reverse` omits indexes only needed for reverse geocoding
+* `--without-search` omit tables and indexes used for forward search
+* `--without-details` leaves out extra information only available in the
+  details API
+
+## Using an SQLite database
+
+Once you have created the database, you can use it by simply pointing the
+database DSN to the SQLite file:
+
+    NOMINATIM_DATABASE_DSN=sqlite:dbname=mydb.sqlite
+
+Please note that SQLite support is only available for the Python frontend. To
+use the test server with an SQLite database, you therefore need to switch
+the frontend engine:
+
+    nominatim serve --engine falcon
+
+You need to install falcon or starlette for this, depending on which engine
+you choose.
+
+The CLI query commands and the library interface already use the new Python
+frontend and therefore work right out of the box.

docs/customize/Settings.md

@@ -91,7 +91,7 @@ The option is only used by the Legacy tokenizer and ignored otherwise.
 | --------------     | --------------------------------------------------- |
 | **Description:**   | Tokenizer used for normalizing and parsing queries and names |
 | **Format:**        | string |
-| **Default:**       | legacy |
+| **Default:**       | icu |
 | **After Changes:** | cannot be changed after import |
 
 Sets the tokenizer type to use for the import. For more information on
@@ -148,29 +148,6 @@ Setting this option to 'yes' means that Nominatim skips reindexing of contained
 objects when the area becomes too large.
 
 
-#### NOMINATIM_UPDATE_FORWARD_DEPENDENCIES
-
-| Summary            |                                                     |
-| --------------     | --------------------------------------------------- |
-| **Description:**   | Forward geometry changes to dependet objects |
-| **Format:**        | bool |
-| **Default:**       | no |
-| **Comment:**       | EXPERT ONLY. Must not be enabled after import. |
-
-The geometry of OSM ways and relations may change when a node that is part
-of the object is moved around. These changes are not propagated per default.
-The geometry of ways/relations is only updated the next time that the object
-itself is touched. When enabling this option, then dependent objects will
-be marked for update when one of its member objects changes.
-
-Enabling this option may slow down updates significantly.
-
-!!! warning
-    If you want to enable this option, it must be set already on import.
-    Do not enable this option on an existing database that was imported with
-    NOMINATIM_UPDATE_FORWARD_DEPENDENCIES=no.
-    Updates will become unusably slow.
-
 #### NOMINATIM_LANGUAGES
 
 | Summary            |                                                     |
@@ -575,6 +552,8 @@ used.
 | **Format:**        | boolean |
 | **Default:**       | no |
 | **After Changes:** | run `nominatim refresh --website` |
+| **Comment:**       | PHP frontend only |
+
 
 This feature is currently undocumented and potentially broken.
 
@@ -587,6 +566,7 @@ This feature is currently undocumented and potentially broken.
 | **Format:**        | integer |
 | **Default:**       | 500 |
 | **After Changes:** | run `nominatim refresh --website` |
+| **Comment:**       | PHP frontend only |
 
 This setting defines the threshold over which a name is no longer considered
 as rare. When searching for places with rare names, only the name is used
@@ -627,6 +607,88 @@ with a single query.
 
 Setting this parameter to 0 disables polygon output completely.
 
+
+#### NOMINATIM_SEARCH_WITHIN_COUNTRIES
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Disable search for elements that are not in the country grid |
+| **Format:**        | boolean |
+| **Default:**       | no |
+| **After Changes:** | run `nominatim refresh --website` |
+| **Comment:**       | PHP frontend only |
+
+Enable to search elements just within countries.
+
+When enabled, if, despite not finding a point within the static grid of countries, it
+finds a geometry of a region, do not return the geometry.
+Return "Unable to geocode" instead.
+
+
+#### NOMINATIM_SERVE_LEGACY_URLS
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Enable serving via URLs with a .php suffix |
+| **Format:**        | boolean |
+| **Default:**       | yes |
+| **Comment:**       | Python frontend only |
+
+When enabled, then endpoints are reachable as `/<name>` as well as `/<name>.php`.
+This can be useful when you want to be backwards-compatible with previous
+versions of Nominatim.
+
+
+#### NOMINATIM_API_POOL_SIZE
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Number of parallel database connections per worker |
+| **Format:**        | number |
+| **Default:**       | 10 |
+| **Comment:**       | Python frontend only |
+
+Sets the maximum number of database connections available for a single instance
+of Nominatim. When configuring the maximum number of connections that your
+PostgreSQL database can handle, you need at least
+`NOMINATIM_API_POOL_SIZE` * `<number of configured workers>` connections.
+For configuring the number of workers, refer to the section about
+[Deploying the Python frontend](../admin/Deployment-Python.md).
+
+#### NOMINATIM_QUERY_TIMEOUT
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Timeout for SQL queries to the database |
+| **Format:**        | number (seconds) |
+| **Default:**       | 10 |
+| **Comment:**       | Python frontend only |
+
+When this timeout is set, then all SQL queries that run longer than the
+specified numbers of seconds will be cancelled and the user receives a
+timeout exceptions. Users of the API see a 503 HTTP error.
+
+The timeout does ont apply when using the
+[low-level DB access](../library/Low-Level-DB-Access.md)
+of the library. A timeout can be manually set, if required.
+
+
+#### NOMINATIM_REQUEST_TIMEOUT
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Timeout for search queries |
+| **Format:**        | number (seconds) |
+| **Default:**       | 60 |
+| **Comment:**       | Python frontend only |
+
+When this timeout is set, a search query will finish sending queries
+to the database after the timeout has passed and immediately return the
+results gathered so far.
+
+Note that under high load you may observe that users receive different results
+than usual without seeing an error. This may cause some confusion.
+
 ### Logging Settings
 
 #### NOMINATIM_LOG_DB
@@ -670,3 +732,20 @@ given in seconds and corresponds to the time the query took executing in PHP.
 type contains the name of the endpoint used.
 
 Can be used as the same time as NOMINATIM_LOG_DB.
+
+#### NOMINATIM_DEBUG_SQL
+
+| Summary            |                                                     |
+| --------------     | --------------------------------------------------- |
+| **Description:**   | Enable printing of raw SQL by SQLAlchemy |
+| **Format:**        | boolean |
+| **Default:**       | no |
+| **Comment:**       | **For developers only.** |
+
+This settings enables
+[SQL debugging](https://docs.sqlalchemy.org/en/20/core/engines.html#dbengine-logging)
+by SQLAlchemy. This can be helpful when debugging some bugs with internal
+query handling. It should only be used together with the CLI query functions.
+Enabling it for server mode may have unintended consequences. Use the `debug`
+parameter instead, which prints information on how the search is executed
+including SQL statements.

docs/customize/Tokenizers.md

@@ -102,7 +102,7 @@ Here is an example configuration file:
 ``` yaml
 normalization:
     - ":: lower ()"
-    - "ß > 'ss'" # German szet is unimbigiously equal to double ss
+    - "ß > 'ss'" # German szet is unambiguously equal to double ss
 transliteration:
     - !include /etc/nominatim/icu-rules/extended-unicode-to-asccii.yaml
     - ":: Ascii ()"
@@ -128,7 +128,7 @@ The configuration file contains four sections:
 The normalization and transliteration sections each define a set of
 ICU rules that are applied to the names.
 
-The **normalisation** rules are applied after sanitation. They should remove
+The **normalization** rules are applied after sanitation. They should remove
 any information that is not relevant for search at all. Usual rules to be
 applied here are: lower-casing, removing of special characters, cleanup of
 spaces.
@@ -176,52 +176,66 @@ The following is a list of sanitizers that are shipped with Nominatim.
 ##### split-name-list
 
 ::: nominatim.tokenizer.sanitizers.split_name_list
-    selection:
+    options:
         members: False
-    rendering:
         heading_level: 6
+        docstring_section_style: spacy
 
 ##### strip-brace-terms
 
 ::: nominatim.tokenizer.sanitizers.strip_brace_terms
-    selection:
+    options:
         members: False
-    rendering:
         heading_level: 6
+        docstring_section_style: spacy
 
 ##### tag-analyzer-by-language
 
 ::: nominatim.tokenizer.sanitizers.tag_analyzer_by_language
-    selection:
+    options:
         members: False
-    rendering:
         heading_level: 6
+        docstring_section_style: spacy
 
 ##### clean-housenumbers
 
 ::: nominatim.tokenizer.sanitizers.clean_housenumbers
-    selection:
+    options:
         members: False
-    rendering:
         heading_level: 6
+        docstring_section_style: spacy
 
 ##### clean-postcodes
 
 ::: nominatim.tokenizer.sanitizers.clean_postcodes
-    selection:
+    options:
         members: False
-    rendering:
         heading_level: 6
+        docstring_section_style: spacy
 
 ##### clean-tiger-tags
 
 ::: nominatim.tokenizer.sanitizers.clean_tiger_tags
-    selection:
+    options:
         members: False
-    rendering:
         heading_level: 6
+        docstring_section_style: spacy
 
+#### delete-tags
 
+::: nominatim.tokenizer.sanitizers.delete_tags
+    options:
+        members: False
+        heading_level: 6
+        docstring_section_style: spacy
+
+#### tag-japanese
+
+::: nominatim.tokenizer.sanitizers.tag_japanese
+    options:
+        members: False
+        heading_level: 6
+        docstring_section_style: spacy
 
 #### Token Analysis
 
@@ -380,7 +394,7 @@ The analyzer cannot be customized.
 ##### Postcode token analyzer
 
 The analyzer `postcodes` is pupose-made to analyze postcodes. It supports
-a 'lookup' varaint of the token, which produces variants with optional
+a 'lookup' variant of the token, which produces variants with optional
 spaces. Use together with the clean-postcodes sanitizer.
 
 The analyzer cannot be customized.

docs/develop/Development-Environment.md

@@ -36,12 +36,19 @@ It has the following additional requirements:
 * [mypy](http://mypy-lang.org/) (plus typing information for external libs)
 * [Python Typing Extensions](https://github.com/python/typing_extensions) (for Python < 3.9)
 * [pytest](https://pytest.org)
+* [pytest-asyncio](https://pytest-asyncio.readthedocs.io)
+
+For testing the Python search frontend, you need to install extra dependencies
+depending on your choice of webserver framework:
+
+* [httpx](https://www.python-httpx.org/) (starlette only)
+* [asgi-lifespan](https://github.com/florimondmanca/asgi-lifespan) (starlette only)
 
 The documentation is built with mkdocs:
 
 * [mkdocs](https://www.mkdocs.org/) >= 1.1.2
-* [mkdocstrings](https://mkdocstrings.github.io/) >= 0.16
-* [mkdocstrings-python-legacy](https://mkdocstrings.github.io/python-legacy/)
+* [mkdocstrings](https://mkdocstrings.github.io/) >= 0.18
+* [mkdocstrings-python](https://mkdocstrings.github.io/python/)
 
 ### Installing prerequisites on Ubuntu/Debian
 
@@ -55,8 +62,10 @@ To install all necessary packages run:
 sudo apt install php-cgi phpunit php-codesniffer \
                  python3-pip python3-setuptools python3-dev
 
-pip3 install --user behave mkdocs mkdocstrings pytest pylint \
-                    mypy types-PyYAML types-jinja2 types-psycopg2 types-psutil
+pip3 install --user behave mkdocs mkdocstrings pytest pytest-asyncio pylint \
+                    mypy types-PyYAML types-jinja2 types-psycopg2 types-psutil \
+                    types-ujson types-requests types-Pygments typing-extensions\
+                    httpx asgi-lifespan
 ```
 
 The `mkdocs` executable will be located in `.local/bin`. You may have to add

docs/develop/ICU-Tokenizer-Modules.md

@@ -53,8 +53,7 @@ the function.
 ### Sanitizer configuration
 
 ::: nominatim.tokenizer.sanitizers.config.SanitizerConfig
-    rendering:
-        show_source: no
+    options:
         heading_level: 6
 
 ### The main filter function of the sanitizer
@@ -62,12 +61,10 @@ the function.
 The filter function receives a single object of type `ProcessInfo`
 which has with three members:
 
- * `place`: read-only information about the place being processed.
+ * `place: PlaceInfo`: read-only information about the place being processed.
    See PlaceInfo below.
- * `names`: The current list of names for the place. Each name is a
-   PlaceName object.
- * `address`: The current list of address names for the place. Each name
-   is a PlaceName object.
+ * `names: List[PlaceName]`: The current list of names for the place.
+ * `address: List[PlaceName]`: The current list of address names for the place.
 
 While the `place` member is provided for information only, the `names` and
 `address` lists are meant to be manipulated by the sanitizer. It may add and
@@ -77,16 +74,14 @@ adding extra attributes) or completely replace the list with a different one.
 #### PlaceInfo - information about the place
 
 ::: nominatim.data.place_info.PlaceInfo
-    rendering:
-        show_source: no
+    options:
         heading_level: 6
 
 
 #### PlaceName - extended naming information
 
 ::: nominatim.data.place_name.PlaceName
-    rendering:
-        show_source: no
+    options:
         heading_level: 6
 
 
@@ -134,7 +129,7 @@ sanitizers:
 !!! warning
     This example is just a simplified show case on how to create a sanitizer.
     It is not really read for real-world use: while the sanitizer would
-    correcly transform `West 5th Street` into `5th Street`. it would also
+    correctly transform `West 5th Street` into `5th Street`. it would also
     shorten a simple `North Street` to `Street`.
 
 For more sanitizer examples, have a look at the sanitizers provided by Nominatim.
@@ -145,14 +140,12 @@ They can be found in the directory
 ## Custom token analysis module
 
 ::: nominatim.tokenizer.token_analysis.base.AnalysisModule
-    rendering:
-        show_source: no
+    options:
         heading_level: 6
 
 
 ::: nominatim.tokenizer.token_analysis.base.Analyzer
-    rendering:
-        show_source: no
+    options:
         heading_level: 6
 
 ### Example: Creating acronym variants for long names

docs/develop/Testing.md

@@ -10,7 +10,7 @@ There are two kind of tests in this test suite. There are functional tests
 which test the API interface using a BDD test framework and there are unit
 tests for specific PHP functions.
 
-This test directory is sturctured as follows:
+This test directory is structured as follows:
 
 ```
  -+-   bdd         Functional API tests
@@ -84,6 +84,8 @@ The tests can be configured with a set of environment variables (`behave -D key=
  * `TEST_DB` - name of test database (db tests)
  * `API_TEST_DB` - name of the database containing the API test data (api tests)
  * `API_TEST_FILE` - OSM file to be imported into the API test database (api tests)
+ * `API_ENGINE` - webframe to use for running search queries, same values as
+                  `nominatim serve --engine` parameter
  * `DB_HOST` - (optional) hostname of database host
  * `DB_PORT` - (optional) port of database on host
  * `DB_USER` - (optional) username of database login
@@ -120,7 +122,7 @@ and compromises the following data:
 API tests should only be testing the functionality of the website PHP code.
 Most tests should be formulated as BDD DB creation tests (see below) instead.
 
-#### Code Coverage
+#### Code Coverage (PHP engine only)
 
 The API tests also support code coverage tests. You need to install
 [PHP_CodeCoverage](https://github.com/sebastianbergmann/php-code-coverage).
@@ -153,7 +155,3 @@ needs superuser rights for postgres.
 
 These tests check that data is imported correctly into the place table. They
 use the same template database as the DB Creation tests, so the same remarks apply.
-
-Note that most testing of the gazetteer output of osm2pgsql is done in the tests
-of osm2pgsql itself. The BDD tests are just there to ensure compatibility of
-the osm2pgsql and Nominatim code.

docs/develop/Tokenizers.md

@@ -134,14 +134,14 @@ All tokenizers must inherit from `nominatim.tokenizer.base.AbstractTokenizer`
 and implement the abstract functions defined there.
 
 ::: nominatim.tokenizer.base.AbstractTokenizer
-    rendering:
-        heading_level: 4
+    options:
+        heading_level: 6
 
 ### Python Analyzer Class
 
 ::: nominatim.tokenizer.base.AbstractAnalyzer
-    rendering:
-        heading_level: 4
+    options:
+        heading_level: 6
 
 ### PL/pgSQL Functions
 
@@ -189,6 +189,28 @@ a house number token text. If a place has multiple house numbers they must
 be listed with a semicolon as delimiter. Must be NULL when the place has no
 house numbers.
 
+```sql
+FUNCTION token_is_street_address(info JSONB) RETURNS BOOLEAN
+```
+
+Return true if this is an object that should be parented against a street.
+Only relevant for objects with address rank 30.
+
+```sql
+FUNCTION token_has_addr_street(info JSONB) RETURNS BOOLEAN
+```
+
+Return true if there are street names to match against for finding the
+parent of the object.
+
+
+```sql
+FUNCTION token_has_addr_place(info JSONB) RETURNS BOOLEAN
+```
+
+Return true if there are place names to match against for finding the
+parent of the object.
+
 ```sql
 FUNCTION token_matches_street(info JSONB, street_tokens INTEGER[]) RETURNS BOOLEAN
 ```

docs/develop/parenting-flow.plantuml

@@ -18,7 +18,7 @@ elseif (has 'addr:place'?) then (yes)
      **with same name**;
      kill
   else (no)
-    :add addr:place to adress;
+    :add addr:place to address;
     :**Use closest place**\n**rank 16 to 25**;
      kill
   endif

docs/extra.css

@@ -2,6 +2,10 @@
     display: none!important
 }
 
+.wy-nav-content {
+    max-width: 900px!important
+}
+
 table {
     margin-bottom: 12pt
 }
@@ -16,9 +20,17 @@ th {
 
 .doc-object h6 {
     margin-bottom: 0.8em;
-    font-size: 120%;
+    font-size: 130%;
 }
 
 .doc-object {
     margin-bottom: 1.3em;
 }
+
+.doc-children .doc-contents {
+    margin-left: 3em;
+}
+
+.md-footer__inner {
+    display: none;
+}

docs/index.md

@@ -1,10 +1,15 @@
-Nominatim (from the Latin, 'by name') is a tool to search OSM data by name and address and to generate synthetic addresses of OSM points (reverse geocoding).
+Nominatim (from the Latin, 'by name') is a tool to search OSM data by name and
+address and to generate synthetic addresses of OSM points (reverse geocoding).
+It has also limited capability to search features by their type
+(pubs, hotels, churches, etc).
 
-This guide comes in four parts:
+This guide comes in five parts:
 
  * __[API reference](api/Overview.md)__ for users of Nominatim
  * __[Administration Guide](admin/Installation.md)__ for those who want
    to install their own Nominatim server
  * __[Customization Guide](customize/Overview.md)__ for those who want to
    adapt their own installation to their special requirements
+ * __[Library Guide](library/Getting-Started.md)__ for Python developers who
+   want to use Nominatim as a library in their project
  * __[Developer's Guide](develop/overview.md)__ for developers of the software

docs/library/Configuration.md

@@ -0,0 +1,31 @@
+# Configuration
+
+When using Nominatim through the library, it can be configured in exactly
+the same way as when running as a service. This means that you should have
+created a [project directory](../admin/Import.md#creating-the-project-directory)
+which contains all files belonging to the Nominatim instance. It can also contain
+an `.env` file with configuration options. Setting configuration parameters
+via environment variables works as well.
+
+Configuration options are resolved in the following order:
+
+* from the OS environment (or the dictionary given in `environ`,
+  (see NominatimAPI.md#nominatim.api.core.NominatimAPI.__init__)
+* from the .env file in the project directory of the installation
+* from the default installation in the configuration directory
+
+For more information on configuration via dotenv and a list of possible
+configuration parameters, see the [Configuration page](../customize/Settings.md).
+
+
+## `Configuration` class
+
+::: nominatim.config.Configuration
+    options:
+        members:
+            - get_bool
+            - get_int
+            - get_str_list
+            - get_path
+        heading_level: 6
+        show_signature_annotations: True

docs/library/Getting-Started.md

@@ -0,0 +1,248 @@
+# Getting Started
+
+The Nominatim search frontend can directly be used as a Python library in
+scripts and applications. When you have imported your own Nominatim database,
+then it is no longer necessary to run a full web service for it and access
+the database through http requests. There are
+also less constraints on the kinds of data that can be accessed. The library
+allows to get access to more detailed information about the objects saved
+in the database.
+
+!!! danger
+    The library interface is currently in an experimental stage. There might
+    be some smaller adjustments to the public interface until the next version.
+
+    The library also misses a proper installation routine, so some manipulation
+    of the PYTHONPATH is required. At the moment, use is only recommended for
+    developers with some experience in Python.
+
+## Installation
+
+To use the Nominatim library, you need access to a local Nominatim database.
+Follow the [installation](../admin/Installation.md) and
+[import](../admin/Import.md) instructions to set up your database.
+
+It is not yet possible to install it in the usual way via pip or inside a
+virtualenv. To get access to the library you need to set an appropriate
+`PYTHONPATH`. With the default installation, the python library can be found
+under `/usr/local/share/nominatim/lib-python`. If you have installed
+Nominatim under a different prefix, adapt the `/usr/local/` part accordingly.
+You can also point the `PYTHONPATH` to the Nominatim source code.
+
+### A simple search example
+
+To query the Nominatim database you need to first set up a connection. This
+is done by creating an Nominatim API object. This object exposes all the
+search functions of Nominatim that are also known from its web API.
+
+This code snippet implements a simple search for the town of 'Brugge':
+
+!!! example
+    === "NominatimAPIAsync"
+        ``` python
+        from pathlib import Path
+        import asyncio
+
+        import nominatim.api as napi
+
+        async def search(query):
+            api = napi.NominatimAPIAsync(Path('.'))
+
+            return await api.search(query)
+
+        results = asyncio.run(search('Brugge'))
+        if not results:
+            print('Cannot find Brugge')
+        else:
+            print(f'Found a place at {results[0].centroid.x},{results[0].centroid.y}')
+        ```
+
+    === "NominatimAPI"
+        ``` python
+        from pathlib import Path
+
+        import nominatim.api as napi
+
+        api = napi.NominatimAPI(Path('.'))
+
+        results = api.search('Brugge')
+
+        if not results:
+            print('Cannot find Brugge')
+        else:
+            print(f'Found a place at {results[0].centroid.x},{results[0].centroid.y}')
+        ```
+
+The Nominatim library is designed around
+[asyncio](https://docs.python.org/3/library/asyncio.html). `NominatimAPIAsync`
+provides you with an interface of coroutines.
+If you have many requests to make, coroutines can speed up your applications
+significantly.
+
+For smaller scripts there is also a synchronous wrapper around the API. By
+using `NominatimAPI`, you get exactly the same interface using classic functions.
+
+The examples in this chapter will always show-case both
+implementations. The documentation itself will usually refer only to
+'Nominatim API class' when both flavours are meant. If a functionality is
+available only for the synchronous or asynchronous version, this will be
+explicitly mentioned.
+
+### Defining which database to use
+
+The [Configuration](../admin/Import.md#configuration-setup-in-env)
+section explains how Nominatim is configured using the
+[dotenv](https://github.com/theskumar/python-dotenv) library.
+The same configuration mechanism is used with the
+Nominatim API library. You should therefore be sure you are familiar with
+the section.
+
+The constructor of the 'Nominatim API class' takes one mandatory parameter:
+the path to the [project directory](../admin/Import.md#creating-the-project-directory).
+You should have set up this directory as part of the Nominatim import.
+Any configuration found in the `.env` file in this directory will automatically
+used.
+
+Yo may also configure Nominatim be setting environment variables.
+Normally, Nominatim will check the operating system environment. This can be
+overwritten by giving the constructor a dictionary of configuration parameters.
+
+Let us look up 'Brugge' in the special database named 'belgium' instead of the
+standard 'nominatim' database:
+
+!!! example
+    === "NominatimAPIAsync"
+        ``` python
+        from pathlib import Path
+        import asyncio
+
+        import nominatim.api as napi
+
+        config_params = {
+            'NOMINATIM_DATABASE_DSN': 'pgsql:dbname=belgium'
+        }
+
+        async def search(query):
+            api = napi.NominatimAPIAsync(Path('.'), environ=config_params)
+
+            return await api.search(query)
+
+        results = asyncio.run(search('Brugge'))
+        ```
+
+    === "NominatimAPI"
+        ``` python
+        from pathlib import Path
+
+        import nominatim.api as napi
+
+        config_params = {
+            'NOMINATIM_DATABASE_DSN': 'pgsql:dbname=belgium'
+        }
+
+        api = napi.NominatimAPI(Path('.'), environ=config_params)
+
+        results = api.search('Brugge')
+        ```
+
+### Presenting results to humans
+
+All search functions return the raw results from the database. There is no
+full human-readable label. To create such a label, you need two things:
+
+* the address details of the place
+* adapt the result to the language you wish to use for display
+
+Again searching for 'Brugge', this time with a nicely formatted result:
+
+!!! example
+    === "NominatimAPIAsync"
+        ``` python
+        from pathlib import Path
+        import asyncio
+
+        import nominatim.api as napi
+
+        async def search(query):
+            api = napi.NominatimAPIAsync(Path('.'))
+
+            return await api.search(query, address_details=True)
+
+        results = asyncio.run(search('Brugge'))
+
+        locale = napi.Locales(['fr', 'en'])
+        for i, result in enumerate(results):
+            address_parts = result.address_rows.localize(locale)
+            print(f"{i + 1}. {', '.join(address_parts)}")
+        ```
+
+    === "NominatimAPI"
+        ``` python
+        from pathlib import Path
+
+        import nominatim.api as napi
+
+        api = napi.NominatimAPI(Path('.'))
+
+        results = api.search('Brugge', address_details=True)
+
+        locale = napi.Locales(['fr', 'en'])
+        for i, result in enumerate(results):
+            address_parts = result.address_rows.localize(locale)
+            print(f"{i + 1}. {', '.join(address_parts)}")
+        ```
+
+To request information about the address of a result, add the optional
+parameter 'address_details' to your search:
+
+``` python
+>>> results = api.search('Brugge', address_details=True)
+```
+
+An additional field `address_rows` will set in results that are returned.
+It contains a list of all places that make up the address of the place. For
+simplicity, this includes name and house number of the place itself. With
+the names in this list it is possible to create a human-readable description
+of the result. To do that, you first need to decide in which language the
+results should be presented. As with the names in the result itself, the
+places in `address_rows` contain all possible name translation for each row.
+
+The library has a helper class `Locale` which helps extracting a name of a
+place in the preferred language. It takes a single parameter with a list
+of language codes in the order of preference. So
+
+``` python
+locale = napi.Locale(['fr', 'en'])
+```
+
+creates a helper class that returns the name preferably in French. If that is
+not possible, it tries English and eventually falls back to the default `name`
+or `ref`.
+
+The `Locale` object can be applied to a name dictionary to return the best-matching
+name out of it:
+
+``` python
+>>> print(locale.display_name(results[0].names))
+'Brugges'
+```
+
+The `address_row` field has a helper function to apply the function to all
+its members and save the result in the `local_name` field. It also returns
+all the localized names as a convenient simple list. This list can be used
+to create a human-readable output:
+
+``` python
+>>> address_parts = results[0].address_rows.localize(locale)
+>>> print(', '.join(address_parts))
+Bruges, Flandre-Occidentale, Flandre, Belgique
+```
+
+This is a fairly simple way to create a human-readable description. The
+place information in `address_rows` contains further information about each
+place. For example, which OSM `adlin_level` was used, what category the place
+belongs to or what rank Nominatim has assigned. Use this to adapt the output
+to local address formats.
+
+For more information on address rows, see
+[detailed address description](Result-Handling.md#detailed-address-description).

docs/library/Input-Parameter-Types.md

@@ -0,0 +1,62 @@
+# Input Parameter Types
+
+This page describes in more detail some of the input parameter types used
+in the query functions of the API object.
+
+## Place identification
+
+The [details](NominatimAPI.md#nominatim.api.core.NominatimAPI.details) and
+[lookup](NominatimAPI.md#nominatim.api.core.NominatimAPI.lookup) functions
+require references to places in the database. Below the possible
+types for place identification are listed. All types are dataclasses.
+
+### PlaceID
+
+::: nominatim.api.PlaceID
+    options:
+        heading_level: 6
+
+### OsmID
+
+::: nominatim.api.OsmID
+    options:
+        heading_level: 6
+
+## Geometry types
+
+::: nominatim.api.GeometryFormat
+    options:
+        heading_level: 6
+        members_order: source
+
+## Geometry input
+
+### Point
+
+::: nominatim.api.Point
+    options:
+        heading_level: 6
+        show_signature_annotations: True
+
+### Bbox
+
+::: nominatim.api.Bbox
+    options:
+        heading_level: 6
+        show_signature_annotations: True
+        members_order: source
+        group_by_category: False
+
+## Layers
+
+Layers allow to restrict the search result to thematic groups. This is
+orthogonal to restriction by address ranks, which groups places by their
+geographic extent.
+
+
+::: nominatim.api.DataLayer
+    options:
+        heading_level: 6
+        members_order: source
+
+

docs/library/Low-Level-DB-Access.md

@@ -0,0 +1,56 @@
+# Low-level connections
+
+The `NominatimAPIAsync` class allows to directly access the underlying
+database connection to explore the raw data. Nominatim uses
+[SQLAlchemy](https://docs.sqlalchemy.org/) for building queries. Please
+refer to the documentation of the library to understand how to write SQL.
+
+To get access to a search connection, use the `begin()` function of your
+API object. This returns a `SearchConnection` object described below
+wrapped in a context manager. Its
+`t` property has definitions for all Nominatim search tables. For an
+overview of available tables, refer to the
+[Development Layout](../develop/Database-Layout.md) in in the development
+chapter. Note that only tables that are needed for search are accessible
+as SQLAlchemy tables.
+
+!!! warning
+    The database layout is not part of the API definition and may change
+    without notice. If you play with the low-level access functions, you
+    need to be prepared for such changes.
+
+Here is a simple example, which prints how many places are available in
+the placex table:
+
+```
+import asyncio
+from pathlib import Path
+import sqlalchemy as sa
+from nominatim.api import NominatimAPIAsync
+
+async def print_table_size():
+    api = NominatimAPIAsync(Path('.'))
+
+    async with api.begin() as conn:
+        cnt = await conn.scalar(sa.select(sa.func.count()).select_from(conn.t.placex))
+        print(f'placex table has {cnt} rows.')
+
+asyncio.run(print_table_size())
+```
+
+!!! warning
+    Low-level connections may only be used to read data from the database.
+    Do not use it to add or modify data or you might break Nominatim's
+    normal functions.
+
+## SearchConnection class
+
+::: nominatim.api.SearchConnection
+    options:
+        members:
+            - scalar
+            - execute
+            - get_class_table
+            - get_db_property
+            - get_property
+        heading_level: 6

docs/library/NominatimAPI.md

@@ -0,0 +1,36 @@
+# The Nominatim API classes
+
+The API classes are the core object of the search library. Always instantiate
+one of these classes first. The API classes are **not threadsafe**. You need
+to instantiate a separate instance for each thread.
+
+### NominatimAPI
+
+::: nominatim.api.NominatimAPI
+    options:
+        members:
+            - __init__
+            - config
+            - close
+            - status
+            - details
+            - lookup
+            - reverse
+            - search
+            - search_address
+            - search_category
+        heading_level: 6
+        group_by_category: False
+
+
+### NominatimAPIAsync
+
+::: nominatim.api.NominatimAPIAsync
+    options:
+        members:
+            - __init__
+            - setup_database
+            - close
+            - begin
+        heading_level: 6
+        group_by_category: False

docs/library/Result-Handling.md

@@ -0,0 +1,58 @@
+# Result handling
+
+The search functions of the Nominatim API always return a result object
+with the raw information about the place that is available in the
+database. This section discusses data types used in the results and utility
+functions that allow further processing of the results.
+
+## Result fields
+
+### Sources
+
+Nominatim takes the result data from multiple sources. The `source_table` field
+in the result describes, from which source the result was retrieved.
+
+::: nominatim.api.SourceTable
+    options:
+        heading_level: 6
+        members_order: source
+
+### Detailed address description
+
+When the `address_details` parameter is set, then functions return not
+only information about the result place but also about the place that
+make up the address. This information is almost always required when you
+want to present the user with a human-readable description of the result.
+See also [Localization](#localization) below.
+
+The address details are available in the `address_rows` field as a ordered
+list of `AddressLine` objects with the country information last. The list also
+contains the result place itself and some artificial entries, for example,
+for the house number or the country code. This makes processing and creating
+a full address easier.
+
+::: nominatim.api.AddressLine
+    options:
+        heading_level: 6
+        members_order: source
+
+### Detailed search terms
+
+The `details` function can return detailed information about which search terms
+may be used to find a place, when the `keywords` parameter is set. Search
+terms are split into terms for the name of the place and search terms for
+its address.
+
+::: nominatim.api.WordInfo
+    options:
+        heading_level: 6
+
+## Localization
+
+Results are always returned with the full list of available names.
+
+### Locale
+
+::: nominatim.api.Locales
+    options:
+        heading_level: 6

docs/mkdocs.yml

@@ -1,5 +1,9 @@
-site_name: Nominatim Documentation
-theme: readthedocs
+site_name: Nominatim Manual
+theme:
+  name: material
+  features:
+    - navigation.tabs
+copyright: Copyright © Nominatim developer community
 docs_dir: ${CMAKE_CURRENT_BINARY_DIR}
 site_url: https://nominatim.org
 repo_url: https://github.com/openstreetmap/Nominatim
@@ -18,7 +22,8 @@ nav:
         - 'Basic Installation': 'admin/Installation.md'
         - 'Import' : 'admin/Import.md'
         - 'Update' : 'admin/Update.md'
-        - 'Deploy' : 'admin/Deployment.md'
+        - 'Deploy (Python frontend)' : 'admin/Deployment-Python.md'
+        - 'Deploy (PHP frontend)' : 'admin/Deployment-PHP.md'
         - 'Nominatim UI'  : 'admin/Setup-Nominatim-UI.md'
         - 'Advanced Installations' : 'admin/Advanced-Installations.md'
         - 'Maintenance' : 'admin/Maintenance.md'
@@ -35,6 +40,14 @@ nav:
         - 'Special Phrases': 'customize/Special-Phrases.md'
         - 'External data: US housenumbers from TIGER': 'customize/Tiger.md'
         - 'External data: Postcodes': 'customize/Postcodes.md'
+        - 'Conversion to SQLite': 'customize/SQLite.md'
+    - 'Library Guide':
+        - 'Getting Started': 'library/Getting-Started.md'
+        - 'Nominatim API class': 'library/NominatimAPI.md'
+        - 'Configuration': 'library/Configuration.md'
+        - 'Input Parameter Types': 'library/Input-Parameter-Types.md'
+        - 'Result Handling': 'library/Result-Handling.md'
+        - 'Low-level DB Access': 'library/Low-Level-DB-Access.md'
     - 'Developers Guide':
         - 'Architecture Overview' : 'develop/overview.md'
         - 'Database Layout' : 'develop/Database-Layout.md'
@@ -45,12 +58,14 @@ nav:
         - 'Testing' : 'develop/Testing.md'
         - 'External Data Sources': 'develop/data-sources.md'
     - 'Appendix':
-        - 'Installation on Ubuntu 18' : 'appendix/Install-on-Ubuntu-18.md'
         - 'Installation on Ubuntu 20' : 'appendix/Install-on-Ubuntu-20.md'
         - 'Installation on Ubuntu 22' : 'appendix/Install-on-Ubuntu-22.md'
 markdown_extensions:
     - codehilite
     - admonition
+    - pymdownx.superfences
+    - pymdownx.tabbed:
+        alternate_style: true
     - def_list
     - toc:
         permalink: 
@@ -59,7 +74,8 @@ plugins:
     - search
     - mkdocstrings:
         handlers:
-          python-legacy:
-            rendering:
-              show_source: false
-              show_signature_annotations: false
+          python:
+            paths: ["${PROJECT_SOURCE_DIR}"]
+            options:
+              show_source: False
+              show_bases: False

lib-php/DB.php

@@ -38,23 +38,25 @@ class DB
 
         // https://secure.php.net/manual/en/ref.pdo-pgsql.connection.php
         try {
-            $conn = new \PDO($this->sDSN, null, null, $aConnOptions);
+            $this->connection = new \PDO($this->sDSN, null, null, $aConnOptions);
         } catch (\PDOException $e) {
             $sMsg = 'Failed to establish database connection:' . $e->getMessage();
             throw new \Nominatim\DatabaseError($sMsg, 500, null, $e->getMessage());
         }
 
-        $conn->exec("SET DateStyle TO 'sql,european'");
-        $conn->exec("SET client_encoding TO 'utf-8'");
+        $this->connection->exec("SET DateStyle TO 'sql,european'");
+        $this->connection->exec("SET client_encoding TO 'utf-8'");
         // Disable JIT and parallel workers. They interfere badly with search SQL.
-        $conn->exec("UPDATE pg_settings SET setting = -1 WHERE name = 'jit_above_cost'");
-        $conn->exec("UPDATE pg_settings SET setting = 0 WHERE name = 'max_parallel_workers_per_gather'");
+        $this->connection->exec('SET max_parallel_workers_per_gather TO 0');
+        if ($this->getPostgresVersion() >= 11) {
+            $this->connection->exec('SET jit_above_cost TO -1');
+        }
+        
         $iMaxExecution = ini_get('max_execution_time');
         if ($iMaxExecution > 0) {
-            $conn->setAttribute(\PDO::ATTR_TIMEOUT, $iMaxExecution); // seconds
+            $this->connection->setAttribute(\PDO::ATTR_TIMEOUT, $iMaxExecution); // seconds
         }
 
-        $this->connection = $conn;
         return true;
     }
 

lib-php/DebugHtml.php

@@ -135,7 +135,7 @@ class Debug
 
     public static function printSQL($sSQL)
     {
-        echo '<p><tt><font color="#aaa">'.htmlspecialchars($sSQL, ENT_QUOTES | ENT_SUBSTITUTE | ENT_HTML401).'</font></tt></p>'."\n";
+        echo '<p><tt><b>'.date('c').'</b> <font color="#aaa">'.htmlspecialchars($sSQL, ENT_QUOTES | ENT_SUBSTITUTE | ENT_HTML401).'</font></tt></p>'."\n";
     }
 
     private static function outputVar($mVar, $sPreNL)

lib-php/PlaceLookup.php

@@ -86,7 +86,7 @@ class PlaceLookup
             ($this->bIncludePolygonAsSVG ? 1 : 0);
         if ($iWantedTypes > CONST_PolygonOutput_MaximumTypes) {
             if (CONST_PolygonOutput_MaximumTypes) {
-                userError('Select only '.CONST_PolygonOutput_MaximumTypes.' polgyon output option');
+                userError('Select only '.CONST_PolygonOutput_MaximumTypes.' polygon output option');
             } else {
                 userError('Polygon output is disabled');
             }

lib-php/ReverseGeocode.php

@@ -40,10 +40,10 @@ class ReverseGeocode
                       9 => 12,
                       10 => 17, // City
                       11 => 17,
-                      12 => 18, // Town / Village
-                      13 => 18,
-                      14 => 22, // Suburb
-                      15 => 22,
+                      12 => 18, // Town
+                      13 => 19, // Village
+                      14 => 22, // Neighbourhood
+                      15 => 25, // Locality
                       16 => 26, // major street
                       17 => 27, // minor street
                       18 => 30, // or >, Building
@@ -85,6 +85,11 @@ class ReverseGeocode
 
     protected function lookupLargeArea($sPointSQL, $iMaxRank)
     {
+        $sCountryCode = $this->getCountryCode($sPointSQL);
+        if (CONST_Search_WithinCountries and $sCountryCode == null) {
+            return  null;
+        }
+
         if ($iMaxRank > 4) {
             $aPlace = $this->lookupPolygon($sPointSQL, $iMaxRank);
             if ($aPlace) {
@@ -94,12 +99,12 @@ class ReverseGeocode
 
         // If no polygon which contains the searchpoint is found,
         // searches in the country_osm_grid table for a polygon.
-        return  $this->lookupInCountry($sPointSQL, $iMaxRank);
+        return  $this->lookupInCountry($sPointSQL, $iMaxRank, $sCountryCode);
     }
 
-    protected function lookupInCountry($sPointSQL, $iMaxRank)
+    protected function getCountryCode($sPointSQL)
     {
-        Debug::newFunction('lookupInCountry');
+        Debug::newFunction('getCountryCode');
         // searches for polygon in table country_osm_grid which contains the searchpoint
         // and searches for the nearest place node to the searchpoint in this polygon
         $sSQL = 'SELECT country_code FROM country_osm_grid';
@@ -111,8 +116,12 @@ class ReverseGeocode
             null,
             'Could not determine country polygon containing the point.'
         );
-        Debug::printVar('Country code', $sCountryCode);
+        return $sCountryCode;
+    }
 
+    protected function lookupInCountry($sPointSQL, $iMaxRank, $sCountryCode)
+    {
+        Debug::newFunction('lookupInCountry');
         if ($sCountryCode) {
             if ($iMaxRank > 4) {
                 // look for place nodes with the given country code
@@ -122,12 +131,13 @@ class ReverseGeocode
                 $sSQL .= ' FROM placex';
                 $sSQL .= ' WHERE osm_type = \'N\'';
                 $sSQL .= ' AND country_code = \''.$sCountryCode.'\'';
-                $sSQL .= ' AND rank_search < 26 '; // needed to select right index
+                $sSQL .= ' AND rank_address between 4 and 25'; // needed to select right index
                 $sSQL .= ' AND rank_search between 5 and ' .min(25, $iMaxRank);
-                $sSQL .= ' AND class = \'place\' AND type != \'postcode\'';
+                $sSQL .= ' AND type != \'postcode\'';
                 $sSQL .= ' AND name IS NOT NULL ';
                 $sSQL .= ' and indexed_status = 0 and linked_place_id is null';
-                $sSQL .= ' AND ST_DWithin('.$sPointSQL.', geometry, 1.8)) p ';
+                $sSQL .= ' AND ST_Buffer(geometry, reverse_place_diameter(rank_search)) && '.$sPointSQL;
+                $sSQL .= ') as a ';
                 $sSQL .= 'WHERE distance <= reverse_place_diameter(rank_search)';
                 $sSQL .= ' ORDER BY rank_search DESC, distance ASC';
                 $sSQL .= ' LIMIT 1';
@@ -216,23 +226,18 @@ class ReverseGeocode
                 $sSQL .= ' ST_distance('.$sPointSQL.', geometry) as distance';
                 $sSQL .= ' FROM placex';
                 $sSQL .= ' WHERE osm_type = \'N\'';
-                // using rank_search because of a better differentiation
-                // for place nodes at rank_address 16
                 $sSQL .= ' AND rank_search > '.$iRankSearch;
                 $sSQL .= ' AND rank_search <= '.$iMaxRank;
-                $sSQL .= ' AND rank_search < 26 '; // needed to select right index
-                $sSQL .= ' AND rank_address > 0';
-                $sSQL .= ' AND class = \'place\'';
+                $sSQL .= ' AND rank_address between 4 and 25';  // needed to select right index
                 $sSQL .= ' AND type != \'postcode\'';
                 $sSQL .= ' AND name IS NOT NULL ';
                 $sSQL .= ' AND indexed_status = 0 AND linked_place_id is null';
-                $sSQL .= ' AND ST_DWithin('.$sPointSQL.', geometry, reverse_place_diameter('.$iRankSearch.'::smallint))';
-                $sSQL .= ' ORDER BY distance ASC,';
-                $sSQL .= ' rank_address DESC';
-                $sSQL .= ' limit 500) as a';
-                $sSQL .= ' WHERE ST_CONTAINS((SELECT geometry FROM placex WHERE place_id = '.$iPlaceID.'), geometry )';
+                $sSQL .= ' AND ST_Buffer(geometry, reverse_place_diameter(rank_search)) && '.$sPointSQL;
+                $sSQL .= ' ORDER BY rank_search DESC, distance ASC';
+                $sSQL .= ' limit 100) as a';
+                $sSQL .= ' WHERE ST_Contains((SELECT geometry FROM placex WHERE place_id = '.$iPlaceID.'), geometry )';
                 $sSQL .= ' AND distance <= reverse_place_diameter(rank_search)';
-                $sSQL .= ' ORDER BY distance ASC, rank_search DESC';
+                $sSQL .= ' ORDER BY rank_search DESC, distance ASC';
                 $sSQL .= ' LIMIT 1';
                 Debug::printSQL($sSQL);
 

lib-php/admin/export.php

@@ -1,190 +0,0 @@
-<?php
-/**
- * SPDX-License-Identifier: GPL-2.0-only
- *
- * This file is part of Nominatim. (https://nominatim.org)
- *
- * Copyright (C) 2022 by the Nominatim developer community.
- * For a full list of authors see the git log.
- */
-    @define('CONST_LibDir', dirname(dirname(__FILE__)));
-    // Script to extract structured city and street data
-    // from a running nominatim instance as CSV data
-
-
-    require_once(CONST_LibDir.'/init-cmd.php');
-    require_once(CONST_LibDir.'/ParameterParser.php');
-    ini_set('memory_limit', '800M');
-
-    $aCMDOptions = array(
-                    'Export addresses as CSV file from a Nominatim database',
-                    array('help', 'h', 0, 1, 0, 0, false, 'Show Help'),
-                    array('quiet', 'q', 0, 1, 0, 0, 'bool', 'Quiet output'),
-                    array('verbose', 'v', 0, 1, 0, 0, 'bool', 'Verbose output'),
-
-                    array('output-type', '', 0, 1, 1, 1, 'str', 'Type of places to output (see below)'),
-                    array('output-format', '', 0, 1, 1, 1, 'str', 'Column mapping (see below)'),
-                    array('output-all-postcodes', '', 0, 1, 0, 0, 'bool', 'List all postcodes for address instead of just the most likely one'),
-                    array('language', '', 0, 1, 1, 1, 'str', 'Preferred language for output (local name, if omitted)'),
-                    array('restrict-to-country', '', 0, 1, 1, 1, 'str', 'Export only objects within country (country code)'),
-                    array('restrict-to-osm-node', '', 0, 1, 1, 1, 'int', 'Export only objects that are children of this OSM node'),
-                    array('restrict-to-osm-way', '', 0, 1, 1, 1, 'int', 'Export only objects that are children of this OSM way'),
-                    array('restrict-to-osm-relation', '', 0, 1, 1, 1, 'int', 'Export only objects that are children of this OSM relation'),
-                    array('project-dir', '', 0, 1, 1, 1, 'realpath', 'Base directory of the Nominatim installation (default: .)'),
-                    "\nAddress ranks: continent, country, state, county, city, suburb, street, path",
-                    'Additional output types: postcode, placeid (placeid for each object)',
-                    "\noutput-format must be a semicolon-separated list of address ranks. Multiple ranks",
-                    'can be merged into one column by simply using a comma-separated list.',
-                    "\nDefault output-type: street",
-        'Default output format: street;suburb;city;county;state;country'
-                   );
-    getCmdOpt($_SERVER['argv'], $aCMDOptions, $aCMDResult, true, true);
-
-    loadSettings($aCMDResult['project-dir'] ?? getcwd());
-
-    $aRankmap = array(
-                 'continent' => 1,
-                 'country' => 4,
-                 'state' => 8,
-                 'county' => 12,
-                 'city' => 16,
-                 'suburb' => 20,
-                 'street' => 26,
-                 'path' => 27
-                );
-
-    $oDB = new Nominatim\DB();
-    $oDB->connect();
-
-    if (isset($aCMDResult['output-type'])) {
-        if (!isset($aRankmap[$aCMDResult['output-type']])) {
-            fail('unknown output-type: '.$aCMDResult['output-type']);
-        }
-        $iOutputRank = $aRankmap[$aCMDResult['output-type']];
-    } else {
-        $iOutputRank = $aRankmap['street'];
-    }
-
-
-    // Preferred language
-    $oParams = new Nominatim\ParameterParser();
-    if (!isset($aCMDResult['language'])) {
-        $aCMDResult['language'] = 'xx';
-    }
-    $aLangPrefOrder = $oParams->getPreferredLanguages($aCMDResult['language']);
-    $sLanguagePrefArraySQL = $oDB->getArraySQL($oDB->getDBQuotedList($aLangPrefOrder));
-
-    // output formatting: build up a lookup table that maps address ranks to columns
-    $aColumnMapping = array();
-    $iNumCol = 0;
-    if (!isset($aCMDResult['output-format'])) {
-        $aCMDResult['output-format'] = 'street;suburb;city;county;state;country';
-    }
-    foreach (preg_split('/\s*;\s*/', $aCMDResult['output-format']) as $sColumn) {
-        $bHasData = false;
-        foreach (preg_split('/\s*,\s*/', $sColumn) as $sRank) {
-            if ($sRank == 'postcode' || $sRank == 'placeid') {
-                $aColumnMapping[$sRank] = $iNumCol;
-                $bHasData = true;
-            } elseif (isset($aRankmap[$sRank])) {
-                $iRank = $aRankmap[$sRank];
-                if ($iRank <= $iOutputRank) {
-                    $aColumnMapping[(string)$iRank] = $iNumCol;
-                    $bHasData = true;
-                }
-            }
-        }
-        if ($bHasData) {
-            $iNumCol++;
-        }
-    }
-
-    // build the query for objects
-    $sPlacexSQL = 'select min(place_id) as place_id, ';
-    $sPlacexSQL .= 'array_agg(place_id) as place_ids, ';
-    $sPlacexSQL .= 'country_code as cc, ';
-    $sPlacexSQL .= 'postcode, ';
-    // get the address places excluding postcodes
-    $sPlacexSQL .= 'array(select address_place_id from place_addressline a';
-    $sPlacexSQL .= ' where a.place_id = placex.place_id and isaddress';
-    $sPlacexSQL .= '  and address_place_id != placex.place_id';
-    $sPlacexSQL .= '  and not cached_rank_address in (5,11)';
-    $sPlacexSQL .= '  and cached_rank_address > 2 order by cached_rank_address)';
-    $sPlacexSQL .= ' as address';
-    $sPlacexSQL .= ' from placex where name is not null and linked_place_id is null';
-
-    $sPlacexSQL .= ' and rank_address = '.$iOutputRank;
-
-    if (isset($aCMDResult['restrict-to-country'])) {
-        $sPlacexSQL .= ' and country_code = '.$oDB->getDBQuoted($aCMDResult['restrict-to-country']);
-    }
-
-    // restriction to parent place id
-    $sParentId = false;
-    $sOsmType = false;
-
-    if (isset($aCMDResult['restrict-to-osm-node'])) {
-        $sOsmType = 'N';
-        $sOsmId = $aCMDResult['restrict-to-osm-node'];
-    }
-    if (isset($aCMDResult['restrict-to-osm-way'])) {
-        $sOsmType = 'W';
-        $sOsmId = $aCMDResult['restrict-to-osm-way'];
-    }
-    if (isset($aCMDResult['restrict-to-osm-relation'])) {
-        $sOsmType = 'R';
-        $sOsmId = $aCMDResult['restrict-to-osm-relation'];
-    }
-    if ($sOsmType) {
-        $sSQL = 'select place_id from placex where osm_type = :osm_type and osm_id = :osm_id';
-        $sParentId = $oDB->getOne($sSQL, array('osm_type' => $sOsmType, 'osm_id' => $sOsmId));
-        if (!$sParentId) {
-            fail('Could not find place '.$sOsmType.' '.$sOsmId);
-        }
-    }
-    if ($sParentId) {
-        $sPlacexSQL .= ' and place_id in (select place_id from place_addressline where address_place_id = '.$sParentId.' and isaddress)';
-    }
-
-    $sPlacexSQL .= " group by name->'name', address, postcode, country_code, placex.place_id";
-
-    // Iterate over placeids
-    // to get further hierarchical information
-    //var_dump($sPlacexSQL);
-    $oResults = $oDB->getQueryStatement($sPlacexSQL);
-    $fOutstream = fopen('php://output', 'w');
-    while ($aRow = $oResults->fetch()) {
-        $iPlaceID = $aRow['place_id'];
-        $sSQL = "select rank_address,get_name_by_language(name,$sLanguagePrefArraySQL) as localname from get_addressdata(:place_id, -1)";
-        $sSQL .= ' WHERE isaddress';
-        $sSQL .= ' order by rank_address desc,isaddress desc';
-        $aAddressLines = $oDB->getAll($sSQL, array('place_id' => $iPlaceID));
-
-        $aOutput = array_fill(0, $iNumCol, '');
-        // output address parts
-        foreach ($aAddressLines as $aAddress) {
-            if (isset($aColumnMapping[$aAddress['rank_address']])) {
-                $aOutput[$aColumnMapping[$aAddress['rank_address']]] = $aAddress['localname'];
-            }
-        }
-        // output postcode
-        if (isset($aColumnMapping['postcode'])) {
-            if ($aCMDResult['output-all-postcodes']) {
-                $sSQL = 'select array_agg(px.postcode) from placex px join place_addressline pa ';
-                $sSQL .= 'on px.place_id = pa.address_place_id ';
-                $sSQL .= 'where pa.cached_rank_address in (5,11) ';
-                $sSQL .= 'and pa.place_id in (select place_id from place_addressline where address_place_id in (:first_place_id)) ';
-                $sSQL .= 'group by postcode order by count(*) desc limit 1';
-                $sRes = $oDB->getOne($sSQL, array('first_place_id' => substr($aRow['place_ids'], 1, -1)));
-
-                $aOutput[$aColumnMapping['postcode']] = substr($sRes, 1, -1);
-            } else {
-                $aOutput[$aColumnMapping['postcode']] = $aRow['postcode'];
-            }
-        }
-        if (isset($aColumnMapping['placeid'])) {
-            $aOutput[$aColumnMapping['placeid']] = substr($aRow['place_ids'], 1, -1);
-        }
-        fputcsv($fOutstream, $aOutput);
-    }
-    fclose($fOutstream);

lib-php/admin/warm.php

@@ -1,114 +0,0 @@
-<?php
-/**
- * SPDX-License-Identifier: GPL-2.0-only
- *
- * This file is part of Nominatim. (https://nominatim.org)
- *
- * Copyright (C) 2022 by the Nominatim developer community.
- * For a full list of authors see the git log.
- */
-@define('CONST_LibDir', dirname(dirname(__FILE__)));
-
-require_once(CONST_LibDir.'/init-cmd.php');
-require_once(CONST_LibDir.'/log.php');
-require_once(CONST_LibDir.'/PlaceLookup.php');
-require_once(CONST_LibDir.'/ReverseGeocode.php');
-
-ini_set('memory_limit', '800M');
-
-$aCMDOptions = array(
-                'Tools to warm nominatim db',
-                array('help', 'h', 0, 1, 0, 0, false, 'Show Help'),
-                array('quiet', 'q', 0, 1, 0, 0, 'bool', 'Quiet output'),
-                array('verbose', 'v', 0, 1, 0, 0, 'bool', 'Verbose output'),
-                array('reverse-only', '', 0, 1, 0, 0, 'bool', 'Warm reverse only'),
-                array('search-only', '', 0, 1, 0, 0, 'bool', 'Warm search only'),
-                array('project-dir', '', 0, 1, 1, 1, 'realpath', 'Base directory of the Nominatim installation (default: .)'),
-               );
-getCmdOpt($_SERVER['argv'], $aCMDOptions, $aResult, true, true);
-
-loadSettings($aCMDResult['project-dir'] ?? getcwd());
-
-@define('CONST_Database_DSN', getSetting('DATABASE_DSN'));
-@define('CONST_Default_Language', getSetting('DEFAULT_LANGUAGE', false));
-@define('CONST_Log_DB', getSettingBool('LOG_DB'));
-@define('CONST_Log_File', getSetting('LOG_FILE', false));
-@define('CONST_NoAccessControl', getSettingBool('CORS_NOACCESSCONTROL'));
-@define('CONST_Places_Max_ID_count', getSetting('LOOKUP_MAX_COUNT'));
-@define('CONST_PolygonOutput_MaximumTypes', getSetting('POLYGON_OUTPUT_MAX_TYPES'));
-@define('CONST_Search_BatchMode', getSettingBool('SEARCH_BATCH_MODE'));
-@define('CONST_Search_NameOnlySearchFrequencyThreshold', getSetting('SEARCH_NAME_ONLY_THRESHOLD'));
-@define('CONST_Use_US_Tiger_Data', getSettingBool('USE_US_TIGER_DATA'));
-@define('CONST_MapIcon_URL', getSetting('MAPICON_URL', false));
-@define('CONST_TokenizerDir', CONST_InstallDir.'/tokenizer');
-
-require_once(CONST_LibDir.'/Geocode.php');
-
-$oDB = new Nominatim\DB();
-$oDB->connect();
-
-$bVerbose = $aResult['verbose'];
-
-function print_results($aResults, $bVerbose)
-{
-    if ($bVerbose) {
-        if ($aResults && count($aResults)) {
-            echo $aResults[0]['langaddress']."\n";
-        } else {
-            echo "<not found>\n";
-        }
-    } else {
-        echo '.';
-    }
-}
-
-if (!$aResult['search-only']) {
-    $oReverseGeocode = new Nominatim\ReverseGeocode($oDB);
-    $oReverseGeocode->setZoom(20);
-    $oPlaceLookup = new Nominatim\PlaceLookup($oDB);
-    $oPlaceLookup->setIncludeAddressDetails(true);
-    $oPlaceLookup->setLanguagePreference(array('en'));
-
-    echo 'Warm reverse: ';
-    if ($bVerbose) {
-        echo "\n";
-    }
-    for ($i = 0; $i < 1000; $i++) {
-        $fLat = rand(-9000, 9000) / 100;
-        $fLon = rand(-18000, 18000) / 100;
-        if ($bVerbose) {
-            echo "$fLat, $fLon = ";
-        }
-
-        $oLookup = $oReverseGeocode->lookup($fLat, $fLon);
-        $aSearchResults = $oLookup ? $oPlaceLookup->lookup(array($oLookup->iId => $oLookup)) : null;
-        print_results($aSearchResults, $bVerbose);
-    }
-    echo "\n";
-}
-
-if (!$aResult['reverse-only']) {
-    $oGeocode = new Nominatim\Geocode($oDB);
-
-    echo 'Warm search: ';
-    if ($bVerbose) {
-        echo "\n";
-    }
-
-    $oTokenizer = new \Nominatim\Tokenizer($oDB);
-
-    $aWords = $oTokenizer->mostFrequentWords(1000);
-
-    $sSQL = 'SELECT word FROM word WHERE word is not null ORDER BY search_name_count DESC LIMIT 1000';
-    foreach ($aWords as $sWord) {
-        if ($bVerbose) {
-            echo "$sWord = ";
-        }
-
-        $oGeocode->setLanguagePreference(array('en'));
-        $oGeocode->setQuery($sWord);
-        $aSearchResults = $oGeocode->lookup();
-        print_results($aSearchResults, $bVerbose);
-    }
-    echo "\n";
-}

lib-php/website/details.php

@@ -23,7 +23,7 @@ $aLangPrefOrder = $oParams->getPreferredLanguages();
 
 $sPlaceId = $oParams->getString('place_id');
 $sOsmType = $oParams->getSet('osmtype', array('N', 'W', 'R'));
-$iOsmId = $oParams->getInt('osmid', -1);
+$iOsmId = $oParams->getInt('osmid', 0);
 $sClass = $oParams->getString('class');
 
 $bIncludeKeywords = $oParams->getBool('keywords', false);
@@ -38,7 +38,7 @@ $oDB->connect();
 
 $sLanguagePrefArraySQL = $oDB->getArraySQL($oDB->getDBQuotedList($aLangPrefOrder));
 
-if ($sOsmType && $iOsmId > 0) {
+if ($sOsmType && $iOsmId !== 0) {
     $sSQL = 'SELECT place_id FROM placex WHERE osm_type = :type AND osm_id = :id';
     $aSQLParams = array(':type' => $sOsmType, ':id' => $iOsmId);
     // osm_type and osm_id are not unique enough

lib-sql/functions/address_lookup.sql

@@ -187,6 +187,7 @@ BEGIN
 
   -- --- Return the record for the base entry.
 
+  current_rank_address := 1000;
   FOR location IN
     SELECT placex.place_id, osm_type, osm_id, name,
            coalesce(extratags->'linked_place', extratags->'place') as place_type,
@@ -261,7 +262,7 @@ BEGIN
       -- If the place had a postcode assigned, take this one only
       -- into consideration when it is an area and the place does not have
       -- a postcode itself.
-      IF location.fromarea AND location.isaddress
+      IF location.fromarea AND location_isaddress
          AND (place.address is null or not place.address ? 'postcode')
       THEN
         place.postcode := null; -- remove the less exact postcode

lib-sql/functions/importance.sql

@@ -62,10 +62,6 @@ BEGIN
   WHILE langs[i] IS NOT NULL LOOP
     wiki_article := extratags->(case when langs[i] in ('english','country') THEN 'wikipedia' ELSE 'wikipedia:'||langs[i] END);
     IF wiki_article is not null THEN
-      wiki_article := regexp_replace(wiki_article,E'^(.*?)([a-z]{2,3}).wikipedia.org/wiki/',E'\\2:');
-      wiki_article := regexp_replace(wiki_article,E'^(.*?)([a-z]{2,3}).wikipedia.org/w/index.php\\?title=',E'\\2:');
-      wiki_article := regexp_replace(wiki_article,E'^(.*?)/([a-z]{2,3})/wiki/',E'\\2:');
-      --wiki_article := regexp_replace(wiki_article,E'^(.*?)([a-z]{2,3})[=:]',E'\\2:');
       wiki_article := replace(wiki_article,' ','_');
       IF strpos(wiki_article, ':') IN (3,4) THEN
         wiki_article_language := lower(trim(split_part(wiki_article, ':', 1)));
@@ -134,7 +130,7 @@ BEGIN
 
   -- Still nothing? Fall back to a default.
   IF result.importance is null THEN
-    result.importance := 0.75001 - (rank_search::float / 40);
+    result.importance := 0.40001 - (rank_search::float / 75);
   END IF;
 
 {% if 'secondary_importance' in db.tables %}

lib-sql/functions/interpolation.sql

@@ -164,7 +164,7 @@ DECLARE
   newend INTEGER;
   moddiff SMALLINT;
   linegeo GEOMETRY;
-  splitline GEOMETRY;
+  splitpoint FLOAT;
   sectiongeo GEOMETRY;
   postcode TEXT;
   stepmod SMALLINT;
@@ -219,19 +219,32 @@ BEGIN
           -- formatted postcode and therefore 'postcode' contains a derived
           -- variant.
           CASE WHEN address ? 'postcode' THEN placex.postcode ELSE NULL::text END as postcode,
-          substring(address->'housenumber','[0-9]+')::integer as hnr
+          (address->'housenumber')::integer as hnr
         FROM placex, generate_series(1, array_upper(waynodes, 1)) nodeidpos
         WHERE osm_type = 'N' and osm_id = waynodes[nodeidpos]::BIGINT
               and address is not NULL and address ? 'housenumber'
+              and address->'housenumber' ~ '^[0-9]{1,6}$'
+              and ST_Distance(NEW.linegeo, geometry) < 0.0005
         ORDER BY nodeidpos
     LOOP
       {% if debug %}RAISE WARNING 'processing point % (%)', nextnode.hnr, ST_AsText(nextnode.geometry);{% endif %}
       IF linegeo is null THEN
         linegeo := NEW.linegeo;
       ELSE
-        splitline := ST_Split(ST_Snap(linegeo, nextnode.geometry, 0.0005), nextnode.geometry);
-        sectiongeo := ST_GeometryN(splitline, 1);
-        linegeo := ST_GeometryN(splitline, 2);
+        splitpoint := ST_LineLocatePoint(linegeo, nextnode.geometry);
+        IF splitpoint = 0 THEN
+          -- Corner case where the splitpoint falls on the first point
+          -- and thus would not return a geometry. Skip that section.
+          sectiongeo := NULL;
+        ELSEIF splitpoint = 1 THEN
+          -- Point is at the end of the line.
+          sectiongeo := linegeo;
+          linegeo := NULL;
+        ELSE
+          -- Split the line.
+          sectiongeo := ST_LineSubstring(linegeo, 0, splitpoint);
+          linegeo := ST_LineSubstring(linegeo, splitpoint, 1);
+        END IF;
       END IF;
 
       IF prevnode.hnr is not null
@@ -239,6 +252,9 @@ BEGIN
          -- regularly mapped housenumbers.
          -- (Conveniently also fails if one of the house numbers is not a number.)
          and abs(prevnode.hnr - nextnode.hnr) > NEW.step
+         -- If the interpolation geometry is broken or two nodes are at the
+         -- same place, then splitting might produce a point. Ignore that.
+         and ST_GeometryType(sectiongeo) = 'ST_LineString'
       THEN
         IF prevnode.hnr < nextnode.hnr THEN
           startnumber := prevnode.hnr;
@@ -300,12 +316,12 @@ BEGIN
                   NEW.address, postcode,
                   NEW.country_code, NEW.geometry_sector, 0);
         END IF;
+      END IF;
 
-        -- early break if we are out of line string,
-        -- might happen when a line string loops back on itself
-        IF ST_GeometryType(linegeo) != 'ST_LineString' THEN
-            RETURN NEW;
-        END IF;
+      -- early break if we are out of line string,
+      -- might happen when a line string loops back on itself
+      IF linegeo is null or ST_GeometryType(linegeo) != 'ST_LineString' THEN
+          RETURN NEW;
       END IF;
 
       prevnode := nextnode;

lib-sql/functions/place_triggers.sql

@@ -37,7 +37,7 @@ BEGIN
   -- Remove the place from the list of places to be deleted
   DELETE FROM place_to_be_deleted pdel
     WHERE pdel.osm_type = NEW.osm_type and pdel.osm_id = NEW.osm_id
-          and pdel.class = NEW.class;
+          and pdel.class = NEW.class and pdel.type = NEW.type;
 
   -- Have we already done this place?
   SELECT * INTO existing
@@ -296,7 +296,9 @@ BEGIN
           extratags = NEW.extratags,
           admin_level = NEW.admin_level,
           indexed_status = 2,
-          geometry = NEW.geometry
+          geometry = CASE WHEN existingplacex.rank_address = 0
+                          THEN simplify_large_polygons(NEW.geometry)
+                          ELSE NEW.geometry END
       WHERE place_id = existingplacex.place_id;
 
     -- Invalidate linked places: they potentially get a new name and addresses.
@@ -363,57 +365,3 @@ BEGIN
   RETURN NULL;
 END;
 $$ LANGUAGE plpgsql;
-
-CREATE OR REPLACE FUNCTION flush_deleted_places()
-  RETURNS INTEGER
-  AS $$
-BEGIN
-  -- deleting large polygons can have a massive effect on the system - require manual intervention to let them through
-  INSERT INTO import_polygon_delete (osm_type, osm_id, class, type)
-    SELECT osm_type, osm_id, class, type FROM place_to_be_deleted WHERE deferred;
-
-  -- delete from place table
-  ALTER TABLE place DISABLE TRIGGER place_before_delete;
-  DELETE FROM place USING place_to_be_deleted
-    WHERE place.osm_type = place_to_be_deleted.osm_type
-          and place.osm_id = place_to_be_deleted.osm_id
-          and place.class = place_to_be_deleted.class
-          and place.type = place_to_be_deleted.type
-          and not deferred;
-  ALTER TABLE place ENABLE TRIGGER place_before_delete;
-
-  -- Mark for delete in the placex table
-  UPDATE placex SET indexed_status = 100 FROM place_to_be_deleted
-    WHERE placex.osm_type = 'N' and place_to_be_deleted.osm_type = 'N'
-          and placex.osm_id = place_to_be_deleted.osm_id
-          and placex.class = place_to_be_deleted.class
-          and placex.type = place_to_be_deleted.type
-          and not deferred;
-  UPDATE placex SET indexed_status = 100 FROM place_to_be_deleted
-    WHERE placex.osm_type = 'W' and place_to_be_deleted.osm_type = 'W'
-          and placex.osm_id = place_to_be_deleted.osm_id
-          and placex.class = place_to_be_deleted.class
-          and placex.type = place_to_be_deleted.type
-          and not deferred;
-  UPDATE placex SET indexed_status = 100 FROM place_to_be_deleted
-    WHERE placex.osm_type = 'R' and place_to_be_deleted.osm_type = 'R'
-          and placex.osm_id = place_to_be_deleted.osm_id
-          and placex.class = place_to_be_deleted.class
-          and placex.type = place_to_be_deleted.type
-          and not deferred;
-
-   -- Mark for delete in interpolations
-   UPDATE location_property_osmline SET indexed_status = 100 FROM place_to_be_deleted
-    WHERE place_to_be_deleted.osm_type = 'W'
-          and place_to_be_deleted.class = 'place'
-          and place_to_be_deleted.type = 'houses'
-          and location_property_osmline.osm_id = place_to_be_deleted.osm_id
-          and not deferred;
-
-   -- Clear todo list.
-   TRUNCATE TABLE place_to_be_deleted;
-
-   RETURN NULL;
-END;
-$$ LANGUAGE plpgsql;
-

lib-sql/functions/placex_triggers.sql

@@ -2,7 +2,7 @@
 --
 -- This file is part of Nominatim. (https://nominatim.org)
 --
--- Copyright (C) 2022 by the Nominatim developer community.
+-- Copyright (C) 2024 by the Nominatim developer community.
 -- For a full list of authors see the git log.
 
 -- Trigger functions for the placex table.
@@ -88,12 +88,18 @@ BEGIN
       -- Add all names from the place nodes that deviate from the name
       -- in the relation with the prefix '_place_'. Deviation means that
       -- either the value is different or a given key is missing completely
-      SELECT hstore(array_agg('_place_' || key), array_agg(value)) INTO extra_names
-        FROM each(location.name - result.name);
-      {% if debug %}RAISE WARNING 'Extra names: %', extra_names;{% endif %}
+      IF result.name is null THEN
+        SELECT hstore(array_agg('_place_' || key), array_agg(value))
+          INTO result.name
+          FROM each(location.name);
+      ELSE
+        SELECT hstore(array_agg('_place_' || key), array_agg(value)) INTO extra_names
+          FROM each(location.name - result.name);
+        {% if debug %}RAISE WARNING 'Extra names: %', extra_names;{% endif %}
 
-      IF extra_names is not null THEN
-          result.name := result.name || extra_names;
+        IF extra_names is not null THEN
+            result.name := result.name || extra_names;
+        END IF;
       END IF;
 
       {% if debug %}RAISE WARNING 'Final names: %', result.name;{% endif %}
@@ -113,12 +119,14 @@ CREATE OR REPLACE FUNCTION find_associated_street(poi_osm_type CHAR(1),
   AS $$
 DECLARE
   location RECORD;
+  member JSONB;
   parent RECORD;
   result BIGINT;
   distance FLOAT;
   new_distance FLOAT;
   waygeom GEOMETRY;
 BEGIN
+{% if db.middle_db_format == '1' %}
   FOR location IN
     SELECT members FROM planet_osm_rels
     WHERE parts @> ARRAY[poi_osm_id]
@@ -155,6 +163,40 @@ BEGIN
     END LOOP;
   END LOOP;
 
+{% else %}
+  FOR member IN
+    SELECT value FROM planet_osm_rels r, LATERAL jsonb_array_elements(members)
+    WHERE planet_osm_member_ids(members, poi_osm_type::char(1)) && ARRAY[poi_osm_id]
+          and tags->>'type' = 'associatedStreet'
+          and value->>'role' = 'street'
+  LOOP
+    FOR parent IN
+      SELECT place_id, geometry
+       FROM placex
+       WHERE osm_type = (member->>'type')::char(1)
+             and osm_id = (member->>'ref')::bigint
+             and name is not null
+             and rank_search between 26 and 27
+    LOOP
+      -- Find the closest 'street' member.
+      -- Avoid distance computation for the frequent case where there is
+      -- only one street member.
+      IF waygeom is null THEN
+        result := parent.place_id;
+        waygeom := parent.geometry;
+      ELSE
+        distance := coalesce(distance, ST_Distance(waygeom, bbox));
+        new_distance := ST_Distance(parent.geometry, bbox);
+        IF new_distance < distance THEN
+          distance := new_distance;
+          result := parent.place_id;
+          waygeom := parent.geometry;
+        END IF;
+      END IF;
+    END LOOP;
+  END LOOP;
+{% endif %}
+
   RETURN result;
 END;
 $$
@@ -251,7 +293,11 @@ CREATE OR REPLACE FUNCTION find_linked_place(bnd placex)
   RETURNS placex
   AS $$
 DECLARE
+{% if db.middle_db_format == '1' %}
   relation_members TEXT[];
+{% else %}
+  relation_members JSONB;
+{% endif %}
   rel_member RECORD;
   linked_placex placex%ROWTYPE;
   bnd_name TEXT;
@@ -672,6 +718,12 @@ BEGIN
       NEW.country_code := NULL;
     END IF;
 
+    -- Simplify polygons with a very large memory footprint when they
+    -- do not take part in address computation.
+    IF NEW.rank_address = 0 THEN
+      NEW.geometry := simplify_large_polygons(NEW.geometry);
+    END IF;
+
   END IF;
 
   {% if debug %}RAISE WARNING 'placex_insert:END: % % % %',NEW.osm_type,NEW.osm_id,NEW.class,NEW.type;{% endif %}
@@ -679,10 +731,12 @@ BEGIN
 {% if not disable_diff_updates %}
   -- The following is not needed until doing diff updates, and slows the main index process down
 
-  IF NEW.rank_address > 0 THEN
+  IF NEW.rank_address between 2 and 27 THEN
     IF (ST_GeometryType(NEW.geometry) in ('ST_Polygon','ST_MultiPolygon') AND ST_IsValid(NEW.geometry)) THEN
       -- Performance: We just can't handle re-indexing for country level changes
-      IF st_area(NEW.geometry) < 1 THEN
+      IF (NEW.rank_address < 26 and st_area(NEW.geometry) < 1)
+         OR (NEW.rank_address >= 26 and st_area(NEW.geometry) < 0.01)
+      THEN
         -- mark items within the geometry for re-indexing
   --    RAISE WARNING 'placex poly insert: % % % %',NEW.osm_type,NEW.osm_id,NEW.class,NEW.type;
 
@@ -697,9 +751,11 @@ BEGIN
                     or name is not null
                     or (NEW.rank_address >= 16 and address ? 'place'));
       END IF;
-    ELSE
+    ELSEIF ST_GeometryType(NEW.geometry) not in ('ST_LineString', 'ST_MultiLineString')
+           OR ST_Length(NEW.geometry) < 0.5
+    THEN
       -- mark nearby items for re-indexing, where 'nearby' depends on the features rank_search and is a complete guess :(
-      diameter := update_place_diameter(NEW.rank_search);
+      diameter := update_place_diameter(NEW.rank_address);
       IF diameter > 0 THEN
   --      RAISE WARNING 'placex point insert: % % % % %',NEW.osm_type,NEW.osm_id,NEW.class,NEW.type,diameter;
         IF NEW.rank_search >= 26 THEN
@@ -743,7 +799,11 @@ CREATE OR REPLACE FUNCTION placex_update()
 DECLARE
   i INTEGER;
   location RECORD;
+{% if db.middle_db_format == '1' %}
   relation_members TEXT[];
+{% else %}
+  relation_member JSONB;
+{% endif %}
 
   geom GEOMETRY;
   parent_address_level SMALLINT;
@@ -788,6 +848,9 @@ BEGIN
   result := deleteLocationArea(NEW.partition, NEW.place_id, NEW.rank_search);
 
   NEW.extratags := NEW.extratags - 'linked_place'::TEXT;
+  IF NEW.extratags = ''::hstore THEN
+    NEW.extratags := NULL;
+  END IF;
 
   -- NEW.linked_place_id contains the precomputed linkee. Save this and restore
   -- the previous link status.
@@ -962,6 +1025,7 @@ BEGIN
 
   -- waterway ways are linked when they are part of a relation and have the same class/type
   IF NEW.osm_type = 'R' and NEW.class = 'waterway' THEN
+{% if db.middle_db_format == '1' %}
       FOR relation_members IN select members from planet_osm_rels r where r.id = NEW.osm_id and r.parts != array[]::bigint[]
       LOOP
           FOR i IN 1..array_upper(relation_members, 1) BY 2 LOOP
@@ -980,6 +1044,29 @@ BEGIN
               END IF;
           END LOOP;
       END LOOP;
+{% else %}
+    FOR relation_member IN
+      SELECT value FROM planet_osm_rels r, LATERAL jsonb_array_elements(r.members)
+      WHERE r.id = NEW.osm_id
+    LOOP
+      IF relation_member->>'role' IN ('', 'main_stream', 'side_stream')
+         and relation_member->>'type' = 'W'
+      THEN
+        {% if debug %}RAISE WARNING 'waterway parent %, child %', NEW.osm_id, relation_member;{% endif %}
+        FOR linked_node_id IN
+          SELECT place_id FROM placex
+          WHERE osm_type = 'W' and osm_id = (relation_member->>'ref')::bigint
+                and class = NEW.class and type in ('river', 'stream', 'canal', 'drain', 'ditch')
+                and (relation_member->>'role' != 'side_stream' or NEW.name->'name' = name->'name')
+        LOOP
+          UPDATE placex SET linked_place_id = NEW.place_id WHERE place_id = linked_node_id;
+          {% if 'search_name' in db.tables %}
+            DELETE FROM search_name WHERE place_id = linked_node_id;
+          {% endif %}
+        END LOOP;
+      END IF;
+    END LOOP;
+{% endif %}
       {% if debug %}RAISE WARNING 'Waterway processed';{% endif %}
   END IF;
 
@@ -996,7 +1083,7 @@ BEGIN
 
     {% if debug %}RAISE WARNING 'finding street for % %', NEW.osm_type, NEW.osm_id;{% endif %}
     NEW.parent_place_id := null;
-    is_place_address := coalesce(not NEW.address ? 'street' and NEW.address ? 'place', FALSE);
+    is_place_address := not token_is_street_address(NEW.token_info);
 
     -- We have to find our parent road.
     NEW.parent_place_id := find_parent_for_poi(NEW.osm_type, NEW.osm_id,
@@ -1013,7 +1100,7 @@ BEGIN
       SELECT p.country_code, p.postcode, p.name FROM placex p
        WHERE p.place_id = NEW.parent_place_id INTO location;
 
-      IF is_place_address THEN
+      IF is_place_address and NEW.address ? 'place' THEN
         -- Check if the addr:place tag is part of the parent name
         SELECT count(*) INTO i
           FROM svals(location.name) AS pname WHERE pname = NEW.address->'place';
@@ -1182,6 +1269,8 @@ BEGIN
     END IF;
   ELSEIF NEW.rank_address > 25 THEN
     max_rank := 25;
+  ELSEIF NEW.class in ('place','boundary') and NEW.type in ('postcode','postal_code') THEN
+    max_rank := NEW.rank_search;
   ELSE
     max_rank := NEW.rank_address;
   END IF;
@@ -1235,7 +1324,9 @@ BEGIN
           OR ST_GeometryType(NEW.geometry) not in ('ST_LineString','ST_MultiLineString')
           OR ST_Length(NEW.geometry) < 0.02)
   THEN
-    NEW.postcode := get_nearest_postcode(NEW.country_code, NEW.geometry);
+    NEW.postcode := get_nearest_postcode(NEW.country_code,
+                                         CASE WHEN NEW.rank_address > 25
+                                              THEN NEW.centroid ELSE NEW.geometry END);
   END IF;
 
   {% if debug %}RAISE WARNING 'place update % % finished.', NEW.osm_type, NEW.osm_id;{% endif %}

lib-sql/functions/ranking.sql

@@ -284,3 +284,24 @@ BEGIN
 END;
 $$
 LANGUAGE plpgsql IMMUTABLE;
+
+
+CREATE OR REPLACE FUNCTION weigh_search(search_vector INT[],
+                                        rankings TEXT,
+                                        def_weight FLOAT)
+  RETURNS FLOAT
+  AS $$
+DECLARE
+  rank JSON;
+BEGIN
+  FOR rank IN
+    SELECT * FROM json_array_elements(rankings::JSON)
+  LOOP
+    IF true = ALL(SELECT x::int = ANY(search_vector) FROM json_array_elements_text(rank->1) as x) THEN
+      RETURN (rank->>0)::float;
+    END IF;
+  END LOOP;
+  RETURN def_weight;
+END;
+$$
+LANGUAGE plpgsql IMMUTABLE;

lib-sql/functions/utils.sql

@@ -73,6 +73,26 @@ END;
 $$
 LANGUAGE plpgsql IMMUTABLE;
 
+
+CREATE OR REPLACE FUNCTION get_rel_node_members(members JSONB, memberLabels TEXT[])
+  RETURNS SETOF BIGINT
+  AS $$
+DECLARE
+  member JSONB;
+BEGIN
+  FOR member IN SELECT * FROM jsonb_array_elements(members)
+  LOOP
+    IF member->>'type' = 'N' and member->>'role' = ANY(memberLabels) THEN
+        RETURN NEXT (member->>'ref')::bigint;
+    END IF;
+  END LOOP;
+
+  RETURN;
+END;
+$$
+LANGUAGE plpgsql IMMUTABLE;
+
+
 -- Copy 'name' to or from the default language.
 --
 -- \param country_code     Country code of the object being named.
@@ -273,8 +293,8 @@ BEGIN
   END IF;
 
   RETURN ST_Envelope(ST_Collect(
-                     ST_Project(geom, radius, 0.785398)::geometry,
-                     ST_Project(geom, radius, 3.9269908)::geometry));
+                     ST_Project(geom::geography, radius, 0.785398)::geometry,
+                     ST_Project(geom::geography, radius, 3.9269908)::geometry));
 END;
 $$
 LANGUAGE plpgsql IMMUTABLE;
@@ -416,6 +436,20 @@ END;
 $$
 LANGUAGE plpgsql IMMUTABLE;
 
+CREATE OR REPLACE FUNCTION simplify_large_polygons(geometry GEOMETRY)
+  RETURNS GEOMETRY
+  AS $$
+BEGIN
+  IF ST_GeometryType(geometry) in ('ST_Polygon','ST_MultiPolygon')
+     and ST_MemSize(geometry) > 3000000
+  THEN
+    geometry := ST_SimplifyPreserveTopology(geometry, 0.0001);
+  END IF;
+  RETURN geometry;
+END;
+$$
+LANGUAGE plpgsql IMMUTABLE;
+
 
 CREATE OR REPLACE FUNCTION place_force_delete(placeid BIGINT)
   RETURNS BOOLEAN
@@ -429,9 +463,10 @@ BEGIN
   SELECT osm_type, osm_id, class, type FROM placex WHERE place_id = placeid INTO osmtype, osmid, pclass, ptype;
   DELETE FROM import_polygon_delete where osm_type = osmtype and osm_id = osmid and class = pclass and type = ptype;
   DELETE FROM import_polygon_error where osm_type = osmtype and osm_id = osmid and class = pclass and type = ptype;
-  -- force delete from place/placex by making it a very small geometry
-  UPDATE place set geometry = ST_SetSRID(ST_Point(0,0), 4326) where osm_type = osmtype and osm_id = osmid and class = pclass and type = ptype;
-  DELETE FROM place where osm_type = osmtype and osm_id = osmid and class = pclass and type = ptype;
+  -- force delete by directly entering it into the to-be-deleted table
+  INSERT INTO place_to_be_deleted (osm_type, osm_id, class, type, deferred)
+         VALUES(osmtype, osmid, pclass, ptype, false);
+  PERFORM flush_deleted_places();
 
   RETURN TRUE;
 END;
@@ -486,3 +521,56 @@ BEGIN
 END;
 $$
 LANGUAGE plpgsql;
+
+CREATE OR REPLACE FUNCTION flush_deleted_places()
+  RETURNS INTEGER
+  AS $$
+BEGIN
+  -- deleting large polygons can have a massive effect on the system - require manual intervention to let them through
+  INSERT INTO import_polygon_delete (osm_type, osm_id, class, type)
+    SELECT osm_type, osm_id, class, type FROM place_to_be_deleted WHERE deferred;
+
+  -- delete from place table
+  ALTER TABLE place DISABLE TRIGGER place_before_delete;
+  DELETE FROM place USING place_to_be_deleted
+    WHERE place.osm_type = place_to_be_deleted.osm_type
+          and place.osm_id = place_to_be_deleted.osm_id
+          and place.class = place_to_be_deleted.class
+          and place.type = place_to_be_deleted.type
+          and not deferred;
+  ALTER TABLE place ENABLE TRIGGER place_before_delete;
+
+  -- Mark for delete in the placex table
+  UPDATE placex SET indexed_status = 100 FROM place_to_be_deleted
+    WHERE placex.osm_type = 'N' and place_to_be_deleted.osm_type = 'N'
+          and placex.osm_id = place_to_be_deleted.osm_id
+          and placex.class = place_to_be_deleted.class
+          and placex.type = place_to_be_deleted.type
+          and not deferred;
+  UPDATE placex SET indexed_status = 100 FROM place_to_be_deleted
+    WHERE placex.osm_type = 'W' and place_to_be_deleted.osm_type = 'W'
+          and placex.osm_id = place_to_be_deleted.osm_id
+          and placex.class = place_to_be_deleted.class
+          and placex.type = place_to_be_deleted.type
+          and not deferred;
+  UPDATE placex SET indexed_status = 100 FROM place_to_be_deleted
+    WHERE placex.osm_type = 'R' and place_to_be_deleted.osm_type = 'R'
+          and placex.osm_id = place_to_be_deleted.osm_id
+          and placex.class = place_to_be_deleted.class
+          and placex.type = place_to_be_deleted.type
+          and not deferred;
+
+   -- Mark for delete in interpolations
+   UPDATE location_property_osmline SET indexed_status = 100 FROM place_to_be_deleted
+    WHERE place_to_be_deleted.osm_type = 'W'
+          and place_to_be_deleted.class = 'place'
+          and place_to_be_deleted.type = 'houses'
+          and location_property_osmline.osm_id = place_to_be_deleted.osm_id
+          and not deferred;
+
+   -- Clear todo list.
+   TRUNCATE TABLE place_to_be_deleted;
+
+   RETURN NULL;
+END;
+$$ LANGUAGE plpgsql;

lib-sql/indices.sql

@@ -23,6 +23,10 @@ CREATE INDEX IF NOT EXISTS idx_placex_parent_place_id
 ---
 CREATE INDEX IF NOT EXISTS idx_placex_geometry ON placex
   USING GIST (geometry) {{db.tablespace.search_index}};
+-- Index is needed during import but can be dropped as soon as a full
+-- geometry index is in place. The partial index is almost as big as the full
+-- index.
+DROP INDEX IF EXISTS idx_placex_geometry_lower_rank_ways;
 ---
 CREATE INDEX IF NOT EXISTS idx_placex_geometry_reverse_lookupPolygon
   ON placex USING gist (geometry) {{db.tablespace.search_index}}
@@ -30,6 +34,13 @@ CREATE INDEX IF NOT EXISTS idx_placex_geometry_reverse_lookupPolygon
     AND rank_address between 4 and 25 AND type != 'postcode'
     AND name is not null AND indexed_status = 0 AND linked_place_id is null;
 ---
+-- used in reverse large area lookup
+CREATE INDEX IF NOT EXISTS idx_placex_geometry_reverse_lookupPlaceNode
+  ON placex USING gist (ST_Buffer(geometry, reverse_place_diameter(rank_search)))
+  {{db.tablespace.search_index}}
+  WHERE rank_address between 4 and 25 AND type != 'postcode'
+    AND name is not null AND linked_place_id is null AND osm_type = 'N';
+---
 CREATE INDEX IF NOT EXISTS idx_osmline_parent_place_id
   ON location_property_osmline USING BTREE (parent_place_id) {{db.tablespace.search_index}}
   WHERE parent_place_id is not null;

lib-sql/tables.sql

@@ -190,7 +190,6 @@ CREATE INDEX idx_placex_geometry_buildings ON placex
 
 -- Usage: - linking of similar named places to boundaries
 --        - linking of place nodes with same type to boundaries
---        - lookupPolygon()
 CREATE INDEX idx_placex_geometry_placenode ON placex
   USING {{postgres.spgist_geom}} (geometry) {{db.tablespace.address_index}}
   WHERE osm_type = 'N' and rank_search < 26
@@ -299,7 +298,15 @@ CREATE TABLE IF NOT EXISTS wikipedia_redirect (
 
 -- osm2pgsql does not create indexes on the middle tables for Nominatim
 -- Add one for lookup of associated street relations.
-CREATE INDEX planet_osm_rels_parts_associated_idx ON planet_osm_rels USING gin(parts) WHERE tags @> ARRAY['associatedStreet'];
+{% if db.middle_db_format == '1' %}
+CREATE INDEX planet_osm_rels_parts_associated_idx ON planet_osm_rels USING gin(parts)
+  {{db.tablespace.address_index}}
+  WHERE tags @> ARRAY['associatedStreet'];
+{% else %}
+CREATE INDEX planet_osm_rels_relation_members_idx ON planet_osm_rels USING gin(planet_osm_member_ids(members, 'R'::character(1)))
+  WITH (fastupdate=off)
+  {{db.tablespace.address_index}};
+{% endif %}
 
 -- Needed for lookups if a node is part of an interpolation.
 CREATE INDEX IF NOT EXISTS idx_place_interpolations

lib-sql/tokenizer/icu_tokenizer.sql

@@ -41,10 +41,17 @@ AS $$
 $$ LANGUAGE SQL IMMUTABLE STRICT;
 
 
+CREATE OR REPLACE FUNCTION token_is_street_address(info JSONB)
+  RETURNS BOOLEAN
+AS $$
+  SELECT info->>'street' is not null or info->>'place' is null;
+$$ LANGUAGE SQL IMMUTABLE;
+
+
 CREATE OR REPLACE FUNCTION token_has_addr_street(info JSONB)
   RETURNS BOOLEAN
 AS $$
-  SELECT info->>'street' is not null;
+  SELECT info->>'street' is not null and info->>'street' != '{}';
 $$ LANGUAGE SQL IMMUTABLE;
 
 

lib-sql/tokenizer/icu_tokenizer_tables.sql

@@ -1,40 +0,0 @@
--- SPDX-License-Identifier: GPL-2.0-only
---
--- This file is part of Nominatim. (https://nominatim.org)
---
--- Copyright (C) 2022 by the Nominatim developer community.
--- For a full list of authors see the git log.
-
-DROP TABLE IF EXISTS word;
-CREATE TABLE word (
-  word_id INTEGER,
-  word_token text NOT NULL,
-  type text NOT NULL,
-  word text,
-  info jsonb
-) {{db.tablespace.search_data}};
-
-CREATE INDEX idx_word_word_token ON word
-    USING BTREE (word_token) {{db.tablespace.search_index}};
--- Used when updating country names from the boundary relation.
-CREATE INDEX idx_word_country_names ON word
-    USING btree(word) {{db.tablespace.address_index}}
-    WHERE type = 'C';
--- Used when inserting new postcodes on updates.
-CREATE INDEX idx_word_postcodes ON word
-    USING btree(word) {{db.tablespace.address_index}}
-    WHERE type = 'P';
--- Used when inserting full words.
-CREATE INDEX idx_word_full_word ON word
-    USING btree(word) {{db.tablespace.address_index}}
-    WHERE type = 'W';
--- Used when inserting analyzed housenumbers (exclude old-style entries).
-CREATE INDEX idx_word_housenumbers ON word
-    USING btree(word) {{db.tablespace.address_index}}
-    WHERE type = 'H' and word is not null;
-
-GRANT SELECT ON word TO "{{config.DATABASE_WEBUSER}}";
-
-DROP SEQUENCE IF EXISTS seq_word;
-CREATE SEQUENCE seq_word start 1;
-GRANT SELECT ON seq_word to "{{config.DATABASE_WEBUSER}}";

lib-sql/tokenizer/legacy_tokenizer.sql

@@ -41,10 +41,17 @@ AS $$
 $$ LANGUAGE SQL IMMUTABLE STRICT;
 
 
+CREATE OR REPLACE FUNCTION token_is_street_address(info JSONB)
+  RETURNS BOOLEAN
+AS $$
+  SELECT info->>'street' is not null or info->>'place_search' is null;
+$$ LANGUAGE SQL IMMUTABLE;
+
+
 CREATE OR REPLACE FUNCTION token_has_addr_street(info JSONB)
   RETURNS BOOLEAN
 AS $$
-  SELECT info->>'street' is not null;
+  SELECT info->>'street' is not null and info->>'street' != '{}';
 $$ LANGUAGE SQL IMMUTABLE;
 
 
@@ -340,7 +347,7 @@ BEGIN
       END LOOP;
     END IF;
 
-    -- consider parts before an opening braket a full word as well
+    -- consider parts before an opening bracket a full word as well
     words := regexp_split_to_array(value, E'[(]');
     IF array_upper(words, 1) > 1 THEN
       s := make_standard_name(words[1]);

man/create-manpage.tmpl

@@ -7,6 +7,6 @@ sys.path.append('@PROJECT_SOURCE_DIR@')
 from nominatim.cli import get_set_parser
 
 def get_parser():
-    parser = get_set_parser(phpcgi_path='@PHPCGI_BIN@')
+    parser = get_set_parser()
 
     return parser.parser

module/CMakeLists.txt

@@ -1,6 +1,6 @@
 # just use the pgxs makefile
 
-foreach(suffix ${PostgreSQL_ADDITIONAL_VERSIONS} "15" "14" "13" "12" "11" "10" "9.6")
+foreach(suffix ${PostgreSQL_ADDITIONAL_VERSIONS} "16" "15" "14" "13" "12" "11" "10" "9.6")
     list(APPEND PG_CONFIG_HINTS
          "/usr/pgsql-${suffix}/bin")
 endforeach()

module/nominatim.c

@@ -11,10 +11,12 @@
 #include "mb/pg_wchar.h"
 #include <utfasciitable.h>
 
-#ifdef PG_MODULE_MAGIC
-PG_MODULE_MAGIC;
+#if PG_MAJORVERSION_NUM > 15
+#include "varatt.h"
 #endif
 
+PG_MODULE_MAGIC;
+
 Datum transliteration( PG_FUNCTION_ARGS );
 Datum gettokenstring( PG_FUNCTION_ARGS );
 void str_replace(char* buffer, int* len, int* changes, char* from, int fromlen, char* to, int tolen, int);

nominatim/api/__init__.py

@@ -0,0 +1,38 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+The public interface of the Nominatim library.
+
+Classes and functions defined in this file are considered stable. Always
+import from this file, not from the source files directly.
+"""
+
+# See also https://github.com/PyCQA/pylint/issues/6006
+# pylint: disable=useless-import-alias
+
+from .core import (NominatimAPI as NominatimAPI,
+                   NominatimAPIAsync as NominatimAPIAsync)
+from .connection import (SearchConnection as SearchConnection)
+from .status import (StatusResult as StatusResult)
+from .types import (PlaceID as PlaceID,
+                    OsmID as OsmID,
+                    PlaceRef as PlaceRef,
+                    Point as Point,
+                    Bbox as Bbox,
+                    GeometryFormat as GeometryFormat,
+                    DataLayer as DataLayer)
+from .results import (SourceTable as SourceTable,
+                      AddressLine as AddressLine,
+                      AddressLines as AddressLines,
+                      WordInfo as WordInfo,
+                      WordInfos as WordInfos,
+                      DetailedResult as DetailedResult,
+                      ReverseResult as ReverseResult,
+                      ReverseResults as ReverseResults,
+                      SearchResult as SearchResult,
+                      SearchResults as SearchResults)
+from .localization import (Locales as Locales)

nominatim/api/connection.py

@@ -0,0 +1,149 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Extended SQLAlchemy connection class that also includes access to the schema.
+"""
+from typing import cast, Any, Mapping, Sequence, Union, Dict, Optional, Set, \
+                   Awaitable, Callable, TypeVar
+import asyncio
+
+import sqlalchemy as sa
+from sqlalchemy.ext.asyncio import AsyncConnection
+
+from nominatim.typing import SaFromClause
+from nominatim.db.sqlalchemy_schema import SearchTables
+from nominatim.db.sqlalchemy_types import Geometry
+from nominatim.api.logging import log
+
+T = TypeVar('T')
+
+class SearchConnection:
+    """ An extended SQLAlchemy connection class, that also contains
+        then table definitions. The underlying asynchronous SQLAlchemy
+        connection can be accessed with the 'connection' property.
+        The 't' property is the collection of Nominatim tables.
+    """
+
+    def __init__(self, conn: AsyncConnection,
+                 tables: SearchTables,
+                 properties: Dict[str, Any]) -> None:
+        self.connection = conn
+        self.t = tables # pylint: disable=invalid-name
+        self._property_cache = properties
+        self._classtables: Optional[Set[str]] = None
+        self.query_timeout: Optional[int] = None
+
+
+    def set_query_timeout(self, timeout: Optional[int]) -> None:
+        """ Set the timeout after which a query over this connection
+            is cancelled.
+        """
+        self.query_timeout = timeout
+
+
+    async def scalar(self, sql: sa.sql.base.Executable,
+                     params: Union[Mapping[str, Any], None] = None
+                    ) -> Any:
+        """ Execute a 'scalar()' query on the connection.
+        """
+        log().sql(self.connection, sql, params)
+        return await asyncio.wait_for(self.connection.scalar(sql, params), self.query_timeout)
+
+
+    async def execute(self, sql: 'sa.Executable',
+                      params: Union[Mapping[str, Any], Sequence[Mapping[str, Any]], None] = None
+                     ) -> 'sa.Result[Any]':
+        """ Execute a 'execute()' query on the connection.
+        """
+        log().sql(self.connection, sql, params)
+        return await asyncio.wait_for(self.connection.execute(sql, params), self.query_timeout)
+
+
+    async def get_property(self, name: str, cached: bool = True) -> str:
+        """ Get a property from Nominatim's property table.
+
+            Property values are normally cached so that they are only
+            retrieved from the database when they are queried for the
+            first time with this function. Set 'cached' to False to force
+            reading the property from the database.
+
+            Raises a ValueError if the property does not exist.
+        """
+        lookup_name = f'DBPROP:{name}'
+
+        if cached and lookup_name in self._property_cache:
+            return cast(str, self._property_cache[lookup_name])
+
+        sql = sa.select(self.t.properties.c.value)\
+            .where(self.t.properties.c.property == name)
+        value = await self.connection.scalar(sql)
+
+        if value is None:
+            raise ValueError(f"Property '{name}' not found in database.")
+
+        self._property_cache[lookup_name] = cast(str, value)
+
+        return cast(str, value)
+
+
+    async def get_db_property(self, name: str) -> Any:
+        """ Get a setting from the database. At the moment, only
+            'server_version', the version of the database software, can
+            be retrieved with this function.
+
+            Raises a ValueError if the property does not exist.
+        """
+        if name != 'server_version':
+            raise ValueError(f"DB setting '{name}' not found in database.")
+
+        return self._property_cache['DB:server_version']
+
+
+    async def get_cached_value(self, group: str, name: str,
+                               factory: Callable[[], Awaitable[T]]) -> T:
+        """ Access the cache for this Nominatim instance.
+            Each cache value needs to belong to a group and have a name.
+            This function is for internal API use only.
+
+            `factory` is an async callback function that produces
+            the value if it is not already cached.
+
+            Returns the cached value or the result of factory (also caching
+            the result).
+        """
+        full_name = f'{group}:{name}'
+
+        if full_name in self._property_cache:
+            return cast(T, self._property_cache[full_name])
+
+        value = await factory()
+        self._property_cache[full_name] = value
+
+        return value
+
+
+    async def get_class_table(self, cls: str, typ: str) -> Optional[SaFromClause]:
+        """ Lookup up if there is a classtype table for the given category
+            and return a SQLAlchemy table for it, if it exists.
+        """
+        if self._classtables is None:
+            res = await self.execute(sa.text("""SELECT tablename FROM pg_tables
+                                                WHERE tablename LIKE 'place_classtype_%'
+                                             """))
+            self._classtables = {r[0] for r in res}
+
+        tablename = f"place_classtype_{cls}_{typ}"
+
+        if tablename not in self._classtables:
+            return None
+
+        if tablename in self.t.meta.tables:
+            return self.t.meta.tables[tablename]
+
+        return sa.Table(tablename, self.t.meta,
+                        sa.Column('place_id', sa.BigInteger),
+                        sa.Column('centroid', Geometry))

nominatim/api/core.py

@@ -0,0 +1,974 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Implementation of classes for API access via libraries.
+"""
+from typing import Mapping, Optional, Any, AsyncIterator, Dict, Sequence, List, Tuple
+import asyncio
+import sys
+import contextlib
+from pathlib import Path
+
+import sqlalchemy as sa
+import sqlalchemy.ext.asyncio as sa_asyncio
+
+from nominatim.errors import UsageError
+from nominatim.db.sqlalchemy_schema import SearchTables
+from nominatim.db.async_core_library import PGCORE_LIB, PGCORE_ERROR
+import nominatim.db.sqlite_functions
+from nominatim.config import Configuration
+from nominatim.api.connection import SearchConnection
+from nominatim.api.status import get_status, StatusResult
+from nominatim.api.lookup import get_detailed_place, get_simple_place
+from nominatim.api.reverse import ReverseGeocoder
+from nominatim.api.search import ForwardGeocoder, Phrase, PhraseType, make_query_analyzer
+import nominatim.api.types as ntyp
+from nominatim.api.results import DetailedResult, ReverseResult, SearchResults
+
+
+class NominatimAPIAsync: #pylint: disable=too-many-instance-attributes
+    """ The main frontend to the Nominatim database implements the
+        functions for lookup, forward and reverse geocoding using
+        asynchronous functions.
+
+        This class shares most of the functions with its synchronous
+        version. There are some additional functions or parameters,
+        which are documented below.
+    """
+    def __init__(self, project_dir: Path,
+                 environ: Optional[Mapping[str, str]] = None,
+                 loop: Optional[asyncio.AbstractEventLoop] = None) -> None:
+        """ Initiate a new frontend object with synchronous API functions.
+
+            Parameters:
+              project_dir: Path to the
+                  [project directory](../admin/Import.md#creating-the-project-directory)
+                  of the local Nominatim installation.
+              environ: Mapping of [configuration parameters](../customize/Settings.md).
+                  When set, replaces any configuration via environment variables.
+                  Settings in this mapping also have precedence over any
+                  parameters found in the `.env` file of the project directory.
+              loop: The asyncio event loop that will be used when calling
+                  functions. Only needed, when a custom event loop is used
+                  and the Python version is 3.9 or earlier.
+        """
+        self.config = Configuration(project_dir, environ)
+        self.query_timeout = self.config.get_int('QUERY_TIMEOUT') \
+                             if self.config.QUERY_TIMEOUT else None
+        self.reverse_restrict_to_country_area = self.config.get_bool('SEARCH_WITHIN_COUNTRIES')
+        self.server_version = 0
+
+        if sys.version_info >= (3, 10):
+            self._engine_lock = asyncio.Lock()
+        else:
+            self._engine_lock = asyncio.Lock(loop=loop) # pylint: disable=unexpected-keyword-arg
+        self._engine: Optional[sa_asyncio.AsyncEngine] = None
+        self._tables: Optional[SearchTables] = None
+        self._property_cache: Dict[str, Any] = {'DB:server_version': 0}
+
+
+    async def setup_database(self) -> None:
+        """ Set up the SQL engine and connections.
+
+            This function will be implicitly called when the database is
+            accessed for the first time. You may also call it explicitly to
+            avoid that the first call is delayed by the setup.
+        """
+        async with self._engine_lock:
+            if self._engine:
+                return
+
+            extra_args: Dict[str, Any] = {'future': True,
+                                          'echo': self.config.get_bool('DEBUG_SQL')}
+
+            if self.config.get_int('API_POOL_SIZE') == 0:
+                extra_args['poolclass'] = sa.pool.NullPool
+            else:
+                extra_args['poolclass'] = sa.pool.AsyncAdaptedQueuePool
+                extra_args['max_overflow'] = 0
+                extra_args['pool_size'] = self.config.get_int('API_POOL_SIZE')
+
+
+            is_sqlite = self.config.DATABASE_DSN.startswith('sqlite:')
+
+            if is_sqlite:
+                params = dict((p.split('=', 1)
+                              for p in self.config.DATABASE_DSN[7:].split(';')))
+                dburl = sa.engine.URL.create('sqlite+aiosqlite',
+                                             database=params.get('dbname'))
+
+                if not ('NOMINATIM_DATABASE_RW' in self.config.environ
+                        and self.config.get_bool('DATABASE_RW')) \
+                   and not Path(params.get('dbname', '')).is_file():
+                    raise UsageError(f"SQlite database '{params.get('dbname')}' does not exist.")
+            else:
+                dsn = self.config.get_database_params()
+                query = {k: v for k, v in dsn.items()
+                         if k not in ('user', 'password', 'dbname', 'host', 'port')}
+
+                dburl = sa.engine.URL.create(
+                           f'postgresql+{PGCORE_LIB}',
+                           database=dsn.get('dbname'),
+                           username=dsn.get('user'),
+                           password=dsn.get('password'),
+                           host=dsn.get('host'),
+                           port=int(dsn['port']) if 'port' in dsn else None,
+                           query=query)
+
+            engine = sa_asyncio.create_async_engine(dburl, **extra_args)
+
+            if is_sqlite:
+                server_version = 0
+
+                @sa.event.listens_for(engine.sync_engine, "connect")
+                def _on_sqlite_connect(dbapi_con: Any, _: Any) -> None:
+                    dbapi_con.run_async(lambda conn: conn.enable_load_extension(True))
+                    nominatim.db.sqlite_functions.install_custom_functions(dbapi_con)
+                    cursor = dbapi_con.cursor()
+                    cursor.execute("SELECT load_extension('mod_spatialite')")
+                    cursor.execute('SELECT SetDecimalPrecision(7)')
+                    dbapi_con.run_async(lambda conn: conn.enable_load_extension(False))
+            else:
+                try:
+                    async with engine.begin() as conn:
+                        result = await conn.scalar(sa.text('SHOW server_version_num'))
+                        server_version = int(result)
+                        if server_version >= 110000:
+                            await conn.execute(sa.text("SET jit_above_cost TO '-1'"))
+                            await conn.execute(sa.text(
+                                    "SET max_parallel_workers_per_gather TO '0'"))
+                except (PGCORE_ERROR, sa.exc.OperationalError):
+                    server_version = 0
+
+                if server_version >= 110000:
+                    @sa.event.listens_for(engine.sync_engine, "connect")
+                    def _on_connect(dbapi_con: Any, _: Any) -> None:
+                        cursor = dbapi_con.cursor()
+                        cursor.execute("SET jit_above_cost TO '-1'")
+                        cursor.execute("SET max_parallel_workers_per_gather TO '0'")
+
+            self._property_cache['DB:server_version'] = server_version
+
+            self._tables = SearchTables(sa.MetaData()) # pylint: disable=no-member
+            self._engine = engine
+
+
+    async def close(self) -> None:
+        """ Close all active connections to the database. The NominatimAPIAsync
+            object remains usable after closing. If a new API functions is
+            called, new connections are created.
+        """
+        if self._engine is not None:
+            await self._engine.dispose()
+
+
+    @contextlib.asynccontextmanager
+    async def begin(self) -> AsyncIterator[SearchConnection]:
+        """ Create a new connection with automatic transaction handling.
+
+            This function may be used to get low-level access to the database.
+            Refer to the documentation of SQLAlchemy for details how to use
+            the connection object.
+        """
+        if self._engine is None:
+            await self.setup_database()
+
+        assert self._engine is not None
+        assert self._tables is not None
+
+        async with self._engine.begin() as conn:
+            yield SearchConnection(conn, self._tables, self._property_cache)
+
+
+    async def status(self) -> StatusResult:
+        """ Return the status of the database.
+        """
+        try:
+            async with self.begin() as conn:
+                conn.set_query_timeout(self.query_timeout)
+                status = await get_status(conn)
+        except (PGCORE_ERROR, sa.exc.OperationalError):
+            return StatusResult(700, 'Database connection failed')
+
+        return status
+
+
+    async def details(self, place: ntyp.PlaceRef, **params: Any) -> Optional[DetailedResult]:
+        """ Get detailed information about a place in the database.
+
+            Returns None if there is no entry under the given ID.
+        """
+        details = ntyp.LookupDetails.from_kwargs(params)
+        async with self.begin() as conn:
+            conn.set_query_timeout(self.query_timeout)
+            if details.keywords:
+                await make_query_analyzer(conn)
+            return await get_detailed_place(conn, place, details)
+
+
+    async def lookup(self, places: Sequence[ntyp.PlaceRef], **params: Any) -> SearchResults:
+        """ Get simple information about a list of places.
+
+            Returns a list of place information for all IDs that were found.
+        """
+        details = ntyp.LookupDetails.from_kwargs(params)
+        async with self.begin() as conn:
+            conn.set_query_timeout(self.query_timeout)
+            if details.keywords:
+                await make_query_analyzer(conn)
+            return SearchResults(filter(None,
+                                        [await get_simple_place(conn, p, details) for p in places]))
+
+
+    async def reverse(self, coord: ntyp.AnyPoint, **params: Any) -> Optional[ReverseResult]:
+        """ Find a place by its coordinates. Also known as reverse geocoding.
+
+            Returns the closest result that can be found or None if
+            no place matches the given criteria.
+        """
+        # The following negation handles NaN correctly. Don't change.
+        if not abs(coord[0]) <= 180 or not abs(coord[1]) <= 90:
+            # There are no results to be expected outside valid coordinates.
+            return None
+
+        details = ntyp.ReverseDetails.from_kwargs(params)
+        async with self.begin() as conn:
+            conn.set_query_timeout(self.query_timeout)
+            if details.keywords:
+                await make_query_analyzer(conn)
+            geocoder = ReverseGeocoder(conn, details,
+                                       self.reverse_restrict_to_country_area)
+            return await geocoder.lookup(coord)
+
+
+    async def search(self, query: str, **params: Any) -> SearchResults:
+        """ Find a place by free-text search. Also known as forward geocoding.
+        """
+        query = query.strip()
+        if not query:
+            raise UsageError('Nothing to search for.')
+
+        async with self.begin() as conn:
+            conn.set_query_timeout(self.query_timeout)
+            geocoder = ForwardGeocoder(conn, ntyp.SearchDetails.from_kwargs(params),
+                                       self.config.get_int('REQUEST_TIMEOUT') \
+                                         if self.config.REQUEST_TIMEOUT else None)
+            phrases = [Phrase(PhraseType.NONE, p.strip()) for p in query.split(',')]
+            return await geocoder.lookup(phrases)
+
+
+    # pylint: disable=too-many-arguments,too-many-branches
+    async def search_address(self, amenity: Optional[str] = None,
+                             street: Optional[str] = None,
+                             city: Optional[str] = None,
+                             county: Optional[str] = None,
+                             state: Optional[str] = None,
+                             country: Optional[str] = None,
+                             postalcode: Optional[str] = None,
+                             **params: Any) -> SearchResults:
+        """ Find an address using structured search.
+        """
+        async with self.begin() as conn:
+            conn.set_query_timeout(self.query_timeout)
+            details = ntyp.SearchDetails.from_kwargs(params)
+
+            phrases: List[Phrase] = []
+
+            if amenity:
+                phrases.append(Phrase(PhraseType.AMENITY, amenity))
+            if street:
+                phrases.append(Phrase(PhraseType.STREET, street))
+            if city:
+                phrases.append(Phrase(PhraseType.CITY, city))
+            if county:
+                phrases.append(Phrase(PhraseType.COUNTY, county))
+            if state:
+                phrases.append(Phrase(PhraseType.STATE, state))
+            if postalcode:
+                phrases.append(Phrase(PhraseType.POSTCODE, postalcode))
+            if country:
+                phrases.append(Phrase(PhraseType.COUNTRY, country))
+
+            if not phrases:
+                raise UsageError('Nothing to search for.')
+
+            if amenity or street:
+                details.restrict_min_max_rank(26, 30)
+            elif city:
+                details.restrict_min_max_rank(13, 25)
+            elif county:
+                details.restrict_min_max_rank(10, 12)
+            elif state:
+                details.restrict_min_max_rank(5, 9)
+            elif postalcode:
+                details.restrict_min_max_rank(5, 11)
+            else:
+                details.restrict_min_max_rank(4, 4)
+
+            if 'layers' not in params:
+                details.layers = ntyp.DataLayer.ADDRESS
+                if amenity:
+                    details.layers |= ntyp.DataLayer.POI
+
+            geocoder = ForwardGeocoder(conn, details,
+                                       self.config.get_int('REQUEST_TIMEOUT') \
+                                         if self.config.REQUEST_TIMEOUT else None)
+            return await geocoder.lookup(phrases)
+
+
+    async def search_category(self, categories: List[Tuple[str, str]],
+                              near_query: Optional[str] = None,
+                              **params: Any) -> SearchResults:
+        """ Find an object of a certain category near another place.
+            The near place may either be given as an unstructured search
+            query in itself or as coordinates.
+        """
+        if not categories:
+            return SearchResults()
+
+        details = ntyp.SearchDetails.from_kwargs(params)
+        async with self.begin() as conn:
+            conn.set_query_timeout(self.query_timeout)
+            if near_query:
+                phrases = [Phrase(PhraseType.NONE, p) for p in near_query.split(',')]
+            else:
+                phrases = []
+                if details.keywords:
+                    await make_query_analyzer(conn)
+
+            geocoder = ForwardGeocoder(conn, details,
+                                       self.config.get_int('REQUEST_TIMEOUT') \
+                                         if self.config.REQUEST_TIMEOUT else None)
+            return await geocoder.lookup_pois(categories, phrases)
+
+
+
+class NominatimAPI:
+    """ This class provides a thin synchronous wrapper around the asynchronous
+        Nominatim functions. It creates its own event loop and runs each
+        synchronous function call to completion using that loop.
+    """
+
+    def __init__(self, project_dir: Path,
+                 environ: Optional[Mapping[str, str]] = None) -> None:
+        """ Initiate a new frontend object with synchronous API functions.
+
+            Parameters:
+              project_dir: Path to the
+                  [project directory](../admin/Import.md#creating-the-project-directory)
+                  of the local Nominatim installation.
+              environ: Mapping of [configuration parameters](../customize/Settings.md).
+                  When set, replaces any configuration via environment variables.
+                  Settings in this mapping also have precedence over any
+                  parameters found in the `.env` file of the project directory.
+        """
+        self._loop = asyncio.new_event_loop()
+        self._async_api = NominatimAPIAsync(project_dir, environ, loop=self._loop)
+
+
+    def close(self) -> None:
+        """ Close all active connections to the database.
+
+            This function also closes the asynchronous worker loop making
+            the NominatimAPI object unusable.
+        """
+        self._loop.run_until_complete(self._async_api.close())
+        self._loop.close()
+
+
+    @property
+    def config(self) -> Configuration:
+        """ Provide read-only access to the [configuration](#Configuration)
+            used by the API.
+        """
+        return self._async_api.config
+
+    def status(self) -> StatusResult:
+        """ Return the status of the database as a dataclass object
+            with the fields described below.
+
+            Returns:
+              status(int): A status code as described on the status page.
+              message(str): Either 'OK' or a human-readable message of the
+                  problem encountered.
+              software_version(tuple): A tuple with the version of the
+                  Nominatim library consisting of (major, minor, patch, db-patch)
+                  version.
+              database_version(tuple): A tuple with the version of the library
+                  which was used for the import or last migration.
+                  Also consists of (major, minor, patch, db-patch).
+              data_updated(datetime): Timestamp with the age of the data.
+        """
+        return self._loop.run_until_complete(self._async_api.status())
+
+
+    def details(self, place: ntyp.PlaceRef, **params: Any) -> Optional[DetailedResult]:
+        """ Get detailed information about a place in the database.
+
+            The result is a dataclass object with the fields described below
+            or `None` if the place could not be found in the database.
+
+            Parameters:
+              place: Description of the place to look up. See
+                     [Place identification](Input-Parameter-Types.md#place-identification)
+                     for the various ways to reference a place.
+
+            Other parameters:
+              geometry_output (enum): Add the full geometry of the place to the result.
+                Multiple formats may be selected. Note that geometries can become
+                quite large. (Default: none)
+              geometry_simplification (float): Simplification factor to use on
+                the geometries before returning them. The factor expresses
+                the tolerance in degrees from which the geometry may differ.
+                Topology is preserved. (Default: 0.0)
+              address_details (bool): Add detailed information about the places
+                that make up the address of the requested object. (Default: False)
+              linked_places (bool): Add detailed information about the places
+                that link to the result. (Default: False)
+              parented_places (bool): Add detailed information about all places
+                for which the requested object is a parent, i.e. all places for
+                which the object provides the address details.
+                Only POI places can have parents. (Default: False)
+              keywords (bool): Add detailed information about the search terms
+                used for this place.
+
+            Returns:
+              source_table (enum): Data source of the place. See below for possible values.
+              category (tuple): A tuple of two strings with the primary OSM tag
+                  and value.
+              centroid (Point): Point position of the place.
+              place_id (Optional[int]): Internal ID of the place. This ID may differ
+                  for the same place between different installations.
+              parent_place_id (Optional(int]): Internal ID of the parent of this
+                  place. Only meaning full for POI-like objects (places with a
+                  rank_address of 30).
+              linked_place_id (Optional[int]): Internal ID of the place this object
+                  links to. When this ID is set then there is no guarantee that
+                  the rest of the result information is complete.
+              admin_level (int): Value of the `admin_level` OSM tag. Only meaningful
+                  for administrative boundary objects.
+              indexed_date (datetime): Timestamp when the place was last updated.
+              osm_object (Optional[tuple]): OSM type and ID of the place, if available.
+              names (Optional[dict]): Dictionary of names of the place. Keys are
+                  usually the corresponding OSM tag keys.
+              address (Optional[dict]): Dictionary of address parts directly
+                  attributed to the place. Keys are usually the corresponding
+                  OSM tag keys with the `addr:` prefix removed.
+              extratags (Optional[dict]): Dictionary of additional attributes for
+                  the place. Usually OSM tag keys and values.
+              housenumber (Optional[str]): House number of the place, normalised
+                  for lookup. To get the house number in its original spelling,
+                  use `address['housenumber']`.
+              postcode (Optional[str]): Computed postcode for the place. To get
+                  directly attributed postcodes, use `address['postcode']` instead.
+              wikipedia (Optional[str]): Reference to a wikipedia site for the place.
+                  The string has the format <language code>:<wikipedia title>.
+              rank_address (int): [Address rank](../customize/Ranking.md#address-rank).
+              rank_search (int): [Search rank](../customize/Ranking.md#search-rank).
+              importance (Optional[float]): Relative importance of the place. This is a measure
+                  how likely the place will be searched for.
+              country_code (Optional[str]): Country the feature is in as
+                  ISO 3166-1 alpha-2 country code.
+              address_rows (Optional[AddressLines]): List of places that make up the
+                  computed address. `None` when `address_details` parameter was False.
+              linked_rows (Optional[AddressLines]): List of places that link to the object.
+                  `None` when `linked_places` parameter was False.
+              parented_rows (Optional[AddressLines]): List of direct children of the place.
+                  `None` when `parented_places` parameter was False.
+              name_keywords (Optional[WordInfos]): List of search words for the name of
+                   the place. `None` when `keywords` parameter is set to False.
+              address_keywords (Optional[WordInfos]): List of search word for the address of
+                   the place. `None` when `keywords` parameter is set to False.
+              geometry (dict): Dictionary containing the full geometry of the place
+                   in the formats requested in the `geometry_output` parameter.
+        """
+        return self._loop.run_until_complete(self._async_api.details(place, **params))
+
+
+    def lookup(self, places: Sequence[ntyp.PlaceRef], **params: Any) -> SearchResults:
+        """ Get simple information about a list of places.
+
+            Returns a list of place information for all IDs that were found.
+            Each result is a dataclass with the fields detailed below.
+
+            Parameters:
+              places: List of descriptions of the place to look up. See
+                      [Place identification](Input-Parameter-Types.md#place-identification)
+                      for the various ways to reference a place.
+
+            Other parameters:
+              geometry_output (enum): Add the full geometry of the place to the result.
+                Multiple formats may be selected. Note that geometries can become
+                quite large. (Default: none)
+              geometry_simplification (float): Simplification factor to use on
+                the geometries before returning them. The factor expresses
+                the tolerance in degrees from which the geometry may differ.
+                Topology is preserved. (Default: 0.0)
+              address_details (bool): Add detailed information about the places
+                that make up the address of the requested object. (Default: False)
+              linked_places (bool): Add detailed information about the places
+                that link to the result. (Default: False)
+              parented_places (bool): Add detailed information about all places
+                for which the requested object is a parent, i.e. all places for
+                which the object provides the address details.
+                Only POI places can have parents. (Default: False)
+              keywords (bool): Add detailed information about the search terms
+                used for this place.
+
+            Returns:
+              source_table (enum): Data source of the place. See below for possible values.
+              category (tuple): A tuple of two strings with the primary OSM tag
+                  and value.
+              centroid (Point): Point position of the place.
+              place_id (Optional[int]): Internal ID of the place. This ID may differ
+                  for the same place between different installations.
+              osm_object (Optional[tuple]): OSM type and ID of the place, if available.
+              names (Optional[dict]): Dictionary of names of the place. Keys are
+                  usually the corresponding OSM tag keys.
+              address (Optional[dict]): Dictionary of address parts directly
+                  attributed to the place. Keys are usually the corresponding
+                  OSM tag keys with the `addr:` prefix removed.
+              extratags (Optional[dict]): Dictionary of additional attributes for
+                  the place. Usually OSM tag keys and values.
+              housenumber (Optional[str]): House number of the place, normalised
+                  for lookup. To get the house number in its original spelling,
+                  use `address['housenumber']`.
+              postcode (Optional[str]): Computed postcode for the place. To get
+                  directly attributed postcodes, use `address['postcode']` instead.
+              wikipedia (Optional[str]): Reference to a wikipedia site for the place.
+                  The string has the format <language code>:<wikipedia title>.
+              rank_address (int): [Address rank](../customize/Ranking.md#address-rank).
+              rank_search (int): [Search rank](../customize/Ranking.md#search-rank).
+              importance (Optional[float]): Relative importance of the place. This is a measure
+                  how likely the place will be searched for.
+              country_code (Optional[str]): Country the feature is in as
+                  ISO 3166-1 alpha-2 country code.
+              address_rows (Optional[AddressLines]): List of places that make up the
+                  computed address. `None` when `address_details` parameter was False.
+              linked_rows (Optional[AddressLines]): List of places that link to the object.
+                  `None` when `linked_places` parameter was False.
+              parented_rows (Optional[AddressLines]): List of direct children of the place.
+                  `None` when `parented_places` parameter was False.
+              name_keywords (Optional[WordInfos]): List of search words for the name of
+                   the place. `None` when `keywords` parameter is set to False.
+              address_keywords (Optional[WordInfos]): List of search word for the address of
+                   the place. `None` when `keywords` parameter is set to False.
+              bbox (Bbox): Bounding box of the full geometry of the place.
+                   If the place is a single point, then the size of the bounding
+                   box is guessed according to the type of place.
+              geometry (dict): Dictionary containing the full geometry of the place
+                   in the formats requested in the `geometry_output` parameter.
+        """
+        return self._loop.run_until_complete(self._async_api.lookup(places, **params))
+
+
+    def reverse(self, coord: ntyp.AnyPoint, **params: Any) -> Optional[ReverseResult]:
+        """ Find a place by its coordinates. Also known as reverse geocoding.
+
+            Returns the closest result that can be found or `None` if
+            no place matches the given criteria. The result is a dataclass
+            with the fields as detailed below.
+
+            Parameters:
+              coord: Coordinate to lookup the place for as a Point
+                     or a tuple (x, y). Must be in WGS84 projection.
+
+            Other parameters:
+              max_rank (int): Highest address rank to return. Can be used to
+                restrict search to streets or settlements.
+              layers (enum): Defines the kind of data to take into account.
+                See description of layers below. (Default: addresses and POIs)
+              geometry_output (enum): Add the full geometry of the place to the result.
+                Multiple formats may be selected. Note that geometries can become
+                quite large. (Default: none)
+              geometry_simplification (float): Simplification factor to use on
+                the geometries before returning them. The factor expresses
+                the tolerance in degrees from which the geometry may differ.
+                Topology is preserved. (Default: 0.0)
+              address_details (bool): Add detailed information about the places
+                that make up the address of the requested object. (Default: False)
+              linked_places (bool): Add detailed information about the places
+                that link to the result. (Default: False)
+              parented_places (bool): Add detailed information about all places
+                for which the requested object is a parent, i.e. all places for
+                which the object provides the address details.
+                Only POI places can have parents. (Default: False)
+              keywords (bool): Add detailed information about the search terms
+                used for this place.
+
+            Returns:
+              source_table (enum): Data source of the place. See below for possible values.
+              category (tuple): A tuple of two strings with the primary OSM tag
+                  and value.
+              centroid (Point): Point position of the place.
+              place_id (Optional[int]): Internal ID of the place. This ID may differ
+                  for the same place between different installations.
+              osm_object (Optional[tuple]): OSM type and ID of the place, if available.
+              names (Optional[dict]): Dictionary of names of the place. Keys are
+                  usually the corresponding OSM tag keys.
+              address (Optional[dict]): Dictionary of address parts directly
+                  attributed to the place. Keys are usually the corresponding
+                  OSM tag keys with the `addr:` prefix removed.
+              extratags (Optional[dict]): Dictionary of additional attributes for
+                  the place. Usually OSM tag keys and values.
+              housenumber (Optional[str]): House number of the place, normalised
+                  for lookup. To get the house number in its original spelling,
+                  use `address['housenumber']`.
+              postcode (Optional[str]): Computed postcode for the place. To get
+                  directly attributed postcodes, use `address['postcode']` instead.
+              wikipedia (Optional[str]): Reference to a wikipedia site for the place.
+                  The string has the format <language code>:<wikipedia title>.
+              rank_address (int): [Address rank](../customize/Ranking.md#address-rank).
+              rank_search (int): [Search rank](../customize/Ranking.md#search-rank).
+              importance (Optional[float]): Relative importance of the place. This is a measure
+                  how likely the place will be searched for.
+              country_code (Optional[str]): Country the feature is in as
+                  ISO 3166-1 alpha-2 country code.
+              address_rows (Optional[AddressLines]): List of places that make up the
+                  computed address. `None` when `address_details` parameter was False.
+              linked_rows (Optional[AddressLines]): List of places that link to the object.
+                  `None` when `linked_places` parameter was False.
+              parented_rows (Optional[AddressLines]): List of direct children of the place.
+                  `None` when `parented_places` parameter was False.
+              name_keywords (Optional[WordInfos]): List of search words for the name of
+                   the place. `None` when `keywords` parameter is set to False.
+              address_keywords (Optional[WordInfos]): List of search word for the address of
+                   the place. `None` when `keywords` parameter is set to False.
+              bbox (Bbox): Bounding box of the full geometry of the place.
+                   If the place is a single point, then the size of the bounding
+                   box is guessed according to the type of place.
+              geometry (dict): Dictionary containing the full geometry of the place
+                   in the formats requested in the `geometry_output` parameter.
+              distance (Optional[float]): Distance in degree from the input point.
+        """
+        return self._loop.run_until_complete(self._async_api.reverse(coord, **params))
+
+
+    def search(self, query: str, **params: Any) -> SearchResults:
+        """ Find a place by free-text search. Also known as forward geocoding.
+
+            Parameters:
+              query: Free-form text query searching for a place.
+
+            Other parameters:
+              max_results (int): Maximum number of results to return. The
+                actual number of results may be less. (Default: 10)
+              min_rank (int): Lowest permissible rank for the result.
+                For addressable places this is the minimum
+                [address rank](../customize/Ranking.md#address-rank). For all
+                other places the [search rank](../customize/Ranking.md#search-rank)
+                is used.
+              max_rank (int): Highest permissible rank for the result. See min_rank above.
+              layers (enum): Defines the kind of data to take into account.
+                See [layers section](Input-Parameter-Types.md#layers) for details.
+                (Default: addresses and POIs)
+              countries (list[str]): Restrict search to countries with the given
+                ISO 3166-1 alpha-2 country code. An empty list (the default)
+                disables this filter.
+              excluded (list[int]): A list of internal IDs of places to exclude
+                from the search.
+              viewbox (Optional[Bbox]): Bounding box of an area to focus search on.
+              bounded_viewbox (bool): Consider the bounding box given in `viewbox`
+                as a filter and return only results within the bounding box.
+              near (Optional[Point]): Focus search around the given point and
+                return results ordered by distance to the given point.
+              near_radius (Optional[float]): Restrict results to results within
+                the given distance in degrees of `near` point. Ignored, when
+                `near` is not set.
+              categories (list[tuple]): Restrict search to places of the given
+                categories. The category is the main OSM tag assigned to each
+                place. An empty list (the default) disables this filter.
+              geometry_output (enum): Add the full geometry of the place to the result.
+                Multiple formats may be selected. Note that geometries can become
+                quite large. (Default: none)
+              geometry_simplification (float): Simplification factor to use on
+                the geometries before returning them. The factor expresses
+                the tolerance in degrees from which the geometry may differ.
+                Topology is preserved. (Default: 0.0)
+              address_details (bool): Add detailed information about the places
+                that make up the address of the requested object. (Default: False)
+              linked_places (bool): Add detailed information about the places
+                that link to the result. (Default: False)
+              parented_places (bool): Add detailed information about all places
+                for which the requested object is a parent, i.e. all places for
+                which the object provides the address details.
+                Only POI places can have parents. (Default: False)
+              keywords (bool): Add detailed information about the search terms
+                used for this place.
+
+            Returns:
+              source_table (enum): Data source of the place. See below for possible values.
+              category (tuple): A tuple of two strings with the primary OSM tag
+                  and value.
+              centroid (Point): Point position of the place.
+              place_id (Optional[int]): Internal ID of the place. This ID may differ
+                  for the same place between different installations.
+              osm_object (Optional[tuple]): OSM type and ID of the place, if available.
+              names (Optional[dict]): Dictionary of names of the place. Keys are
+                  usually the corresponding OSM tag keys.
+              address (Optional[dict]): Dictionary of address parts directly
+                  attributed to the place. Keys are usually the corresponding
+                  OSM tag keys with the `addr:` prefix removed.
+              extratags (Optional[dict]): Dictionary of additional attributes for
+                  the place. Usually OSM tag keys and values.
+              housenumber (Optional[str]): House number of the place, normalised
+                  for lookup. To get the house number in its original spelling,
+                  use `address['housenumber']`.
+              postcode (Optional[str]): Computed postcode for the place. To get
+                  directly attributed postcodes, use `address['postcode']` instead.
+              wikipedia (Optional[str]): Reference to a wikipedia site for the place.
+                  The string has the format <language code>:<wikipedia title>.
+              rank_address (int): [Address rank](../customize/Ranking.md#address-rank).
+              rank_search (int): [Search rank](../customize/Ranking.md#search-rank).
+              importance (Optional[float]): Relative importance of the place. This is a measure
+                  how likely the place will be searched for.
+              country_code (Optional[str]): Country the feature is in as
+                  ISO 3166-1 alpha-2 country code.
+              address_rows (Optional[AddressLines]): List of places that make up the
+                  computed address. `None` when `address_details` parameter was False.
+              linked_rows (Optional[AddressLines]): List of places that link to the object.
+                  `None` when `linked_places` parameter was False.
+              parented_rows (Optional[AddressLines]): List of direct children of the place.
+                  `None` when `parented_places` parameter was False.
+              name_keywords (Optional[WordInfos]): List of search words for the name of
+                   the place. `None` when `keywords` parameter is set to False.
+              address_keywords (Optional[WordInfos]): List of search word for the address of
+                   the place. `None` when `keywords` parameter is set to False.
+              bbox (Bbox): Bounding box of the full geometry of the place.
+                   If the place is a single point, then the size of the bounding
+                   box is guessed according to the type of place.
+              geometry (dict): Dictionary containing the full geometry of the place
+                   in the formats requested in the `geometry_output` parameter.
+        """
+        return self._loop.run_until_complete(
+                   self._async_api.search(query, **params))
+
+
+    # pylint: disable=too-many-arguments
+    def search_address(self, amenity: Optional[str] = None,
+                       street: Optional[str] = None,
+                       city: Optional[str] = None,
+                       county: Optional[str] = None,
+                       state: Optional[str] = None,
+                       country: Optional[str] = None,
+                       postalcode: Optional[str] = None,
+                       **params: Any) -> SearchResults:
+        """ Find an address using structured search.
+
+            Parameters:
+              amenity: Name of a POI.
+              street: Street and optionally housenumber of the address. If the address
+                does not have a street, then the place the housenumber references to.
+              city: Postal city of the address.
+              county: County equivalent of the address. Does not exist in all
+                jurisdictions.
+              state: State or province of the address.
+              country: Country with its full name or its ISO 3166-1 alpha-2 country code.
+                Do not use together with the country_code filter.
+              postalcode: Post code or ZIP for the place.
+
+            Other parameters:
+              max_results (int): Maximum number of results to return. The
+                actual number of results may be less. (Default: 10)
+              min_rank (int): Lowest permissible rank for the result.
+                For addressable places this is the minimum
+                [address rank](../customize/Ranking.md#address-rank). For all
+                other places the [search rank](../customize/Ranking.md#search-rank)
+                is used.
+              max_rank (int): Highest permissible rank for the result. See min_rank above.
+              layers (enum): Defines the kind of data to take into account.
+                See [layers section](Input-Parameter-Types.md#layers) for details.
+                (Default: addresses and POIs)
+              countries (list[str]): Restrict search to countries with the given
+                ISO 3166-1 alpha-2 country code. An empty list (the default)
+                disables this filter. Do not use, when the country parameter
+                is used.
+              excluded (list[int]): A list of internal IDs of places to exclude
+                from the search.
+              viewbox (Optional[Bbox]): Bounding box of an area to focus search on.
+              bounded_viewbox (bool): Consider the bounding box given in `viewbox`
+                as a filter and return only results within the bounding box.
+              near (Optional[Point]): Focus search around the given point and
+                return results ordered by distance to the given point.
+              near_radius (Optional[float]): Restrict results to results within
+                the given distance in degrees of `near` point. Ignored, when
+                `near` is not set.
+              categories (list[tuple]): Restrict search to places of the given
+                categories. The category is the main OSM tag assigned to each
+                place. An empty list (the default) disables this filter.
+              geometry_output (enum): Add the full geometry of the place to the result.
+                Multiple formats may be selected. Note that geometries can become
+                quite large. (Default: none)
+              geometry_simplification (float): Simplification factor to use on
+                the geometries before returning them. The factor expresses
+                the tolerance in degrees from which the geometry may differ.
+                Topology is preserved. (Default: 0.0)
+              address_details (bool): Add detailed information about the places
+                that make up the address of the requested object. (Default: False)
+              linked_places (bool): Add detailed information about the places
+                that link to the result. (Default: False)
+              parented_places (bool): Add detailed information about all places
+                for which the requested object is a parent, i.e. all places for
+                which the object provides the address details.
+                Only POI places can have parents. (Default: False)
+              keywords (bool): Add detailed information about the search terms
+                used for this place.
+
+            Returns:
+              source_table (enum): Data source of the place. See below for possible values.
+              category (tuple): A tuple of two strings with the primary OSM tag
+                  and value.
+              centroid (Point): Point position of the place.
+              place_id (Optional[int]): Internal ID of the place. This ID may differ
+                  for the same place between different installations.
+              osm_object (Optional[tuple]): OSM type and ID of the place, if available.
+              names (Optional[dict]): Dictionary of names of the place. Keys are
+                  usually the corresponding OSM tag keys.
+              address (Optional[dict]): Dictionary of address parts directly
+                  attributed to the place. Keys are usually the corresponding
+                  OSM tag keys with the `addr:` prefix removed.
+              extratags (Optional[dict]): Dictionary of additional attributes for
+                  the place. Usually OSM tag keys and values.
+              housenumber (Optional[str]): House number of the place, normalised
+                  for lookup. To get the house number in its original spelling,
+                  use `address['housenumber']`.
+              postcode (Optional[str]): Computed postcode for the place. To get
+                  directly attributed postcodes, use `address['postcode']` instead.
+              wikipedia (Optional[str]): Reference to a wikipedia site for the place.
+                  The string has the format <language code>:<wikipedia title>.
+              rank_address (int): [Address rank](../customize/Ranking.md#address-rank).
+              rank_search (int): [Search rank](../customize/Ranking.md#search-rank).
+              importance (Optional[float]): Relative importance of the place. This is a measure
+                  how likely the place will be searched for.
+              country_code (Optional[str]): Country the feature is in as
+                  ISO 3166-1 alpha-2 country code.
+              address_rows (Optional[AddressLines]): List of places that make up the
+                  computed address. `None` when `address_details` parameter was False.
+              linked_rows (Optional[AddressLines]): List of places that link to the object.
+                  `None` when `linked_places` parameter was False.
+              parented_rows (Optional[AddressLines]): List of direct children of the place.
+                  `None` when `parented_places` parameter was False.
+              name_keywords (Optional[WordInfos]): List of search words for the name of
+                   the place. `None` when `keywords` parameter is set to False.
+              address_keywords (Optional[WordInfos]): List of search word for the address of
+                   the place. `None` when `keywords` parameter is set to False.
+              bbox (Bbox): Bounding box of the full geometry of the place.
+                   If the place is a single point, then the size of the bounding
+                   box is guessed according to the type of place.
+              geometry (dict): Dictionary containing the full geometry of the place
+                   in the formats requested in the `geometry_output` parameter.
+        """
+        return self._loop.run_until_complete(
+                   self._async_api.search_address(amenity, street, city, county,
+                                                  state, country, postalcode, **params))
+
+
+    def search_category(self, categories: List[Tuple[str, str]],
+                        near_query: Optional[str] = None,
+                        **params: Any) -> SearchResults:
+        """ Find an object of a certain category near another place.
+
+            The near place may either be given as an unstructured search
+            query in itself or as a geographic area through the
+            viewbox or near parameters.
+
+            Parameters:
+              categories: Restrict search to places of the given
+                categories. The category is the main OSM tag assigned to each
+                place.
+              near_query: Optional free-text query to define the are to
+                restrict search to.
+
+            Other parameters:
+              max_results (int): Maximum number of results to return. The
+                actual number of results may be less. (Default: 10)
+              min_rank (int): Lowest permissible rank for the result.
+                For addressable places this is the minimum
+                [address rank](../customize/Ranking.md#address-rank). For all
+                other places the [search rank](../customize/Ranking.md#search-rank)
+                is used.
+              max_rank (int): Highest permissible rank for the result. See min_rank above.
+              layers (enum): Defines the kind of data to take into account.
+                See [layers section](Input-Parameter-Types.md#layers) for details.
+                (Default: addresses and POIs)
+              countries (list[str]): Restrict search to countries with the given
+                ISO 3166-1 alpha-2 country code. An empty list (the default)
+                disables this filter.
+              excluded (list[int]): A list of internal IDs of places to exclude
+                from the search.
+              viewbox (Optional[Bbox]): Bounding box of an area to focus search on.
+              bounded_viewbox (bool): Consider the bounding box given in `viewbox`
+                as a filter and return only results within the bounding box.
+              near (Optional[Point]): Focus search around the given point and
+                return results ordered by distance to the given point.
+              near_radius (Optional[float]): Restrict results to results within
+                the given distance in degrees of `near` point. Ignored, when
+                `near` is not set.
+              geometry_output (enum): Add the full geometry of the place to the result.
+                Multiple formats may be selected. Note that geometries can become
+                quite large. (Default: none)
+              geometry_simplification (float): Simplification factor to use on
+                the geometries before returning them. The factor expresses
+                the tolerance in degrees from which the geometry may differ.
+                Topology is preserved. (Default: 0.0)
+              address_details (bool): Add detailed information about the places
+                that make up the address of the requested object. (Default: False)
+              linked_places (bool): Add detailed information about the places
+                that link to the result. (Default: False)
+              parented_places (bool): Add detailed information about all places
+                for which the requested object is a parent, i.e. all places for
+                which the object provides the address details.
+                Only POI places can have parents. (Default: False)
+              keywords (bool): Add detailed information about the search terms
+                used for this place.
+
+            Returns:
+              source_table (enum): Data source of the place. See below for possible values.
+              category (tuple): A tuple of two strings with the primary OSM tag
+                  and value.
+              centroid (Point): Point position of the place.
+              place_id (Optional[int]): Internal ID of the place. This ID may differ
+                  for the same place between different installations.
+              osm_object (Optional[tuple]): OSM type and ID of the place, if available.
+              names (Optional[dict]): Dictionary of names of the place. Keys are
+                  usually the corresponding OSM tag keys.
+              address (Optional[dict]): Dictionary of address parts directly
+                  attributed to the place. Keys are usually the corresponding
+                  OSM tag keys with the `addr:` prefix removed.
+              extratags (Optional[dict]): Dictionary of additional attributes for
+                  the place. Usually OSM tag keys and values.
+              housenumber (Optional[str]): House number of the place, normalised
+                  for lookup. To get the house number in its original spelling,
+                  use `address['housenumber']`.
+              postcode (Optional[str]): Computed postcode for the place. To get
+                  directly attributed postcodes, use `address['postcode']` instead.
+              wikipedia (Optional[str]): Reference to a wikipedia site for the place.
+                  The string has the format <language code>:<wikipedia title>.
+              rank_address (int): [Address rank](../customize/Ranking.md#address-rank).
+              rank_search (int): [Search rank](../customize/Ranking.md#search-rank).
+              importance (Optional[float]): Relative importance of the place. This is a measure
+                  how likely the place will be searched for.
+              country_code (Optional[str]): Country the feature is in as
+                  ISO 3166-1 alpha-2 country code.
+              address_rows (Optional[AddressLines]): List of places that make up the
+                  computed address. `None` when `address_details` parameter was False.
+              linked_rows (Optional[AddressLines]): List of places that link to the object.
+                  `None` when `linked_places` parameter was False.
+              parented_rows (Optional[AddressLines]): List of direct children of the place.
+                  `None` when `parented_places` parameter was False.
+              name_keywords (Optional[WordInfos]): List of search words for the name of
+                   the place. `None` when `keywords` parameter is set to False.
+              address_keywords (Optional[WordInfos]): List of search word for the address of
+                   the place. `None` when `keywords` parameter is set to False.
+              bbox (Bbox): Bounding box of the full geometry of the place.
+                   If the place is a single point, then the size of the bounding
+                   box is guessed according to the type of place.
+              geometry (dict): Dictionary containing the full geometry of the place
+                   in the formats requested in the `geometry_output` parameter.
+        """
+        return self._loop.run_until_complete(
+                   self._async_api.search_category(categories, near_query, **params))

nominatim/api/localization.py

@@ -0,0 +1,97 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Helper functions for localizing names of results.
+"""
+from typing import Mapping, List, Optional
+
+import re
+
+class Locales:
+    """ Helper class for localization of names.
+
+        It takes a list of language prefixes in their order of preferred
+        usage.
+    """
+
+    def __init__(self, langs: Optional[List[str]] = None):
+        self.languages = langs or []
+        self.name_tags: List[str] = []
+
+        # Build the list of supported tags. It is currently hard-coded.
+        self._add_lang_tags('name')
+        self._add_tags('name', 'brand')
+        self._add_lang_tags('official_name', 'short_name')
+        self._add_tags('official_name', 'short_name', 'ref')
+
+
+    def __bool__(self) -> bool:
+        return len(self.languages) > 0
+
+
+    def _add_tags(self, *tags: str) -> None:
+        for tag in tags:
+            self.name_tags.append(tag)
+            self.name_tags.append(f"_place_{tag}")
+
+
+    def _add_lang_tags(self, *tags: str) -> None:
+        for tag in tags:
+            for lang in self.languages:
+                self.name_tags.append(f"{tag}:{lang}")
+                self.name_tags.append(f"_place_{tag}:{lang}")
+
+
+    def display_name(self, names: Optional[Mapping[str, str]]) -> str:
+        """ Return the best matching name from a dictionary of names
+            containing different name variants.
+
+            If 'names' is null or empty, an empty string is returned. If no
+            appropriate localization is found, the first name is returned.
+        """
+        if not names:
+            return ''
+
+        if len(names) > 1:
+            for tag in self.name_tags:
+                if tag in names:
+                    return names[tag]
+
+        # Nothing? Return any of the other names as a default.
+        return next(iter(names.values()))
+
+
+    @staticmethod
+    def from_accept_languages(langstr: str) -> 'Locales':
+        """ Create a localization object from a language list in the
+            format of HTTP accept-languages header.
+
+            The functions tries to be forgiving of format errors by first splitting
+            the string into comma-separated parts and then parsing each
+            description separately. Badly formatted parts are then ignored.
+        """
+        # split string into languages
+        candidates = []
+        for desc in langstr.split(','):
+            m = re.fullmatch(r'\s*([a-z_-]+)(?:;\s*q\s*=\s*([01](?:\.\d+)?))?\s*',
+                             desc, flags=re.I)
+            if m:
+                candidates.append((m[1], float(m[2] or 1.0)))
+
+        # sort the results by the weight of each language (preserving order).
+        candidates.sort(reverse=True, key=lambda e: e[1])
+
+        # If a language has a region variant, also add the language without
+        # variant but only if it isn't already in the list to not mess up the weight.
+        languages = []
+        for lid, _ in candidates:
+            languages.append(lid)
+            parts = lid.split('-', 1)
+            if len(parts) > 1 and all(c[0] != parts[0] for c in candidates):
+                languages.append(parts[0])
+
+        return Locales(languages)

nominatim/api/logging.py

@@ -0,0 +1,433 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Functions for specialised logging with HTML output.
+"""
+from typing import Any, Iterator, Optional, List, Tuple, cast, Union, Mapping, Sequence
+from contextvars import ContextVar
+import datetime as dt
+import textwrap
+import io
+import re
+import html
+
+import sqlalchemy as sa
+from sqlalchemy.ext.asyncio import AsyncConnection
+
+try:
+    from pygments import highlight
+    from pygments.lexers import PythonLexer, PostgresLexer
+    from pygments.formatters import HtmlFormatter
+    CODE_HIGHLIGHT = True
+except ModuleNotFoundError:
+    CODE_HIGHLIGHT = False
+
+
+def _debug_name(res: Any) -> str:
+    if res.names:
+        return cast(str, res.names.get('name', next(iter(res.names.values()))))
+
+    return f"Hnr {res.housenumber}" if res.housenumber is not None else '[NONE]'
+
+
+class BaseLogger:
+    """ Interface for logging function.
+
+        The base implementation does nothing. Overwrite the functions
+        in derived classes which implement logging functionality.
+    """
+    def get_buffer(self) -> str:
+        """ Return the current content of the log buffer.
+        """
+        return ''
+
+    def function(self, func: str, **kwargs: Any) -> None:
+        """ Start a new debug chapter for the given function and its parameters.
+        """
+
+
+    def section(self, heading: str) -> None:
+        """ Start a new section with the given title.
+        """
+
+
+    def comment(self, text: str) -> None:
+        """ Add a simple comment to the debug output.
+        """
+
+
+    def var_dump(self, heading: str, var: Any) -> None:
+        """ Print the content of the variable to the debug output prefixed by
+            the given heading.
+        """
+
+
+    def table_dump(self, heading: str, rows: Iterator[Optional[List[Any]]]) -> None:
+        """ Print the table generated by the generator function.
+        """
+
+
+    def result_dump(self, heading: str, results: Iterator[Tuple[Any, Any]]) -> None:
+        """ Print a list of search results generated by the generator function.
+        """
+
+
+    def sql(self, conn: AsyncConnection, statement: 'sa.Executable',
+            params: Union[Mapping[str, Any], Sequence[Mapping[str, Any]], None]) -> None:
+        """ Print the SQL for the given statement.
+        """
+
+    def format_sql(self, conn: AsyncConnection, statement: 'sa.Executable',
+                   extra_params: Union[Mapping[str, Any],
+                                 Sequence[Mapping[str, Any]], None]) -> str:
+        """ Return the compiled version of the statement.
+        """
+        compiled = cast('sa.ClauseElement', statement).compile(conn.sync_engine)
+
+        params = dict(compiled.params)
+        if isinstance(extra_params, Mapping):
+            for k, v in extra_params.items():
+                if hasattr(v, 'to_wkt'):
+                    params[k] = v.to_wkt()
+                elif isinstance(v, (int, float)):
+                    params[k] = v
+                else:
+                    params[k] = str(v)
+        elif isinstance(extra_params, Sequence) and extra_params:
+            for k in extra_params[0]:
+                params[k] = f':{k}'
+
+        sqlstr = str(compiled)
+
+        if conn.dialect.name == 'postgresql':
+            if sa.__version__.startswith('1'):
+                try:
+                    sqlstr = re.sub(r'__\[POSTCOMPILE_[^]]*\]', '%s', sqlstr)
+                    return sqlstr % tuple((repr(params.get(name, None))
+                                          for name in compiled.positiontup)) # type: ignore
+                except TypeError:
+                    return sqlstr
+
+            # Fixes an odd issue with Python 3.7 where percentages are not
+            # quoted correctly.
+            sqlstr = re.sub(r'%(?!\()', '%%', sqlstr)
+            sqlstr = re.sub(r'__\[POSTCOMPILE_([^]]*)\]', r'%(\1)s', sqlstr)
+            return sqlstr % params
+
+        assert conn.dialect.name == 'sqlite'
+
+        # params in positional order
+        pparams = (repr(params.get(name, None)) for name in compiled.positiontup) # type: ignore
+
+        sqlstr = re.sub(r'__\[POSTCOMPILE_([^]]*)\]', '?', sqlstr)
+        sqlstr = re.sub(r"\?", lambda m: next(pparams), sqlstr)
+
+        return sqlstr
+
+class HTMLLogger(BaseLogger):
+    """ Logger that formats messages in HTML.
+    """
+    def __init__(self) -> None:
+        self.buffer = io.StringIO()
+
+
+    def _timestamp(self) -> None:
+        self._write(f'<p class="timestamp">[{dt.datetime.now()}]</p>')
+
+
+    def get_buffer(self) -> str:
+        return HTML_HEADER + self.buffer.getvalue() + HTML_FOOTER
+
+
+    def function(self, func: str, **kwargs: Any) -> None:
+        self._timestamp()
+        self._write(f"<h1>Debug output for {func}()</h1>\n<p>Parameters:<dl>")
+        for name, value in kwargs.items():
+            self._write(f'<dt>{name}</dt><dd>{self._python_var(value)}</dd>')
+        self._write('</dl></p>')
+
+
+    def section(self, heading: str) -> None:
+        self._timestamp()
+        self._write(f"<h2>{heading}</h2>")
+
+
+    def comment(self, text: str) -> None:
+        self._timestamp()
+        self._write(f"<p>{text}</p>")
+
+
+    def var_dump(self, heading: str, var: Any) -> None:
+        self._timestamp()
+        if callable(var):
+            var = var()
+
+        self._write(f'<h5>{heading}</h5>{self._python_var(var)}')
+
+
+    def table_dump(self, heading: str, rows: Iterator[Optional[List[Any]]]) -> None:
+        self._timestamp()
+        head = next(rows)
+        assert head
+        self._write(f'<table><thead><tr><th colspan="{len(head)}">{heading}</th></tr><tr>')
+        for cell in head:
+            self._write(f'<th>{cell}</th>')
+        self._write('</tr></thead><tbody>')
+        for row in rows:
+            if row is not None:
+                self._write('<tr>')
+                for cell in row:
+                    self._write(f'<td>{cell}</td>')
+                self._write('</tr>')
+        self._write('</tbody></table>')
+
+
+    def result_dump(self, heading: str, results: Iterator[Tuple[Any, Any]]) -> None:
+        """ Print a list of search results generated by the generator function.
+        """
+        self._timestamp()
+        def format_osm(osm_object: Optional[Tuple[str, int]]) -> str:
+            if not osm_object:
+                return '-'
+
+            t, i = osm_object
+            if t == 'N':
+                fullt = 'node'
+            elif t == 'W':
+                fullt = 'way'
+            elif t == 'R':
+                fullt = 'relation'
+            else:
+                return f'{t}{i}'
+
+            return f'<a href="https://www.openstreetmap.org/{fullt}/{i}">{t}{i}</a>'
+
+        self._write(f'<h5>{heading}</h5><p><dl>')
+        total = 0
+        for rank, res in results:
+            self._write(f'<dt>[{rank:.3f}]</dt>  <dd>{res.source_table.name}(')
+            self._write(f"{_debug_name(res)}, type=({','.join(res.category)}), ")
+            self._write(f"rank={res.rank_address}, ")
+            self._write(f"osm={format_osm(res.osm_object)}, ")
+            self._write(f'cc={res.country_code}, ')
+            self._write(f'importance={res.importance or float("nan"):.5f})</dd>')
+            total += 1
+        self._write(f'</dl><b>TOTAL:</b> {total}</p>')
+
+
+    def sql(self, conn: AsyncConnection, statement: 'sa.Executable',
+            params: Union[Mapping[str, Any], Sequence[Mapping[str, Any]], None]) -> None:
+        self._timestamp()
+        sqlstr = self.format_sql(conn, statement, params)
+        if CODE_HIGHLIGHT:
+            sqlstr = highlight(sqlstr, PostgresLexer(),
+                               HtmlFormatter(nowrap=True, lineseparator='<br />'))
+            self._write(f'<div class="highlight"><code class="lang-sql">{sqlstr}</code></div>')
+        else:
+            self._write(f'<code class="lang-sql">{html.escape(sqlstr)}</code>')
+
+
+    def _python_var(self, var: Any) -> str:
+        if CODE_HIGHLIGHT:
+            fmt = highlight(str(var), PythonLexer(), HtmlFormatter(nowrap=True))
+            return f'<div class="highlight"><code class="lang-python">{fmt}</code></div>'
+
+        return f'<code class="lang-python">{html.escape(str(var))}</code>'
+
+
+    def _write(self, text: str) -> None:
+        """ Add the raw text to the debug output.
+        """
+        self.buffer.write(text)
+
+
+class TextLogger(BaseLogger):
+    """ Logger creating output suitable for the console.
+    """
+    def __init__(self) -> None:
+        self.buffer = io.StringIO()
+
+
+    def _timestamp(self) -> None:
+        self._write(f'[{dt.datetime.now()}]\n')
+
+
+    def get_buffer(self) -> str:
+        return self.buffer.getvalue()
+
+
+    def function(self, func: str, **kwargs: Any) -> None:
+        self._write(f"#### Debug output for {func}()\n\nParameters:\n")
+        for name, value in kwargs.items():
+            self._write(f'  {name}: {self._python_var(value)}\n')
+        self._write('\n')
+
+
+    def section(self, heading: str) -> None:
+        self._timestamp()
+        self._write(f"\n# {heading}\n\n")
+
+
+    def comment(self, text: str) -> None:
+        self._write(f"{text}\n")
+
+
+    def var_dump(self, heading: str, var: Any) -> None:
+        if callable(var):
+            var = var()
+
+        self._write(f'{heading}:\n  {self._python_var(var)}\n\n')
+
+
+    def table_dump(self, heading: str, rows: Iterator[Optional[List[Any]]]) -> None:
+        self._write(f'{heading}:\n')
+        data = [list(map(self._python_var, row)) if row else None for row in rows]
+        assert data[0] is not None
+        num_cols = len(data[0])
+
+        maxlens = [max(len(d[i]) for d in data if d) for i in range(num_cols)]
+        tablewidth = sum(maxlens) + 3 * num_cols + 1
+        row_format = '| ' +' | '.join(f'{{:<{l}}}' for l in maxlens) + ' |\n'
+        self._write('-'*tablewidth + '\n')
+        self._write(row_format.format(*data[0]))
+        self._write('-'*tablewidth + '\n')
+        for row in data[1:]:
+            if row:
+                self._write(row_format.format(*row))
+            else:
+                self._write('-'*tablewidth + '\n')
+        if data[-1]:
+            self._write('-'*tablewidth + '\n')
+
+
+    def result_dump(self, heading: str, results: Iterator[Tuple[Any, Any]]) -> None:
+        self._timestamp()
+        self._write(f'{heading}:\n')
+        total = 0
+        for rank, res in results:
+            self._write(f'[{rank:.3f}]  {res.source_table.name}(')
+            self._write(f"{_debug_name(res)}, type=({','.join(res.category)}), ")
+            self._write(f"rank={res.rank_address}, ")
+            self._write(f"osm={''.join(map(str, res.osm_object or []))}, ")
+            self._write(f'cc={res.country_code}, ')
+            self._write(f'importance={res.importance or -1:.5f})\n')
+            total += 1
+        self._write(f'TOTAL: {total}\n\n')
+
+
+    def sql(self, conn: AsyncConnection, statement: 'sa.Executable',
+            params: Union[Mapping[str, Any], Sequence[Mapping[str, Any]], None]) -> None:
+        self._timestamp()
+        sqlstr = '\n| '.join(textwrap.wrap(self.format_sql(conn, statement, params), width=78))
+        self._write(f"| {sqlstr}\n\n")
+
+
+    def _python_var(self, var: Any) -> str:
+        return str(var)
+
+
+    def _write(self, text: str) -> None:
+        self.buffer.write(text)
+
+
+logger: ContextVar[BaseLogger] = ContextVar('logger', default=BaseLogger())
+
+
+def set_log_output(fmt: str) -> None:
+    """ Enable collecting debug information.
+    """
+    if fmt == 'html':
+        logger.set(HTMLLogger())
+    elif fmt == 'text':
+        logger.set(TextLogger())
+    else:
+        logger.set(BaseLogger())
+
+
+def log() -> BaseLogger:
+    """ Return the logger for the current context.
+    """
+    return logger.get()
+
+
+def get_and_disable() -> str:
+    """ Return the current content of the debug buffer and disable logging.
+    """
+    buf = logger.get().get_buffer()
+    logger.set(BaseLogger())
+    return buf
+
+
+HTML_HEADER: str = """<!DOCTYPE html>
+<html>
+<head>
+  <title>Nominatim - Debug</title>
+  <style>
+""" + \
+(HtmlFormatter(nobackground=True).get_style_defs('.highlight') if CODE_HIGHLIGHT else '') +\
+"""
+    h2 { font-size: x-large }
+
+    dl {
+      padding-left: 10pt;
+      font-family: monospace
+    }
+
+    dt {
+      float: left;
+      font-weight: bold;
+      margin-right: 0.5em
+    }
+
+    dt::after { content: ": "; }
+
+    dd::after {
+      clear: left;
+      display: block
+    }
+
+    .lang-sql {
+      color: #555;
+      font-size: small
+    }
+
+    h5 {
+        border: solid lightgrey 0.1pt;
+        margin-bottom: 0;
+        background-color: #f7f7f7
+    }
+
+    h5 + .highlight {
+        padding: 3pt;
+        border: solid lightgrey 0.1pt
+    }
+
+    table, th, tbody {
+        border: thin solid;
+        border-collapse: collapse;
+    }
+    td {
+        border-right: thin solid;
+        padding-left: 3pt;
+        padding-right: 3pt;
+    }
+
+    .timestamp {
+        font-size: 0.8em;
+        color: darkblue;
+        width: calc(100% - 5pt);
+        text-align: right;
+        position: absolute;
+        left: 0;
+        margin-top: -5px;
+    }
+  </style>
+</head>
+<body>
+"""
+
+HTML_FOOTER: str = "</body></html>"

nominatim/api/lookup.py

@@ -0,0 +1,251 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Implementation of place lookup by ID.
+"""
+from typing import Optional, Callable, Tuple, Type
+import datetime as dt
+
+import sqlalchemy as sa
+
+from nominatim.typing import SaColumn, SaRow, SaSelect
+from nominatim.api.connection import SearchConnection
+import nominatim.api.types as ntyp
+import nominatim.api.results as nres
+from nominatim.api.logging import log
+
+RowFunc = Callable[[Optional[SaRow], Type[nres.BaseResultT]], Optional[nres.BaseResultT]]
+
+GeomFunc = Callable[[SaSelect, SaColumn], SaSelect]
+
+
+
+async def find_in_placex(conn: SearchConnection, place: ntyp.PlaceRef,
+                         add_geometries: GeomFunc) -> Optional[SaRow]:
+    """ Search for the given place in the placex table and return the
+        base information.
+    """
+    log().section("Find in placex table")
+    t = conn.t.placex
+    sql = sa.select(t.c.place_id, t.c.osm_type, t.c.osm_id, t.c.name,
+                    t.c.class_, t.c.type, t.c.admin_level,
+                    t.c.address, t.c.extratags,
+                    t.c.housenumber, t.c.postcode, t.c.country_code,
+                    t.c.importance, t.c.wikipedia, t.c.indexed_date,
+                    t.c.parent_place_id, t.c.rank_address, t.c.rank_search,
+                    t.c.linked_place_id,
+                    t.c.geometry.ST_Expand(0).label('bbox'),
+                    t.c.centroid)
+
+    if isinstance(place, ntyp.PlaceID):
+        sql = sql.where(t.c.place_id == place.place_id)
+    elif isinstance(place, ntyp.OsmID):
+        sql = sql.where(t.c.osm_type == place.osm_type)\
+                 .where(t.c.osm_id == place.osm_id)
+        if place.osm_class:
+            sql = sql.where(t.c.class_ == place.osm_class)
+        else:
+            sql = sql.order_by(t.c.class_)
+        sql = sql.limit(1)
+    else:
+        return None
+
+    return (await conn.execute(add_geometries(sql, t.c.geometry))).one_or_none()
+
+
+async def find_in_osmline(conn: SearchConnection, place: ntyp.PlaceRef,
+                          add_geometries: GeomFunc) -> Optional[SaRow]:
+    """ Search for the given place in the osmline table and return the
+        base information.
+    """
+    log().section("Find in interpolation table")
+    t = conn.t.osmline
+    sql = sa.select(t.c.place_id, t.c.osm_id, t.c.parent_place_id,
+                    t.c.indexed_date, t.c.startnumber, t.c.endnumber,
+                    t.c.step, t.c.address, t.c.postcode, t.c.country_code,
+                    t.c.linegeo.ST_Centroid().label('centroid'))
+
+    if isinstance(place, ntyp.PlaceID):
+        sql = sql.where(t.c.place_id == place.place_id)
+    elif isinstance(place, ntyp.OsmID) and place.osm_type == 'W':
+        # There may be multiple interpolations for a single way.
+        # If 'class' contains a number, return the one that belongs to that number.
+        sql = sql.where(t.c.osm_id == place.osm_id).limit(1)
+        if place.osm_class and place.osm_class.isdigit():
+            sql = sql.order_by(sa.func.greatest(0,
+                                                int(place.osm_class) - t.c.endnumber,
+                                                t.c.startnumber - int(place.osm_class)))
+    else:
+        return None
+
+    return (await conn.execute(add_geometries(sql, t.c.linegeo))).one_or_none()
+
+
+async def find_in_tiger(conn: SearchConnection, place: ntyp.PlaceRef,
+                        add_geometries: GeomFunc) -> Optional[SaRow]:
+    """ Search for the given place in the table of Tiger addresses and return
+        the base information. Only lookup by place ID is supported.
+    """
+    if not isinstance(place, ntyp.PlaceID):
+        return None
+
+    log().section("Find in TIGER table")
+    t = conn.t.tiger
+    parent = conn.t.placex
+    sql = sa.select(t.c.place_id, t.c.parent_place_id,
+                    parent.c.osm_type, parent.c.osm_id,
+                    t.c.startnumber, t.c.endnumber, t.c.step,
+                    t.c.postcode,
+                    t.c.linegeo.ST_Centroid().label('centroid'))\
+            .where(t.c.place_id == place.place_id)\
+            .join(parent, t.c.parent_place_id == parent.c.place_id, isouter=True)
+
+    return (await conn.execute(add_geometries(sql, t.c.linegeo))).one_or_none()
+
+
+async def find_in_postcode(conn: SearchConnection, place: ntyp.PlaceRef,
+                           add_geometries: GeomFunc) -> Optional[SaRow]:
+    """ Search for the given place in the postcode table and return the
+        base information. Only lookup by place ID is supported.
+    """
+    if not isinstance(place, ntyp.PlaceID):
+        return None
+
+    log().section("Find in postcode table")
+    t = conn.t.postcode
+    sql = sa.select(t.c.place_id, t.c.parent_place_id,
+                    t.c.rank_search, t.c.rank_address,
+                    t.c.indexed_date, t.c.postcode, t.c.country_code,
+                    t.c.geometry.label('centroid')) \
+            .where(t.c.place_id == place.place_id)
+
+    return (await conn.execute(add_geometries(sql, t.c.geometry))).one_or_none()
+
+
+async def find_in_all_tables(conn: SearchConnection, place: ntyp.PlaceRef,
+                             add_geometries: GeomFunc
+                            ) -> Tuple[Optional[SaRow], RowFunc[nres.BaseResultT]]:
+    """ Search for the given place in all data tables
+        and return the base information.
+    """
+    row = await find_in_placex(conn, place, add_geometries)
+    log().var_dump('Result (placex)', row)
+    if row is not None:
+        return row, nres.create_from_placex_row
+
+    row = await find_in_osmline(conn, place, add_geometries)
+    log().var_dump('Result (osmline)', row)
+    if row is not None:
+        return row, nres.create_from_osmline_row
+
+    row = await find_in_postcode(conn, place, add_geometries)
+    log().var_dump('Result (postcode)', row)
+    if row is not None:
+        return row, nres.create_from_postcode_row
+
+    row = await find_in_tiger(conn, place, add_geometries)
+    log().var_dump('Result (tiger)', row)
+    return row, nres.create_from_tiger_row
+
+
+async def get_detailed_place(conn: SearchConnection, place: ntyp.PlaceRef,
+                             details: ntyp.LookupDetails) -> Optional[nres.DetailedResult]:
+    """ Retrieve a place with additional details from the database.
+    """
+    log().function('get_detailed_place', place=place, details=details)
+
+    if details.geometry_output and details.geometry_output != ntyp.GeometryFormat.GEOJSON:
+        raise ValueError("lookup only supports geojosn polygon output.")
+
+    if details.geometry_output & ntyp.GeometryFormat.GEOJSON:
+        def _add_geometry(sql: SaSelect, column: SaColumn) -> SaSelect:
+            return sql.add_columns(sa.func.ST_AsGeoJSON(
+                                    sa.case((sa.func.ST_NPoints(column) > 5000,
+                                             sa.func.ST_SimplifyPreserveTopology(column, 0.0001)),
+                                            else_=column), 7).label('geometry_geojson'))
+    else:
+        def _add_geometry(sql: SaSelect, column: SaColumn) -> SaSelect:
+            return sql.add_columns(sa.func.ST_GeometryType(column).label('geometry_type'))
+
+    row_func: RowFunc[nres.DetailedResult]
+    row, row_func = await find_in_all_tables(conn, place, _add_geometry)
+
+    if row is None:
+        return None
+
+    result = row_func(row, nres.DetailedResult)
+    assert result is not None
+
+    # add missing details
+    assert result is not None
+    if 'type' in result.geometry:
+        result.geometry['type'] = GEOMETRY_TYPE_MAP.get(result.geometry['type'],
+                                                        result.geometry['type'])
+    indexed_date = getattr(row, 'indexed_date', None)
+    if indexed_date is not None:
+        result.indexed_date = indexed_date.replace(tzinfo=dt.timezone.utc)
+
+    await nres.add_result_details(conn, [result], details)
+
+    return result
+
+
+async def get_simple_place(conn: SearchConnection, place: ntyp.PlaceRef,
+                           details: ntyp.LookupDetails) -> Optional[nres.SearchResult]:
+    """ Retrieve a place as a simple search result from the database.
+    """
+    log().function('get_simple_place', place=place, details=details)
+
+    def _add_geometry(sql: SaSelect, col: SaColumn) -> SaSelect:
+        if not details.geometry_output:
+            return sql
+
+        out = []
+
+        if details.geometry_simplification > 0.0:
+            col = sa.func.ST_SimplifyPreserveTopology(col, details.geometry_simplification)
+
+        if details.geometry_output & ntyp.GeometryFormat.GEOJSON:
+            out.append(sa.func.ST_AsGeoJSON(col, 7).label('geometry_geojson'))
+        if details.geometry_output & ntyp.GeometryFormat.TEXT:
+            out.append(sa.func.ST_AsText(col).label('geometry_text'))
+        if details.geometry_output & ntyp.GeometryFormat.KML:
+            out.append(sa.func.ST_AsKML(col, 7).label('geometry_kml'))
+        if details.geometry_output & ntyp.GeometryFormat.SVG:
+            out.append(sa.func.ST_AsSVG(col, 0, 7).label('geometry_svg'))
+
+        return sql.add_columns(*out)
+
+
+    row_func: RowFunc[nres.SearchResult]
+    row, row_func = await find_in_all_tables(conn, place, _add_geometry)
+
+    if row is None:
+        return None
+
+    result = row_func(row, nres.SearchResult)
+    assert result is not None
+
+    # add missing details
+    assert result is not None
+    if hasattr(row, 'bbox'):
+        result.bbox = ntyp.Bbox.from_wkb(row.bbox)
+
+    await nres.add_result_details(conn, [result], details)
+
+    return result
+
+
+GEOMETRY_TYPE_MAP = {
+    'POINT': 'ST_Point',
+    'MULTIPOINT': 'ST_MultiPoint',
+    'LINESTRING': 'ST_LineString',
+    'MULTILINESTRING': 'ST_MultiLineString',
+    'POLYGON': 'ST_Polygon',
+    'MULTIPOLYGON': 'ST_MultiPolygon',
+    'GEOMETRYCOLLECTION': 'ST_GeometryCollection'
+}

nominatim/api/result_formatting.py

@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Helper classes and functions for formatting results into API responses.
+"""
+from typing import Type, TypeVar, Dict, List, Callable, Any, Mapping
+from collections import defaultdict
+
+T = TypeVar('T') # pylint: disable=invalid-name
+FormatFunc = Callable[[T, Mapping[str, Any]], str]
+
+
+class FormatDispatcher:
+    """ Helper class to conveniently create formatting functions in
+        a module using decorators.
+    """
+
+    def __init__(self) -> None:
+        self.format_functions: Dict[Type[Any], Dict[str, FormatFunc[Any]]] = defaultdict(dict)
+
+
+    def format_func(self, result_class: Type[T],
+                    fmt: str) -> Callable[[FormatFunc[T]], FormatFunc[T]]:
+        """ Decorator for a function that formats a given type of result into the
+            selected format.
+        """
+        def decorator(func: FormatFunc[T]) -> FormatFunc[T]:
+            self.format_functions[result_class][fmt] = func
+            return func
+
+        return decorator
+
+
+    def list_formats(self, result_type: Type[Any]) -> List[str]:
+        """ Return a list of formats supported by this formatter.
+        """
+        return list(self.format_functions[result_type].keys())
+
+
+    def supports_format(self, result_type: Type[Any], fmt: str) -> bool:
+        """ Check if the given format is supported by this formatter.
+        """
+        return fmt in self.format_functions[result_type]
+
+
+    def format_result(self, result: Any, fmt: str, options: Mapping[str, Any]) -> str:
+        """ Convert the given result into a string using the given format.
+
+            The format is expected to be in the list returned by
+            `list_formats()`.
+        """
+        return self.format_functions[type(result)][fmt](result, options)

nominatim/api/results.py

@@ -0,0 +1,752 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Dataclasses for search results and helper functions to fill them.
+
+Data classes are part of the public API while the functions are for
+internal use only. That's why they are implemented as free-standing functions
+instead of member functions.
+"""
+from typing import Optional, Tuple, Dict, Sequence, TypeVar, Type, List, cast, Callable
+import enum
+import dataclasses
+import datetime as dt
+
+import sqlalchemy as sa
+
+from nominatim.typing import SaSelect, SaRow
+from nominatim.db.sqlalchemy_types import Geometry
+from nominatim.api.types import Point, Bbox, LookupDetails
+from nominatim.api.connection import SearchConnection
+from nominatim.api.logging import log
+from nominatim.api.localization import Locales
+
+# This file defines complex result data classes.
+# pylint: disable=too-many-instance-attributes
+
+def _mingle_name_tags(names: Optional[Dict[str, str]]) -> Optional[Dict[str, str]]:
+    """ Mix-in names from linked places, so that they show up
+        as standard names where necessary.
+    """
+    if not names:
+        return None
+
+    out = {}
+    for k, v in names.items():
+        if k.startswith('_place_'):
+            outkey = k[7:]
+            out[k if outkey in names else outkey] = v
+        else:
+            out[k] = v
+
+    return out
+
+
+class SourceTable(enum.Enum):
+    """ The `SourceTable` type lists the possible sources a result can have.
+    """
+    PLACEX = 1
+    """ The placex table is the main source for result usually containing
+        OSM data.
+    """
+    OSMLINE = 2
+    """ The osmline table contains address interpolations from OSM data.
+        Interpolation addresses are always approximate. The OSM id in the
+        result refers to the OSM way with the interpolation line object.
+    """
+    TIGER = 3
+    """ TIGER address data contains US addresses imported on the side,
+        see [Installing TIGER data](../customize/Tiger.md).
+        TIGER address are also interpolations. The addresses always refer
+        to a street from OSM data. The OSM id in the result refers to
+        that street.
+    """
+    POSTCODE = 4
+    """ The postcode table contains artificial centroids for postcodes,
+        computed from the postcodes available with address points. Results
+        are always approximate.
+    """
+    COUNTRY = 5
+    """ The country table provides a fallback, when country data is missing
+        in the OSM data.
+    """
+
+
+@dataclasses.dataclass
+class AddressLine:
+    """ The `AddressLine` may contain the following fields about a related place
+        and its function as an address object. Most fields are optional.
+        Their presence depends on the kind and function of the address part.
+    """
+    category: Tuple[str, str]
+    """ Main category of the place, described by a key-value pair.
+    """
+    names: Dict[str, str]
+    """ All available names for the place including references, alternative
+        names and translations.
+    """
+    fromarea: bool
+    """ If true, then the exact area of the place is known. Without area
+        information, Nominatim has to make an educated guess if an address
+        belongs to one place or another.
+    """
+    isaddress: bool
+    """ If true, this place should be considered for the final address display.
+        Nominatim will sometimes include more than one candidate for
+        the address in the list when it cannot reliably determine where the
+        place belongs. It will consider names of all candidates when searching
+        but when displaying the result, only the most likely candidate should
+        be shown.
+    """
+    rank_address: int
+    """ [Address rank](../customize/Ranking.md#address-rank) of the place.
+    """
+    distance: float
+    """ Distance in degrees between the result place and this address part.
+    """
+    place_id: Optional[int] = None
+    """ Internal ID of the place.
+    """
+    osm_object: Optional[Tuple[str, int]] = None
+    """ OSM type and ID of the place, if such an object exists.
+    """
+    extratags: Optional[Dict[str, str]] = None
+    """ Any extra information available about the place. This is a dictionary
+        that usually contains OSM tag key-value pairs.
+    """
+
+    admin_level: Optional[int] = None
+    """ The administrative level of a boundary as tagged in the input data.
+        This field is only meaningful for places of the category
+        (boundary, administrative).
+    """
+
+    local_name: Optional[str] = None
+    """ Place holder for localization of this address part. See
+        [Localization](#localization) below.
+    """
+
+
+class AddressLines(List[AddressLine]):
+    """ Sequence of address lines order in descending order by their rank.
+    """
+
+    def localize(self, locales: Locales) -> List[str]:
+        """ Set the local name of address parts according to the chosen
+            locale. Return the list of local names without duplicates.
+
+            Only address parts that are marked as isaddress are localized
+            and returned.
+        """
+        label_parts: List[str] = []
+
+        for line in self:
+            if line.isaddress and line.names:
+                line.local_name = locales.display_name(line.names)
+                if not label_parts or label_parts[-1] != line.local_name:
+                    label_parts.append(line.local_name)
+
+        return label_parts
+
+
+
+@dataclasses.dataclass
+class WordInfo:
+    """ Each entry in the list of search terms contains the
+        following detailed information.
+    """
+    word_id: int
+    """ Internal identifier for the word.
+    """
+    word_token: str
+    """ Normalised and transliterated form of the word.
+        This form is used for searching.
+    """
+    word: Optional[str] = None
+    """ Untransliterated form, if available.
+    """
+
+
+WordInfos = Sequence[WordInfo]
+
+
+@dataclasses.dataclass
+class BaseResult:
+    """ Data class collecting information common to all
+        types of search results.
+    """
+    source_table: SourceTable
+    category: Tuple[str, str]
+    centroid: Point
+
+    place_id : Optional[int] = None
+    osm_object: Optional[Tuple[str, int]] = None
+    parent_place_id: Optional[int] = None
+    linked_place_id: Optional[int] = None
+    admin_level: int = 15
+
+    locale_name: Optional[str] = None
+    display_name: Optional[str] = None
+
+    names: Optional[Dict[str, str]] = None
+    address: Optional[Dict[str, str]] = None
+    extratags: Optional[Dict[str, str]] = None
+
+    housenumber: Optional[str] = None
+    postcode: Optional[str] = None
+    wikipedia: Optional[str] = None
+
+    rank_address: int = 30
+    rank_search: int = 30
+    importance: Optional[float] = None
+
+    country_code: Optional[str] = None
+
+    address_rows: Optional[AddressLines] = None
+    linked_rows: Optional[AddressLines] = None
+    parented_rows: Optional[AddressLines] = None
+    name_keywords: Optional[WordInfos] = None
+    address_keywords: Optional[WordInfos] = None
+
+    geometry: Dict[str, str] = dataclasses.field(default_factory=dict)
+
+    @property
+    def lat(self) -> float:
+        """ Get the latitude (or y) of the center point of the place.
+        """
+        return self.centroid[1]
+
+
+    @property
+    def lon(self) -> float:
+        """ Get the longitude (or x) of the center point of the place.
+        """
+        return self.centroid[0]
+
+
+    def calculated_importance(self) -> float:
+        """ Get a valid importance value. This is either the stored importance
+            of the value or an artificial value computed from the place's
+            search rank.
+        """
+        return self.importance or (0.40001 - (self.rank_search/75.0))
+
+
+    def localize(self, locales: Locales) -> None:
+        """ Fill the locale_name and the display_name field for the
+            place and, if available, its address information.
+        """
+        self.locale_name = locales.display_name(self.names)
+        if self.address_rows:
+            self.display_name = ', '.join(self.address_rows.localize(locales))
+        else:
+            self.display_name = self.locale_name
+
+
+
+BaseResultT = TypeVar('BaseResultT', bound=BaseResult)
+
+@dataclasses.dataclass
+class DetailedResult(BaseResult):
+    """ A search result with more internal information from the database
+        added.
+    """
+    indexed_date: Optional[dt.datetime] = None
+
+
+@dataclasses.dataclass
+class ReverseResult(BaseResult):
+    """ A search result for reverse geocoding.
+    """
+    distance: Optional[float] = None
+    bbox: Optional[Bbox] = None
+
+
+class ReverseResults(List[ReverseResult]):
+    """ Sequence of reverse lookup results ordered by distance.
+        May be empty when no result was found.
+    """
+
+
+@dataclasses.dataclass
+class SearchResult(BaseResult):
+    """ A search result for forward geocoding.
+    """
+    bbox: Optional[Bbox] = None
+    accuracy: float = 0.0
+
+
+    @property
+    def ranking(self) -> float:
+        """ Return the ranking, a combined measure of accuracy and importance.
+        """
+        return (self.accuracy if self.accuracy is not None else 1) \
+               - self.calculated_importance()
+
+
+class SearchResults(List[SearchResult]):
+    """ Sequence of forward lookup results ordered by relevance.
+        May be empty when no result was found.
+    """
+
+
+def _filter_geometries(row: SaRow) -> Dict[str, str]:
+    return {k[9:]: v for k, v in row._mapping.items() # pylint: disable=W0212
+            if k.startswith('geometry_')}
+
+
+def create_from_placex_row(row: Optional[SaRow],
+                           class_type: Type[BaseResultT]) -> Optional[BaseResultT]:
+    """ Construct a new result and add the data from the result row
+        from the placex table. 'class_type' defines the type of result
+        to return. Returns None if the row is None.
+    """
+    if row is None:
+        return None
+
+    return class_type(source_table=SourceTable.PLACEX,
+                      place_id=row.place_id,
+                      osm_object=(row.osm_type, row.osm_id),
+                      category=(row.class_, row.type),
+                      parent_place_id = row.parent_place_id,
+                      linked_place_id = getattr(row, 'linked_place_id', None),
+                      admin_level = getattr(row, 'admin_level', 15),
+                      names=_mingle_name_tags(row.name),
+                      address=row.address,
+                      extratags=row.extratags,
+                      housenumber=row.housenumber,
+                      postcode=row.postcode,
+                      wikipedia=row.wikipedia,
+                      rank_address=row.rank_address,
+                      rank_search=row.rank_search,
+                      importance=row.importance,
+                      country_code=row.country_code,
+                      centroid=Point.from_wkb(row.centroid),
+                      geometry=_filter_geometries(row))
+
+
+def create_from_osmline_row(row: Optional[SaRow],
+                            class_type: Type[BaseResultT]) -> Optional[BaseResultT]:
+    """ Construct a new result and add the data from the result row
+        from the address interpolation table osmline. 'class_type' defines
+        the type of result to return. Returns None if the row is None.
+
+        If the row contains a housenumber, then the housenumber is filled out.
+        Otherwise the result contains the interpolation information in extratags.
+    """
+    if row is None:
+        return None
+
+    hnr = getattr(row, 'housenumber', None)
+
+    res = class_type(source_table=SourceTable.OSMLINE,
+                     place_id=row.place_id,
+                     parent_place_id = row.parent_place_id,
+                     osm_object=('W', row.osm_id),
+                     category=('place', 'houses' if hnr is None else 'house'),
+                     address=row.address,
+                     postcode=row.postcode,
+                     country_code=row.country_code,
+                     centroid=Point.from_wkb(row.centroid),
+                     geometry=_filter_geometries(row))
+
+    if hnr is None:
+        res.extratags = {'startnumber': str(row.startnumber),
+                         'endnumber': str(row.endnumber),
+                         'step': str(row.step)}
+    else:
+        res.housenumber = str(hnr)
+
+    return res
+
+
+def create_from_tiger_row(row: Optional[SaRow],
+                          class_type: Type[BaseResultT],
+                          osm_type: Optional[str] = None,
+                          osm_id: Optional[int] = None) -> Optional[BaseResultT]:
+    """ Construct a new result and add the data from the result row
+        from the Tiger data interpolation table. 'class_type' defines
+        the type of result to return. Returns None if the row is None.
+
+        If the row contains a housenumber, then the housenumber is filled out.
+        Otherwise the result contains the interpolation information in extratags.
+    """
+    if row is None:
+        return None
+
+    hnr = getattr(row, 'housenumber', None)
+
+    res = class_type(source_table=SourceTable.TIGER,
+                     place_id=row.place_id,
+                     parent_place_id = row.parent_place_id,
+                     osm_object=(osm_type or row.osm_type, osm_id or row.osm_id),
+                     category=('place', 'houses' if hnr is None else 'house'),
+                     postcode=row.postcode,
+                     country_code='us',
+                     centroid=Point.from_wkb(row.centroid),
+                     geometry=_filter_geometries(row))
+
+    if hnr is None:
+        res.extratags = {'startnumber': str(row.startnumber),
+                         'endnumber': str(row.endnumber),
+                         'step': str(row.step)}
+    else:
+        res.housenumber = str(hnr)
+
+    return res
+
+
+def create_from_postcode_row(row: Optional[SaRow],
+                          class_type: Type[BaseResultT]) -> Optional[BaseResultT]:
+    """ Construct a new result and add the data from the result row
+        from the postcode table. 'class_type' defines
+        the type of result to return. Returns None if the row is None.
+    """
+    if row is None:
+        return None
+
+    return class_type(source_table=SourceTable.POSTCODE,
+                      place_id=row.place_id,
+                      parent_place_id = row.parent_place_id,
+                      category=('place', 'postcode'),
+                      names={'ref': row.postcode},
+                      rank_search=row.rank_search,
+                      rank_address=row.rank_address,
+                      country_code=row.country_code,
+                      centroid=Point.from_wkb(row.centroid),
+                      geometry=_filter_geometries(row))
+
+
+def create_from_country_row(row: Optional[SaRow],
+                        class_type: Type[BaseResultT]) -> Optional[BaseResultT]:
+    """ Construct a new result and add the data from the result row
+        from the fallback country tables. 'class_type' defines
+        the type of result to return. Returns None if the row is None.
+    """
+    if row is None:
+        return None
+
+    return class_type(source_table=SourceTable.COUNTRY,
+                      category=('place', 'country'),
+                      centroid=Point.from_wkb(row.centroid),
+                      names=row.name,
+                      rank_address=4, rank_search=4,
+                      country_code=row.country_code,
+                      geometry=_filter_geometries(row))
+
+
+async def add_result_details(conn: SearchConnection, results: List[BaseResultT],
+                             details: LookupDetails) -> None:
+    """ Retrieve more details from the database according to the
+        parameters specified in 'details'.
+    """
+    if results:
+        log().section('Query details for result')
+        if details.address_details:
+            log().comment('Query address details')
+            await complete_address_details(conn, results)
+        if details.linked_places:
+            log().comment('Query linked places')
+            for result in results:
+                await complete_linked_places(conn, result)
+        if details.parented_places:
+            log().comment('Query parent places')
+            for result in results:
+                await complete_parented_places(conn, result)
+        if details.keywords:
+            log().comment('Query keywords')
+            for result in results:
+                await complete_keywords(conn, result)
+        for result in results:
+            result.localize(details.locales)
+
+
+def _result_row_to_address_row(row: SaRow, isaddress: Optional[bool] = None) -> AddressLine:
+    """ Create a new AddressLine from the results of a database query.
+    """
+    extratags: Dict[str, str] = getattr(row, 'extratags', {}) or {}
+    if 'linked_place' in extratags:
+        extratags['place'] = extratags['linked_place']
+
+    names = _mingle_name_tags(row.name) or {}
+    if getattr(row, 'housenumber', None) is not None:
+        names['housenumber'] = row.housenumber
+
+    if isaddress is None:
+        isaddress = getattr(row, 'isaddress', True)
+
+    return AddressLine(place_id=row.place_id,
+                       osm_object=None if row.osm_type is None else (row.osm_type, row.osm_id),
+                       category=(getattr(row, 'class'), row.type),
+                       names=names,
+                       extratags=extratags,
+                       admin_level=row.admin_level,
+                       fromarea=row.fromarea,
+                       isaddress=isaddress,
+                       rank_address=row.rank_address,
+                       distance=row.distance)
+
+
+def _get_address_lookup_id(result: BaseResultT) -> int:
+    assert result.place_id
+    if result.source_table != SourceTable.PLACEX or result.rank_search > 27:
+        return result.parent_place_id or result.place_id
+
+    return result.linked_place_id or result.place_id
+
+
+async def _finalize_entry(conn: SearchConnection, result: BaseResultT) -> None:
+    assert result.address_rows is not None
+    if result.category[0] not in ('boundary', 'place')\
+       or result.category[1] not in ('postal_code', 'postcode'):
+        postcode = result.postcode
+        if not postcode and result.address:
+            postcode = result.address.get('postcode')
+        if postcode and ',' not in postcode and ';' not in postcode:
+            result.address_rows.append(AddressLine(
+                category=('place', 'postcode'),
+                names={'ref': postcode},
+                fromarea=False, isaddress=True, rank_address=5,
+                distance=0.0))
+    if result.country_code:
+        async def _get_country_names() -> Optional[Dict[str, str]]:
+            t = conn.t.country_name
+            sql = sa.select(t.c.name, t.c.derived_name)\
+                    .where(t.c.country_code == result.country_code)
+            for cres in await conn.execute(sql):
+                names = cast(Dict[str, str], cres[0])
+                if cres[1]:
+                    names.update(cast(Dict[str, str], cres[1]))
+                return names
+            return None
+
+        country_names = await conn.get_cached_value('COUNTRY_NAME',
+                                                    result.country_code,
+                                                    _get_country_names)
+        if country_names:
+            result.address_rows.append(AddressLine(
+                category=('place', 'country'),
+                names=country_names,
+                fromarea=False, isaddress=True, rank_address=4,
+                distance=0.0))
+        result.address_rows.append(AddressLine(
+            category=('place', 'country_code'),
+            names={'ref': result.country_code}, extratags = {},
+            fromarea=True, isaddress=False, rank_address=4,
+            distance=0.0))
+
+
+def _setup_address_details(result: BaseResultT) -> None:
+    """ Retrieve information about places that make up the address of the result.
+    """
+    result.address_rows = AddressLines()
+    if result.names:
+        result.address_rows.append(AddressLine(
+            place_id=result.place_id,
+            osm_object=result.osm_object,
+            category=result.category,
+            names=result.names,
+            extratags=result.extratags or {},
+            admin_level=result.admin_level,
+            fromarea=True, isaddress=True,
+            rank_address=result.rank_address, distance=0.0))
+    if result.source_table == SourceTable.PLACEX and result.address:
+        housenumber = result.address.get('housenumber')\
+                      or result.address.get('streetnumber')\
+                      or result.address.get('conscriptionnumber')
+    elif result.housenumber:
+        housenumber = result.housenumber
+    else:
+        housenumber = None
+    if housenumber:
+        result.address_rows.append(AddressLine(
+            category=('place', 'house_number'),
+            names={'ref': housenumber},
+            fromarea=True, isaddress=True, rank_address=28, distance=0))
+    if result.address and '_unlisted_place' in result.address:
+        result.address_rows.append(AddressLine(
+            category=('place', 'locality'),
+            names={'name': result.address['_unlisted_place']},
+            fromarea=False, isaddress=True, rank_address=25, distance=0))
+
+
+async def complete_address_details(conn: SearchConnection, results: List[BaseResultT]) -> None:
+    """ Retrieve information about places that make up the address of the result.
+    """
+    for result in results:
+        _setup_address_details(result)
+
+    ### Lookup entries from place_address line
+
+    lookup_ids = [{'pid': r.place_id,
+                   'lid': _get_address_lookup_id(r),
+                   'names': list(r.address.values()) if r.address else [],
+                   'c': ('SRID=4326;' + r.centroid.to_wkt()) if r.centroid else '' }
+                  for r in results if r.place_id]
+
+    if not lookup_ids:
+        return
+
+    ltab = sa.func.JsonArrayEach(sa.type_coerce(lookup_ids, sa.JSON))\
+             .table_valued(sa.column('value', type_=sa.JSON))
+
+    t = conn.t.placex
+    taddr = conn.t.addressline
+
+    sql = sa.select(ltab.c.value['pid'].as_integer().label('src_place_id'),
+                    t.c.place_id, t.c.osm_type, t.c.osm_id, t.c.name,
+                    t.c.class_, t.c.type, t.c.extratags,
+                    t.c.admin_level, taddr.c.fromarea,
+                    sa.case((t.c.rank_address == 11, 5),
+                            else_=t.c.rank_address).label('rank_address'),
+                    taddr.c.distance, t.c.country_code, t.c.postcode)\
+            .join(taddr, sa.or_(taddr.c.place_id == ltab.c.value['pid'].as_integer(),
+                                taddr.c.place_id == ltab.c.value['lid'].as_integer()))\
+            .join(t, taddr.c.address_place_id == t.c.place_id)\
+            .order_by('src_place_id')\
+            .order_by(sa.column('rank_address').desc())\
+            .order_by((taddr.c.place_id == ltab.c.value['pid'].as_integer()).desc())\
+            .order_by(sa.case((sa.func.CrosscheckNames(t.c.name, ltab.c.value['names']), 2),
+                              (taddr.c.isaddress, 0),
+                              (sa.and_(taddr.c.fromarea,
+                                       t.c.geometry.ST_Contains(
+                                           sa.func.ST_GeomFromEWKT(
+                                               ltab.c.value['c'].as_string()))), 1),
+                              else_=-1).desc())\
+            .order_by(taddr.c.fromarea.desc())\
+            .order_by(taddr.c.distance.desc())\
+            .order_by(t.c.rank_search.desc())
+
+
+    current_result = None
+    current_rank_address = -1
+    for row in await conn.execute(sql):
+        if current_result is None or row.src_place_id != current_result.place_id:
+            current_result = next((r for r in results if r.place_id == row.src_place_id), None)
+            assert current_result is not None
+            current_rank_address = -1
+
+        location_isaddress = row.rank_address != current_rank_address
+
+        if current_result.country_code is None and row.country_code:
+            current_result.country_code = row.country_code
+
+        if row.type in ('postcode', 'postal_code') and location_isaddress:
+            if not row.fromarea or \
+               (current_result.address and 'postcode' in current_result.address):
+                location_isaddress = False
+            else:
+                current_result.postcode = None
+
+        assert current_result.address_rows is not None
+        current_result.address_rows.append(_result_row_to_address_row(row, location_isaddress))
+        current_rank_address = row.rank_address
+
+    for result in results:
+        await _finalize_entry(conn, result)
+
+
+    ### Finally add the record for the parent entry where necessary.
+
+    parent_lookup_ids = list(filter(lambda e: e['pid'] != e['lid'], lookup_ids))
+    if parent_lookup_ids:
+        ltab = sa.func.JsonArrayEach(sa.type_coerce(parent_lookup_ids, sa.JSON))\
+                 .table_valued(sa.column('value', type_=sa.JSON))
+        sql = sa.select(ltab.c.value['pid'].as_integer().label('src_place_id'),
+                        t.c.place_id, t.c.osm_type, t.c.osm_id, t.c.name,
+                        t.c.class_, t.c.type, t.c.extratags,
+                        t.c.admin_level,
+                        t.c.rank_address)\
+                 .where(t.c.place_id == ltab.c.value['lid'].as_integer())
+
+        for row in await conn.execute(sql):
+            current_result = next((r for r in results if r.place_id == row.src_place_id), None)
+            assert current_result is not None
+            assert current_result.address_rows is not None
+
+            current_result.address_rows.append(AddressLine(
+                    place_id=row.place_id,
+                    osm_object=(row.osm_type, row.osm_id),
+                    category=(row.class_, row.type),
+                    names=row.name, extratags=row.extratags or {},
+                    admin_level=row.admin_level,
+                    fromarea=True, isaddress=True,
+                    rank_address=row.rank_address, distance=0.0))
+
+    ### Now sort everything
+    def mk_sort_key(place_id: Optional[int]) -> Callable[[AddressLine], Tuple[bool, int, bool]]:
+        return lambda a: (a.place_id != place_id, -a.rank_address, a.isaddress)
+
+    for result in results:
+        assert result.address_rows is not None
+        result.address_rows.sort(key=mk_sort_key(result.place_id))
+
+
+def _placex_select_address_row(conn: SearchConnection,
+                               centroid: Point) -> SaSelect:
+    t = conn.t.placex
+    return sa.select(t.c.place_id, t.c.osm_type, t.c.osm_id, t.c.name,
+                     t.c.class_.label('class'), t.c.type,
+                     t.c.admin_level, t.c.housenumber,
+                     t.c.geometry.is_area().label('fromarea'),
+                     t.c.rank_address,
+                     t.c.geometry.distance_spheroid(
+                       sa.bindparam('centroid', value=centroid, type_=Geometry)).label('distance'))
+
+
+async def complete_linked_places(conn: SearchConnection, result: BaseResult) -> None:
+    """ Retrieve information about places that link to the result.
+    """
+    result.linked_rows = AddressLines()
+    if result.source_table != SourceTable.PLACEX:
+        return
+
+    sql = _placex_select_address_row(conn, result.centroid)\
+            .where(conn.t.placex.c.linked_place_id == result.place_id)
+
+    for row in await conn.execute(sql):
+        result.linked_rows.append(_result_row_to_address_row(row))
+
+
+async def complete_keywords(conn: SearchConnection, result: BaseResult) -> None:
+    """ Retrieve information about the search terms used for this place.
+
+        Requires that the query analyzer was initialised to get access to
+        the word table.
+    """
+    t = conn.t.search_name
+    sql = sa.select(t.c.name_vector, t.c.nameaddress_vector)\
+            .where(t.c.place_id == result.place_id)
+
+    result.name_keywords = []
+    result.address_keywords = []
+
+    t = conn.t.meta.tables['word']
+    sel = sa.select(t.c.word_id, t.c.word_token, t.c.word)
+
+    for name_tokens, address_tokens in await conn.execute(sql):
+        for row in await conn.execute(sel.where(t.c.word_id.in_(name_tokens))):
+            result.name_keywords.append(WordInfo(*row))
+
+        for row in await conn.execute(sel.where(t.c.word_id.in_(address_tokens))):
+            result.address_keywords.append(WordInfo(*row))
+
+
+async def complete_parented_places(conn: SearchConnection, result: BaseResult) -> None:
+    """ Retrieve information about places that the result provides the
+        address for.
+    """
+    result.parented_rows = AddressLines()
+    if result.source_table != SourceTable.PLACEX:
+        return
+
+    sql = _placex_select_address_row(conn, result.centroid)\
+            .where(conn.t.placex.c.parent_place_id == result.place_id)\
+            .where(conn.t.placex.c.rank_search == 30)
+
+    for row in await conn.execute(sql):
+        result.parented_rows.append(_result_row_to_address_row(row))

nominatim/api/reverse.py

@@ -0,0 +1,590 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Implementation of reverse geocoding.
+"""
+from typing import Optional, List, Callable, Type, Tuple, Dict, Any, cast, Union
+import functools
+
+import sqlalchemy as sa
+
+from nominatim.typing import SaColumn, SaSelect, SaFromClause, SaLabel, SaRow,\
+                             SaBind, SaLambdaSelect
+from nominatim.api.connection import SearchConnection
+import nominatim.api.results as nres
+from nominatim.api.logging import log
+from nominatim.api.types import AnyPoint, DataLayer, ReverseDetails, GeometryFormat, Bbox
+from nominatim.db.sqlalchemy_types import Geometry
+
+# In SQLAlchemy expression which compare with NULL need to be expressed with
+# the equal sign.
+# pylint: disable=singleton-comparison
+
+RowFunc = Callable[[Optional[SaRow], Type[nres.ReverseResult]], Optional[nres.ReverseResult]]
+
+WKT_PARAM: SaBind = sa.bindparam('wkt', type_=Geometry)
+MAX_RANK_PARAM: SaBind = sa.bindparam('max_rank')
+
+def no_index(expr: SaColumn) -> SaColumn:
+    """ Wrap the given expression, so that the query planner will
+        refrain from using the expression for index lookup.
+    """
+    return sa.func.coalesce(sa.null(), expr) # pylint: disable=not-callable
+
+
+def _select_from_placex(t: SaFromClause, use_wkt: bool = True) -> SaSelect:
+    """ Create a select statement with the columns relevant for reverse
+        results.
+    """
+    if not use_wkt:
+        distance = t.c.distance
+        centroid = t.c.centroid
+    else:
+        distance = t.c.geometry.ST_Distance(WKT_PARAM)
+        centroid = sa.case((t.c.geometry.is_line_like(), t.c.geometry.ST_ClosestPoint(WKT_PARAM)),
+                           else_=t.c.centroid).label('centroid')
+
+
+    return sa.select(t.c.place_id, t.c.osm_type, t.c.osm_id, t.c.name,
+                     t.c.class_, t.c.type,
+                     t.c.address, t.c.extratags,
+                     t.c.housenumber, t.c.postcode, t.c.country_code,
+                     t.c.importance, t.c.wikipedia,
+                     t.c.parent_place_id, t.c.rank_address, t.c.rank_search,
+                     centroid,
+                     t.c.linked_place_id, t.c.admin_level,
+                     distance.label('distance'),
+                     t.c.geometry.ST_Expand(0).label('bbox'))
+
+
+def _interpolated_housenumber(table: SaFromClause) -> SaLabel:
+    return sa.cast(table.c.startnumber
+                    + sa.func.round(((table.c.endnumber - table.c.startnumber) * table.c.position)
+                                    / table.c.step) * table.c.step,
+                   sa.Integer).label('housenumber')
+
+
+def _interpolated_position(table: SaFromClause) -> SaLabel:
+    fac = sa.cast(table.c.step, sa.Float) / (table.c.endnumber - table.c.startnumber)
+    rounded_pos = sa.func.round(table.c.position / fac) * fac
+    return sa.case(
+             (table.c.endnumber == table.c.startnumber, table.c.linegeo.ST_Centroid()),
+              else_=table.c.linegeo.ST_LineInterpolatePoint(rounded_pos)).label('centroid')
+
+
+def _locate_interpolation(table: SaFromClause) -> SaLabel:
+    """ Given a position, locate the closest point on the line.
+    """
+    return sa.case((table.c.linegeo.is_line_like(),
+                    table.c.linegeo.ST_LineLocatePoint(WKT_PARAM)),
+                   else_=0).label('position')
+
+
+def _get_closest(*rows: Optional[SaRow]) -> Optional[SaRow]:
+    return min(rows, key=lambda row: 1000 if row is None else row.distance)
+
+
+class ReverseGeocoder:
+    """ Class implementing the logic for looking up a place from a
+        coordinate.
+    """
+
+    def __init__(self, conn: SearchConnection, params: ReverseDetails,
+                 restrict_to_country_areas: bool = False) -> None:
+        self.conn = conn
+        self.params = params
+        self.restrict_to_country_areas = restrict_to_country_areas
+
+        self.bind_params: Dict[str, Any] = {'max_rank': params.max_rank}
+
+
+    @property
+    def max_rank(self) -> int:
+        """ Return the maximum configured rank.
+        """
+        return self.params.max_rank
+
+
+    def has_geometries(self) -> bool:
+        """ Check if any geometries are requested.
+        """
+        return bool(self.params.geometry_output)
+
+
+    def layer_enabled(self, *layer: DataLayer) -> bool:
+        """ Return true when any of the given layer types are requested.
+        """
+        return any(self.params.layers & l for l in layer)
+
+
+    def layer_disabled(self, *layer: DataLayer) -> bool:
+        """ Return true when none of the given layer types is requested.
+        """
+        return not any(self.params.layers & l for l in layer)
+
+
+    def has_feature_layers(self) -> bool:
+        """ Return true if any layer other than ADDRESS or POI is requested.
+        """
+        return self.layer_enabled(DataLayer.RAILWAY, DataLayer.MANMADE, DataLayer.NATURAL)
+
+
+    def _add_geometry_columns(self, sql: SaLambdaSelect, col: SaColumn) -> SaSelect:
+        out = []
+
+        if self.params.geometry_simplification > 0.0:
+            col = sa.func.ST_SimplifyPreserveTopology(col, self.params.geometry_simplification)
+
+        if self.params.geometry_output & GeometryFormat.GEOJSON:
+            out.append(sa.func.ST_AsGeoJSON(col, 7).label('geometry_geojson'))
+        if self.params.geometry_output & GeometryFormat.TEXT:
+            out.append(sa.func.ST_AsText(col).label('geometry_text'))
+        if self.params.geometry_output & GeometryFormat.KML:
+            out.append(sa.func.ST_AsKML(col, 7).label('geometry_kml'))
+        if self.params.geometry_output & GeometryFormat.SVG:
+            out.append(sa.func.ST_AsSVG(col, 0, 7).label('geometry_svg'))
+
+        return sql.add_columns(*out)
+
+
+    def _filter_by_layer(self, table: SaFromClause) -> SaColumn:
+        if self.layer_enabled(DataLayer.MANMADE):
+            exclude = []
+            if self.layer_disabled(DataLayer.RAILWAY):
+                exclude.append('railway')
+            if self.layer_disabled(DataLayer.NATURAL):
+                exclude.extend(('natural', 'water', 'waterway'))
+            return table.c.class_.not_in(tuple(exclude))
+
+        include = []
+        if self.layer_enabled(DataLayer.RAILWAY):
+            include.append('railway')
+        if self.layer_enabled(DataLayer.NATURAL):
+            include.extend(('natural', 'water', 'waterway'))
+        return table.c.class_.in_(tuple(include))
+
+
+    async def _find_closest_street_or_poi(self, distance: float) -> Optional[SaRow]:
+        """ Look up the closest rank 26+ place in the database, which
+            is closer than the given distance.
+        """
+        t = self.conn.t.placex
+
+        # PostgreSQL must not get the distance as a parameter because
+        # there is a danger it won't be able to properly estimate index use
+        # when used with prepared statements
+        diststr = sa.text(f"{distance}")
+
+        sql: SaLambdaSelect = sa.lambda_stmt(lambda: _select_from_placex(t)
+                .where(t.c.geometry.within_distance(WKT_PARAM, diststr))
+                .where(t.c.indexed_status == 0)
+                .where(t.c.linked_place_id == None)
+                .where(sa.or_(sa.not_(t.c.geometry.is_area()),
+                              t.c.centroid.ST_Distance(WKT_PARAM) < diststr))
+                .order_by('distance')
+                .limit(1))
+
+        if self.has_geometries():
+            sql = self._add_geometry_columns(sql, t.c.geometry)
+
+        restrict: List[Union[SaColumn, Callable[[], SaColumn]]] = []
+
+        if self.layer_enabled(DataLayer.ADDRESS):
+            max_rank = min(29, self.max_rank)
+            restrict.append(lambda: no_index(t.c.rank_address).between(26, max_rank))
+            if self.max_rank == 30:
+                restrict.append(lambda: sa.func.IsAddressPoint(t))
+        if self.layer_enabled(DataLayer.POI) and self.max_rank == 30:
+            restrict.append(lambda: sa.and_(no_index(t.c.rank_search) == 30,
+                                            t.c.class_.not_in(('place', 'building')),
+                                            sa.not_(t.c.geometry.is_line_like())))
+        if self.has_feature_layers():
+            restrict.append(sa.and_(no_index(t.c.rank_search).between(26, MAX_RANK_PARAM),
+                                    no_index(t.c.rank_address) == 0,
+                                    self._filter_by_layer(t)))
+
+        if not restrict:
+            return None
+
+        sql = sql.where(sa.or_(*restrict))
+
+        return (await self.conn.execute(sql, self.bind_params)).one_or_none()
+
+
+    async def _find_housenumber_for_street(self, parent_place_id: int) -> Optional[SaRow]:
+        t = self.conn.t.placex
+
+        def _base_query() -> SaSelect:
+            return _select_from_placex(t)\
+                .where(t.c.geometry.within_distance(WKT_PARAM, 0.001))\
+                .where(t.c.parent_place_id == parent_place_id)\
+                .where(sa.func.IsAddressPoint(t))\
+                .where(t.c.indexed_status == 0)\
+                .where(t.c.linked_place_id == None)\
+                .order_by('distance')\
+                .limit(1)
+
+        sql: SaLambdaSelect
+        if self.has_geometries():
+            sql = self._add_geometry_columns(_base_query(), t.c.geometry)
+        else:
+            sql = sa.lambda_stmt(_base_query)
+
+        return (await self.conn.execute(sql, self.bind_params)).one_or_none()
+
+
+    async def _find_interpolation_for_street(self, parent_place_id: Optional[int],
+                                             distance: float) -> Optional[SaRow]:
+        t = self.conn.t.osmline
+
+        sql = sa.select(t,
+                        t.c.linegeo.ST_Distance(WKT_PARAM).label('distance'),
+                        _locate_interpolation(t))\
+                .where(t.c.linegeo.within_distance(WKT_PARAM, distance))\
+                .where(t.c.startnumber != None)\
+                .order_by('distance')\
+                .limit(1)
+
+        if parent_place_id is not None:
+            sql = sql.where(t.c.parent_place_id == parent_place_id)
+
+        inner = sql.subquery('ipol')
+
+        sql = sa.select(inner.c.place_id, inner.c.osm_id,
+                             inner.c.parent_place_id, inner.c.address,
+                             _interpolated_housenumber(inner),
+                             _interpolated_position(inner),
+                             inner.c.postcode, inner.c.country_code,
+                             inner.c.distance)
+
+        if self.has_geometries():
+            sub = sql.subquery('geom')
+            sql = self._add_geometry_columns(sa.select(sub), sub.c.centroid)
+
+        return (await self.conn.execute(sql, self.bind_params)).one_or_none()
+
+
+    async def _find_tiger_number_for_street(self, parent_place_id: int) -> Optional[SaRow]:
+        t = self.conn.t.tiger
+
+        def _base_query() -> SaSelect:
+            inner = sa.select(t,
+                              t.c.linegeo.ST_Distance(WKT_PARAM).label('distance'),
+                              _locate_interpolation(t))\
+                      .where(t.c.linegeo.within_distance(WKT_PARAM, 0.001))\
+                      .where(t.c.parent_place_id == parent_place_id)\
+                      .order_by('distance')\
+                      .limit(1)\
+                      .subquery('tiger')
+
+            return sa.select(inner.c.place_id,
+                             inner.c.parent_place_id,
+                             _interpolated_housenumber(inner),
+                             _interpolated_position(inner),
+                             inner.c.postcode,
+                             inner.c.distance)
+
+        sql: SaLambdaSelect
+        if self.has_geometries():
+            sub = _base_query().subquery('geom')
+            sql = self._add_geometry_columns(sa.select(sub), sub.c.centroid)
+        else:
+            sql = sa.lambda_stmt(_base_query)
+
+        return (await self.conn.execute(sql, self.bind_params)).one_or_none()
+
+
+    async def lookup_street_poi(self) -> Tuple[Optional[SaRow], RowFunc]:
+        """ Find a street or POI/address for the given WKT point.
+        """
+        log().section('Reverse lookup on street/address level')
+        distance = 0.006
+        parent_place_id = None
+
+        row = await self._find_closest_street_or_poi(distance)
+        row_func: RowFunc = nres.create_from_placex_row
+        log().var_dump('Result (street/building)', row)
+
+        # If the closest result was a street, but an address was requested,
+        # check for a housenumber nearby which is part of the street.
+        if row is not None:
+            if self.max_rank > 27 \
+               and self.layer_enabled(DataLayer.ADDRESS) \
+               and row.rank_address <= 27:
+                distance = 0.001
+                parent_place_id = row.place_id
+                log().comment('Find housenumber for street')
+                addr_row = await self._find_housenumber_for_street(parent_place_id)
+                log().var_dump('Result (street housenumber)', addr_row)
+
+                if addr_row is not None:
+                    row = addr_row
+                    row_func = nres.create_from_placex_row
+                    distance = addr_row.distance
+                elif row.country_code == 'us' and parent_place_id is not None:
+                    log().comment('Find TIGER housenumber for street')
+                    addr_row = await self._find_tiger_number_for_street(parent_place_id)
+                    log().var_dump('Result (street Tiger housenumber)', addr_row)
+
+                    if addr_row is not None:
+                        row_func = cast(RowFunc,
+                                        functools.partial(nres.create_from_tiger_row,
+                                                          osm_type=row.osm_type,
+                                                          osm_id=row.osm_id))
+                        row = addr_row
+            else:
+                distance = row.distance
+
+        # Check for an interpolation that is either closer than our result
+        # or belongs to a close street found.
+        if self.max_rank > 27 and self.layer_enabled(DataLayer.ADDRESS):
+            log().comment('Find interpolation for street')
+            addr_row = await self._find_interpolation_for_street(parent_place_id,
+                                                                 distance)
+            log().var_dump('Result (street interpolation)', addr_row)
+            if addr_row is not None:
+                row = addr_row
+                row_func = nres.create_from_osmline_row
+
+        return row, row_func
+
+
+    async def _lookup_area_address(self) -> Optional[SaRow]:
+        """ Lookup large addressable areas for the given WKT point.
+        """
+        log().comment('Reverse lookup by larger address area features')
+        t = self.conn.t.placex
+
+        def _base_query() -> SaSelect:
+            # The inner SQL brings results in the right order, so that
+            # later only a minimum of results needs to be checked with ST_Contains.
+            inner = sa.select(t, sa.literal(0.0).label('distance'))\
+                      .where(t.c.rank_search.between(5, MAX_RANK_PARAM))\
+                      .where(t.c.geometry.intersects(WKT_PARAM))\
+                      .where(sa.func.PlacexGeometryReverseLookuppolygon())\
+                      .order_by(sa.desc(t.c.rank_search))\
+                      .limit(50)\
+                      .subquery('area')
+
+            return _select_from_placex(inner, False)\
+                      .where(inner.c.geometry.ST_Contains(WKT_PARAM))\
+                      .order_by(sa.desc(inner.c.rank_search))\
+                      .limit(1)
+
+        sql: SaLambdaSelect = sa.lambda_stmt(_base_query)
+        if self.has_geometries():
+            sql = self._add_geometry_columns(sql, sa.literal_column('area.geometry'))
+
+        address_row = (await self.conn.execute(sql, self.bind_params)).one_or_none()
+        log().var_dump('Result (area)', address_row)
+
+        if address_row is not None and address_row.rank_search < self.max_rank:
+            log().comment('Search for better matching place nodes inside the area')
+
+            address_rank = address_row.rank_search
+            address_id = address_row.place_id
+
+            def _place_inside_area_query() -> SaSelect:
+                inner = \
+                    sa.select(t,
+                              t.c.geometry.ST_Distance(WKT_PARAM).label('distance'))\
+                      .where(t.c.rank_search > address_rank)\
+                      .where(t.c.rank_search <= MAX_RANK_PARAM)\
+                      .where(t.c.indexed_status == 0)\
+                      .where(sa.func.IntersectsReverseDistance(t, WKT_PARAM))\
+                      .order_by(sa.desc(t.c.rank_search))\
+                      .limit(50)\
+                      .subquery('places')
+
+                touter = t.alias('outer')
+                return _select_from_placex(inner, False)\
+                    .join(touter, touter.c.geometry.ST_Contains(inner.c.geometry))\
+                    .where(touter.c.place_id == address_id)\
+                    .where(sa.func.IsBelowReverseDistance(inner.c.distance, inner.c.rank_search))\
+                    .order_by(sa.desc(inner.c.rank_search), inner.c.distance)\
+                    .limit(1)
+
+            if self.has_geometries():
+                sql = self._add_geometry_columns(_place_inside_area_query(),
+                                                 sa.literal_column('places.geometry'))
+            else:
+                sql = sa.lambda_stmt(_place_inside_area_query)
+
+            place_address_row = (await self.conn.execute(sql, self.bind_params)).one_or_none()
+            log().var_dump('Result (place node)', place_address_row)
+
+            if place_address_row is not None:
+                return place_address_row
+
+        return address_row
+
+
+    async def _lookup_area_others(self) -> Optional[SaRow]:
+        t = self.conn.t.placex
+
+        inner = sa.select(t, t.c.geometry.ST_Distance(WKT_PARAM).label('distance'))\
+                  .where(t.c.rank_address == 0)\
+                  .where(t.c.rank_search.between(5, MAX_RANK_PARAM))\
+                  .where(t.c.name != None)\
+                  .where(t.c.indexed_status == 0)\
+                  .where(t.c.linked_place_id == None)\
+                  .where(self._filter_by_layer(t))\
+                  .where(t.c.geometry.intersects(sa.func.ST_Expand(WKT_PARAM, 0.007)))\
+                  .order_by(sa.desc(t.c.rank_search))\
+                  .order_by('distance')\
+                  .limit(50)\
+                  .subquery()
+
+        sql = _select_from_placex(inner, False)\
+                  .where(sa.or_(sa.not_(inner.c.geometry.is_area()),
+                                inner.c.geometry.ST_Contains(WKT_PARAM)))\
+                  .order_by(sa.desc(inner.c.rank_search), inner.c.distance)\
+                  .limit(1)
+
+        if self.has_geometries():
+            sql = self._add_geometry_columns(sql, inner.c.geometry)
+
+        row = (await self.conn.execute(sql, self.bind_params)).one_or_none()
+        log().var_dump('Result (non-address feature)', row)
+
+        return row
+
+
+    async def lookup_area(self) -> Optional[SaRow]:
+        """ Lookup large areas for the current search.
+        """
+        log().section('Reverse lookup by larger area features')
+
+        if self.layer_enabled(DataLayer.ADDRESS):
+            address_row = await self._lookup_area_address()
+        else:
+            address_row = None
+
+        if self.has_feature_layers():
+            other_row = await self._lookup_area_others()
+        else:
+            other_row = None
+
+        return _get_closest(address_row, other_row)
+
+
+    async def lookup_country_codes(self) -> List[str]:
+        """ Lookup the country for the current search.
+        """
+        log().section('Reverse lookup by country code')
+        t = self.conn.t.country_grid
+        sql = sa.select(t.c.country_code).distinct()\
+                .where(t.c.geometry.ST_Contains(WKT_PARAM))
+
+        ccodes = [cast(str, r[0]) for r in await self.conn.execute(sql, self.bind_params)]
+        log().var_dump('Country codes', ccodes)
+        return ccodes
+
+
+    async def lookup_country(self, ccodes: List[str]) -> Optional[SaRow]:
+        """ Lookup the country for the current search.
+        """
+        if not ccodes:
+            ccodes = await self.lookup_country_codes()
+
+        if not ccodes:
+            return None
+
+        t = self.conn.t.placex
+        if self.max_rank > 4:
+            log().comment('Search for place nodes in country')
+
+            def _base_query() -> SaSelect:
+                inner = \
+                    sa.select(t,
+                              t.c.geometry.ST_Distance(WKT_PARAM).label('distance'))\
+                      .where(t.c.rank_search > 4)\
+                      .where(t.c.rank_search <= MAX_RANK_PARAM)\
+                      .where(t.c.indexed_status == 0)\
+                      .where(t.c.country_code.in_(ccodes))\
+                      .where(sa.func.IntersectsReverseDistance(t, WKT_PARAM))\
+                      .order_by(sa.desc(t.c.rank_search))\
+                      .limit(50)\
+                      .subquery('area')
+
+                return _select_from_placex(inner, False)\
+                    .where(sa.func.IsBelowReverseDistance(inner.c.distance, inner.c.rank_search))\
+                    .order_by(sa.desc(inner.c.rank_search), inner.c.distance)\
+                    .limit(1)
+
+            sql: SaLambdaSelect
+            if self.has_geometries():
+                sql = self._add_geometry_columns(_base_query(),
+                                                 sa.literal_column('area.geometry'))
+            else:
+                sql = sa.lambda_stmt(_base_query)
+
+            address_row = (await self.conn.execute(sql, self.bind_params)).one_or_none()
+            log().var_dump('Result (addressable place node)', address_row)
+        else:
+            address_row = None
+
+        if address_row is None:
+            # Still nothing, then return a country with the appropriate country code.
+            def _country_base_query() -> SaSelect:
+                return _select_from_placex(t)\
+                         .where(t.c.country_code.in_(ccodes))\
+                         .where(t.c.rank_address == 4)\
+                         .where(t.c.rank_search == 4)\
+                         .where(t.c.linked_place_id == None)\
+                         .order_by('distance')\
+                         .limit(1)
+
+            if self.has_geometries():
+                sql = self._add_geometry_columns(_country_base_query(), t.c.geometry)
+            else:
+                sql = sa.lambda_stmt(_country_base_query)
+
+            address_row = (await self.conn.execute(sql, self.bind_params)).one_or_none()
+
+        return address_row
+
+
+    async def lookup(self, coord: AnyPoint) -> Optional[nres.ReverseResult]:
+        """ Look up a single coordinate. Returns the place information,
+            if a place was found near the coordinates or None otherwise.
+        """
+        log().function('reverse_lookup', coord=coord, params=self.params)
+
+
+        self.bind_params['wkt'] = f'POINT({coord[0]} {coord[1]})'
+
+        row: Optional[SaRow] = None
+        row_func: RowFunc = nres.create_from_placex_row
+
+        if self.max_rank >= 26:
+            row, tmp_row_func = await self.lookup_street_poi()
+            if row is not None:
+                row_func = tmp_row_func
+
+        if row is None:
+            if self.restrict_to_country_areas:
+                ccodes = await self.lookup_country_codes()
+                if not ccodes:
+                    return None
+            else:
+                ccodes = []
+
+            if self.max_rank > 4:
+                row = await self.lookup_area()
+            if row is None and self.layer_enabled(DataLayer.ADDRESS):
+                row = await self.lookup_country(ccodes)
+
+        result = row_func(row, nres.ReverseResult)
+        if result is not None:
+            assert row is not None
+            result.distance = row.distance
+            if hasattr(row, 'bbox'):
+                result.bbox = Bbox.from_wkb(row.bbox)
+            await nres.add_result_details(self.conn, [result], self.params)
+
+        return result

nominatim/api/search/__init__.py

@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Module for forward search.
+"""
+# pylint: disable=useless-import-alias
+
+from .geocoder import (ForwardGeocoder as ForwardGeocoder)
+from .query import (Phrase as Phrase,
+                    PhraseType as PhraseType)
+from .query_analyzer_factory import (make_query_analyzer as make_query_analyzer)

nominatim/api/search/db_search_builder.py

@@ -0,0 +1,411 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Conversion from token assignment to an abstract DB search.
+"""
+from typing import Optional, List, Tuple, Iterator, Dict
+import heapq
+
+from nominatim.api.types import SearchDetails, DataLayer
+from nominatim.api.search.query import QueryStruct, Token, TokenType, TokenRange, BreakType
+from nominatim.api.search.token_assignment import TokenAssignment
+import nominatim.api.search.db_search_fields as dbf
+import nominatim.api.search.db_searches as dbs
+import nominatim.api.search.db_search_lookups as lookups
+
+
+def wrap_near_search(categories: List[Tuple[str, str]],
+                     search: dbs.AbstractSearch) -> dbs.NearSearch:
+    """ Create a new search that wraps the given search in a search
+        for near places of the given category.
+    """
+    return dbs.NearSearch(penalty=search.penalty,
+                          categories=dbf.WeightedCategories(categories,
+                                                            [0.0] * len(categories)),
+                          search=search)
+
+
+def build_poi_search(category: List[Tuple[str, str]],
+                     countries: Optional[List[str]]) -> dbs.PoiSearch:
+    """ Create a new search for places by the given category, possibly
+        constraint to the given countries.
+    """
+    if countries:
+        ccs = dbf.WeightedStrings(countries, [0.0] * len(countries))
+    else:
+        ccs = dbf.WeightedStrings([], [])
+
+    class _PoiData(dbf.SearchData):
+        penalty = 0.0
+        qualifiers = dbf.WeightedCategories(category, [0.0] * len(category))
+        countries=ccs
+
+    return dbs.PoiSearch(_PoiData())
+
+
+class SearchBuilder:
+    """ Build the abstract search queries from token assignments.
+    """
+
+    def __init__(self, query: QueryStruct, details: SearchDetails) -> None:
+        self.query = query
+        self.details = details
+
+
+    @property
+    def configured_for_country(self) -> bool:
+        """ Return true if the search details are configured to
+            allow countries in the result.
+        """
+        return self.details.min_rank <= 4 and self.details.max_rank >= 4 \
+               and self.details.layer_enabled(DataLayer.ADDRESS)
+
+
+    @property
+    def configured_for_postcode(self) -> bool:
+        """ Return true if the search details are configured to
+            allow postcodes in the result.
+        """
+        return self.details.min_rank <= 5 and self.details.max_rank >= 11\
+               and self.details.layer_enabled(DataLayer.ADDRESS)
+
+
+    @property
+    def configured_for_housenumbers(self) -> bool:
+        """ Return true if the search details are configured to
+            allow addresses in the result.
+        """
+        return self.details.max_rank >= 30 \
+               and self.details.layer_enabled(DataLayer.ADDRESS)
+
+
+    def build(self, assignment: TokenAssignment) -> Iterator[dbs.AbstractSearch]:
+        """ Yield all possible abstract searches for the given token assignment.
+        """
+        sdata = self.get_search_data(assignment)
+        if sdata is None:
+            return
+
+        near_items = self.get_near_items(assignment)
+        if near_items is not None and not near_items:
+            return # impossible compbination of near items and category parameter
+
+        if assignment.name is None:
+            if near_items and not sdata.postcodes:
+                sdata.qualifiers = near_items
+                near_items = None
+                builder = self.build_poi_search(sdata)
+            elif assignment.housenumber:
+                hnr_tokens = self.query.get_tokens(assignment.housenumber,
+                                                   TokenType.HOUSENUMBER)
+                builder = self.build_housenumber_search(sdata, hnr_tokens, assignment.address)
+            else:
+                builder = self.build_special_search(sdata, assignment.address,
+                                                    bool(near_items))
+        else:
+            builder = self.build_name_search(sdata, assignment.name, assignment.address,
+                                             bool(near_items))
+
+        if near_items:
+            penalty = min(near_items.penalties)
+            near_items.penalties = [p - penalty for p in near_items.penalties]
+            for search in builder:
+                search_penalty = search.penalty
+                search.penalty = 0.0
+                yield dbs.NearSearch(penalty + assignment.penalty + search_penalty,
+                                     near_items, search)
+        else:
+            for search in builder:
+                search.penalty += assignment.penalty
+                yield search
+
+
+    def build_poi_search(self, sdata: dbf.SearchData) -> Iterator[dbs.AbstractSearch]:
+        """ Build abstract search query for a simple category search.
+            This kind of search requires an additional geographic constraint.
+        """
+        if not sdata.housenumbers \
+           and ((self.details.viewbox and self.details.bounded_viewbox) or self.details.near):
+            yield dbs.PoiSearch(sdata)
+
+
+    def build_special_search(self, sdata: dbf.SearchData,
+                             address: List[TokenRange],
+                             is_category: bool) -> Iterator[dbs.AbstractSearch]:
+        """ Build abstract search queries for searches that do not involve
+            a named place.
+        """
+        if sdata.qualifiers:
+            # No special searches over qualifiers supported.
+            return
+
+        if sdata.countries and not address and not sdata.postcodes \
+           and self.configured_for_country:
+            yield dbs.CountrySearch(sdata)
+
+        if sdata.postcodes and (is_category or self.configured_for_postcode):
+            penalty = 0.0 if sdata.countries else 0.1
+            if address:
+                sdata.lookups = [dbf.FieldLookup('nameaddress_vector',
+                                                 [t.token for r in address
+                                                  for t in self.query.get_partials_list(r)],
+                                                 lookups.Restrict)]
+                penalty += 0.2
+            yield dbs.PostcodeSearch(penalty, sdata)
+
+
+    def build_housenumber_search(self, sdata: dbf.SearchData, hnrs: List[Token],
+                                 address: List[TokenRange]) -> Iterator[dbs.AbstractSearch]:
+        """ Build a simple address search for special entries where the
+            housenumber is the main name token.
+        """
+        sdata.lookups = [dbf.FieldLookup('name_vector', [t.token for t in hnrs], lookups.LookupAny)]
+        expected_count = sum(t.count for t in hnrs)
+
+        partials = {t.token: t.count for trange in address
+                       for t in self.query.get_partials_list(trange)}
+
+        if expected_count < 8000:
+            sdata.lookups.append(dbf.FieldLookup('nameaddress_vector',
+                                                 list(partials), lookups.Restrict))
+        elif len(partials) != 1 or list(partials.values())[0] < 10000:
+            sdata.lookups.append(dbf.FieldLookup('nameaddress_vector',
+                                                 list(partials), lookups.LookupAll))
+        else:
+            addr_fulls = [t.token for t
+                          in self.query.get_tokens(address[0], TokenType.WORD)]
+            if len(addr_fulls) > 5:
+                return
+            sdata.lookups.append(
+                dbf.FieldLookup('nameaddress_vector', addr_fulls, lookups.LookupAny))
+
+        sdata.housenumbers = dbf.WeightedStrings([], [])
+        yield dbs.PlaceSearch(0.05, sdata, expected_count)
+
+
+    def build_name_search(self, sdata: dbf.SearchData,
+                          name: TokenRange, address: List[TokenRange],
+                          is_category: bool) -> Iterator[dbs.AbstractSearch]:
+        """ Build abstract search queries for simple name or address searches.
+        """
+        if is_category or not sdata.housenumbers or self.configured_for_housenumbers:
+            ranking = self.get_name_ranking(name)
+            name_penalty = ranking.normalize_penalty()
+            if ranking.rankings:
+                sdata.rankings.append(ranking)
+            for penalty, count, lookup in self.yield_lookups(name, address):
+                sdata.lookups = lookup
+                yield dbs.PlaceSearch(penalty + name_penalty, sdata, count)
+
+
+    def yield_lookups(self, name: TokenRange, address: List[TokenRange])\
+                          -> Iterator[Tuple[float, int, List[dbf.FieldLookup]]]:
+        """ Yield all variants how the given name and address should best
+            be searched for. This takes into account how frequent the terms
+            are and tries to find a lookup that optimizes index use.
+        """
+        penalty = 0.0 # extra penalty
+        name_partials = {t.token: t for t in self.query.get_partials_list(name)}
+
+        addr_partials = [t for r in address for t in self.query.get_partials_list(r)]
+        addr_tokens = list({t.token for t in addr_partials})
+
+        partials_indexed = all(t.is_indexed for t in name_partials.values()) \
+                           and all(t.is_indexed for t in addr_partials)
+        exp_count = min(t.count for t in name_partials.values()) / (2**(len(name_partials) - 1))
+
+        if (len(name_partials) > 3 or exp_count < 8000) and partials_indexed:
+            yield penalty, exp_count, dbf.lookup_by_names(list(name_partials.keys()), addr_tokens)
+            return
+
+        # Partial term to frequent. Try looking up by rare full names first.
+        name_fulls = self.query.get_tokens(name, TokenType.WORD)
+        if name_fulls:
+            fulls_count = sum(t.count for t in name_fulls)
+            # At this point drop unindexed partials from the address.
+            # This might yield wrong results, nothing we can do about that.
+            if not partials_indexed:
+                addr_tokens = [t.token for t in addr_partials if t.is_indexed]
+                penalty += 1.2 * sum(t.penalty for t in addr_partials if not t.is_indexed)
+            # Any of the full names applies with all of the partials from the address
+            yield penalty, fulls_count / (2**len(addr_tokens)),\
+                  dbf.lookup_by_any_name([t.token for t in name_fulls],
+                                         addr_tokens,
+                                         fulls_count > 30000 / max(1, len(addr_tokens)))
+
+        # To catch remaining results, lookup by name and address
+        # We only do this if there is a reasonable number of results expected.
+        exp_count = exp_count / (2**len(addr_tokens)) if addr_tokens else exp_count
+        if exp_count < 10000 and all(t.is_indexed for t in name_partials.values()):
+            lookup = [dbf.FieldLookup('name_vector', list(name_partials.keys()), lookups.LookupAll)]
+            if addr_tokens:
+                lookup.append(dbf.FieldLookup('nameaddress_vector', addr_tokens, lookups.LookupAll))
+            penalty += 0.35 * max(1 if name_fulls else 0.1,
+                                  5 - len(name_partials) - len(addr_tokens))
+            yield penalty, exp_count, lookup
+
+
+    def get_name_ranking(self, trange: TokenRange,
+                         db_field: str = 'name_vector') -> dbf.FieldRanking:
+        """ Create a ranking expression for a name term in the given range.
+        """
+        name_fulls = self.query.get_tokens(trange, TokenType.WORD)
+        ranks = [dbf.RankedTokens(t.penalty, [t.token]) for t in name_fulls]
+        ranks.sort(key=lambda r: r.penalty)
+        # Fallback, sum of penalty for partials
+        name_partials = self.query.get_partials_list(trange)
+        default = sum(t.penalty for t in name_partials) + 0.2
+        return dbf.FieldRanking(db_field, default, ranks)
+
+
+    def get_addr_ranking(self, trange: TokenRange) -> dbf.FieldRanking:
+        """ Create a list of ranking expressions for an address term
+            for the given ranges.
+        """
+        todo: List[Tuple[int, int, dbf.RankedTokens]] = []
+        heapq.heappush(todo, (0, trange.start, dbf.RankedTokens(0.0, [])))
+        ranks: List[dbf.RankedTokens] = []
+
+        while todo: # pylint: disable=too-many-nested-blocks
+            neglen, pos, rank = heapq.heappop(todo)
+            for tlist in self.query.nodes[pos].starting:
+                if tlist.ttype in (TokenType.PARTIAL, TokenType.WORD):
+                    if tlist.end < trange.end:
+                        chgpenalty = PENALTY_WORDCHANGE[self.query.nodes[tlist.end].btype]
+                        if tlist.ttype == TokenType.PARTIAL:
+                            penalty = rank.penalty + chgpenalty \
+                                      + max(t.penalty for t in tlist.tokens)
+                            heapq.heappush(todo, (neglen - 1, tlist.end,
+                                                  dbf.RankedTokens(penalty, rank.tokens)))
+                        else:
+                            for t in tlist.tokens:
+                                heapq.heappush(todo, (neglen - 1, tlist.end,
+                                                      rank.with_token(t, chgpenalty)))
+                    elif tlist.end == trange.end:
+                        if tlist.ttype == TokenType.PARTIAL:
+                            ranks.append(dbf.RankedTokens(rank.penalty
+                                                          + max(t.penalty for t in tlist.tokens),
+                                                          rank.tokens))
+                        else:
+                            ranks.extend(rank.with_token(t, 0.0) for t in tlist.tokens)
+                        if len(ranks) >= 10:
+                            # Too many variants, bail out and only add
+                            # Worst-case Fallback: sum of penalty of partials
+                            name_partials = self.query.get_partials_list(trange)
+                            default = sum(t.penalty for t in name_partials) + 0.2
+                            ranks.append(dbf.RankedTokens(rank.penalty + default, []))
+                            # Bail out of outer loop
+                            todo.clear()
+                            break
+
+        ranks.sort(key=lambda r: len(r.tokens))
+        default = ranks[0].penalty + 0.3
+        del ranks[0]
+        ranks.sort(key=lambda r: r.penalty)
+
+        return dbf.FieldRanking('nameaddress_vector', default, ranks)
+
+
+    def get_search_data(self, assignment: TokenAssignment) -> Optional[dbf.SearchData]:
+        """ Collect the tokens for the non-name search fields in the
+            assignment.
+        """
+        sdata = dbf.SearchData()
+        sdata.penalty = assignment.penalty
+        if assignment.country:
+            tokens = self.get_country_tokens(assignment.country)
+            if not tokens:
+                return None
+            sdata.set_strings('countries', tokens)
+        elif self.details.countries:
+            sdata.countries = dbf.WeightedStrings(self.details.countries,
+                                                  [0.0] * len(self.details.countries))
+        if assignment.housenumber:
+            sdata.set_strings('housenumbers',
+                              self.query.get_tokens(assignment.housenumber,
+                                                    TokenType.HOUSENUMBER))
+        if assignment.postcode:
+            sdata.set_strings('postcodes',
+                              self.query.get_tokens(assignment.postcode,
+                                                    TokenType.POSTCODE))
+        if assignment.qualifier:
+            tokens = self.get_qualifier_tokens(assignment.qualifier)
+            if not tokens:
+                return None
+            sdata.set_qualifiers(tokens)
+        elif self.details.categories:
+            sdata.qualifiers = dbf.WeightedCategories(self.details.categories,
+                                                      [0.0] * len(self.details.categories))
+
+        if assignment.address:
+            if not assignment.name and assignment.housenumber:
+                # housenumber search: the first item needs to be handled like
+                # a name in ranking or penalties are not comparable with
+                # normal searches.
+                sdata.set_ranking([self.get_name_ranking(assignment.address[0],
+                                                         db_field='nameaddress_vector')]
+                                  + [self.get_addr_ranking(r) for r in assignment.address[1:]])
+            else:
+                sdata.set_ranking([self.get_addr_ranking(r) for r in assignment.address])
+        else:
+            sdata.rankings = []
+
+        return sdata
+
+
+    def get_country_tokens(self, trange: TokenRange) -> List[Token]:
+        """ Return the list of country tokens for the given range,
+            optionally filtered by the country list from the details
+            parameters.
+        """
+        tokens = self.query.get_tokens(trange, TokenType.COUNTRY)
+        if self.details.countries:
+            tokens = [t for t in tokens if t.lookup_word in self.details.countries]
+
+        return tokens
+
+
+    def get_qualifier_tokens(self, trange: TokenRange) -> List[Token]:
+        """ Return the list of qualifier tokens for the given range,
+            optionally filtered by the qualifier list from the details
+            parameters.
+        """
+        tokens = self.query.get_tokens(trange, TokenType.QUALIFIER)
+        if self.details.categories:
+            tokens = [t for t in tokens if t.get_category() in self.details.categories]
+
+        return tokens
+
+
+    def get_near_items(self, assignment: TokenAssignment) -> Optional[dbf.WeightedCategories]:
+        """ Collect tokens for near items search or use the categories
+            requested per parameter.
+            Returns None if no category search is requested.
+        """
+        if assignment.near_item:
+            tokens: Dict[Tuple[str, str], float] = {}
+            for t in self.query.get_tokens(assignment.near_item, TokenType.NEAR_ITEM):
+                cat = t.get_category()
+                # The category of a near search will be that of near_item.
+                # Thus, if search is restricted to a category parameter,
+                # the two sets must intersect.
+                if (not self.details.categories or cat in self.details.categories)\
+                   and t.penalty < tokens.get(cat, 1000.0):
+                    tokens[cat] = t.penalty
+            return dbf.WeightedCategories(list(tokens.keys()), list(tokens.values()))
+
+        return None
+
+
+PENALTY_WORDCHANGE = {
+    BreakType.START: 0.0,
+    BreakType.END: 0.0,
+    BreakType.PHRASE: 0.0,
+    BreakType.WORD: 0.1,
+    BreakType.PART: 0.2,
+    BreakType.TOKEN: 0.4
+}

nominatim/api/search/db_search_fields.py

@@ -0,0 +1,253 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Data structures for more complex fields in abstract search descriptions.
+"""
+from typing import List, Tuple, Iterator, Dict, Type
+import dataclasses
+
+import sqlalchemy as sa
+
+from nominatim.typing import SaFromClause, SaColumn, SaExpression
+from nominatim.api.search.query import Token
+import nominatim.api.search.db_search_lookups as lookups
+from nominatim.utils.json_writer import JsonWriter
+
+
+@dataclasses.dataclass
+class WeightedStrings:
+    """ A list of strings together with a penalty.
+    """
+    values: List[str]
+    penalties: List[float]
+
+    def __bool__(self) -> bool:
+        return bool(self.values)
+
+
+    def __iter__(self) -> Iterator[Tuple[str, float]]:
+        return iter(zip(self.values, self.penalties))
+
+
+    def get_penalty(self, value: str, default: float = 1000.0) -> float:
+        """ Get the penalty for the given value. Returns the given default
+            if the value does not exist.
+        """
+        try:
+            return self.penalties[self.values.index(value)]
+        except ValueError:
+            pass
+        return default
+
+
+@dataclasses.dataclass
+class WeightedCategories:
+    """ A list of class/type tuples together with a penalty.
+    """
+    values: List[Tuple[str, str]]
+    penalties: List[float]
+
+    def __bool__(self) -> bool:
+        return bool(self.values)
+
+
+    def __iter__(self) -> Iterator[Tuple[Tuple[str, str], float]]:
+        return iter(zip(self.values, self.penalties))
+
+
+    def get_penalty(self, value: Tuple[str, str], default: float = 1000.0) -> float:
+        """ Get the penalty for the given value. Returns the given default
+            if the value does not exist.
+        """
+        try:
+            return self.penalties[self.values.index(value)]
+        except ValueError:
+            pass
+        return default
+
+
+    def sql_restrict(self, table: SaFromClause) -> SaExpression:
+        """ Return an SQLAlcheny expression that restricts the
+            class and type columns of the given table to the values
+            in the list.
+            Must not be used with an empty list.
+        """
+        assert self.values
+        if len(self.values) == 1:
+            return sa.and_(table.c.class_ == self.values[0][0],
+                           table.c.type == self.values[0][1])
+
+        return sa.or_(*(sa.and_(table.c.class_ == c, table.c.type == t)
+                        for c, t in self.values))
+
+
+@dataclasses.dataclass(order=True)
+class RankedTokens:
+    """ List of tokens together with the penalty of using it.
+    """
+    penalty: float
+    tokens: List[int]
+
+    def with_token(self, t: Token, transition_penalty: float) -> 'RankedTokens':
+        """ Create a new RankedTokens list with the given token appended.
+            The tokens penalty as well as the given transition penalty
+            are added to the overall penalty.
+        """
+        return RankedTokens(self.penalty + t.penalty + transition_penalty,
+                            self.tokens + [t.token])
+
+
+@dataclasses.dataclass
+class FieldRanking:
+    """ A list of rankings to be applied sequentially until one matches.
+        The matched ranking determines the penalty. If none matches a
+        default penalty is applied.
+    """
+    column: str
+    default: float
+    rankings: List[RankedTokens]
+
+    def normalize_penalty(self) -> float:
+        """ Reduce the default and ranking penalties, such that the minimum
+            penalty is 0. Return the penalty that was subtracted.
+        """
+        if self.rankings:
+            min_penalty = min(self.default, min(r.penalty for r in self.rankings))
+        else:
+            min_penalty = self.default
+        if min_penalty > 0.0:
+            self.default -= min_penalty
+            for ranking in self.rankings:
+                ranking.penalty -= min_penalty
+        return min_penalty
+
+
+    def sql_penalty(self, table: SaFromClause) -> SaColumn:
+        """ Create an SQL expression for the rankings.
+        """
+        assert self.rankings
+
+        rout = JsonWriter().start_array()
+        for rank in self.rankings:
+            rout.start_array().value(rank.penalty).next()
+            rout.start_array()
+            for token in rank.tokens:
+                rout.value(token).next()
+            rout.end_array()
+            rout.end_array().next()
+        rout.end_array()
+
+        return sa.func.weigh_search(table.c[self.column], rout(), self.default)
+
+
+@dataclasses.dataclass
+class FieldLookup:
+    """ A list of tokens to be searched for. The column names the database
+        column to search in and the lookup_type the operator that is applied.
+        'lookup_all' requires all tokens to match. 'lookup_any' requires
+        one of the tokens to match. 'restrict' requires to match all tokens
+        but avoids the use of indexes.
+    """
+    column: str
+    tokens: List[int]
+    lookup_type: Type[lookups.LookupType]
+
+    def sql_condition(self, table: SaFromClause) -> SaColumn:
+        """ Create an SQL expression for the given match condition.
+        """
+        return self.lookup_type(table, self.column, self.tokens)
+
+
+class SearchData:
+    """ Search fields derived from query and token assignment
+        to be used with the SQL queries.
+    """
+    penalty: float
+
+    lookups: List[FieldLookup] = []
+    rankings: List[FieldRanking]
+
+    housenumbers: WeightedStrings = WeightedStrings([], [])
+    postcodes: WeightedStrings = WeightedStrings([], [])
+    countries: WeightedStrings = WeightedStrings([], [])
+
+    qualifiers: WeightedCategories = WeightedCategories([], [])
+
+
+    def set_strings(self, field: str, tokens: List[Token]) -> None:
+        """ Set on of the WeightedStrings properties from the given
+            token list. Adapt the global penalty, so that the
+            minimum penalty is 0.
+        """
+        if tokens:
+            min_penalty = min(t.penalty for t in tokens)
+            self.penalty += min_penalty
+            wstrs = WeightedStrings([t.lookup_word for t in tokens],
+                                    [t.penalty - min_penalty for t in tokens])
+
+            setattr(self, field, wstrs)
+
+
+    def set_qualifiers(self, tokens: List[Token]) -> None:
+        """ Set the qulaifier field from the given tokens.
+        """
+        if tokens:
+            categories: Dict[Tuple[str, str], float] = {}
+            min_penalty = 1000.0
+            for t in tokens:
+                min_penalty = min(min_penalty, t.penalty)
+                cat = t.get_category()
+                if t.penalty < categories.get(cat, 1000.0):
+                    categories[cat] = t.penalty
+            self.penalty += min_penalty
+            self.qualifiers = WeightedCategories(list(categories.keys()),
+                                                 list(categories.values()))
+
+
+    def set_ranking(self, rankings: List[FieldRanking]) -> None:
+        """ Set the list of rankings and normalize the ranking.
+        """
+        self.rankings = []
+        for ranking in rankings:
+            if ranking.rankings:
+                self.penalty += ranking.normalize_penalty()
+                self.rankings.append(ranking)
+            else:
+                self.penalty += ranking.default
+
+
+def lookup_by_names(name_tokens: List[int], addr_tokens: List[int]) -> List[FieldLookup]:
+    """ Create a lookup list where name tokens are looked up via index
+        and potential address tokens are used to restrict the search further.
+    """
+    lookup = [FieldLookup('name_vector', name_tokens, lookups.LookupAll)]
+    if addr_tokens:
+        lookup.append(FieldLookup('nameaddress_vector', addr_tokens, lookups.Restrict))
+
+    return lookup
+
+
+def lookup_by_any_name(name_tokens: List[int], addr_tokens: List[int],
+                       use_index_for_addr: bool) -> List[FieldLookup]:
+    """ Create a lookup list where name tokens are looked up via index
+        and only one of the name tokens must be present.
+        Potential address tokens are used to restrict the search further.
+    """
+    lookup = [FieldLookup('name_vector', name_tokens, lookups.LookupAny)]
+    if addr_tokens:
+        lookup.append(FieldLookup('nameaddress_vector', addr_tokens,
+                                  lookups.LookupAll if use_index_for_addr else lookups.Restrict))
+
+    return lookup
+
+
+def lookup_by_addr(name_tokens: List[int], addr_tokens: List[int]) -> List[FieldLookup]:
+    """ Create a lookup list where address tokens are looked up via index
+        and the name tokens are only used to restrict the search further.
+    """
+    return [FieldLookup('name_vector', name_tokens, lookups.Restrict),
+            FieldLookup('nameaddress_vector', addr_tokens, lookups.LookupAll)]

nominatim/api/search/db_search_lookups.py

@@ -0,0 +1,114 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Implementation of lookup functions for the search_name table.
+"""
+from typing import List, Any
+
+import sqlalchemy as sa
+from sqlalchemy.ext.compiler import compiles
+
+from nominatim.typing import SaFromClause
+from nominatim.db.sqlalchemy_types import IntArray
+
+# pylint: disable=consider-using-f-string
+
+LookupType = sa.sql.expression.FunctionElement[Any]
+
+class LookupAll(LookupType):
+    """ Find all entries in search_name table that contain all of
+        a given list of tokens using an index for the search.
+    """
+    inherit_cache = True
+
+    def __init__(self, table: SaFromClause, column: str, tokens: List[int]) -> None:
+        super().__init__(table.c.place_id, getattr(table.c, column), column,
+                         sa.type_coerce(tokens, IntArray))
+
+
+@compiles(LookupAll) # type: ignore[no-untyped-call, misc]
+def _default_lookup_all(element: LookupAll,
+                        compiler: 'sa.Compiled', **kw: Any) -> str:
+    _, col, _, tokens = list(element.clauses)
+    return "(%s @> %s)" % (compiler.process(col, **kw),
+                           compiler.process(tokens, **kw))
+
+
+@compiles(LookupAll, 'sqlite') # type: ignore[no-untyped-call, misc]
+def _sqlite_lookup_all(element: LookupAll,
+                        compiler: 'sa.Compiled', **kw: Any) -> str:
+    place, col, colname, tokens = list(element.clauses)
+    return "(%s IN (SELECT CAST(value as bigint) FROM"\
+           " (SELECT array_intersect_fuzzy(places) as p FROM"\
+           "   (SELECT places FROM reverse_search_name"\
+           "   WHERE word IN (SELECT value FROM json_each('[' || %s || ']'))"\
+           "     AND column = %s"\
+           "   ORDER BY length(places)) as x) as u,"\
+           " json_each('[' || u.p || ']'))"\
+           " AND array_contains(%s, %s))"\
+             % (compiler.process(place, **kw),
+                compiler.process(tokens, **kw),
+                compiler.process(colname, **kw),
+                compiler.process(col, **kw),
+                compiler.process(tokens, **kw)
+                )
+
+
+
+class LookupAny(LookupType):
+    """ Find all entries that contain at least one of the given tokens.
+        Use an index for the search.
+    """
+    inherit_cache = True
+
+    def __init__(self, table: SaFromClause, column: str, tokens: List[int]) -> None:
+        super().__init__(table.c.place_id, getattr(table.c, column), column,
+                         sa.type_coerce(tokens, IntArray))
+
+@compiles(LookupAny) # type: ignore[no-untyped-call, misc]
+def _default_lookup_any(element: LookupAny,
+                        compiler: 'sa.Compiled', **kw: Any) -> str:
+    _, col, _, tokens = list(element.clauses)
+    return "(%s && %s)" % (compiler.process(col, **kw),
+                           compiler.process(tokens, **kw))
+
+@compiles(LookupAny, 'sqlite') # type: ignore[no-untyped-call, misc]
+def _sqlite_lookup_any(element: LookupAny,
+                        compiler: 'sa.Compiled', **kw: Any) -> str:
+    place, _, colname, tokens = list(element.clauses)
+    return "%s IN (SELECT CAST(value as bigint) FROM"\
+           " (SELECT array_union(places) as p FROM reverse_search_name"\
+           "   WHERE word IN (SELECT value FROM json_each('[' || %s || ']'))"\
+           "     AND column = %s) as u,"\
+           " json_each('[' || u.p || ']'))" % (compiler.process(place, **kw),
+                                               compiler.process(tokens, **kw),
+                                               compiler.process(colname, **kw))
+
+
+
+class Restrict(LookupType):
+    """ Find all entries that contain all of the given tokens.
+        Do not use an index for the search.
+    """
+    inherit_cache = True
+
+    def __init__(self, table: SaFromClause, column: str, tokens: List[int]) -> None:
+        super().__init__(getattr(table.c, column),
+                         sa.type_coerce(tokens, IntArray))
+
+
+@compiles(Restrict) # type: ignore[no-untyped-call, misc]
+def _default_restrict(element: Restrict,
+                        compiler: 'sa.Compiled', **kw: Any) -> str:
+    arg1, arg2 = list(element.clauses)
+    return "(coalesce(null, %s) @> %s)" % (compiler.process(arg1, **kw),
+                                           compiler.process(arg2, **kw))
+
+@compiles(Restrict, 'sqlite') # type: ignore[no-untyped-call, misc]
+def _sqlite_restrict(element: Restrict,
+                        compiler: 'sa.Compiled', **kw: Any) -> str:
+    return "array_contains(%s)" % compiler.process(element.clauses, **kw)

nominatim/api/search/db_searches.py

@@ -0,0 +1,816 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Implementation of the actual database accesses for forward search.
+"""
+from typing import List, Tuple, AsyncIterator, Dict, Any, Callable, cast
+import abc
+
+import sqlalchemy as sa
+
+from nominatim.typing import SaFromClause, SaScalarSelect, SaColumn, \
+                             SaExpression, SaSelect, SaLambdaSelect, SaRow, SaBind
+from nominatim.api.connection import SearchConnection
+from nominatim.api.types import SearchDetails, DataLayer, GeometryFormat, Bbox
+import nominatim.api.results as nres
+from nominatim.api.search.db_search_fields import SearchData, WeightedCategories
+from nominatim.db.sqlalchemy_types import Geometry, IntArray
+
+#pylint: disable=singleton-comparison,not-callable
+#pylint: disable=too-many-branches,too-many-arguments,too-many-locals,too-many-statements
+
+def no_index(expr: SaColumn) -> SaColumn:
+    """ Wrap the given expression, so that the query planner will
+        refrain from using the expression for index lookup.
+    """
+    return sa.func.coalesce(sa.null(), expr) # pylint: disable=not-callable
+
+
+def _details_to_bind_params(details: SearchDetails) -> Dict[str, Any]:
+    """ Create a dictionary from search parameters that can be used
+        as bind parameter for SQL execute.
+    """
+    return {'limit': details.max_results,
+            'min_rank': details.min_rank,
+            'max_rank': details.max_rank,
+            'viewbox': details.viewbox,
+            'viewbox2': details.viewbox_x2,
+            'near': details.near,
+            'near_radius': details.near_radius,
+            'excluded': details.excluded,
+            'countries': details.countries}
+
+
+LIMIT_PARAM: SaBind = sa.bindparam('limit')
+MIN_RANK_PARAM: SaBind = sa.bindparam('min_rank')
+MAX_RANK_PARAM: SaBind = sa.bindparam('max_rank')
+VIEWBOX_PARAM: SaBind = sa.bindparam('viewbox', type_=Geometry)
+VIEWBOX2_PARAM: SaBind = sa.bindparam('viewbox2', type_=Geometry)
+NEAR_PARAM: SaBind = sa.bindparam('near', type_=Geometry)
+NEAR_RADIUS_PARAM: SaBind = sa.bindparam('near_radius')
+COUNTRIES_PARAM: SaBind = sa.bindparam('countries')
+
+
+def filter_by_area(sql: SaSelect, t: SaFromClause,
+                   details: SearchDetails, avoid_index: bool = False) -> SaSelect:
+    """ Apply SQL statements for filtering by viewbox and near point,
+        if applicable.
+    """
+    if details.near is not None and details.near_radius is not None:
+        if details.near_radius < 0.1 and not avoid_index:
+            sql = sql.where(t.c.geometry.within_distance(NEAR_PARAM, NEAR_RADIUS_PARAM))
+        else:
+            sql = sql.where(t.c.geometry.ST_Distance(NEAR_PARAM) <= NEAR_RADIUS_PARAM)
+    if details.viewbox is not None and details.bounded_viewbox:
+        sql = sql.where(t.c.geometry.intersects(VIEWBOX_PARAM,
+                                                use_index=not avoid_index and
+                                                          details.viewbox.area < 0.2))
+
+    return sql
+
+
+def _exclude_places(t: SaFromClause) -> Callable[[], SaExpression]:
+    return lambda: t.c.place_id.not_in(sa.bindparam('excluded'))
+
+
+def _select_placex(t: SaFromClause) -> SaSelect:
+    return sa.select(t.c.place_id, t.c.osm_type, t.c.osm_id, t.c.name,
+                     t.c.class_, t.c.type,
+                     t.c.address, t.c.extratags,
+                     t.c.housenumber, t.c.postcode, t.c.country_code,
+                     t.c.wikipedia,
+                     t.c.parent_place_id, t.c.rank_address, t.c.rank_search,
+                     t.c.linked_place_id, t.c.admin_level,
+                     t.c.centroid,
+                     t.c.geometry.ST_Expand(0).label('bbox'))
+
+
+def _add_geometry_columns(sql: SaLambdaSelect, col: SaColumn, details: SearchDetails) -> SaSelect:
+    out = []
+
+    if details.geometry_simplification > 0.0:
+        col = sa.func.ST_SimplifyPreserveTopology(col, details.geometry_simplification)
+
+    if details.geometry_output & GeometryFormat.GEOJSON:
+        out.append(sa.func.ST_AsGeoJSON(col, 7).label('geometry_geojson'))
+    if details.geometry_output & GeometryFormat.TEXT:
+        out.append(sa.func.ST_AsText(col).label('geometry_text'))
+    if details.geometry_output & GeometryFormat.KML:
+        out.append(sa.func.ST_AsKML(col, 7).label('geometry_kml'))
+    if details.geometry_output & GeometryFormat.SVG:
+        out.append(sa.func.ST_AsSVG(col, 0, 7).label('geometry_svg'))
+
+    return sql.add_columns(*out)
+
+
+def _make_interpolation_subquery(table: SaFromClause, inner: SaFromClause,
+                                 numerals: List[int], details: SearchDetails) -> SaScalarSelect:
+    all_ids = sa.func.ArrayAgg(table.c.place_id)
+    sql = sa.select(all_ids).where(table.c.parent_place_id == inner.c.place_id)
+
+    if len(numerals) == 1:
+        sql = sql.where(sa.between(numerals[0], table.c.startnumber, table.c.endnumber))\
+                 .where((numerals[0] - table.c.startnumber) % table.c.step == 0)
+    else:
+        sql = sql.where(sa.or_(
+                *(sa.and_(sa.between(n, table.c.startnumber, table.c.endnumber),
+                          (n - table.c.startnumber) % table.c.step == 0)
+                  for n in numerals)))
+
+    if details.excluded:
+        sql = sql.where(_exclude_places(table))
+
+    return sql.scalar_subquery()
+
+
+def _filter_by_layer(table: SaFromClause, layers: DataLayer) -> SaColumn:
+    orexpr: List[SaExpression] = []
+    if layers & DataLayer.ADDRESS and layers & DataLayer.POI:
+        orexpr.append(no_index(table.c.rank_address).between(1, 30))
+    elif layers & DataLayer.ADDRESS:
+        orexpr.append(no_index(table.c.rank_address).between(1, 29))
+        orexpr.append(sa.func.IsAddressPoint(table))
+    elif layers & DataLayer.POI:
+        orexpr.append(sa.and_(no_index(table.c.rank_address) == 30,
+                              table.c.class_.not_in(('place', 'building'))))
+
+    if layers & DataLayer.MANMADE:
+        exclude = []
+        if not layers & DataLayer.RAILWAY:
+            exclude.append('railway')
+        if not layers & DataLayer.NATURAL:
+            exclude.extend(('natural', 'water', 'waterway'))
+        orexpr.append(sa.and_(table.c.class_.not_in(tuple(exclude)),
+                              no_index(table.c.rank_address) == 0))
+    else:
+        include = []
+        if layers & DataLayer.RAILWAY:
+            include.append('railway')
+        if layers & DataLayer.NATURAL:
+            include.extend(('natural', 'water', 'waterway'))
+        orexpr.append(sa.and_(table.c.class_.in_(tuple(include)),
+                              no_index(table.c.rank_address) == 0))
+
+    if len(orexpr) == 1:
+        return orexpr[0]
+
+    return sa.or_(*orexpr)
+
+
+def _interpolated_position(table: SaFromClause, nr: SaColumn) -> SaColumn:
+    pos = sa.cast(nr - table.c.startnumber, sa.Float) / (table.c.endnumber - table.c.startnumber)
+    return sa.case(
+            (table.c.endnumber == table.c.startnumber, table.c.linegeo.ST_Centroid()),
+            else_=table.c.linegeo.ST_LineInterpolatePoint(pos)).label('centroid')
+
+
+async def _get_placex_housenumbers(conn: SearchConnection,
+                                   place_ids: List[int],
+                                   details: SearchDetails) -> AsyncIterator[nres.SearchResult]:
+    t = conn.t.placex
+    sql = _select_placex(t).add_columns(t.c.importance)\
+                           .where(t.c.place_id.in_(place_ids))
+
+    if details.geometry_output:
+        sql = _add_geometry_columns(sql, t.c.geometry, details)
+
+    for row in await conn.execute(sql):
+        result = nres.create_from_placex_row(row, nres.SearchResult)
+        assert result
+        result.bbox = Bbox.from_wkb(row.bbox)
+        yield result
+
+
+def _int_list_to_subquery(inp: List[int]) -> 'sa.Subquery':
+    """ Create a subselect that returns the given list of integers
+        as rows in the column 'nr'.
+    """
+    vtab = sa.func.JsonArrayEach(sa.type_coerce(inp, sa.JSON))\
+               .table_valued(sa.column('value', type_=sa.JSON))
+    return sa.select(sa.cast(sa.cast(vtab.c.value, sa.Text), sa.Integer).label('nr')).subquery()
+
+
+async def _get_osmline(conn: SearchConnection, place_ids: List[int],
+                       numerals: List[int],
+                       details: SearchDetails) -> AsyncIterator[nres.SearchResult]:
+    t = conn.t.osmline
+
+    values = _int_list_to_subquery(numerals)
+    sql = sa.select(t.c.place_id, t.c.osm_id,
+                    t.c.parent_place_id, t.c.address,
+                    values.c.nr.label('housenumber'),
+                    _interpolated_position(t, values.c.nr),
+                    t.c.postcode, t.c.country_code)\
+            .where(t.c.place_id.in_(place_ids))\
+            .join(values, values.c.nr.between(t.c.startnumber, t.c.endnumber))
+
+    if details.geometry_output:
+        sub = sql.subquery()
+        sql = _add_geometry_columns(sa.select(sub), sub.c.centroid, details)
+
+    for row in await conn.execute(sql):
+        result = nres.create_from_osmline_row(row, nres.SearchResult)
+        assert result
+        yield result
+
+
+async def _get_tiger(conn: SearchConnection, place_ids: List[int],
+                     numerals: List[int], osm_id: int,
+                     details: SearchDetails) -> AsyncIterator[nres.SearchResult]:
+    t = conn.t.tiger
+    values = _int_list_to_subquery(numerals)
+    sql = sa.select(t.c.place_id, t.c.parent_place_id,
+                    sa.literal('W').label('osm_type'),
+                    sa.literal(osm_id).label('osm_id'),
+                    values.c.nr.label('housenumber'),
+                    _interpolated_position(t, values.c.nr),
+                    t.c.postcode)\
+            .where(t.c.place_id.in_(place_ids))\
+            .join(values, values.c.nr.between(t.c.startnumber, t.c.endnumber))
+
+    if details.geometry_output:
+        sub = sql.subquery()
+        sql = _add_geometry_columns(sa.select(sub), sub.c.centroid, details)
+
+    for row in await conn.execute(sql):
+        result = nres.create_from_tiger_row(row, nres.SearchResult)
+        assert result
+        yield result
+
+
+class AbstractSearch(abc.ABC):
+    """ Encapuslation of a single lookup in the database.
+    """
+    SEARCH_PRIO: int = 2
+
+    def __init__(self, penalty: float) -> None:
+        self.penalty = penalty
+
+    @abc.abstractmethod
+    async def lookup(self, conn: SearchConnection,
+                     details: SearchDetails) -> nres.SearchResults:
+        """ Find results for the search in the database.
+        """
+
+
+class NearSearch(AbstractSearch):
+    """ Category search of a place type near the result of another search.
+    """
+    def __init__(self, penalty: float, categories: WeightedCategories,
+                 search: AbstractSearch) -> None:
+        super().__init__(penalty)
+        self.search = search
+        self.categories = categories
+
+
+    async def lookup(self, conn: SearchConnection,
+                     details: SearchDetails) -> nres.SearchResults:
+        """ Find results for the search in the database.
+        """
+        results = nres.SearchResults()
+        base = await self.search.lookup(conn, details)
+
+        if not base:
+            return results
+
+        base.sort(key=lambda r: (r.accuracy, r.rank_search))
+        max_accuracy = base[0].accuracy + 0.5
+        if base[0].rank_address == 0:
+            min_rank = 0
+            max_rank = 0
+        elif base[0].rank_address < 26:
+            min_rank = 1
+            max_rank = min(25, base[0].rank_address + 4)
+        else:
+            min_rank = 26
+            max_rank = 30
+        base = nres.SearchResults(r for r in base if r.source_table == nres.SourceTable.PLACEX
+                                                     and r.accuracy <= max_accuracy
+                                                     and r.bbox and r.bbox.area < 20
+                                                     and r.rank_address >= min_rank
+                                                     and r.rank_address <= max_rank)
+
+        if base:
+            baseids = [b.place_id for b in base[:5] if b.place_id]
+
+            for category, penalty in self.categories:
+                await self.lookup_category(results, conn, baseids, category, penalty, details)
+                if len(results) >= details.max_results:
+                    break
+
+        return results
+
+
+    async def lookup_category(self, results: nres.SearchResults,
+                              conn: SearchConnection, ids: List[int],
+                              category: Tuple[str, str], penalty: float,
+                              details: SearchDetails) -> None:
+        """ Find places of the given category near the list of
+            place ids and add the results to 'results'.
+        """
+        table = await conn.get_class_table(*category)
+
+        tgeom = conn.t.placex.alias('pgeom')
+
+        if table is None:
+            # No classtype table available, do a simplified lookup in placex.
+            table = conn.t.placex
+            sql = sa.select(table.c.place_id,
+                            sa.func.min(tgeom.c.centroid.ST_Distance(table.c.centroid))
+                              .label('dist'))\
+                    .join(tgeom, table.c.geometry.intersects(tgeom.c.centroid.ST_Expand(0.01)))\
+                    .where(table.c.class_ == category[0])\
+                    .where(table.c.type == category[1])
+        else:
+            # Use classtype table. We can afford to use a larger
+            # radius for the lookup.
+            sql = sa.select(table.c.place_id,
+                            sa.func.min(tgeom.c.centroid.ST_Distance(table.c.centroid))
+                              .label('dist'))\
+                    .join(tgeom,
+                          table.c.centroid.ST_CoveredBy(
+                              sa.case((sa.and_(tgeom.c.rank_address > 9,
+                                                tgeom.c.geometry.is_area()),
+                                       tgeom.c.geometry),
+                                      else_ = tgeom.c.centroid.ST_Expand(0.05))))
+
+        inner = sql.where(tgeom.c.place_id.in_(ids))\
+                   .group_by(table.c.place_id).subquery()
+
+        t = conn.t.placex
+        sql = _select_placex(t).add_columns((-inner.c.dist).label('importance'))\
+                               .join(inner, inner.c.place_id == t.c.place_id)\
+                               .order_by(inner.c.dist)
+
+        sql = sql.where(no_index(t.c.rank_address).between(MIN_RANK_PARAM, MAX_RANK_PARAM))
+        if details.countries:
+            sql = sql.where(t.c.country_code.in_(COUNTRIES_PARAM))
+        if details.excluded:
+            sql = sql.where(_exclude_places(t))
+        if details.layers is not None:
+            sql = sql.where(_filter_by_layer(t, details.layers))
+
+        sql = sql.limit(LIMIT_PARAM)
+        for row in await conn.execute(sql, _details_to_bind_params(details)):
+            result = nres.create_from_placex_row(row, nres.SearchResult)
+            assert result
+            result.accuracy = self.penalty + penalty
+            result.bbox = Bbox.from_wkb(row.bbox)
+            results.append(result)
+
+
+
+class PoiSearch(AbstractSearch):
+    """ Category search in a geographic area.
+    """
+    def __init__(self, sdata: SearchData) -> None:
+        super().__init__(sdata.penalty)
+        self.qualifiers = sdata.qualifiers
+        self.countries = sdata.countries
+
+
+    async def lookup(self, conn: SearchConnection,
+                     details: SearchDetails) -> nres.SearchResults:
+        """ Find results for the search in the database.
+        """
+        bind_params = _details_to_bind_params(details)
+        t = conn.t.placex
+
+        rows: List[SaRow] = []
+
+        if details.near and details.near_radius is not None and details.near_radius < 0.2:
+            # simply search in placex table
+            def _base_query() -> SaSelect:
+                return _select_placex(t) \
+                           .add_columns((-t.c.centroid.ST_Distance(NEAR_PARAM))
+                                         .label('importance'))\
+                           .where(t.c.linked_place_id == None) \
+                           .where(t.c.geometry.within_distance(NEAR_PARAM, NEAR_RADIUS_PARAM)) \
+                           .order_by(t.c.centroid.ST_Distance(NEAR_PARAM)) \
+                           .limit(LIMIT_PARAM)
+
+            classtype = self.qualifiers.values
+            if len(classtype) == 1:
+                cclass, ctype = classtype[0]
+                sql: SaLambdaSelect = sa.lambda_stmt(lambda: _base_query()
+                                                 .where(t.c.class_ == cclass)
+                                                 .where(t.c.type == ctype))
+            else:
+                sql = _base_query().where(sa.or_(*(sa.and_(t.c.class_ == cls, t.c.type == typ)
+                                                   for cls, typ in classtype)))
+
+            if self.countries:
+                sql = sql.where(t.c.country_code.in_(self.countries.values))
+
+            if details.viewbox is not None and details.bounded_viewbox:
+                sql = sql.where(t.c.geometry.intersects(VIEWBOX_PARAM))
+
+            rows.extend(await conn.execute(sql, bind_params))
+        else:
+            # use the class type tables
+            for category in self.qualifiers.values:
+                table = await conn.get_class_table(*category)
+                if table is not None:
+                    sql = _select_placex(t)\
+                               .add_columns(t.c.importance)\
+                               .join(table, t.c.place_id == table.c.place_id)\
+                               .where(t.c.class_ == category[0])\
+                               .where(t.c.type == category[1])
+
+                    if details.viewbox is not None and details.bounded_viewbox:
+                        sql = sql.where(table.c.centroid.intersects(VIEWBOX_PARAM))
+
+                    if details.near and details.near_radius is not None:
+                        sql = sql.order_by(table.c.centroid.ST_Distance(NEAR_PARAM))\
+                                 .where(table.c.centroid.within_distance(NEAR_PARAM,
+                                                                         NEAR_RADIUS_PARAM))
+
+                    if self.countries:
+                        sql = sql.where(t.c.country_code.in_(self.countries.values))
+
+                    sql = sql.limit(LIMIT_PARAM)
+                    rows.extend(await conn.execute(sql, bind_params))
+
+        results = nres.SearchResults()
+        for row in rows:
+            result = nres.create_from_placex_row(row, nres.SearchResult)
+            assert result
+            result.accuracy = self.penalty + self.qualifiers.get_penalty((row.class_, row.type))
+            result.bbox = Bbox.from_wkb(row.bbox)
+            results.append(result)
+
+        return results
+
+
+class CountrySearch(AbstractSearch):
+    """ Search for a country name or country code.
+    """
+    SEARCH_PRIO = 0
+
+    def __init__(self, sdata: SearchData) -> None:
+        super().__init__(sdata.penalty)
+        self.countries = sdata.countries
+
+
+    async def lookup(self, conn: SearchConnection,
+                     details: SearchDetails) -> nres.SearchResults:
+        """ Find results for the search in the database.
+        """
+        t = conn.t.placex
+
+        ccodes = self.countries.values
+        sql = _select_placex(t)\
+                .add_columns(t.c.importance)\
+                .where(t.c.country_code.in_(ccodes))\
+                .where(t.c.rank_address == 4)
+
+        if details.geometry_output:
+            sql = _add_geometry_columns(sql, t.c.geometry, details)
+
+        if details.excluded:
+            sql = sql.where(_exclude_places(t))
+
+        sql = filter_by_area(sql, t, details)
+
+        results = nres.SearchResults()
+        for row in await conn.execute(sql, _details_to_bind_params(details)):
+            result = nres.create_from_placex_row(row, nres.SearchResult)
+            assert result
+            result.accuracy = self.penalty + self.countries.get_penalty(row.country_code, 5.0)
+            result.bbox = Bbox.from_wkb(row.bbox)
+            results.append(result)
+
+        if not results:
+            results = await self.lookup_in_country_table(conn, details)
+
+        if results:
+            details.min_rank = min(5, details.max_rank)
+            details.max_rank = min(25, details.max_rank)
+
+        return results
+
+
+    async def lookup_in_country_table(self, conn: SearchConnection,
+                                      details: SearchDetails) -> nres.SearchResults:
+        """ Look up the country in the fallback country tables.
+        """
+        # Avoid the fallback search when this is a more search. Country results
+        # usually are in the first batch of results and it is not possible
+        # to exclude these fallbacks.
+        if details.excluded:
+            return nres.SearchResults()
+
+        t = conn.t.country_name
+        tgrid = conn.t.country_grid
+
+        sql = sa.select(tgrid.c.country_code,
+                        tgrid.c.geometry.ST_Centroid().ST_Collect().ST_Centroid()
+                              .label('centroid'),
+                        tgrid.c.geometry.ST_Collect().ST_Expand(0).label('bbox'))\
+                .where(tgrid.c.country_code.in_(self.countries.values))\
+                .group_by(tgrid.c.country_code)
+
+        sql = filter_by_area(sql, tgrid, details, avoid_index=True)
+
+        sub = sql.subquery('grid')
+
+        sql = sa.select(t.c.country_code,
+                        t.c.name.merge(t.c.derived_name).label('name'),
+                        sub.c.centroid, sub.c.bbox)\
+                .join(sub, t.c.country_code == sub.c.country_code)
+
+        if details.geometry_output:
+            sql = _add_geometry_columns(sql, sub.c.centroid, details)
+
+        results = nres.SearchResults()
+        for row in await conn.execute(sql, _details_to_bind_params(details)):
+            result = nres.create_from_country_row(row, nres.SearchResult)
+            assert result
+            result.bbox = Bbox.from_wkb(row.bbox)
+            result.accuracy = self.penalty + self.countries.get_penalty(row.country_code, 5.0)
+            results.append(result)
+
+        return results
+
+
+
+class PostcodeSearch(AbstractSearch):
+    """ Search for a postcode.
+    """
+    def __init__(self, extra_penalty: float, sdata: SearchData) -> None:
+        super().__init__(sdata.penalty + extra_penalty)
+        self.countries = sdata.countries
+        self.postcodes = sdata.postcodes
+        self.lookups = sdata.lookups
+        self.rankings = sdata.rankings
+
+
+    async def lookup(self, conn: SearchConnection,
+                     details: SearchDetails) -> nres.SearchResults:
+        """ Find results for the search in the database.
+        """
+        t = conn.t.postcode
+        pcs = self.postcodes.values
+
+        sql = sa.select(t.c.place_id, t.c.parent_place_id,
+                        t.c.rank_search, t.c.rank_address,
+                        t.c.postcode, t.c.country_code,
+                        t.c.geometry.label('centroid'))\
+                .where(t.c.postcode.in_(pcs))
+
+        if details.geometry_output:
+            sql = _add_geometry_columns(sql, t.c.geometry, details)
+
+        penalty: SaExpression = sa.literal(self.penalty)
+
+        if details.viewbox is not None and not details.bounded_viewbox:
+            penalty += sa.case((t.c.geometry.intersects(VIEWBOX_PARAM), 0.0),
+                               (t.c.geometry.intersects(VIEWBOX2_PARAM), 0.5),
+                               else_=1.0)
+
+        if details.near is not None:
+            sql = sql.order_by(t.c.geometry.ST_Distance(NEAR_PARAM))
+
+        sql = filter_by_area(sql, t, details)
+
+        if self.countries:
+            sql = sql.where(t.c.country_code.in_(self.countries.values))
+
+        if details.excluded:
+            sql = sql.where(_exclude_places(t))
+
+        if self.lookups:
+            assert len(self.lookups) == 1
+            tsearch = conn.t.search_name
+            sql = sql.where(tsearch.c.place_id == t.c.parent_place_id)\
+                     .where((tsearch.c.name_vector + tsearch.c.nameaddress_vector)
+                                     .contains(sa.type_coerce(self.lookups[0].tokens,
+                                                              IntArray)))
+
+        for ranking in self.rankings:
+            penalty += ranking.sql_penalty(conn.t.search_name)
+        penalty += sa.case(*((t.c.postcode == v, p) for v, p in self.postcodes),
+                       else_=1.0)
+
+
+        sql = sql.add_columns(penalty.label('accuracy'))
+        sql = sql.order_by('accuracy').limit(LIMIT_PARAM)
+
+        results = nres.SearchResults()
+        for row in await conn.execute(sql, _details_to_bind_params(details)):
+            result = nres.create_from_postcode_row(row, nres.SearchResult)
+            assert result
+            result.accuracy = row.accuracy
+            results.append(result)
+
+        return results
+
+
+
+class PlaceSearch(AbstractSearch):
+    """ Generic search for an address or named place.
+    """
+    SEARCH_PRIO = 1
+
+    def __init__(self, extra_penalty: float, sdata: SearchData, expected_count: int) -> None:
+        super().__init__(sdata.penalty + extra_penalty)
+        self.countries = sdata.countries
+        self.postcodes = sdata.postcodes
+        self.housenumbers = sdata.housenumbers
+        self.qualifiers = sdata.qualifiers
+        self.lookups = sdata.lookups
+        self.rankings = sdata.rankings
+        self.expected_count = expected_count
+
+
+    async def lookup(self, conn: SearchConnection,
+                     details: SearchDetails) -> nres.SearchResults:
+        """ Find results for the search in the database.
+        """
+        t = conn.t.placex
+        tsearch = conn.t.search_name
+
+        sql: SaLambdaSelect = sa.lambda_stmt(lambda:
+                  _select_placex(t).where(t.c.place_id == tsearch.c.place_id))
+
+
+        if details.geometry_output:
+            sql = _add_geometry_columns(sql, t.c.geometry, details)
+
+        penalty: SaExpression = sa.literal(self.penalty)
+        for ranking in self.rankings:
+            penalty += ranking.sql_penalty(tsearch)
+
+        for lookup in self.lookups:
+            sql = sql.where(lookup.sql_condition(tsearch))
+
+        if self.countries:
+            sql = sql.where(tsearch.c.country_code.in_(self.countries.values))
+
+        if self.postcodes:
+            # if a postcode is given, don't search for state or country level objects
+            sql = sql.where(tsearch.c.address_rank > 9)
+            tpc = conn.t.postcode
+            pcs = self.postcodes.values
+            if self.expected_count > 5000:
+                # Many results expected. Restrict by postcode.
+                sql = sql.where(sa.select(tpc.c.postcode)
+                                  .where(tpc.c.postcode.in_(pcs))
+                                  .where(tsearch.c.centroid.within_distance(tpc.c.geometry, 0.12))
+                                  .exists())
+
+            # Less results, only have a preference for close postcodes
+            pc_near = sa.select(sa.func.min(tpc.c.geometry.ST_Distance(tsearch.c.centroid)))\
+                      .where(tpc.c.postcode.in_(pcs))\
+                      .scalar_subquery()
+            penalty += sa.case((t.c.postcode.in_(pcs), 0.0),
+                               else_=sa.func.coalesce(pc_near, cast(SaColumn, 2.0)))
+
+        if details.viewbox is not None:
+            if details.bounded_viewbox:
+                sql = sql.where(tsearch.c.centroid
+                                         .intersects(VIEWBOX_PARAM,
+                                                     use_index=details.viewbox.area < 0.2))
+            elif not self.postcodes and not self.housenumbers and self.expected_count >= 10000:
+                sql = sql.where(tsearch.c.centroid
+                                         .intersects(VIEWBOX2_PARAM,
+                                                     use_index=details.viewbox.area < 0.5))
+            else:
+                penalty += sa.case((t.c.geometry.intersects(VIEWBOX_PARAM, use_index=False), 0.0),
+                                   (t.c.geometry.intersects(VIEWBOX2_PARAM, use_index=False), 0.5),
+                                   else_=1.0)
+
+        if details.near is not None:
+            if details.near_radius is not None:
+                if details.near_radius < 0.1:
+                    sql = sql.where(tsearch.c.centroid.within_distance(NEAR_PARAM,
+                                                                       NEAR_RADIUS_PARAM))
+                else:
+                    sql = sql.where(tsearch.c.centroid
+                                             .ST_Distance(NEAR_PARAM) <  NEAR_RADIUS_PARAM)
+            sql = sql.add_columns((-tsearch.c.centroid.ST_Distance(NEAR_PARAM))
+                                      .label('importance'))
+            sql = sql.order_by(sa.desc(sa.text('importance')))
+        else:
+            if self.expected_count < 10000\
+               or (details.viewbox is not None and details.viewbox.area < 0.5):
+                sql = sql.order_by(
+                        penalty - sa.case((tsearch.c.importance > 0, tsearch.c.importance),
+                                    else_=0.40001-(sa.cast(tsearch.c.search_rank, sa.Float())/75)))
+            sql = sql.add_columns(t.c.importance)
+
+
+        sql = sql.add_columns(penalty.label('accuracy'))
+
+        if self.expected_count < 10000:
+            sql = sql.order_by(sa.text('accuracy'))
+
+        if self.housenumbers:
+            hnr_list = '|'.join(self.housenumbers.values)
+            sql = sql.where(tsearch.c.address_rank.between(16, 30))\
+                     .where(sa.or_(tsearch.c.address_rank < 30,
+                                   sa.func.RegexpWord(hnr_list, t.c.housenumber)))
+
+            # Cross check for housenumbers, need to do that on a rather large
+            # set. Worst case there are 40.000 main streets in OSM.
+            inner = sql.limit(10000).subquery()
+
+            # Housenumbers from placex
+            thnr = conn.t.placex.alias('hnr')
+            pid_list = sa.func.ArrayAgg(thnr.c.place_id)
+            place_sql = sa.select(pid_list)\
+                          .where(thnr.c.parent_place_id == inner.c.place_id)\
+                          .where(sa.func.RegexpWord(hnr_list, thnr.c.housenumber))\
+                          .where(thnr.c.linked_place_id == None)\
+                          .where(thnr.c.indexed_status == 0)
+
+            if details.excluded:
+                place_sql = place_sql.where(thnr.c.place_id.not_in(sa.bindparam('excluded')))
+            if self.qualifiers:
+                place_sql = place_sql.where(self.qualifiers.sql_restrict(thnr))
+
+            numerals = [int(n) for n in self.housenumbers.values
+                        if n.isdigit() and len(n) < 8]
+            interpol_sql: SaColumn
+            tiger_sql: SaColumn
+            if numerals and \
+               (not self.qualifiers or ('place', 'house') in self.qualifiers.values):
+                # Housenumbers from interpolations
+                interpol_sql = _make_interpolation_subquery(conn.t.osmline, inner,
+                                                            numerals, details)
+                # Housenumbers from Tiger
+                tiger_sql = sa.case((inner.c.country_code == 'us',
+                                     _make_interpolation_subquery(conn.t.tiger, inner,
+                                                                  numerals, details)
+                                    ), else_=None)
+            else:
+                interpol_sql = sa.null()
+                tiger_sql = sa.null()
+
+            unsort = sa.select(inner, place_sql.scalar_subquery().label('placex_hnr'),
+                               interpol_sql.label('interpol_hnr'),
+                               tiger_sql.label('tiger_hnr')).subquery('unsort')
+            sql = sa.select(unsort)\
+                    .order_by(sa.case((unsort.c.placex_hnr != None, 1),
+                                      (unsort.c.interpol_hnr != None, 2),
+                                      (unsort.c.tiger_hnr != None, 3),
+                                      else_=4),
+                              unsort.c.accuracy)
+        else:
+            sql = sql.where(t.c.linked_place_id == None)\
+                     .where(t.c.indexed_status == 0)
+            if self.qualifiers:
+                sql = sql.where(self.qualifiers.sql_restrict(t))
+            if details.excluded:
+                sql = sql.where(_exclude_places(tsearch))
+            if details.min_rank > 0:
+                sql = sql.where(sa.or_(tsearch.c.address_rank >= MIN_RANK_PARAM,
+                                       tsearch.c.search_rank >= MIN_RANK_PARAM))
+            if details.max_rank < 30:
+                sql = sql.where(sa.or_(tsearch.c.address_rank <= MAX_RANK_PARAM,
+                                       tsearch.c.search_rank <= MAX_RANK_PARAM))
+            if details.layers is not None:
+                sql = sql.where(_filter_by_layer(t, details.layers))
+
+        sql = sql.limit(LIMIT_PARAM)
+
+        results = nres.SearchResults()
+        for row in await conn.execute(sql, _details_to_bind_params(details)):
+            result = nres.create_from_placex_row(row, nres.SearchResult)
+            assert result
+            result.bbox = Bbox.from_wkb(row.bbox)
+            result.accuracy = row.accuracy
+            if self.housenumbers and row.rank_address < 30:
+                if row.placex_hnr:
+                    subs = _get_placex_housenumbers(conn, row.placex_hnr, details)
+                elif row.interpol_hnr:
+                    subs = _get_osmline(conn, row.interpol_hnr, numerals, details)
+                elif row.tiger_hnr:
+                    subs = _get_tiger(conn, row.tiger_hnr, numerals, row.osm_id, details)
+                else:
+                    subs = None
+
+                if subs is not None:
+                    async for sub in subs:
+                        assert sub.housenumber
+                        sub.accuracy = result.accuracy
+                        if not any(nr in self.housenumbers.values
+                                   for nr in sub.housenumber.split(';')):
+                            sub.accuracy += 0.6
+                        results.append(sub)
+
+                # Only add the street as a result, if it meets all other
+                # filter conditions.
+                if (not details.excluded or result.place_id not in details.excluded)\
+                   and (not self.qualifiers or result.category in self.qualifiers.values)\
+                   and result.rank_address >= details.min_rank:
+                    result.accuracy += 1.0 # penalty for missing housenumber
+                    results.append(result)
+            else:
+                results.append(result)
+
+        return results

nominatim/api/search/geocoder.py

@@ -0,0 +1,274 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Public interface to the search code.
+"""
+from typing import List, Any, Optional, Iterator, Tuple, Dict
+import itertools
+import re
+import datetime as dt
+import difflib
+
+from nominatim.api.connection import SearchConnection
+from nominatim.api.types import SearchDetails
+from nominatim.api.results import SearchResult, SearchResults, add_result_details
+from nominatim.api.search.token_assignment import yield_token_assignments
+from nominatim.api.search.db_search_builder import SearchBuilder, build_poi_search, wrap_near_search
+from nominatim.api.search.db_searches import AbstractSearch
+from nominatim.api.search.query_analyzer_factory import make_query_analyzer, AbstractQueryAnalyzer
+from nominatim.api.search.query import Phrase, QueryStruct
+from nominatim.api.logging import log
+
+class ForwardGeocoder:
+    """ Main class responsible for place search.
+    """
+
+    def __init__(self, conn: SearchConnection,
+                 params: SearchDetails, timeout: Optional[int]) -> None:
+        self.conn = conn
+        self.params = params
+        self.timeout = dt.timedelta(seconds=timeout or 1000000)
+        self.query_analyzer: Optional[AbstractQueryAnalyzer] = None
+
+
+    @property
+    def limit(self) -> int:
+        """ Return the configured maximum number of search results.
+        """
+        return self.params.max_results
+
+
+    async def build_searches(self,
+                             phrases: List[Phrase]) -> Tuple[QueryStruct, List[AbstractSearch]]:
+        """ Analyse the query and return the tokenized query and list of
+            possible searches over it.
+        """
+        if self.query_analyzer is None:
+            self.query_analyzer = await make_query_analyzer(self.conn)
+
+        query = await self.query_analyzer.analyze_query(phrases)
+
+        searches: List[AbstractSearch] = []
+        if query.num_token_slots() > 0:
+            # 2. Compute all possible search interpretations
+            log().section('Compute abstract searches')
+            search_builder = SearchBuilder(query, self.params)
+            num_searches = 0
+            for assignment in yield_token_assignments(query):
+                searches.extend(search_builder.build(assignment))
+                if num_searches < len(searches):
+                    log().table_dump('Searches for assignment',
+                                     _dump_searches(searches, query, num_searches))
+                num_searches = len(searches)
+            searches.sort(key=lambda s: (s.penalty, s.SEARCH_PRIO))
+
+        return query, searches
+
+
+    async def execute_searches(self, query: QueryStruct,
+                               searches: List[AbstractSearch]) -> SearchResults:
+        """ Run the abstract searches against the database until a result
+            is found.
+        """
+        log().section('Execute database searches')
+        results: Dict[Any, SearchResult] = {}
+
+        end_time = dt.datetime.now() + self.timeout
+
+        min_ranking = searches[0].penalty + 2.0
+        prev_penalty = 0.0
+        for i, search in enumerate(searches):
+            if search.penalty > prev_penalty and (search.penalty > min_ranking or i > 20):
+                break
+            log().table_dump(f"{i + 1}. Search", _dump_searches([search], query))
+            log().var_dump('Params', self.params)
+            lookup_results = await search.lookup(self.conn, self.params)
+            for result in lookup_results:
+                rhash = (result.source_table, result.place_id,
+                         result.housenumber, result.country_code)
+                prevresult = results.get(rhash)
+                if prevresult:
+                    prevresult.accuracy = min(prevresult.accuracy, result.accuracy)
+                else:
+                    results[rhash] = result
+                min_ranking = min(min_ranking, result.accuracy * 1.2)
+            log().result_dump('Results', ((r.accuracy, r) for r in lookup_results))
+            prev_penalty = search.penalty
+            if dt.datetime.now() >= end_time:
+                break
+
+        return SearchResults(results.values())
+
+
+    def pre_filter_results(self, results: SearchResults) -> SearchResults:
+        """ Remove results that are significantly worse than the
+            best match.
+        """
+        if results:
+            max_ranking = min(r.ranking for r in results) + 0.5
+            results = SearchResults(r for r in results if r.ranking < max_ranking)
+
+        return results
+
+
+    def sort_and_cut_results(self, results: SearchResults) -> SearchResults:
+        """ Remove badly matching results, sort by ranking and
+            limit to the configured number of results.
+        """
+        if results:
+            results.sort(key=lambda r: r.ranking)
+            min_rank = results[0].rank_search
+            min_ranking = results[0].ranking
+            results = SearchResults(r for r in results
+                                    if r.ranking + 0.03 * (r.rank_search - min_rank)
+                                       < min_ranking + 0.5)
+
+            results = SearchResults(results[:self.limit])
+
+        return results
+
+
+    def rerank_by_query(self, query: QueryStruct, results: SearchResults) -> None:
+        """ Adjust the accuracy of the localized result according to how well
+            they match the original query.
+        """
+        assert self.query_analyzer is not None
+        qwords = [word for phrase in query.source
+                       for word in re.split('[, ]+', phrase.text) if word]
+        if not qwords:
+            return
+
+        for result in results:
+            # Negative importance indicates ordering by distance, which is
+            # more important than word matching.
+            if not result.display_name\
+               or (result.importance is not None and result.importance < 0):
+                continue
+            distance = 0.0
+            norm = self.query_analyzer.normalize_text(' '.join((result.display_name,
+                                                                result.country_code or '')))
+            words = set((w for w in norm.split(' ') if w))
+            if not words:
+                continue
+            for qword in qwords:
+                wdist = max(difflib.SequenceMatcher(a=qword, b=w).quick_ratio() for w in words)
+                if wdist < 0.5:
+                    distance += len(qword)
+                else:
+                    distance += (1.0 - wdist) * len(qword)
+            # Compensate for the fact that country names do not get a
+            # match penalty yet by the tokenizer.
+            # Temporary hack that needs to be removed!
+            if result.rank_address == 4:
+                distance *= 2
+            result.accuracy += distance * 0.4 / sum(len(w) for w in qwords)
+
+
+    async def lookup_pois(self, categories: List[Tuple[str, str]],
+                          phrases: List[Phrase]) -> SearchResults:
+        """ Look up places by category. If phrase is given, a place search
+            over the phrase will be executed first and places close to the
+            results returned.
+        """
+        log().function('forward_lookup_pois', categories=categories, params=self.params)
+
+        if phrases:
+            query, searches = await self.build_searches(phrases)
+
+            if query:
+                searches = [wrap_near_search(categories, s) for s in searches[:50]]
+                results = await self.execute_searches(query, searches)
+                results = self.pre_filter_results(results)
+                await add_result_details(self.conn, results, self.params)
+                log().result_dump('Preliminary Results', ((r.accuracy, r) for r in results))
+                results = self.sort_and_cut_results(results)
+            else:
+                results = SearchResults()
+        else:
+            search = build_poi_search(categories, self.params.countries)
+            results = await search.lookup(self.conn, self.params)
+            await add_result_details(self.conn, results, self.params)
+
+        log().result_dump('Final Results', ((r.accuracy, r) for r in results))
+
+        return results
+
+
+    async def lookup(self, phrases: List[Phrase]) -> SearchResults:
+        """ Look up a single free-text query.
+        """
+        log().function('forward_lookup', phrases=phrases, params=self.params)
+        results = SearchResults()
+
+        if self.params.is_impossible():
+            return results
+
+        query, searches = await self.build_searches(phrases)
+
+        if searches:
+            # Execute SQL until an appropriate result is found.
+            results = await self.execute_searches(query, searches[:50])
+            results = self.pre_filter_results(results)
+            await add_result_details(self.conn, results, self.params)
+            log().result_dump('Preliminary Results', ((r.accuracy, r) for r in results))
+            self.rerank_by_query(query, results)
+            log().result_dump('Results after reranking', ((r.accuracy, r) for r in results))
+            results = self.sort_and_cut_results(results)
+            log().result_dump('Final Results', ((r.accuracy, r) for r in results))
+
+        return results
+
+
+# pylint: disable=invalid-name,too-many-locals
+def _dump_searches(searches: List[AbstractSearch], query: QueryStruct,
+                   start: int = 0) -> Iterator[Optional[List[Any]]]:
+    yield ['Penalty', 'Lookups', 'Housenr', 'Postcode', 'Countries',
+           'Qualifier', 'Catgeory', 'Rankings']
+
+    def tk(tl: List[int]) -> str:
+        tstr = [f"{query.find_lookup_word_by_id(t)}({t})" for t in tl]
+
+        return f"[{','.join(tstr)}]"
+
+    def fmt_ranking(f: Any) -> str:
+        if not f:
+            return ''
+        ranks = ','.join((f"{tk(r.tokens)}^{r.penalty:.3g}" for r in f.rankings))
+        if len(ranks) > 100:
+            ranks = ranks[:100] + '...'
+        return f"{f.column}({ranks},def={f.default:.3g})"
+
+    def fmt_lookup(l: Any) -> str:
+        if not l:
+            return ''
+
+        return f"{l.lookup_type}({l.column}{tk(l.tokens)})"
+
+
+    def fmt_cstr(c: Any) -> str:
+        if not c:
+            return ''
+
+        return f'{c[0]}^{c[1]}'
+
+    for search in searches[start:]:
+        fields = ('lookups', 'rankings', 'countries', 'housenumbers',
+                  'postcodes', 'qualifiers')
+        if hasattr(search, 'search'):
+            iters = itertools.zip_longest([f"{search.penalty:.3g}"],
+                                          *(getattr(search.search, attr, []) for attr in fields),
+                                          getattr(search, 'categories', []),
+                                          fillvalue='')
+        else:
+            iters = itertools.zip_longest([f"{search.penalty:.3g}"],
+                                          *(getattr(search, attr, []) for attr in fields),
+                                          [],
+                                          fillvalue='')
+        for penalty, lookup, rank, cc, hnr, pc, qual, cat in iters:
+            yield [penalty, fmt_lookup(lookup), fmt_cstr(hnr),
+                   fmt_cstr(pc), fmt_cstr(cc), fmt_cstr(qual), fmt_cstr(cat), fmt_ranking(rank)]
+        yield None

nominatim/api/search/icu_tokenizer.py

@@ -0,0 +1,312 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Implementation of query analysis for the ICU tokenizer.
+"""
+from typing import Tuple, Dict, List, Optional, NamedTuple, Iterator, Any, cast
+from collections import defaultdict
+import dataclasses
+import difflib
+
+from icu import Transliterator
+
+import sqlalchemy as sa
+
+from nominatim.typing import SaRow
+from nominatim.api.connection import SearchConnection
+from nominatim.api.logging import log
+from nominatim.api.search import query as qmod
+from nominatim.api.search.query_analyzer_factory import AbstractQueryAnalyzer
+from nominatim.db.sqlalchemy_types import Json
+
+
+DB_TO_TOKEN_TYPE = {
+    'W': qmod.TokenType.WORD,
+    'w': qmod.TokenType.PARTIAL,
+    'H': qmod.TokenType.HOUSENUMBER,
+    'P': qmod.TokenType.POSTCODE,
+    'C': qmod.TokenType.COUNTRY
+}
+
+
+class QueryPart(NamedTuple):
+    """ Normalized and transliterated form of a single term in the query.
+        When the term came out of a split during the transliteration,
+        the normalized string is the full word before transliteration.
+        The word number keeps track of the word before transliteration
+        and can be used to identify partial transliterated terms.
+    """
+    token: str
+    normalized: str
+    word_number: int
+
+
+QueryParts = List[QueryPart]
+WordDict = Dict[str, List[qmod.TokenRange]]
+
+def yield_words(terms: List[QueryPart], start: int) -> Iterator[Tuple[str, qmod.TokenRange]]:
+    """ Return all combinations of words in the terms list after the
+        given position.
+    """
+    total = len(terms)
+    for first in range(start, total):
+        word = terms[first].token
+        yield word, qmod.TokenRange(first, first + 1)
+        for last in range(first + 1, min(first + 20, total)):
+            word = ' '.join((word, terms[last].token))
+            yield word, qmod.TokenRange(first, last + 1)
+
+
+@dataclasses.dataclass
+class ICUToken(qmod.Token):
+    """ Specialised token for ICU tokenizer.
+    """
+    word_token: str
+    info: Optional[Dict[str, Any]]
+
+    def get_category(self) -> Tuple[str, str]:
+        assert self.info
+        return self.info.get('class', ''), self.info.get('type', '')
+
+
+    def rematch(self, norm: str) -> None:
+        """ Check how well the token matches the given normalized string
+            and add a penalty, if necessary.
+        """
+        if not self.lookup_word:
+            return
+
+        seq = difflib.SequenceMatcher(a=self.lookup_word, b=norm)
+        distance = 0
+        for tag, afrom, ato, bfrom, bto in seq.get_opcodes():
+            if tag in ('delete', 'insert') and (afrom == 0 or ato == len(self.lookup_word)):
+                distance += 1
+            elif tag == 'replace':
+                distance += max((ato-afrom), (bto-bfrom))
+            elif tag != 'equal':
+                distance += abs((ato-afrom) - (bto-bfrom))
+        self.penalty += (distance/len(self.lookup_word))
+
+
+    @staticmethod
+    def from_db_row(row: SaRow) -> 'ICUToken':
+        """ Create a ICUToken from the row of the word table.
+        """
+        count = 1 if row.info is None else row.info.get('count', 1)
+
+        penalty = 0.0
+        if row.type == 'w':
+            penalty = 0.3
+        elif row.type == 'W':
+            if len(row.word_token) == 1 and row.word_token == row.word:
+                penalty = 0.2 if row.word.isdigit() else 0.3
+        elif row.type == 'H':
+            penalty = sum(0.1 for c in row.word_token if c != ' ' and not c.isdigit())
+            if all(not c.isdigit() for c in row.word_token):
+                penalty += 0.2 * (len(row.word_token) - 1)
+        elif row.type == 'C':
+            if len(row.word_token) == 1:
+                penalty = 0.3
+
+        if row.info is None:
+            lookup_word = row.word
+        else:
+            lookup_word = row.info.get('lookup', row.word)
+        if lookup_word:
+            lookup_word = lookup_word.split('@', 1)[0]
+        else:
+            lookup_word = row.word_token
+
+        return ICUToken(penalty=penalty, token=row.word_id, count=count,
+                        lookup_word=lookup_word, is_indexed=True,
+                        word_token=row.word_token, info=row.info)
+
+
+
+class ICUQueryAnalyzer(AbstractQueryAnalyzer):
+    """ Converter for query strings into a tokenized query
+        using the tokens created by a ICU tokenizer.
+    """
+
+    def __init__(self, conn: SearchConnection) -> None:
+        self.conn = conn
+
+
+    async def setup(self) -> None:
+        """ Set up static data structures needed for the analysis.
+        """
+        async def _make_normalizer() -> Any:
+            rules = await self.conn.get_property('tokenizer_import_normalisation')
+            return Transliterator.createFromRules("normalization", rules)
+
+        self.normalizer = await self.conn.get_cached_value('ICUTOK', 'normalizer',
+                                                           _make_normalizer)
+
+        async def _make_transliterator() -> Any:
+            rules = await self.conn.get_property('tokenizer_import_transliteration')
+            return Transliterator.createFromRules("transliteration", rules)
+
+        self.transliterator = await self.conn.get_cached_value('ICUTOK', 'transliterator',
+                                                               _make_transliterator)
+
+        if 'word' not in self.conn.t.meta.tables:
+            sa.Table('word', self.conn.t.meta,
+                     sa.Column('word_id', sa.Integer),
+                     sa.Column('word_token', sa.Text, nullable=False),
+                     sa.Column('type', sa.Text, nullable=False),
+                     sa.Column('word', sa.Text),
+                     sa.Column('info', Json))
+
+
+    async def analyze_query(self, phrases: List[qmod.Phrase]) -> qmod.QueryStruct:
+        """ Analyze the given list of phrases and return the
+            tokenized query.
+        """
+        log().section('Analyze query (using ICU tokenizer)')
+        normalized = list(filter(lambda p: p.text,
+                                 (qmod.Phrase(p.ptype, self.normalize_text(p.text))
+                                  for p in phrases)))
+        query = qmod.QueryStruct(normalized)
+        log().var_dump('Normalized query', query.source)
+        if not query.source:
+            return query
+
+        parts, words = self.split_query(query)
+        log().var_dump('Transliterated query', lambda: _dump_transliterated(query, parts))
+
+        for row in await self.lookup_in_db(list(words.keys())):
+            for trange in words[row.word_token]:
+                token = ICUToken.from_db_row(row)
+                if row.type == 'S':
+                    if row.info['op'] in ('in', 'near'):
+                        if trange.start == 0:
+                            query.add_token(trange, qmod.TokenType.NEAR_ITEM, token)
+                    else:
+                        if trange.start == 0 and trange.end == query.num_token_slots():
+                            query.add_token(trange, qmod.TokenType.NEAR_ITEM, token)
+                        else:
+                            query.add_token(trange, qmod.TokenType.QUALIFIER, token)
+                else:
+                    query.add_token(trange, DB_TO_TOKEN_TYPE[row.type], token)
+
+        self.add_extra_tokens(query, parts)
+        self.rerank_tokens(query, parts)
+
+        log().table_dump('Word tokens', _dump_word_tokens(query))
+
+        return query
+
+
+    def normalize_text(self, text: str) -> str:
+        """ Bring the given text into a normalized form. That is the
+            standardized form search will work with. All information removed
+            at this stage is inevitably lost.
+        """
+        return cast(str, self.normalizer.transliterate(text))
+
+
+    def split_query(self, query: qmod.QueryStruct) -> Tuple[QueryParts, WordDict]:
+        """ Transliterate the phrases and split them into tokens.
+
+            Returns the list of transliterated tokens together with their
+            normalized form and a dictionary of words for lookup together
+            with their position.
+        """
+        parts: QueryParts = []
+        phrase_start = 0
+        words = defaultdict(list)
+        wordnr = 0
+        for phrase in query.source:
+            query.nodes[-1].ptype = phrase.ptype
+            for word in phrase.text.split(' '):
+                trans = self.transliterator.transliterate(word)
+                if trans:
+                    for term in trans.split(' '):
+                        if term:
+                            parts.append(QueryPart(term, word, wordnr))
+                            query.add_node(qmod.BreakType.TOKEN, phrase.ptype)
+                    query.nodes[-1].btype = qmod.BreakType.WORD
+                wordnr += 1
+            query.nodes[-1].btype = qmod.BreakType.PHRASE
+
+            for word, wrange in yield_words(parts, phrase_start):
+                words[word].append(wrange)
+
+            phrase_start = len(parts)
+        query.nodes[-1].btype = qmod.BreakType.END
+
+        return parts, words
+
+
+    async def lookup_in_db(self, words: List[str]) -> 'sa.Result[Any]':
+        """ Return the token information from the database for the
+            given word tokens.
+        """
+        t = self.conn.t.meta.tables['word']
+        return await self.conn.execute(t.select().where(t.c.word_token.in_(words)))
+
+
+    def add_extra_tokens(self, query: qmod.QueryStruct, parts: QueryParts) -> None:
+        """ Add tokens to query that are not saved in the database.
+        """
+        for part, node, i in zip(parts, query.nodes, range(1000)):
+            if len(part.token) <= 4 and part[0].isdigit()\
+               and not node.has_tokens(i+1, qmod.TokenType.HOUSENUMBER):
+                query.add_token(qmod.TokenRange(i, i+1), qmod.TokenType.HOUSENUMBER,
+                                ICUToken(0.5, 0, 1, part.token, True, part.token, None))
+
+
+    def rerank_tokens(self, query: qmod.QueryStruct, parts: QueryParts) -> None:
+        """ Add penalties to tokens that depend on presence of other token.
+        """
+        for i, node, tlist in query.iter_token_lists():
+            if tlist.ttype == qmod.TokenType.POSTCODE:
+                for repl in node.starting:
+                    if repl.end == tlist.end and repl.ttype != qmod.TokenType.POSTCODE \
+                       and (repl.ttype != qmod.TokenType.HOUSENUMBER
+                            or len(tlist.tokens[0].lookup_word) > 4):
+                        repl.add_penalty(0.39)
+            elif tlist.ttype == qmod.TokenType.HOUSENUMBER \
+                 and len(tlist.tokens[0].lookup_word) <= 3:
+                if any(c.isdigit() for c in tlist.tokens[0].lookup_word):
+                    for repl in node.starting:
+                        if repl.end == tlist.end and repl.ttype != qmod.TokenType.HOUSENUMBER:
+                            repl.add_penalty(0.5 - tlist.tokens[0].penalty)
+            elif tlist.ttype not in (qmod.TokenType.COUNTRY, qmod.TokenType.PARTIAL):
+                norm = parts[i].normalized
+                for j in range(i + 1, tlist.end):
+                    if parts[j - 1].word_number != parts[j].word_number:
+                        norm += '  ' + parts[j].normalized
+                for token in tlist.tokens:
+                    cast(ICUToken, token).rematch(norm)
+
+
+def _dump_transliterated(query: qmod.QueryStruct, parts: QueryParts) -> str:
+    out = query.nodes[0].btype.value
+    for node, part in zip(query.nodes[1:], parts):
+        out += part.token + node.btype.value
+    return out
+
+
+def _dump_word_tokens(query: qmod.QueryStruct) -> Iterator[List[Any]]:
+    yield ['type', 'token', 'word_token', 'lookup_word', 'penalty', 'count', 'info']
+    for node in query.nodes:
+        for tlist in node.starting:
+            for token in tlist.tokens:
+                t = cast(ICUToken, token)
+                yield [tlist.ttype.name, t.token, t.word_token or '',
+                       t.lookup_word or '', t.penalty, t.count, t.info]
+
+
+async def create_query_analyzer(conn: SearchConnection) -> AbstractQueryAnalyzer:
+    """ Create and set up a new query analyzer for a database based
+        on the ICU tokenizer.
+    """
+    out = ICUQueryAnalyzer(conn)
+    await out.setup()
+
+    return out

nominatim/api/search/legacy_tokenizer.py

@@ -0,0 +1,271 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Implementation of query analysis for the legacy tokenizer.
+"""
+from typing import Tuple, Dict, List, Optional, Iterator, Any, cast
+from copy import copy
+from collections import defaultdict
+import dataclasses
+
+import sqlalchemy as sa
+
+from nominatim.typing import SaRow
+from nominatim.api.connection import SearchConnection
+from nominatim.api.logging import log
+from nominatim.api.search import query as qmod
+from nominatim.api.search.query_analyzer_factory import AbstractQueryAnalyzer
+
+def yield_words(terms: List[str], start: int) -> Iterator[Tuple[str, qmod.TokenRange]]:
+    """ Return all combinations of words in the terms list after the
+        given position.
+    """
+    total = len(terms)
+    for first in range(start, total):
+        word = terms[first]
+        yield word, qmod.TokenRange(first, first + 1)
+        for last in range(first + 1, min(first + 20, total)):
+            word = ' '.join((word, terms[last]))
+            yield word, qmod.TokenRange(first, last + 1)
+
+
+@dataclasses.dataclass
+class LegacyToken(qmod.Token):
+    """ Specialised token for legacy tokenizer.
+    """
+    word_token: str
+    category: Optional[Tuple[str, str]]
+    country: Optional[str]
+    operator: Optional[str]
+
+    @property
+    def info(self) -> Dict[str, Any]:
+        """ Dictionary of additional properties of the token.
+            Should only be used for debugging purposes.
+        """
+        return {'category': self.category,
+                'country': self.country,
+                'operator': self.operator}
+
+
+    def get_category(self) -> Tuple[str, str]:
+        assert self.category
+        return self.category
+
+
+class LegacyQueryAnalyzer(AbstractQueryAnalyzer):
+    """ Converter for query strings into a tokenized query
+        using the tokens created by a legacy tokenizer.
+    """
+
+    def __init__(self, conn: SearchConnection) -> None:
+        self.conn = conn
+
+    async def setup(self) -> None:
+        """ Set up static data structures needed for the analysis.
+        """
+        self.max_word_freq = int(await self.conn.get_property('tokenizer_maxwordfreq'))
+        if 'word' not in self.conn.t.meta.tables:
+            sa.Table('word', self.conn.t.meta,
+                     sa.Column('word_id', sa.Integer),
+                     sa.Column('word_token', sa.Text, nullable=False),
+                     sa.Column('word', sa.Text),
+                     sa.Column('class', sa.Text),
+                     sa.Column('type', sa.Text),
+                     sa.Column('country_code', sa.Text),
+                     sa.Column('search_name_count', sa.Integer),
+                     sa.Column('operator', sa.Text))
+
+
+    async def analyze_query(self, phrases: List[qmod.Phrase]) -> qmod.QueryStruct:
+        """ Analyze the given list of phrases and return the
+            tokenized query.
+        """
+        log().section('Analyze query (using Legacy tokenizer)')
+
+        normalized = []
+        if phrases:
+            for row in await self.conn.execute(sa.select(*(sa.func.make_standard_name(p.text)
+                                                           for p in phrases))):
+                normalized = [qmod.Phrase(p.ptype, r) for r, p in zip(row, phrases) if r]
+                break
+
+        query = qmod.QueryStruct(normalized)
+        log().var_dump('Normalized query', query.source)
+        if not query.source:
+            return query
+
+        parts, words = self.split_query(query)
+        lookup_words = list(words.keys())
+        log().var_dump('Split query', parts)
+        log().var_dump('Extracted words', lookup_words)
+
+        for row in await self.lookup_in_db(lookup_words):
+            for trange in words[row.word_token.strip()]:
+                token, ttype = self.make_token(row)
+                if ttype == qmod.TokenType.NEAR_ITEM:
+                    if trange.start == 0:
+                        query.add_token(trange, qmod.TokenType.NEAR_ITEM, token)
+                elif ttype == qmod.TokenType.QUALIFIER:
+                    query.add_token(trange, qmod.TokenType.QUALIFIER, token)
+                    if trange.start == 0 or trange.end == query.num_token_slots():
+                        token = copy(token)
+                        token.penalty += 0.1 * (query.num_token_slots())
+                        query.add_token(trange, qmod.TokenType.NEAR_ITEM, token)
+                elif ttype != qmod.TokenType.PARTIAL or trange.start + 1 == trange.end:
+                    query.add_token(trange, ttype, token)
+
+        self.add_extra_tokens(query, parts)
+        self.rerank_tokens(query)
+
+        log().table_dump('Word tokens', _dump_word_tokens(query))
+
+        return query
+
+
+    def normalize_text(self, text: str) -> str:
+        """ Bring the given text into a normalized form.
+
+            This only removes case, so some difference with the normalization
+            in the phrase remains.
+        """
+        return text.lower()
+
+
+    def split_query(self, query: qmod.QueryStruct) -> Tuple[List[str],
+                                                            Dict[str, List[qmod.TokenRange]]]:
+        """ Transliterate the phrases and split them into tokens.
+
+            Returns a list of transliterated tokens and a dictionary
+            of words for lookup together with their position.
+        """
+        parts: List[str] = []
+        phrase_start = 0
+        words = defaultdict(list)
+        for phrase in query.source:
+            query.nodes[-1].ptype = phrase.ptype
+            for trans in phrase.text.split(' '):
+                if trans:
+                    for term in trans.split(' '):
+                        if term:
+                            parts.append(trans)
+                            query.add_node(qmod.BreakType.TOKEN, phrase.ptype)
+                    query.nodes[-1].btype = qmod.BreakType.WORD
+            query.nodes[-1].btype = qmod.BreakType.PHRASE
+            for word, wrange in yield_words(parts, phrase_start):
+                words[word].append(wrange)
+            phrase_start = len(parts)
+        query.nodes[-1].btype = qmod.BreakType.END
+
+        return parts, words
+
+
+    async def lookup_in_db(self, words: List[str]) -> 'sa.Result[Any]':
+        """ Return the token information from the database for the
+            given word tokens.
+        """
+        t = self.conn.t.meta.tables['word']
+
+        sql = t.select().where(t.c.word_token.in_(words + [' ' + w for w in words]))
+
+        return await self.conn.execute(sql)
+
+
+    def make_token(self, row: SaRow) -> Tuple[LegacyToken, qmod.TokenType]:
+        """ Create a LegacyToken from the row of the word table.
+            Also determines the type of token.
+        """
+        penalty = 0.0
+        is_indexed = True
+
+        rowclass = getattr(row, 'class')
+
+        if row.country_code is not None:
+            ttype = qmod.TokenType.COUNTRY
+            lookup_word = row.country_code
+        elif rowclass is not None:
+            if rowclass == 'place' and  row.type == 'house':
+                ttype = qmod.TokenType.HOUSENUMBER
+                lookup_word = row.word_token[1:]
+            elif rowclass == 'place' and  row.type == 'postcode':
+                ttype = qmod.TokenType.POSTCODE
+                lookup_word = row.word_token[1:]
+            else:
+                ttype = qmod.TokenType.NEAR_ITEM if row.operator in ('in', 'near')\
+                        else qmod.TokenType.QUALIFIER
+                lookup_word = row.word
+        elif row.word_token.startswith(' '):
+            ttype = qmod.TokenType.WORD
+            lookup_word = row.word or row.word_token[1:]
+        else:
+            ttype = qmod.TokenType.PARTIAL
+            lookup_word = row.word_token
+            penalty = 0.21
+            if row.search_name_count > self.max_word_freq:
+                is_indexed = False
+
+        return LegacyToken(penalty=penalty, token=row.word_id,
+                           count=row.search_name_count or 1,
+                           lookup_word=lookup_word,
+                           word_token=row.word_token.strip(),
+                           category=(rowclass, row.type) if rowclass is not None else None,
+                           country=row.country_code,
+                           operator=row.operator,
+                           is_indexed=is_indexed),\
+               ttype
+
+
+    def add_extra_tokens(self, query: qmod.QueryStruct, parts: List[str]) -> None:
+        """ Add tokens to query that are not saved in the database.
+        """
+        for part, node, i in zip(parts, query.nodes, range(1000)):
+            if len(part) <= 4 and part.isdigit()\
+               and not node.has_tokens(i+1, qmod.TokenType.HOUSENUMBER):
+                query.add_token(qmod.TokenRange(i, i+1), qmod.TokenType.HOUSENUMBER,
+                                LegacyToken(penalty=0.5, token=0, count=1,
+                                            lookup_word=part, word_token=part,
+                                            category=None, country=None,
+                                            operator=None, is_indexed=True))
+
+
+    def rerank_tokens(self, query: qmod.QueryStruct) -> None:
+        """ Add penalties to tokens that depend on presence of other token.
+        """
+        for _, node, tlist in query.iter_token_lists():
+            if tlist.ttype == qmod.TokenType.POSTCODE:
+                for repl in node.starting:
+                    if repl.end == tlist.end and repl.ttype != qmod.TokenType.POSTCODE \
+                       and (repl.ttype != qmod.TokenType.HOUSENUMBER
+                            or len(tlist.tokens[0].lookup_word) > 4):
+                        repl.add_penalty(0.39)
+            elif tlist.ttype == qmod.TokenType.HOUSENUMBER \
+                 and len(tlist.tokens[0].lookup_word) <= 3:
+                if any(c.isdigit() for c in tlist.tokens[0].lookup_word):
+                    for repl in node.starting:
+                        if repl.end == tlist.end and repl.ttype != qmod.TokenType.HOUSENUMBER:
+                            repl.add_penalty(0.5 - tlist.tokens[0].penalty)
+
+
+
+def _dump_word_tokens(query: qmod.QueryStruct) -> Iterator[List[Any]]:
+    yield ['type', 'token', 'word_token', 'lookup_word', 'penalty', 'count', 'info']
+    for node in query.nodes:
+        for tlist in node.starting:
+            for token in tlist.tokens:
+                t = cast(LegacyToken, token)
+                yield [tlist.ttype.name, t.token, t.word_token or '',
+                       t.lookup_word or '', t.penalty, t.count, t.info]
+
+
+async def create_query_analyzer(conn: SearchConnection) -> AbstractQueryAnalyzer:
+    """ Create and set up a new query analyzer for a database based
+        on the ICU tokenizer.
+    """
+    out = LegacyQueryAnalyzer(conn)
+    await out.setup()
+
+    return out

nominatim/api/search/query.py

@@ -0,0 +1,296 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Datastructures for a tokenized query.
+"""
+from typing import List, Tuple, Optional, Iterator
+from abc import ABC, abstractmethod
+import dataclasses
+import enum
+
+class BreakType(enum.Enum):
+    """ Type of break between tokens.
+    """
+    START = '<'
+    """ Begin of the query. """
+    END = '>'
+    """ End of the query. """
+    PHRASE = ','
+    """ Break between two phrases. """
+    WORD = ' '
+    """ Break between words. """
+    PART = '-'
+    """ Break inside a word, for example a hyphen or apostrophe. """
+    TOKEN = '`'
+    """ Break created as a result of tokenization.
+        This may happen in languages without spaces between words.
+    """
+
+
+class TokenType(enum.Enum):
+    """ Type of token.
+    """
+    WORD = enum.auto()
+    """ Full name of a place. """
+    PARTIAL = enum.auto()
+    """ Word term without breaks, does not necessarily represent a full name. """
+    HOUSENUMBER = enum.auto()
+    """ Housenumber term. """
+    POSTCODE = enum.auto()
+    """ Postal code term. """
+    COUNTRY = enum.auto()
+    """ Country name or reference. """
+    QUALIFIER = enum.auto()
+    """ Special term used together with name (e.g. _Hotel_ Bellevue). """
+    NEAR_ITEM = enum.auto()
+    """ Special term used as searchable object(e.g. supermarket in ...). """
+
+
+class PhraseType(enum.Enum):
+    """ Designation of a phrase.
+    """
+    NONE = 0
+    """ No specific designation (i.e. source is free-form query). """
+    AMENITY = enum.auto()
+    """ Contains name or type of a POI. """
+    STREET = enum.auto()
+    """ Contains a street name optionally with a housenumber. """
+    CITY = enum.auto()
+    """ Contains the postal city. """
+    COUNTY = enum.auto()
+    """ Contains the equivalent of a county. """
+    STATE = enum.auto()
+    """ Contains a state or province. """
+    POSTCODE = enum.auto()
+    """ Contains a postal code. """
+    COUNTRY = enum.auto()
+    """ Contains the country name or code. """
+
+    def compatible_with(self, ttype: TokenType,
+                        is_full_phrase: bool) -> bool:
+        """ Check if the given token type can be used with the phrase type.
+        """
+        if self == PhraseType.NONE:
+            return not is_full_phrase or ttype != TokenType.QUALIFIER
+        if self == PhraseType.AMENITY:
+            return ttype in (TokenType.WORD, TokenType.PARTIAL)\
+                   or (is_full_phrase and ttype == TokenType.NEAR_ITEM)\
+                   or (not is_full_phrase and ttype == TokenType.QUALIFIER)
+        if self == PhraseType.STREET:
+            return ttype in (TokenType.WORD, TokenType.PARTIAL, TokenType.HOUSENUMBER)
+        if self == PhraseType.POSTCODE:
+            return ttype == TokenType.POSTCODE
+        if self == PhraseType.COUNTRY:
+            return ttype == TokenType.COUNTRY
+
+        return ttype in (TokenType.WORD, TokenType.PARTIAL)
+
+
+@dataclasses.dataclass
+class Token(ABC):
+    """ Base type for tokens.
+        Specific query analyzers must implement the concrete token class.
+    """
+
+    penalty: float
+    token: int
+    count: int
+    lookup_word: str
+    is_indexed: bool
+
+
+    @abstractmethod
+    def get_category(self) -> Tuple[str, str]:
+        """ Return the category restriction for qualifier terms and
+            category objects.
+        """
+
+@dataclasses.dataclass
+class TokenRange:
+    """ Indexes of query nodes over which a token spans.
+    """
+    start: int
+    end: int
+
+    def __lt__(self, other: 'TokenRange') -> bool:
+        return self.end <= other.start
+
+
+    def __le__(self, other: 'TokenRange') -> bool:
+        return NotImplemented
+
+
+    def __gt__(self, other: 'TokenRange') -> bool:
+        return self.start >= other.end
+
+
+    def __ge__(self, other: 'TokenRange') -> bool:
+        return NotImplemented
+
+
+    def replace_start(self, new_start: int) -> 'TokenRange':
+        """ Return a new token range with the new start.
+        """
+        return TokenRange(new_start, self.end)
+
+
+    def replace_end(self, new_end: int) -> 'TokenRange':
+        """ Return a new token range with the new end.
+        """
+        return TokenRange(self.start, new_end)
+
+
+    def split(self, index: int) -> Tuple['TokenRange', 'TokenRange']:
+        """ Split the span into two spans at the given index.
+            The index must be within the span.
+        """
+        return self.replace_end(index), self.replace_start(index)
+
+
+@dataclasses.dataclass
+class TokenList:
+    """ List of all tokens of a given type going from one breakpoint to another.
+    """
+    end: int
+    ttype: TokenType
+    tokens: List[Token]
+
+
+    def add_penalty(self, penalty: float) -> None:
+        """ Add the given penalty to all tokens in the list.
+        """
+        for token in self.tokens:
+            token.penalty += penalty
+
+
+@dataclasses.dataclass
+class QueryNode:
+    """ A node of the query representing a break between terms.
+    """
+    btype: BreakType
+    ptype: PhraseType
+    starting: List[TokenList] = dataclasses.field(default_factory=list)
+
+    def has_tokens(self, end: int, *ttypes: TokenType) -> bool:
+        """ Check if there are tokens of the given types ending at the
+            given node.
+        """
+        return any(tl.end == end and tl.ttype in ttypes for tl in self.starting)
+
+
+    def get_tokens(self, end: int, ttype: TokenType) -> Optional[List[Token]]:
+        """ Get the list of tokens of the given type starting at this node
+            and ending at the node 'end'. Returns 'None' if no such
+            tokens exist.
+        """
+        for tlist in self.starting:
+            if tlist.end == end and tlist.ttype == ttype:
+                return tlist.tokens
+        return None
+
+
+@dataclasses.dataclass
+class Phrase:
+    """ A normalized query part. Phrases may be typed which means that
+        they then represent a specific part of the address.
+    """
+    ptype: PhraseType
+    text: str
+
+
+class QueryStruct:
+    """ A tokenized search query together with the normalized source
+        from which the tokens have been parsed.
+
+        The query contains a list of nodes that represent the breaks
+        between words. Tokens span between nodes, which don't necessarily
+        need to be direct neighbours. Thus the query is represented as a
+        directed acyclic graph.
+
+        When created, a query contains a single node: the start of the
+        query. Further nodes can be added by appending to 'nodes'.
+    """
+
+    def __init__(self, source: List[Phrase]) -> None:
+        self.source = source
+        self.nodes: List[QueryNode] = \
+            [QueryNode(BreakType.START, source[0].ptype if source else PhraseType.NONE)]
+
+
+    def num_token_slots(self) -> int:
+        """ Return the length of the query in vertice steps.
+        """
+        return len(self.nodes) - 1
+
+
+    def add_node(self, btype: BreakType, ptype: PhraseType) -> None:
+        """ Append a new break node with the given break type.
+            The phrase type denotes the type for any tokens starting
+            at the node.
+        """
+        self.nodes.append(QueryNode(btype, ptype))
+
+
+    def add_token(self, trange: TokenRange, ttype: TokenType, token: Token) -> None:
+        """ Add a token to the query. 'start' and 'end' are the indexes of the
+            nodes from which to which the token spans. The indexes must exist
+            and are expected to be in the same phrase.
+            'ttype' denotes the type of the token and 'token' the token to
+            be inserted.
+
+            If the token type is not compatible with the phrase it should
+            be added to, then the token is silently dropped.
+        """
+        snode = self.nodes[trange.start]
+        full_phrase = snode.btype in (BreakType.START, BreakType.PHRASE)\
+                      and self.nodes[trange.end].btype in (BreakType.PHRASE, BreakType.END)
+        if snode.ptype.compatible_with(ttype, full_phrase):
+            tlist = snode.get_tokens(trange.end, ttype)
+            if tlist is None:
+                snode.starting.append(TokenList(trange.end, ttype, [token]))
+            else:
+                tlist.append(token)
+
+
+    def get_tokens(self, trange: TokenRange, ttype: TokenType) -> List[Token]:
+        """ Get the list of tokens of a given type, spanning the given
+            nodes. The nodes must exist. If no tokens exist, an
+            empty list is returned.
+        """
+        return self.nodes[trange.start].get_tokens(trange.end, ttype) or []
+
+
+    def get_partials_list(self, trange: TokenRange) -> List[Token]:
+        """ Create a list of partial tokens between the given nodes.
+            The list is composed of the first token of type PARTIAL
+            going to the subsequent node. Such PARTIAL tokens are
+            assumed to exist.
+        """
+        return [next(iter(self.get_tokens(TokenRange(i, i+1), TokenType.PARTIAL)))
+                          for i in range(trange.start, trange.end)]
+
+
+    def iter_token_lists(self) -> Iterator[Tuple[int, QueryNode, TokenList]]:
+        """ Iterator over all token lists in the query.
+        """
+        for i, node in enumerate(self.nodes):
+            for tlist in node.starting:
+                yield i, node, tlist
+
+
+    def find_lookup_word_by_id(self, token: int) -> str:
+        """ Find the first token with the given token ID and return
+            its lookup word. Returns 'None' if no such token exists.
+            The function is very slow and must only be used for
+            debugging.
+        """
+        for node in self.nodes:
+            for tlist in node.starting:
+                for t in tlist.tokens:
+                    if t.token == token:
+                        return f"[{tlist.ttype.name[0]}]{t.lookup_word}"
+        return 'None'

nominatim/api/search/query_analyzer_factory.py

@@ -0,0 +1,54 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Factory for creating a query analyzer for the configured tokenizer.
+"""
+from typing import List, cast, TYPE_CHECKING
+from abc import ABC, abstractmethod
+from pathlib import Path
+import importlib
+
+from nominatim.api.logging import log
+from nominatim.api.connection import SearchConnection
+
+if TYPE_CHECKING:
+    from nominatim.api.search.query import Phrase, QueryStruct
+
+class AbstractQueryAnalyzer(ABC):
+    """ Class for analysing incoming queries.
+
+        Query analyzers are tied to the tokenizer used on import.
+    """
+
+    @abstractmethod
+    async def analyze_query(self, phrases: List['Phrase']) -> 'QueryStruct':
+        """ Analyze the given phrases and return the tokenized query.
+        """
+
+
+    @abstractmethod
+    def normalize_text(self, text: str) -> str:
+        """ Bring the given text into a normalized form. That is the
+            standardized form search will work with. All information removed
+            at this stage is inevitably lost.
+        """
+
+
+
+async def make_query_analyzer(conn: SearchConnection) -> AbstractQueryAnalyzer:
+    """ Create a query analyzer for the tokenizer used by the database.
+    """
+    name = await conn.get_property('tokenizer')
+
+    src_file = Path(__file__).parent / f'{name}_tokenizer.py'
+    if not src_file.is_file():
+        log().comment(f"No tokenizer named '{name}' available. Database not set up properly.")
+        raise RuntimeError('Tokenizer not found')
+
+    module = importlib.import_module(f'nominatim.api.search.{name}_tokenizer')
+
+    return cast(AbstractQueryAnalyzer, await module.create_query_analyzer(conn))

nominatim/api/search/token_assignment.py

@@ -0,0 +1,421 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Create query interpretations where each vertice in the query is assigned
+a specific function (expressed as a token type).
+"""
+from typing import Optional, List, Iterator
+import dataclasses
+
+import nominatim.api.search.query as qmod
+from nominatim.api.logging import log
+
+# pylint: disable=too-many-return-statements,too-many-branches
+
+@dataclasses.dataclass
+class TypedRange:
+    """ A token range for a specific type of tokens.
+    """
+    ttype: qmod.TokenType
+    trange: qmod.TokenRange
+
+
+PENALTY_TOKENCHANGE = {
+    qmod.BreakType.START: 0.0,
+    qmod.BreakType.END: 0.0,
+    qmod.BreakType.PHRASE: 0.0,
+    qmod.BreakType.WORD: 0.1,
+    qmod.BreakType.PART: 0.2,
+    qmod.BreakType.TOKEN: 0.4
+}
+
+TypedRangeSeq = List[TypedRange]
+
+@dataclasses.dataclass
+class TokenAssignment: # pylint: disable=too-many-instance-attributes
+    """ Representation of a possible assignment of token types
+        to the tokens in a tokenized query.
+    """
+    penalty: float = 0.0
+    name: Optional[qmod.TokenRange] = None
+    address: List[qmod.TokenRange] = dataclasses.field(default_factory=list)
+    housenumber: Optional[qmod.TokenRange] = None
+    postcode: Optional[qmod.TokenRange] = None
+    country: Optional[qmod.TokenRange] = None
+    near_item: Optional[qmod.TokenRange] = None
+    qualifier: Optional[qmod.TokenRange] = None
+
+
+    @staticmethod
+    def from_ranges(ranges: TypedRangeSeq) -> 'TokenAssignment':
+        """ Create a new token assignment from a sequence of typed spans.
+        """
+        out = TokenAssignment()
+        for token in ranges:
+            if token.ttype == qmod.TokenType.PARTIAL:
+                out.address.append(token.trange)
+            elif token.ttype == qmod.TokenType.HOUSENUMBER:
+                out.housenumber = token.trange
+            elif token.ttype == qmod.TokenType.POSTCODE:
+                out.postcode = token.trange
+            elif token.ttype == qmod.TokenType.COUNTRY:
+                out.country = token.trange
+            elif token.ttype == qmod.TokenType.NEAR_ITEM:
+                out.near_item = token.trange
+            elif token.ttype == qmod.TokenType.QUALIFIER:
+                out.qualifier = token.trange
+        return out
+
+
+class _TokenSequence:
+    """ Working state used to put together the token assignments.
+
+        Represents an intermediate state while traversing the tokenized
+        query.
+    """
+    def __init__(self, seq: TypedRangeSeq,
+                 direction: int = 0, penalty: float = 0.0) -> None:
+        self.seq = seq
+        self.direction = direction
+        self.penalty = penalty
+
+
+    def __str__(self) -> str:
+        seq = ''.join(f'[{r.trange.start} - {r.trange.end}: {r.ttype.name}]' for r in self.seq)
+        return f'{seq} (dir: {self.direction}, penalty: {self.penalty})'
+
+
+    @property
+    def end_pos(self) -> int:
+        """ Return the index of the global end of the current sequence.
+        """
+        return self.seq[-1].trange.end if self.seq else 0
+
+
+    def has_types(self, *ttypes: qmod.TokenType) -> bool:
+        """ Check if the current sequence contains any typed ranges of
+            the given types.
+        """
+        return any(s.ttype in ttypes for s in self.seq)
+
+
+    def is_final(self) -> bool:
+        """ Return true when the sequence cannot be extended by any
+            form of token anymore.
+        """
+        # Country and category must be the final term for left-to-right
+        return len(self.seq) > 1 and \
+               self.seq[-1].ttype in (qmod.TokenType.COUNTRY, qmod.TokenType.NEAR_ITEM)
+
+
+    def appendable(self, ttype: qmod.TokenType) -> Optional[int]:
+        """ Check if the give token type is appendable to the existing sequence.
+
+            Returns None if the token type is not appendable, otherwise the
+            new direction of the sequence after adding such a type. The
+            token is not added.
+        """
+        if ttype == qmod.TokenType.WORD:
+            return None
+
+        if not self.seq:
+            # Append unconditionally to the empty list
+            if ttype == qmod.TokenType.COUNTRY:
+                return -1
+            if ttype in (qmod.TokenType.HOUSENUMBER, qmod.TokenType.QUALIFIER):
+                return 1
+            return self.direction
+
+        # Name tokens are always acceptable and don't change direction
+        if ttype == qmod.TokenType.PARTIAL:
+            # qualifiers cannot appear in the middle of the query. They need
+            # to be near the next phrase.
+            if self.direction == -1 \
+               and any(t.ttype == qmod.TokenType.QUALIFIER for t in self.seq[:-1]):
+                return None
+            return self.direction
+
+        # Other tokens may only appear once
+        if self.has_types(ttype):
+            return None
+
+        if ttype == qmod.TokenType.HOUSENUMBER:
+            if self.direction == 1:
+                if len(self.seq) == 1 and self.seq[0].ttype == qmod.TokenType.QUALIFIER:
+                    return None
+                if len(self.seq) > 2 \
+                   or self.has_types(qmod.TokenType.POSTCODE, qmod.TokenType.COUNTRY):
+                    return None # direction left-to-right: housenumber must come before anything
+            elif self.direction == -1 \
+                 or self.has_types(qmod.TokenType.POSTCODE, qmod.TokenType.COUNTRY):
+                return -1 # force direction right-to-left if after other terms
+
+            return self.direction
+
+        if ttype == qmod.TokenType.POSTCODE:
+            if self.direction == -1:
+                if self.has_types(qmod.TokenType.HOUSENUMBER, qmod.TokenType.QUALIFIER):
+                    return None
+                return -1
+            if self.direction == 1:
+                return None if self.has_types(qmod.TokenType.COUNTRY) else 1
+            if self.has_types(qmod.TokenType.HOUSENUMBER, qmod.TokenType.QUALIFIER):
+                return 1
+            return self.direction
+
+        if ttype == qmod.TokenType.COUNTRY:
+            return None if self.direction == -1 else 1
+
+        if ttype == qmod.TokenType.NEAR_ITEM:
+            return self.direction
+
+        if ttype == qmod.TokenType.QUALIFIER:
+            if self.direction == 1:
+                if (len(self.seq) == 1
+                    and self.seq[0].ttype in (qmod.TokenType.PARTIAL, qmod.TokenType.NEAR_ITEM)) \
+                   or (len(self.seq) == 2
+                       and self.seq[0].ttype == qmod.TokenType.NEAR_ITEM
+                       and self.seq[1].ttype == qmod.TokenType.PARTIAL):
+                    return 1
+                return None
+            if self.direction == -1:
+                return -1
+
+            tempseq = self.seq[1:] if self.seq[0].ttype == qmod.TokenType.NEAR_ITEM else self.seq
+            if len(tempseq) == 0:
+                return 1
+            if len(tempseq) == 1 and self.seq[0].ttype == qmod.TokenType.HOUSENUMBER:
+                return None
+            if len(tempseq) > 1 or self.has_types(qmod.TokenType.POSTCODE, qmod.TokenType.COUNTRY):
+                return -1
+            return 0
+
+        return None
+
+
+    def advance(self, ttype: qmod.TokenType, end_pos: int,
+                btype: qmod.BreakType) -> Optional['_TokenSequence']:
+        """ Return a new token sequence state with the given token type
+            extended.
+        """
+        newdir = self.appendable(ttype)
+        if newdir is None:
+            return None
+
+        if not self.seq:
+            newseq = [TypedRange(ttype, qmod.TokenRange(0, end_pos))]
+            new_penalty = 0.0
+        else:
+            last = self.seq[-1]
+            if btype != qmod.BreakType.PHRASE and last.ttype == ttype:
+                # extend the existing range
+                newseq = self.seq[:-1] + [TypedRange(ttype, last.trange.replace_end(end_pos))]
+                new_penalty = 0.0
+            else:
+                # start a new range
+                newseq = list(self.seq) + [TypedRange(ttype,
+                                                      qmod.TokenRange(last.trange.end, end_pos))]
+                new_penalty = PENALTY_TOKENCHANGE[btype]
+
+        return _TokenSequence(newseq, newdir, self.penalty + new_penalty)
+
+
+    def _adapt_penalty_from_priors(self, priors: int, new_dir: int) -> bool:
+        if priors == 2:
+            self.penalty += 1.0
+        elif priors > 2:
+            if self.direction == 0:
+                self.direction = new_dir
+            else:
+                return False
+
+        return True
+
+
+    def recheck_sequence(self) -> bool:
+        """ Check that the sequence is a fully valid token assignment
+            and adapt direction and penalties further if necessary.
+
+            This function catches some impossible assignments that need
+            forward context and can therefore not be excluded when building
+            the assignment.
+        """
+        # housenumbers may not be further than 2 words from the beginning.
+        # If there are two words in front, give it a penalty.
+        hnrpos = next((i for i, tr in enumerate(self.seq)
+                       if tr.ttype == qmod.TokenType.HOUSENUMBER),
+                      None)
+        if hnrpos is not None:
+            if self.direction != -1:
+                priors = sum(1 for t in self.seq[:hnrpos] if t.ttype == qmod.TokenType.PARTIAL)
+                if not self._adapt_penalty_from_priors(priors, -1):
+                    return False
+            if self.direction != 1:
+                priors = sum(1 for t in self.seq[hnrpos+1:] if t.ttype == qmod.TokenType.PARTIAL)
+                if not self._adapt_penalty_from_priors(priors, 1):
+                    return False
+            if any(t.ttype == qmod.TokenType.NEAR_ITEM for t in self.seq):
+                self.penalty += 1.0
+
+        return True
+
+
+    def _get_assignments_postcode(self, base: TokenAssignment,
+                                  query_len: int)  -> Iterator[TokenAssignment]:
+        """ Yield possible assignments of Postcode searches with an
+            address component.
+        """
+        assert base.postcode is not None
+
+        if (base.postcode.start == 0 and self.direction != -1)\
+           or (base.postcode.end == query_len and self.direction != 1):
+            log().comment('postcode search')
+            # <address>,<postcode> should give preference to address search
+            if base.postcode.start == 0:
+                penalty = self.penalty
+                self.direction = -1 # name searches are only possible backwards
+            else:
+                penalty = self.penalty + 0.1
+                self.direction = 1 # name searches are only possible forwards
+            yield dataclasses.replace(base, penalty=penalty)
+
+
+    def _get_assignments_address_forward(self, base: TokenAssignment,
+                                         query: qmod.QueryStruct) -> Iterator[TokenAssignment]:
+        """ Yield possible assignments of address searches with
+            left-to-right reading.
+        """
+        first = base.address[0]
+
+        log().comment('first word = name')
+        yield dataclasses.replace(base, penalty=self.penalty,
+                                  name=first, address=base.address[1:])
+
+        # To paraphrase:
+        #  * if another name term comes after the first one and before the
+        #    housenumber
+        #  * a qualifier comes after the name
+        #  * the containing phrase is strictly typed
+        if (base.housenumber and first.end < base.housenumber.start)\
+           or (base.qualifier and base.qualifier > first)\
+           or (query.nodes[first.start].ptype != qmod.PhraseType.NONE):
+            return
+
+        penalty = self.penalty
+
+        # Penalty for:
+        #  * <name>, <street>, <housenumber> , ...
+        #  * queries that are comma-separated
+        if (base.housenumber and base.housenumber > first) or len(query.source) > 1:
+            penalty += 0.25
+
+        for i in range(first.start + 1, first.end):
+            name, addr = first.split(i)
+            log().comment(f'split first word = name ({i - first.start})')
+            yield dataclasses.replace(base, name=name, address=[addr] + base.address[1:],
+                                      penalty=penalty + PENALTY_TOKENCHANGE[query.nodes[i].btype])
+
+
+    def _get_assignments_address_backward(self, base: TokenAssignment,
+                                          query: qmod.QueryStruct) -> Iterator[TokenAssignment]:
+        """ Yield possible assignments of address searches with
+            right-to-left reading.
+        """
+        last = base.address[-1]
+
+        if self.direction == -1 or len(base.address) > 1:
+            log().comment('last word = name')
+            yield dataclasses.replace(base, penalty=self.penalty,
+                                      name=last, address=base.address[:-1])
+
+        # To paraphrase:
+        #  * if another name term comes before the last one and after the
+        #    housenumber
+        #  * a qualifier comes before the name
+        #  * the containing phrase is strictly typed
+        if (base.housenumber and last.start > base.housenumber.end)\
+           or (base.qualifier and base.qualifier < last)\
+           or (query.nodes[last.start].ptype != qmod.PhraseType.NONE):
+            return
+
+        penalty = self.penalty
+        if base.housenumber and base.housenumber < last:
+            penalty += 0.4
+        if len(query.source) > 1:
+            penalty += 0.25
+
+        for i in range(last.start + 1, last.end):
+            addr, name = last.split(i)
+            log().comment(f'split last word = name ({i - last.start})')
+            yield dataclasses.replace(base, name=name, address=base.address[:-1] + [addr],
+                                      penalty=penalty + PENALTY_TOKENCHANGE[query.nodes[i].btype])
+
+
+    def get_assignments(self, query: qmod.QueryStruct) -> Iterator[TokenAssignment]:
+        """ Yield possible assignments for the current sequence.
+
+            This function splits up general name assignments into name
+            and address and yields all possible variants of that.
+        """
+        base = TokenAssignment.from_ranges(self.seq)
+
+        num_addr_tokens = sum(t.end - t.start for t in base.address)
+        if num_addr_tokens > 50:
+            return
+
+        # Postcode search (postcode-only search is covered in next case)
+        if base.postcode is not None and base.address:
+            yield from self._get_assignments_postcode(base, query.num_token_slots())
+
+        # Postcode or country-only search
+        if not base.address:
+            if not base.housenumber and (base.postcode or base.country or base.near_item):
+                log().comment('postcode/country search')
+                yield dataclasses.replace(base, penalty=self.penalty)
+        else:
+            # <postcode>,<address> should give preference to postcode search
+            if base.postcode and base.postcode.start == 0:
+                self.penalty += 0.1
+
+            # Right-to-left reading of the address
+            if self.direction != -1:
+                yield from self._get_assignments_address_forward(base, query)
+
+            # Left-to-right reading of the address
+            if self.direction != 1:
+                yield from self._get_assignments_address_backward(base, query)
+
+            # variant for special housenumber searches
+            if base.housenumber and not base.qualifier:
+                yield dataclasses.replace(base, penalty=self.penalty)
+
+
+def yield_token_assignments(query: qmod.QueryStruct) -> Iterator[TokenAssignment]:
+    """ Return possible word type assignments to word positions.
+
+        The assignments are computed from the concrete tokens listed
+        in the tokenized query.
+
+        The result includes the penalty for transitions from one word type to
+        another. It does not include penalties for transitions within a
+        type.
+    """
+    todo = [_TokenSequence([], direction=0 if query.source[0].ptype == qmod.PhraseType.NONE else 1)]
+
+    while todo:
+        state = todo.pop()
+        node = query.nodes[state.end_pos]
+
+        for tlist in node.starting:
+            newstate = state.advance(tlist.ttype, tlist.end, node.btype)
+            if newstate is not None:
+                if newstate.end_pos == query.num_token_slots():
+                    if newstate.recheck_sequence():
+                        log().var_dump('Assignment', newstate)
+                        yield from newstate.get_assignments(query)
+                elif not newstate.is_final():
+                    todo.append(newstate)

nominatim/api/status.py

@@ -0,0 +1,52 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Classes and function related to status call.
+"""
+from typing import Optional
+import datetime as dt
+import dataclasses
+
+import sqlalchemy as sa
+
+from nominatim.api.connection import SearchConnection
+from nominatim import version
+
+@dataclasses.dataclass
+class StatusResult:
+    """ Result of a call to the status API.
+    """
+    status: int
+    message: str
+    software_version = version.NOMINATIM_VERSION
+    data_updated: Optional[dt.datetime] = None
+    database_version: Optional[version.NominatimVersion] = None
+
+
+async def get_status(conn: SearchConnection) -> StatusResult:
+    """ Execute a status API call.
+    """
+    status = StatusResult(0, 'OK')
+
+    # Last update date
+    sql = sa.select(conn.t.import_status.c.lastimportdate).limit(1)
+    status.data_updated = await conn.scalar(sql)
+
+    if status.data_updated is not None:
+        if status.data_updated.tzinfo is None:
+            status.data_updated = status.data_updated.replace(tzinfo=dt.timezone.utc)
+        else:
+            status.data_updated = status.data_updated.astimezone(dt.timezone.utc)
+
+    # Database version
+    try:
+        verstr = await conn.get_property('database_version')
+        status.database_version = version.parse_version(verstr)
+    except ValueError:
+        pass
+
+    return status

nominatim/api/types.py

@@ -0,0 +1,550 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Complex datatypes used by the Nominatim API.
+"""
+from typing import Optional, Union, Tuple, NamedTuple, TypeVar, Type, Dict, \
+                   Any, List, Sequence
+from collections import abc
+import dataclasses
+import enum
+import math
+from struct import unpack
+from binascii import unhexlify
+
+from nominatim.errors import UsageError
+from nominatim.api.localization import Locales
+
+# pylint: disable=no-member,too-many-boolean-expressions,too-many-instance-attributes
+
+@dataclasses.dataclass
+class PlaceID:
+    """ Reference a place by Nominatim's internal ID.
+
+        A PlaceID may reference place from the main table placex, from
+        the interpolation tables or the postcode tables. Place IDs are not
+        stable between installations. You may use this type theefore only
+        with place IDs obtained from the same database.
+    """
+    place_id: int
+    """
+    The internal ID of the place to reference.
+    """
+
+
+@dataclasses.dataclass
+class OsmID:
+    """ Reference a place by its OSM ID and potentially the basic category.
+
+        The OSM ID may refer to places in the main table placex and OSM
+        interpolation lines.
+    """
+    osm_type: str
+    """ OSM type of the object. Must be one of `N`(node), `W`(way) or
+        `R`(relation).
+    """
+    osm_id: int
+    """ The OSM ID of the object.
+    """
+    osm_class: Optional[str] = None
+    """ The same OSM object may appear multiple times in the database under
+        different categories. The optional class parameter allows to distinguish
+        the different categories and corresponds to the key part of the category.
+        If there are multiple objects in the database and `osm_class` is
+        left out, then one of the objects is returned at random.
+    """
+
+    def __post_init__(self) -> None:
+        if self.osm_type not in ('N', 'W', 'R'):
+            raise ValueError(f"Illegal OSM type '{self.osm_type}'. Must be one of N, W, R.")
+
+
+PlaceRef = Union[PlaceID, OsmID]
+
+
+class Point(NamedTuple):
+    """ A geographic point in WGS84 projection.
+    """
+    x: float
+    y: float
+
+
+    @property
+    def lat(self) -> float:
+        """ Return the latitude of the point.
+        """
+        return self.y
+
+
+    @property
+    def lon(self) -> float:
+        """ Return the longitude of the point.
+        """
+        return self.x
+
+
+    def to_geojson(self) -> str:
+        """ Return the point in GeoJSON format.
+        """
+        return f'{{"type": "Point","coordinates": [{self.x}, {self.y}]}}'
+
+
+    @staticmethod
+    def from_wkb(wkb: Union[str, bytes]) -> 'Point':
+        """ Create a point from EWKB as returned from the database.
+        """
+        if isinstance(wkb, str):
+            wkb = unhexlify(wkb)
+        if len(wkb) != 25:
+            raise ValueError(f"Point wkb has unexpected length {len(wkb)}")
+        if wkb[0] == 0:
+            gtype, srid, x, y = unpack('>iidd', wkb[1:])
+        elif wkb[0] == 1:
+            gtype, srid, x, y = unpack('<iidd', wkb[1:])
+        else:
+            raise ValueError("WKB has unknown endian value.")
+
+        if gtype != 0x20000001:
+            raise ValueError("WKB must be a point geometry.")
+        if srid != 4326:
+            raise ValueError("Only WGS84 WKB supported.")
+
+        return Point(x, y)
+
+
+    @staticmethod
+    def from_param(inp: Any) -> 'Point':
+        """ Create a point from an input parameter. The parameter
+            may be given as a point, a string or a sequence of
+            strings or floats. Raises a UsageError if the format is
+            not correct.
+        """
+        if isinstance(inp, Point):
+            return inp
+
+        seq: Sequence[str]
+        if isinstance(inp, str):
+            seq = inp.split(',')
+        elif isinstance(inp, abc.Sequence):
+            seq = inp
+
+        if len(seq) != 2:
+            raise UsageError('Point parameter needs 2 coordinates.')
+        try:
+            x, y = filter(math.isfinite, map(float, seq))
+        except ValueError as exc:
+            raise UsageError('Point parameter needs to be numbers.') from exc
+
+        if x < -180.0 or x > 180.0 or y < -90.0 or y > 90.0:
+            raise UsageError('Point coordinates invalid.')
+
+        return Point(x, y)
+
+
+    def to_wkt(self) -> str:
+        """ Return the WKT representation of the point.
+        """
+        return f'POINT({self.x} {self.y})'
+
+
+
+AnyPoint = Union[Point, Tuple[float, float]]
+
+WKB_BBOX_HEADER_LE = b'\x01\x03\x00\x00\x20\xE6\x10\x00\x00\x01\x00\x00\x00\x05\x00\x00\x00'
+WKB_BBOX_HEADER_BE = b'\x00\x20\x00\x00\x03\x00\x00\x10\xe6\x00\x00\x00\x01\x00\x00\x00\x05'
+
+class Bbox:
+    """ A bounding box in WGS84 projection.
+
+        The coordinates are available as an array in the 'coord'
+        property in the order (minx, miny, maxx, maxy).
+    """
+    def __init__(self, minx: float, miny: float, maxx: float, maxy: float) -> None:
+        """ Create a new bounding box with the given coordinates in WGS84
+            projection.
+        """
+        self.coords = (minx, miny, maxx, maxy)
+
+
+    @property
+    def minlat(self) -> float:
+        """ Southern-most latitude, corresponding to the minimum y coordinate.
+        """
+        return self.coords[1]
+
+
+    @property
+    def maxlat(self) -> float:
+        """ Northern-most latitude, corresponding to the maximum y coordinate.
+        """
+        return self.coords[3]
+
+
+    @property
+    def minlon(self) -> float:
+        """ Western-most longitude, corresponding to the minimum x coordinate.
+        """
+        return self.coords[0]
+
+
+    @property
+    def maxlon(self) -> float:
+        """ Eastern-most longitude, corresponding to the maximum x coordinate.
+        """
+        return self.coords[2]
+
+
+    @property
+    def area(self) -> float:
+        """ Return the area of the box in WGS84.
+        """
+        return (self.coords[2] - self.coords[0]) * (self.coords[3] - self.coords[1])
+
+
+    def contains(self, pt: Point) -> bool:
+        """ Check if the point is inside or on the boundary of the box.
+        """
+        return self.coords[0] <= pt[0] and self.coords[1] <= pt[1]\
+               and self.coords[2] >= pt[0] and self.coords[3] >= pt[1]
+
+
+    def to_wkt(self) -> str:
+        """ Return the WKT representation of the Bbox. This
+            is a simple polygon with four points.
+        """
+        return 'POLYGON(({0} {1},{0} {3},{2} {3},{2} {1},{0} {1}))'\
+                  .format(*self.coords) # pylint: disable=consider-using-f-string
+
+
+    @staticmethod
+    def from_wkb(wkb: Union[None, str, bytes]) -> 'Optional[Bbox]':
+        """ Create a Bbox from a bounding box polygon as returned by
+            the database. Returns `None` if the input value is None.
+        """
+        if wkb is None:
+            return None
+
+        if isinstance(wkb, str):
+            wkb = unhexlify(wkb)
+
+        if len(wkb) != 97:
+            raise ValueError("WKB must be a bounding box polygon")
+        if wkb.startswith(WKB_BBOX_HEADER_LE):
+            x1, y1, _, _, x2, y2 = unpack('<dddddd', wkb[17:65])
+        elif wkb.startswith(WKB_BBOX_HEADER_BE):
+            x1, y1, _, _, x2, y2 = unpack('>dddddd', wkb[17:65])
+        else:
+            raise ValueError("WKB has wrong header")
+
+        return Bbox(min(x1, x2), min(y1, y2), max(x1, x2), max(y1, y2))
+
+
+    @staticmethod
+    def from_point(pt: Point, buffer: float) -> 'Bbox':
+        """ Return a Bbox around the point with the buffer added to all sides.
+        """
+        return Bbox(pt[0] - buffer, pt[1] - buffer,
+                    pt[0] + buffer, pt[1] + buffer)
+
+
+    @staticmethod
+    def from_param(inp: Any) -> 'Bbox':
+        """ Return a Bbox from an input parameter. The box may be
+            given as a Bbox, a string or a list or strings or integer.
+            Raises a UsageError if the format is incorrect.
+        """
+        if isinstance(inp, Bbox):
+            return inp
+
+        seq: Sequence[str]
+        if isinstance(inp, str):
+            seq = inp.split(',')
+        elif isinstance(inp, abc.Sequence):
+            seq = inp
+
+        if len(seq) != 4:
+            raise UsageError('Bounding box parameter needs 4 coordinates.')
+        try:
+            x1, y1, x2, y2 = filter(math.isfinite, map(float, seq))
+        except ValueError as exc:
+            raise UsageError('Bounding box parameter needs to be numbers.') from exc
+
+        x1 = min(180, max(-180, x1))
+        x2 = min(180, max(-180, x2))
+        y1 = min(90, max(-90, y1))
+        y2 = min(90, max(-90, y2))
+
+        if x1 == x2 or y1 == y2:
+            raise UsageError('Bounding box with invalid parameters.')
+
+        return Bbox(min(x1, x2), min(y1, y2), max(x1, x2), max(y1, y2))
+
+
+class GeometryFormat(enum.Flag):
+    """ All search functions support returning the full geometry of a place in
+        various formats. The internal geometry is converted by PostGIS to
+        the desired format and then returned as a string. It is possible to
+        request multiple formats at the same time.
+    """
+    NONE = 0
+    """ No geometry requested. Alias for a empty flag.
+    """
+    GEOJSON = enum.auto()
+    """
+    [GeoJSON](https://geojson.org/) format
+    """
+    KML = enum.auto()
+    """
+    [KML](https://en.wikipedia.org/wiki/Keyhole_Markup_Language) format
+    """
+    SVG = enum.auto()
+    """
+    [SVG](http://www.w3.org/TR/SVG/paths.html) format
+    """
+    TEXT = enum.auto()
+    """
+    [WKT](https://en.wikipedia.org/wiki/Well-known_text_representation_of_geometry) format
+    """
+
+
+class DataLayer(enum.Flag):
+    """ The `DataLayer` flag type defines the layers that can be selected
+        for reverse and forward search.
+    """
+    ADDRESS = enum.auto()
+    """ The address layer contains all places relevant for addresses:
+        fully qualified addresses with a house number (or a house name equivalent,
+        for some addresses) and places that can be part of an address like
+        roads, cities, states.
+    """
+    POI = enum.auto()
+    """ Layer for points of interest like shops, restaurants but also
+        recycling bins or postboxes.
+    """
+    RAILWAY = enum.auto()
+    """ Layer with railway features including tracks and other infrastructure.
+        Note that in Nominatim's standard configuration, only very few railway
+        features are imported into the database. Thus a custom configuration
+        is required to make full use of this layer.
+    """
+    NATURAL = enum.auto()
+    """ Layer with natural features like rivers, lakes and mountains.
+    """
+    MANMADE = enum.auto()
+    """ Layer with other human-made features and boundaries. This layer is
+        the catch-all and includes all features not covered by the other
+        layers. A typical example for this layer are national park boundaries.
+    """
+
+
+def format_country(cc: Any) -> List[str]:
+    """ Extract a list of country codes from the input which may be either
+        a string or list of strings. Filters out all values that are not
+        a two-letter string.
+    """
+    clist: Sequence[str]
+    if isinstance(cc, str):
+        clist = cc.split(',')
+    elif isinstance(cc, abc.Sequence):
+        clist = cc
+    else:
+        raise UsageError("Parameter 'country' needs to be a comma-separated list "
+                         "or a Python list of strings.")
+
+    return [cc.lower() for cc in clist if isinstance(cc, str) and len(cc) == 2]
+
+
+def format_excluded(ids: Any) -> List[int]:
+    """ Extract a list of place ids from the input which may be either
+        a string or a list of strings or ints. Ignores empty value but
+        throws a UserError on anything that cannot be converted to int.
+    """
+    plist: Sequence[str]
+    if isinstance(ids, str):
+        plist = [s.strip() for s in ids.split(',')]
+    elif isinstance(ids, abc.Sequence):
+        plist = ids
+    else:
+        raise UsageError("Parameter 'excluded' needs to be a comma-separated list "
+                         "or a Python list of numbers.")
+    if not all(isinstance(i, int) or
+               (isinstance(i, str) and (not i or i.isdigit())) for i in plist):
+        raise UsageError("Parameter 'excluded' only takes place IDs.")
+
+    return [int(id) for id in plist if id] or [0]
+
+
+def format_categories(categories: List[Tuple[str, str]]) -> List[Tuple[str, str]]:
+    """ Extract a list of categories. Currently a noop.
+    """
+    return categories
+
+TParam = TypeVar('TParam', bound='LookupDetails') # pylint: disable=invalid-name
+
+@dataclasses.dataclass
+class LookupDetails:
+    """ Collection of parameters that define which kind of details are
+        returned with a lookup or details result.
+    """
+    geometry_output: GeometryFormat = GeometryFormat.NONE
+    """ Add the full geometry of the place to the result. Multiple
+        formats may be selected. Note that geometries can become quite large.
+    """
+    address_details: bool = False
+    """ Get detailed information on the places that make up the address
+        for the result.
+    """
+    linked_places: bool = False
+    """ Get detailed information on the places that link to the result.
+    """
+    parented_places: bool = False
+    """ Get detailed information on all places that this place is a parent
+        for, i.e. all places for which it provides the address details.
+        Only POI places can have parents.
+    """
+    keywords: bool = False
+    """ Add information about the search terms used for this place.
+    """
+    geometry_simplification: float = 0.0
+    """ Simplification factor for a geometry in degrees WGS. A factor of
+        0.0 means the original geometry is kept. The higher the value, the
+        more the geometry gets simplified.
+    """
+    locales: Locales = Locales()
+    """ Preferred languages for localization of results.
+    """
+
+    @classmethod
+    def from_kwargs(cls: Type[TParam], kwargs: Dict[str, Any]) -> TParam:
+        """ Load the data fields of the class from a dictionary.
+            Unknown entries in the dictionary are ignored, missing ones
+            get the default setting.
+
+            The function supports type checking and throws a UsageError
+            when the value does not fit.
+        """
+        def _check_field(v: Any, field: 'dataclasses.Field[Any]') -> Any:
+            if v is None:
+                return field.default_factory() \
+                       if field.default_factory != dataclasses.MISSING \
+                       else field.default
+            if field.metadata and 'transform' in field.metadata:
+                return field.metadata['transform'](v)
+            if not isinstance(v, field.type):
+                raise UsageError(f"Parameter '{field.name}' needs to be of {field.type!s}.")
+            return v
+
+        return cls(**{f.name: _check_field(kwargs[f.name], f)
+                      for f in dataclasses.fields(cls) if f.name in kwargs})
+
+
+@dataclasses.dataclass
+class ReverseDetails(LookupDetails):
+    """ Collection of parameters for the reverse call.
+    """
+    max_rank: int = dataclasses.field(default=30,
+                                      metadata={'transform': lambda v: max(0, min(v, 30))}
+                                     )
+    """ Highest address rank to return.
+    """
+    layers: DataLayer = DataLayer.ADDRESS | DataLayer.POI
+    """ Filter which kind of data to include.
+    """
+
+@dataclasses.dataclass
+class SearchDetails(LookupDetails):
+    """ Collection of parameters for the search call.
+    """
+    max_results: int = 10
+    """ Maximum number of results to be returned. The actual number of results
+        may be less.
+    """
+    min_rank: int = dataclasses.field(default=0,
+                                      metadata={'transform': lambda v: max(0, min(v, 30))}
+                                     )
+    """ Lowest address rank to return.
+    """
+    max_rank: int = dataclasses.field(default=30,
+                                      metadata={'transform': lambda v: max(0, min(v, 30))}
+                                     )
+    """ Highest address rank to return.
+    """
+    layers: Optional[DataLayer] = dataclasses.field(default=None,
+                                                    metadata={'transform': lambda r : r})
+    """ Filter which kind of data to include. When 'None' (the default) then
+        filtering by layers is disabled.
+    """
+    countries: List[str] = dataclasses.field(default_factory=list,
+                                             metadata={'transform': format_country})
+    """ Restrict search results to the given countries. An empty list (the
+        default) will disable this filter.
+    """
+    excluded: List[int] = dataclasses.field(default_factory=list,
+                                            metadata={'transform': format_excluded})
+    """ List of OSM objects to exclude from the results. Currently only
+        works when the internal place ID is given.
+        An empty list (the default) will disable this filter.
+    """
+    viewbox: Optional[Bbox] = dataclasses.field(default=None,
+                                                metadata={'transform': Bbox.from_param})
+    """ Focus the search on a given map area.
+    """
+    bounded_viewbox: bool = False
+    """ Use 'viewbox' as a filter and restrict results to places within the
+        given area.
+    """
+    near: Optional[Point] = dataclasses.field(default=None,
+                                              metadata={'transform': Point.from_param})
+    """ Order results by distance to the given point.
+    """
+    near_radius: Optional[float] = dataclasses.field(default=None,
+                                              metadata={'transform': lambda r : r})
+    """ Use near point as a filter and drop results outside the given
+        radius. Radius is given in degrees WSG84.
+    """
+    categories: List[Tuple[str, str]] = dataclasses.field(default_factory=list,
+                                                          metadata={'transform': format_categories})
+    """ Restrict search to places with one of the given class/type categories.
+        An empty list (the default) will disable this filter.
+    """
+    viewbox_x2: Optional[Bbox] = None
+
+    def __post_init__(self) -> None:
+        if self.viewbox is not None:
+            xext = (self.viewbox.maxlon - self.viewbox.minlon)/2
+            yext = (self.viewbox.maxlat - self.viewbox.minlat)/2
+            self.viewbox_x2 = Bbox(self.viewbox.minlon - xext, self.viewbox.minlat - yext,
+                                   self.viewbox.maxlon + xext, self.viewbox.maxlat + yext)
+
+
+    def restrict_min_max_rank(self, new_min: int, new_max: int) -> None:
+        """ Change the min_rank and max_rank fields to respect the
+            given boundaries.
+        """
+        assert new_min <= new_max
+        self.min_rank = max(self.min_rank, new_min)
+        self.max_rank = min(self.max_rank, new_max)
+
+
+    def is_impossible(self) -> bool:
+        """ Check if the parameter configuration is contradictionary and
+            cannot yield any results.
+        """
+        return (self.min_rank > self.max_rank
+                or (self.bounded_viewbox
+                    and self.viewbox is not None and self.near is not None
+                    and self.viewbox.contains(self.near))
+                or (self.layers is not None and not self.layers)
+                or (self.max_rank <= 4 and
+                    self.layers is not None and not self.layers & DataLayer.ADDRESS))
+
+
+    def layer_enabled(self, layer: DataLayer) -> bool:
+        """ Check if the given layer has been chosen. Also returns
+            true when layer restriction has been disabled completely.
+        """
+        return self.layers is None or bool(self.layers & layer)

nominatim/api/v1/__init__.py

@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Implementation of API version v1 (aka the legacy version).
+"""
+
+#pylint: disable=useless-import-alias
+
+from nominatim.api.v1.server_glue import (ASGIAdaptor as ASGIAdaptor,
+                                          EndpointFunc as EndpointFunc,
+                                          ROUTES as ROUTES)
+
+import nominatim.api.v1.format as _format
+
+list_formats = _format.dispatch.list_formats
+supports_format = _format.dispatch.supports_format
+format_result = _format.dispatch.format_result

nominatim/api/v1/classtypes.py

@@ -0,0 +1,200 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Hard-coded information about tag categories.
+
+These tables have been copied verbatim from the old PHP code. For future
+version a more flexible formatting is required.
+"""
+from typing import Tuple, Optional, Mapping, Union
+
+import nominatim.api as napi
+
+def get_label_tag(category: Tuple[str, str], extratags: Optional[Mapping[str, str]],
+                  rank: int, country: Optional[str]) -> str:
+    """ Create a label tag for the given place that can be used as an XML name.
+    """
+    if rank < 26 and extratags and 'place' in extratags:
+        label = extratags['place']
+    elif rank < 26 and extratags and 'linked_place' in extratags:
+        label = extratags['linked_place']
+    elif category == ('boundary', 'administrative'):
+        label = ADMIN_LABELS.get((country or '', int(rank/2)))\
+                or ADMIN_LABELS.get(('', int(rank/2)))\
+                or 'Administrative'
+    elif category[1] == 'postal_code':
+        label = 'postcode'
+    elif rank < 26:
+        label = category[1] if category[1] != 'yes' else category[0]
+    elif rank < 28:
+        label = 'road'
+    elif category[0] == 'place'\
+         and category[1] in ('house_number', 'house_name', 'country_code'):
+        label = category[1]
+    else:
+        label = category[0]
+
+    return label.lower().replace(' ', '_')
+
+
+def bbox_from_result(result: Union[napi.ReverseResult, napi.SearchResult]) -> napi.Bbox:
+    """ Compute a bounding box for the result. For ways and relations
+        a given boundingbox is used. For all other object, a box is computed
+        around the centroid according to dimensions derived from the
+        search rank.
+    """
+    if (result.osm_object and result.osm_object[0] == 'N') or result.bbox is None:
+        extent = NODE_EXTENT.get(result.category, 0.00005)
+        return napi.Bbox.from_point(result.centroid, extent)
+
+    return result.bbox
+
+
+# pylint: disable=line-too-long
+OSM_ATTRIBUTION = 'Data © OpenStreetMap contributors, ODbL 1.0. http://osm.org/copyright'
+
+
+OSM_TYPE_NAME = {
+    'N': 'node',
+    'W': 'way',
+    'R': 'relation'
+}
+
+
+ADMIN_LABELS = {
+  ('', 1): 'Continent',
+  ('', 2): 'Country',
+  ('', 3): 'Region',
+  ('', 4): 'State',
+  ('', 5): 'State District',
+  ('', 6): 'County',
+  ('', 7): 'Municipality',
+  ('', 8): 'City',
+  ('', 9): 'City District',
+  ('', 10): 'Suburb',
+  ('', 11): 'Neighbourhood',
+  ('', 12): 'City Block',
+  ('no', 3): 'State',
+  ('no', 4): 'County',
+  ('se', 3): 'State',
+  ('se', 4): 'County'
+}
+
+
+ICONS = {
+    ('boundary', 'administrative'): 'poi_boundary_administrative',
+    ('place', 'city'): 'poi_place_city',
+    ('place', 'town'): 'poi_place_town',
+    ('place', 'village'): 'poi_place_village',
+    ('place', 'hamlet'): 'poi_place_village',
+    ('place', 'suburb'): 'poi_place_village',
+    ('place', 'locality'): 'poi_place_village',
+    ('place', 'airport'): 'transport_airport2',
+    ('aeroway', 'aerodrome'): 'transport_airport2',
+    ('railway', 'station'): 'transport_train_station2',
+    ('amenity', 'place_of_worship'): 'place_of_worship_unknown3',
+    ('amenity', 'pub'): 'food_pub',
+    ('amenity', 'bar'): 'food_bar',
+    ('amenity', 'university'): 'education_university',
+    ('tourism', 'museum'): 'tourist_museum',
+    ('amenity', 'arts_centre'): 'tourist_art_gallery2',
+    ('tourism', 'zoo'): 'tourist_zoo',
+    ('tourism', 'theme_park'): 'poi_point_of_interest',
+    ('tourism', 'attraction'): 'poi_point_of_interest',
+    ('leisure', 'golf_course'): 'sport_golf',
+    ('historic', 'castle'): 'tourist_castle',
+    ('amenity', 'hospital'): 'health_hospital',
+    ('amenity', 'school'): 'education_school',
+    ('amenity', 'theatre'): 'tourist_theatre',
+    ('amenity', 'library'): 'amenity_library',
+    ('amenity', 'fire_station'): 'amenity_firestation3',
+    ('amenity', 'police'): 'amenity_police2',
+    ('amenity', 'bank'): 'money_bank2',
+    ('amenity', 'post_office'): 'amenity_post_office',
+    ('tourism', 'hotel'): 'accommodation_hotel2',
+    ('amenity', 'cinema'): 'tourist_cinema',
+    ('tourism', 'artwork'): 'tourist_art_gallery2',
+    ('historic', 'archaeological_site'): 'tourist_archaeological2',
+    ('amenity', 'doctors'): 'health_doctors',
+    ('leisure', 'sports_centre'): 'sport_leisure_centre',
+    ('leisure', 'swimming_pool'): 'sport_swimming_outdoor',
+    ('shop', 'supermarket'): 'shopping_supermarket',
+    ('shop', 'convenience'): 'shopping_convenience',
+    ('amenity', 'restaurant'): 'food_restaurant',
+    ('amenity', 'fast_food'): 'food_fastfood',
+    ('amenity', 'cafe'): 'food_cafe',
+    ('tourism', 'guest_house'): 'accommodation_bed_and_breakfast',
+    ('amenity', 'pharmacy'): 'health_pharmacy_dispensing',
+    ('amenity', 'fuel'): 'transport_fuel',
+    ('natural', 'peak'): 'poi_peak',
+    ('natural', 'wood'): 'landuse_coniferous_and_deciduous',
+    ('shop', 'bicycle'): 'shopping_bicycle',
+    ('shop', 'clothes'): 'shopping_clothes',
+    ('shop', 'hairdresser'): 'shopping_hairdresser',
+    ('shop', 'doityourself'): 'shopping_diy',
+    ('shop', 'estate_agent'): 'shopping_estateagent2',
+    ('shop', 'car'): 'shopping_car',
+    ('shop', 'garden_centre'): 'shopping_garden_centre',
+    ('shop', 'car_repair'): 'shopping_car_repair',
+    ('shop', 'bakery'): 'shopping_bakery',
+    ('shop', 'butcher'): 'shopping_butcher',
+    ('shop', 'apparel'): 'shopping_clothes',
+    ('shop', 'laundry'): 'shopping_laundrette',
+    ('shop', 'beverages'): 'shopping_alcohol',
+    ('shop', 'alcohol'): 'shopping_alcohol',
+    ('shop', 'optician'): 'health_opticians',
+    ('shop', 'chemist'): 'health_pharmacy',
+    ('shop', 'gallery'): 'tourist_art_gallery2',
+    ('shop', 'jewelry'): 'shopping_jewelry',
+    ('tourism', 'information'): 'amenity_information',
+    ('historic', 'ruins'): 'tourist_ruin',
+    ('amenity', 'college'): 'education_school',
+    ('historic', 'monument'): 'tourist_monument',
+    ('historic', 'memorial'): 'tourist_monument',
+    ('historic', 'mine'): 'poi_mine',
+    ('tourism', 'caravan_site'): 'accommodation_caravan_park',
+    ('amenity', 'bus_station'): 'transport_bus_station',
+    ('amenity', 'atm'): 'money_atm2',
+    ('tourism', 'viewpoint'): 'tourist_view_point',
+    ('tourism', 'guesthouse'): 'accommodation_bed_and_breakfast',
+    ('railway', 'tram'): 'transport_tram_stop',
+    ('amenity', 'courthouse'): 'amenity_court',
+    ('amenity', 'recycling'): 'amenity_recycling',
+    ('amenity', 'dentist'): 'health_dentist',
+    ('natural', 'beach'): 'tourist_beach',
+    ('railway', 'tram_stop'): 'transport_tram_stop',
+    ('amenity', 'prison'): 'amenity_prison',
+    ('highway', 'bus_stop'): 'transport_bus_stop2'
+}
+
+NODE_EXTENT = {
+    ('place', 'continent'): 25,
+    ('place', 'country'): 7,
+    ('place', 'state'): 2.6,
+    ('place', 'province'): 2.6,
+    ('place', 'region'): 1.0,
+    ('place', 'county'): 0.7,
+    ('place', 'city'): 0.16,
+    ('place', 'municipality'): 0.16,
+    ('place', 'island'): 0.32,
+    ('place', 'postcode'): 0.16,
+    ('place', 'town'): 0.04,
+    ('place', 'village'): 0.02,
+    ('place', 'hamlet'): 0.02,
+    ('place', 'district'): 0.02,
+    ('place', 'borough'): 0.02,
+    ('place', 'suburb'): 0.02,
+    ('place', 'locality'): 0.01,
+    ('place', 'neighbourhood'): 0.01,
+    ('place', 'quarter'): 0.01,
+    ('place', 'city_block'): 0.01,
+    ('landuse', 'farm'): 0.01,
+    ('place', 'farm'): 0.01,
+    ('place', 'airport'): 0.015,
+    ('aeroway', 'aerodrome'): 0.015,
+    ('railway', 'station'): 0.005
+}

nominatim/api/v1/format.py

@@ -0,0 +1,256 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Output formatters for API version v1.
+"""
+from typing import List, Dict, Mapping, Any
+import collections
+import datetime as dt
+
+import nominatim.api as napi
+from nominatim.api.result_formatting import FormatDispatcher
+from nominatim.api.v1.classtypes import ICONS
+from nominatim.api.v1 import format_json, format_xml
+from nominatim.utils.json_writer import JsonWriter
+
+class RawDataList(List[Dict[str, Any]]):
+    """ Data type for formatting raw data lists 'as is' in json.
+    """
+
+dispatch = FormatDispatcher()
+
+@dispatch.format_func(napi.StatusResult, 'text')
+def _format_status_text(result: napi.StatusResult, _: Mapping[str, Any]) -> str:
+    if result.status:
+        return f"ERROR: {result.message}"
+
+    return 'OK'
+
+
+@dispatch.format_func(napi.StatusResult, 'json')
+def _format_status_json(result: napi.StatusResult, _: Mapping[str, Any]) -> str:
+    out = JsonWriter()
+
+    out.start_object()\
+         .keyval('status', result.status)\
+         .keyval('message', result.message)\
+         .keyval_not_none('data_updated', result.data_updated,
+                          lambda v: v.isoformat())\
+         .keyval('software_version', str(result.software_version))\
+         .keyval_not_none('database_version', result.database_version, str)\
+       .end_object()
+
+    return out()
+
+
+def _add_address_row(writer: JsonWriter, row: napi.AddressLine,
+                     locales: napi.Locales) -> None:
+    writer.start_object()\
+            .keyval('localname', locales.display_name(row.names))\
+            .keyval_not_none('place_id', row.place_id)
+
+    if row.osm_object is not None:
+        writer.keyval('osm_id', row.osm_object[1])\
+              .keyval('osm_type', row.osm_object[0])
+
+    if row.extratags:
+        writer.keyval_not_none('place_type', row.extratags.get('place_type'))
+
+    writer.keyval('class', row.category[0])\
+          .keyval('type', row.category[1])\
+          .keyval_not_none('admin_level', row.admin_level)\
+          .keyval('rank_address', row.rank_address)\
+          .keyval('distance', row.distance)\
+          .keyval('isaddress', row.isaddress)\
+        .end_object()
+
+
+def _add_address_rows(writer: JsonWriter, section: str, rows: napi.AddressLines,
+                      locales: napi.Locales) -> None:
+    writer.key(section).start_array()
+    for row in rows:
+        _add_address_row(writer, row, locales)
+        writer.next()
+    writer.end_array().next()
+
+
+def _add_parent_rows_grouped(writer: JsonWriter, rows: napi.AddressLines,
+                             locales: napi.Locales) -> None:
+    # group by category type
+    data = collections.defaultdict(list)
+    for row in rows:
+        sub = JsonWriter()
+        _add_address_row(sub, row, locales)
+        data[row.category[1]].append(sub())
+
+    writer.key('hierarchy').start_object()
+    for group, grouped in data.items():
+        writer.key(group).start_array()
+        grouped.sort() # sorts alphabetically by local name
+        for line in grouped:
+            writer.raw(line).next()
+        writer.end_array().next()
+
+    writer.end_object().next()
+
+
+@dispatch.format_func(napi.DetailedResult, 'json')
+def _format_details_json(result: napi.DetailedResult, options: Mapping[str, Any]) -> str:
+    locales = options.get('locales', napi.Locales())
+    geom = result.geometry.get('geojson')
+    centroid = result.centroid.to_geojson()
+
+    out = JsonWriter()
+    out.start_object()\
+         .keyval_not_none('place_id', result.place_id)\
+         .keyval_not_none('parent_place_id', result.parent_place_id)
+
+    if result.osm_object is not None:
+        out.keyval('osm_type', result.osm_object[0])\
+           .keyval('osm_id', result.osm_object[1])
+
+    out.keyval('category', result.category[0])\
+         .keyval('type', result.category[1])\
+         .keyval('admin_level', result.admin_level)\
+         .keyval('localname', result.locale_name or '')\
+         .keyval('names', result.names or {})\
+         .keyval('addresstags', result.address or {})\
+         .keyval_not_none('housenumber', result.housenumber)\
+         .keyval_not_none('calculated_postcode', result.postcode)\
+         .keyval_not_none('country_code', result.country_code)\
+         .keyval_not_none('indexed_date', result.indexed_date, lambda v: v.isoformat())\
+         .keyval_not_none('importance', result.importance)\
+         .keyval('calculated_importance', result.calculated_importance())\
+         .keyval('extratags', result.extratags or {})\
+         .keyval_not_none('calculated_wikipedia', result.wikipedia)\
+         .keyval('rank_address', result.rank_address)\
+         .keyval('rank_search', result.rank_search)\
+         .keyval('isarea', 'Polygon' in (geom or result.geometry.get('type') or ''))\
+         .key('centroid').raw(centroid).next()\
+         .key('geometry').raw(geom or centroid).next()
+
+    if options.get('icon_base_url', None):
+        icon = ICONS.get(result.category)
+        if icon:
+            out.keyval('icon', f"{options['icon_base_url']}/{icon}.p.20.png")
+
+    if result.address_rows is not None:
+        _add_address_rows(out, 'address', result.address_rows, locales)
+
+    if result.linked_rows:
+        _add_address_rows(out, 'linked_places', result.linked_rows, locales)
+
+    if result.name_keywords is not None or result.address_keywords is not None:
+        out.key('keywords').start_object()
+
+        for sec, klist in (('name', result.name_keywords), ('address', result.address_keywords)):
+            out.key(sec).start_array()
+            for word in (klist or []):
+                out.start_object()\
+                     .keyval('id', word.word_id)\
+                     .keyval('token', word.word_token)\
+                   .end_object().next()
+            out.end_array().next()
+
+        out.end_object().next()
+
+    if result.parented_rows is not None:
+        if options.get('group_hierarchy', False):
+            _add_parent_rows_grouped(out, result.parented_rows, locales)
+        else:
+            _add_address_rows(out, 'hierarchy', result.parented_rows, locales)
+
+    out.end_object()
+
+    return out()
+
+
+@dispatch.format_func(napi.ReverseResults, 'xml')
+def _format_reverse_xml(results: napi.ReverseResults, options: Mapping[str, Any]) -> str:
+    return format_xml.format_base_xml(results,
+                                      options, True, 'reversegeocode',
+                                      {'querystring': options.get('query', '')})
+
+
+@dispatch.format_func(napi.ReverseResults, 'geojson')
+def _format_reverse_geojson(results: napi.ReverseResults,
+                            options: Mapping[str, Any]) -> str:
+    return format_json.format_base_geojson(results, options, True)
+
+
+@dispatch.format_func(napi.ReverseResults, 'geocodejson')
+def _format_reverse_geocodejson(results: napi.ReverseResults,
+                                options: Mapping[str, Any]) -> str:
+    return format_json.format_base_geocodejson(results, options, True)
+
+
+@dispatch.format_func(napi.ReverseResults, 'json')
+def _format_reverse_json(results: napi.ReverseResults,
+                         options: Mapping[str, Any]) -> str:
+    return format_json.format_base_json(results, options, True,
+                                        class_label='class')
+
+
+@dispatch.format_func(napi.ReverseResults, 'jsonv2')
+def _format_reverse_jsonv2(results: napi.ReverseResults,
+                           options: Mapping[str, Any]) -> str:
+    return format_json.format_base_json(results, options, True,
+                                        class_label='category')
+
+
+@dispatch.format_func(napi.SearchResults, 'xml')
+def _format_search_xml(results: napi.SearchResults, options: Mapping[str, Any]) -> str:
+    extra = {'querystring': options.get('query', '')}
+    for attr in ('more_url', 'exclude_place_ids', 'viewbox'):
+        if options.get(attr):
+            extra[attr] = options[attr]
+    return format_xml.format_base_xml(results, options, False, 'searchresults',
+                                      extra)
+
+
+
+@dispatch.format_func(napi.SearchResults, 'geojson')
+def _format_search_geojson(results: napi.SearchResults,
+                            options: Mapping[str, Any]) -> str:
+    return format_json.format_base_geojson(results, options, False)
+
+
+@dispatch.format_func(napi.SearchResults, 'geocodejson')
+def _format_search_geocodejson(results: napi.SearchResults,
+                                options: Mapping[str, Any]) -> str:
+    return format_json.format_base_geocodejson(results, options, False)
+
+
+@dispatch.format_func(napi.SearchResults, 'json')
+def _format_search_json(results: napi.SearchResults,
+                         options: Mapping[str, Any]) -> str:
+    return format_json.format_base_json(results, options, False,
+                                        class_label='class')
+
+
+@dispatch.format_func(napi.SearchResults, 'jsonv2')
+def _format_search_jsonv2(results: napi.SearchResults,
+                           options: Mapping[str, Any]) -> str:
+    return format_json.format_base_json(results, options, False,
+                                        class_label='category')
+
+@dispatch.format_func(RawDataList, 'json')
+def _format_raw_data_json(results: RawDataList,  _: Mapping[str, Any]) -> str:
+    out = JsonWriter()
+    out.start_array()
+    for res in results:
+        out.start_object()
+        for k, v in res.items():
+            if isinstance(v, dt.datetime):
+                out.keyval(k, v.isoformat(sep= ' ', timespec='seconds'))
+            else:
+                out.keyval(k, v)
+        out.end_object().next()
+
+    out.end_array()
+
+    return out()

nominatim/api/v1/format_json.py

@@ -0,0 +1,275 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Helper functions for output of results in json formats.
+"""
+from typing import Mapping, Any, Optional, Tuple, Union
+
+import nominatim.api as napi
+import nominatim.api.v1.classtypes as cl
+from nominatim.utils.json_writer import JsonWriter
+
+#pylint: disable=too-many-branches
+
+def _write_osm_id(out: JsonWriter, osm_object: Optional[Tuple[str, int]]) -> None:
+    if osm_object is not None:
+        out.keyval_not_none('osm_type', cl.OSM_TYPE_NAME.get(osm_object[0], None))\
+           .keyval('osm_id', osm_object[1])
+
+
+def _write_typed_address(out: JsonWriter, address: Optional[napi.AddressLines],
+                               country_code: Optional[str]) -> None:
+    parts = {}
+    for line in (address or []):
+        if line.isaddress:
+            if line.local_name:
+                label = cl.get_label_tag(line.category, line.extratags,
+                                         line.rank_address, country_code)
+                if label not in parts:
+                    parts[label] = line.local_name
+            if line.names and 'ISO3166-2' in line.names and line.admin_level:
+                parts[f"ISO3166-2-lvl{line.admin_level}"] = line.names['ISO3166-2']
+
+    for k, v in parts.items():
+        out.keyval(k, v)
+
+    if country_code:
+        out.keyval('country_code', country_code)
+
+
+def _write_geocodejson_address(out: JsonWriter,
+                               address: Optional[napi.AddressLines],
+                               obj_place_id: Optional[int],
+                               country_code: Optional[str]) -> None:
+    extra = {}
+    for line in (address or []):
+        if line.isaddress and line.local_name:
+            if line.category[1] in ('postcode', 'postal_code'):
+                out.keyval('postcode', line.local_name)
+            elif line.category[1] == 'house_number':
+                out.keyval('housenumber', line.local_name)
+            elif (obj_place_id is None or obj_place_id != line.place_id) \
+                 and line.rank_address >= 4 and line.rank_address < 28:
+                rank_name = GEOCODEJSON_RANKS[line.rank_address]
+                if rank_name not in extra:
+                    extra[rank_name] = line.local_name
+
+
+    for k, v in extra.items():
+        out.keyval(k, v)
+
+    if country_code:
+        out.keyval('country_code', country_code)
+
+
+def format_base_json(results: Union[napi.ReverseResults, napi.SearchResults],
+                     options: Mapping[str, Any], simple: bool,
+                     class_label: str) -> str:
+    """ Return the result list as a simple json string in custom Nominatim format.
+    """
+    out = JsonWriter()
+
+    if simple:
+        if not results:
+            return '{"error":"Unable to geocode"}'
+    else:
+        out.start_array()
+
+    for result in results:
+        out.start_object()\
+             .keyval_not_none('place_id', result.place_id)\
+             .keyval('licence', cl.OSM_ATTRIBUTION)\
+
+        _write_osm_id(out, result.osm_object)
+
+        out.keyval('lat', f"{result.centroid.lat}")\
+             .keyval('lon', f"{result.centroid.lon}")\
+             .keyval(class_label, result.category[0])\
+             .keyval('type', result.category[1])\
+             .keyval('place_rank', result.rank_search)\
+             .keyval('importance', result.calculated_importance())\
+             .keyval('addresstype', cl.get_label_tag(result.category, result.extratags,
+                                                     result.rank_address,
+                                                     result.country_code))\
+             .keyval('name', result.locale_name or '')\
+             .keyval('display_name', result.display_name or '')
+
+
+        if options.get('icon_base_url', None):
+            icon = cl.ICONS.get(result.category)
+            if icon:
+                out.keyval('icon', f"{options['icon_base_url']}/{icon}.p.20.png")
+
+        if options.get('addressdetails', False):
+            out.key('address').start_object()
+            _write_typed_address(out, result.address_rows, result.country_code)
+            out.end_object().next()
+
+        if options.get('extratags', False):
+            out.keyval('extratags', result.extratags)
+
+        if options.get('namedetails', False):
+            out.keyval('namedetails', result.names)
+
+        bbox = cl.bbox_from_result(result)
+        out.key('boundingbox').start_array()\
+             .value(f"{bbox.minlat:0.7f}").next()\
+             .value(f"{bbox.maxlat:0.7f}").next()\
+             .value(f"{bbox.minlon:0.7f}").next()\
+             .value(f"{bbox.maxlon:0.7f}").next()\
+           .end_array().next()
+
+        if result.geometry:
+            for key in ('text', 'kml'):
+                out.keyval_not_none('geo' + key, result.geometry.get(key))
+            if 'geojson' in result.geometry:
+                out.key('geojson').raw(result.geometry['geojson']).next()
+            out.keyval_not_none('svg', result.geometry.get('svg'))
+
+        out.end_object()
+
+        if simple:
+            return out()
+
+        out.next()
+
+    out.end_array()
+
+    return out()
+
+
+def format_base_geojson(results: Union[napi.ReverseResults, napi.SearchResults],
+                        options: Mapping[str, Any],
+                        simple: bool) -> str:
+    """ Return the result list as a geojson string.
+    """
+    if not results and simple:
+        return '{"error":"Unable to geocode"}'
+
+    out = JsonWriter()
+
+    out.start_object()\
+         .keyval('type', 'FeatureCollection')\
+         .keyval('licence', cl.OSM_ATTRIBUTION)\
+         .key('features').start_array()
+
+    for result in results:
+        out.start_object()\
+             .keyval('type', 'Feature')\
+             .key('properties').start_object()
+
+        out.keyval_not_none('place_id', result.place_id)
+
+        _write_osm_id(out, result.osm_object)
+
+        out.keyval('place_rank', result.rank_search)\
+           .keyval('category', result.category[0])\
+           .keyval('type', result.category[1])\
+           .keyval('importance', result.calculated_importance())\
+           .keyval('addresstype', cl.get_label_tag(result.category, result.extratags,
+                                                   result.rank_address,
+                                                   result.country_code))\
+           .keyval('name', result.locale_name or '')\
+           .keyval('display_name', result.display_name or '')
+
+        if options.get('addressdetails', False):
+            out.key('address').start_object()
+            _write_typed_address(out, result.address_rows, result.country_code)
+            out.end_object().next()
+
+        if options.get('extratags', False):
+            out.keyval('extratags', result.extratags)
+
+        if options.get('namedetails', False):
+            out.keyval('namedetails', result.names)
+
+        out.end_object().next() # properties
+
+        out.key('bbox').start_array()
+        for coord in cl.bbox_from_result(result).coords:
+            out.float(coord, 7).next()
+        out.end_array().next()
+
+        out.key('geometry').raw(result.geometry.get('geojson')
+                                or result.centroid.to_geojson()).next()
+
+        out.end_object().next()
+
+    out.end_array().next().end_object()
+
+    return out()
+
+
+def format_base_geocodejson(results: Union[napi.ReverseResults, napi.SearchResults],
+                            options: Mapping[str, Any], simple: bool) -> str:
+    """ Return the result list as a geocodejson string.
+    """
+    if not results and simple:
+        return '{"error":"Unable to geocode"}'
+
+    out = JsonWriter()
+
+    out.start_object()\
+         .keyval('type', 'FeatureCollection')\
+         .key('geocoding').start_object()\
+           .keyval('version', '0.1.0')\
+           .keyval('attribution', cl.OSM_ATTRIBUTION)\
+           .keyval('licence', 'ODbL')\
+           .keyval_not_none('query', options.get('query'))\
+           .end_object().next()\
+         .key('features').start_array()
+
+    for result in results:
+        out.start_object()\
+             .keyval('type', 'Feature')\
+             .key('properties').start_object()\
+               .key('geocoding').start_object()
+
+        out.keyval_not_none('place_id', result.place_id)
+
+        _write_osm_id(out, result.osm_object)
+
+        out.keyval('osm_key', result.category[0])\
+           .keyval('osm_value', result.category[1])\
+           .keyval('type', GEOCODEJSON_RANKS[max(3, min(28, result.rank_address))])\
+           .keyval_not_none('accuracy', getattr(result, 'distance', None), transform=int)\
+           .keyval('label', result.display_name or '')\
+           .keyval_not_none('name', result.locale_name or None)\
+
+        if options.get('addressdetails', False):
+            _write_geocodejson_address(out, result.address_rows, result.place_id,
+                                       result.country_code)
+
+            out.key('admin').start_object()
+            if result.address_rows:
+                for line in result.address_rows:
+                    if line.isaddress and (line.admin_level or 15) < 15 and line.local_name \
+                       and line.category[0] == 'boundary' and line.category[1] == 'administrative':
+                        out.keyval(f"level{line.admin_level}", line.local_name)
+            out.end_object().next()
+
+        out.end_object().next().end_object().next()
+
+        out.key('geometry').raw(result.geometry.get('geojson')
+                                or result.centroid.to_geojson()).next()
+
+        out.end_object().next()
+
+    out.end_array().next().end_object()
+
+    return out()
+
+
+GEOCODEJSON_RANKS = {
+    3: 'locality',
+    4: 'country',
+    5: 'state', 6: 'state', 7: 'state', 8: 'state', 9: 'state',
+    10: 'county', 11: 'county', 12: 'county',
+    13: 'city', 14: 'city', 15: 'city', 16: 'city',
+    17: 'district', 18: 'district', 19: 'district', 20: 'district', 21: 'district',
+    22: 'locality', 23: 'locality', 24: 'locality',
+    25: 'street', 26: 'street', 27: 'street', 28: 'house'}

nominatim/api/v1/format_xml.py

@@ -0,0 +1,125 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Helper functions for output of results in XML format.
+"""
+from typing import Mapping, Any, Optional, Union
+import datetime as dt
+import xml.etree.ElementTree as ET
+
+import nominatim.api as napi
+import nominatim.api.v1.classtypes as cl
+
+#pylint: disable=too-many-branches
+
+def _write_xml_address(root: ET.Element, address: napi.AddressLines,
+                       country_code: Optional[str]) -> None:
+    parts = {}
+    for line in address:
+        if line.isaddress:
+            if line.local_name:
+                label = cl.get_label_tag(line.category, line.extratags,
+                                         line.rank_address, country_code)
+                if label not in parts:
+                    parts[label] = line.local_name
+            if line.names and 'ISO3166-2' in line.names and line.admin_level:
+                parts[f"ISO3166-2-lvl{line.admin_level}"] = line.names['ISO3166-2']
+
+    for k,v in parts.items():
+        ET.SubElement(root, k).text = v
+
+    if country_code:
+        ET.SubElement(root, 'country_code').text = country_code
+
+
+def _create_base_entry(result: Union[napi.ReverseResult, napi.SearchResult],
+                       root: ET.Element, simple: bool) -> ET.Element:
+    place = ET.SubElement(root, 'result' if simple else 'place')
+    if result.place_id is not None:
+        place.set('place_id', str(result.place_id))
+    if result.osm_object:
+        osm_type = cl.OSM_TYPE_NAME.get(result.osm_object[0], None)
+        if osm_type is not None:
+            place.set('osm_type', osm_type)
+        place.set('osm_id', str(result.osm_object[1]))
+    if result.names and 'ref' in result.names:
+        place.set('ref', result.names['ref'])
+    elif result.locale_name:
+        # bug reproduced from PHP
+        place.set('ref', result.locale_name)
+    place.set('lat', f"{result.centroid.lat:.7f}")
+    place.set('lon', f"{result.centroid.lon:.7f}")
+
+    bbox = cl.bbox_from_result(result)
+    place.set('boundingbox',
+              f"{bbox.minlat:.7f},{bbox.maxlat:.7f},{bbox.minlon:.7f},{bbox.maxlon:.7f}")
+
+    place.set('place_rank', str(result.rank_search))
+    place.set('address_rank', str(result.rank_address))
+
+    if result.geometry:
+        for key in ('text', 'svg'):
+            if key in result.geometry:
+                place.set('geo' + key, result.geometry[key])
+        if 'kml' in result.geometry:
+            ET.SubElement(root if simple else place, 'geokml')\
+              .append(ET.fromstring(result.geometry['kml']))
+        if 'geojson' in result.geometry:
+            place.set('geojson', result.geometry['geojson'])
+
+    if simple:
+        place.text = result.display_name or ''
+    else:
+        place.set('display_name', result.display_name or '')
+        place.set('class', result.category[0])
+        place.set('type', result.category[1])
+        place.set('importance', str(result.calculated_importance()))
+
+    return place
+
+
+def format_base_xml(results: Union[napi.ReverseResults, napi.SearchResults],
+                    options: Mapping[str, Any],
+                    simple: bool, xml_root_tag: str,
+                    xml_extra_info: Mapping[str, str]) -> str:
+    """ Format the result into an XML response. With 'simple' exactly one
+        result will be output, otherwise a list.
+    """
+    root = ET.Element(xml_root_tag)
+    root.set('timestamp', dt.datetime.utcnow().strftime('%a, %d %b %Y %H:%M:%S +00:00'))
+    root.set('attribution', cl.OSM_ATTRIBUTION)
+    for k, v in xml_extra_info.items():
+        root.set(k, v)
+
+    if simple and not results:
+        ET.SubElement(root, 'error').text = 'Unable to geocode'
+
+    for result in results:
+        place = _create_base_entry(result, root, simple)
+
+        if not simple and options.get('icon_base_url', None):
+            icon = cl.ICONS.get(result.category)
+            if icon:
+                place.set('icon', icon)
+
+        if options.get('addressdetails', False) and result.address_rows:
+            _write_xml_address(ET.SubElement(root, 'addressparts') if simple else place,
+                               result.address_rows, result.country_code)
+
+        if options.get('extratags', False):
+            eroot = ET.SubElement(root if simple else place, 'extratags')
+            if result.extratags:
+                for k, v in result.extratags.items():
+                    ET.SubElement(eroot, 'tag', attrib={'key': k, 'value': v})
+
+        if options.get('namedetails', False):
+            eroot = ET.SubElement(root if simple else place, 'namedetails')
+            if result.names:
+                for k,v in result.names.items():
+                    ET.SubElement(eroot, 'name', attrib={'desc': k}).text = v
+
+    return '<?xml version="1.0" encoding="UTF-8" ?>\n' + ET.tostring(root, encoding='unicode')

nominatim/api/v1/helpers.py

@@ -0,0 +1,201 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2023 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Helper function for parsing parameters and and outputting data
+specifically for the v1 version of the API.
+"""
+from typing import Tuple, Optional, Any, Dict, Iterable
+from itertools import chain
+import re
+
+from nominatim.api.results import SearchResult, SearchResults, SourceTable
+from nominatim.api.types import SearchDetails, GeometryFormat
+
+REVERSE_MAX_RANKS = [2, 2, 2,   # 0-2   Continent/Sea
+                     4, 4,      # 3-4   Country
+                     8,         # 5     State
+                     10, 10,    # 6-7   Region
+                     12, 12,    # 8-9   County
+                     16, 17,    # 10-11 City
+                     18,        # 12    Town
+                     19,        # 13    Village/Suburb
+                     22,        # 14    Hamlet/Neighbourhood
+                     25,        # 15    Localities
+                     26,        # 16    Major Streets
+                     27,        # 17    Minor Streets
+                     30         # 18    Building
+                    ]
+
+
+def zoom_to_rank(zoom: int) -> int:
+    """ Convert a zoom parameter into a rank according to the v1 API spec.
+    """
+    return REVERSE_MAX_RANKS[max(0, min(18, zoom))]
+
+
+FEATURE_TYPE_TO_RANK: Dict[Optional[str], Tuple[int, int]] = {
+    'country': (4, 4),
+    'state': (8, 8),
+    'city': (14, 16),
+    'settlement': (8, 20)
+}
+
+
+def feature_type_to_rank(feature_type: Optional[str]) -> Tuple[int, int]:
+    """ Convert a feature type parameter to a tuple of
+        feature type name, minimum rank and maximum rank.
+    """
+    return FEATURE_TYPE_TO_RANK.get(feature_type, (0, 30))
+
+
+#pylint: disable=too-many-arguments,too-many-branches
+def extend_query_parts(queryparts: Dict[str, Any], details: Dict[str, Any],
+                       feature_type: Optional[str],
+                       namedetails: bool, extratags: bool,
+                       excluded: Iterable[str]) -> None:
+    """ Add parameters from details dictionary to the query parts
+        dictionary which is suitable as URL parameter dictionary.
+    """
+    parsed = SearchDetails.from_kwargs(details)
+    if parsed.geometry_output != GeometryFormat.NONE:
+        if GeometryFormat.GEOJSON in parsed.geometry_output:
+            queryparts['polygon_geojson'] = '1'
+        if GeometryFormat.KML in parsed.geometry_output:
+            queryparts['polygon_kml'] = '1'
+        if GeometryFormat.SVG in parsed.geometry_output:
+            queryparts['polygon_svg'] = '1'
+        if GeometryFormat.TEXT in parsed.geometry_output:
+            queryparts['polygon_text'] = '1'
+    if parsed.address_details:
+        queryparts['addressdetails'] = '1'
+    if namedetails:
+        queryparts['namedetails'] = '1'
+    if extratags:
+        queryparts['extratags'] = '1'
+    if parsed.geometry_simplification > 0.0:
+        queryparts['polygon_threshold'] = f"{parsed.geometry_simplification:.6g}"
+    if parsed.max_results != 10:
+        queryparts['limit'] = str(parsed.max_results)
+    if parsed.countries:
+        queryparts['countrycodes'] = ','.join(parsed.countries)
+    queryparts['exclude_place_ids'] = \
+        ','.join(chain(excluded, map(str, (e for e in parsed.excluded if e > 0))))
+    if parsed.viewbox:
+        queryparts['viewbox'] = ','.join(f"{c:.7g}" for c in parsed.viewbox.coords)
+    if parsed.bounded_viewbox:
+        queryparts['bounded'] = '1'
+    if not details['dedupe']:
+        queryparts['dedupe'] = '0'
+    if feature_type in FEATURE_TYPE_TO_RANK:
+        queryparts['featureType'] = feature_type
+
+
+def deduplicate_results(results: SearchResults, max_results: int) -> SearchResults:
+    """ Remove results that look like duplicates.
+
+        Two results are considered the same if they have the same OSM ID
+        or if they have the same category, display name and rank.
+    """
+    osm_ids_done = set()
+    classification_done = set()
+    deduped = SearchResults()
+    for result in results:
+        if result.source_table == SourceTable.POSTCODE:
+            assert result.names and 'ref' in result.names
+            if any(_is_postcode_relation_for(r, result.names['ref']) for r in results):
+                continue
+        if result.source_table == SourceTable.PLACEX:
+            classification = (result.osm_object[0] if result.osm_object else None,
+                              result.category,
+                              result.display_name,
+                              result.rank_address)
+            if result.osm_object not in osm_ids_done \
+               and classification not in classification_done:
+                deduped.append(result)
+            osm_ids_done.add(result.osm_object)
+            classification_done.add(classification)
+        else:
+            deduped.append(result)
+        if len(deduped) >= max_results:
+            break
+
+    return deduped
+
+
+def _is_postcode_relation_for(result: SearchResult, postcode: str) -> bool:
+    return result.source_table == SourceTable.PLACEX \
+           and result.osm_object is not None \
+           and result.osm_object[0] == 'R' \
+           and result.category == ('boundary', 'postal_code') \
+           and result.names is not None \
+           and result.names.get('ref') == postcode
+
+
+def _deg(axis:str) -> str:
+    return f"(?P<{axis}_deg>\\d+\\.\\d+)°?"
+
+def _deg_min(axis: str) -> str:
+    return f"(?P<{axis}_deg>\\d+)[°\\s]+(?P<{axis}_min>[\\d.]+)[′']*"
+
+def _deg_min_sec(axis: str) -> str:
+    return f"(?P<{axis}_deg>\\d+)[°\\s]+(?P<{axis}_min>\\d+)[′'\\s]+(?P<{axis}_sec>[\\d.]+)[\"″]*"
+
+COORD_REGEX = [re.compile(r'(?:(?P<pre>.*?)\s+)??' + r + r'(?:\s+(?P<post>.*))?') for r in (
+    r"(?P<ns>[NS])\s*" + _deg('lat') + r"[\s,]+" + r"(?P<ew>[EW])\s*" + _deg('lon'),
+    _deg('lat') + r"\s*(?P<ns>[NS])[\s,]+" + _deg('lon') + r"\s*(?P<ew>[EW])",
+    r"(?P<ns>[NS])\s*" + _deg_min('lat') + r"[\s,]+" + r"(?P<ew>[EW])\s*" + _deg_min('lon'),
+    _deg_min('lat') + r"\s*(?P<ns>[NS])[\s,]+" + _deg_min('lon') + r"\s*(?P<ew>[EW])",
+    r"(?P<ns>[NS])\s*" + _deg_min_sec('lat') + r"[\s,]+" + r"(?P<ew>[EW])\s*" + _deg_min_sec('lon'),
+    _deg_min_sec('lat') + r"\s*(?P<ns>[NS])[\s,]+" + _deg_min_sec('lon') + r"\s*(?P<ew>[EW])",
+    r"\[?(?P<lat_deg>[+-]?\d+\.\d+)[\s,]+(?P<lon_deg>[+-]?\d+\.\d+)\]?"
+)]
+
+def extract_coords_from_query(query: str) -> Tuple[str, Optional[float], Optional[float]]:
+    """ Look for something that is formatted like a coordinate at the
+        beginning or end of the query. If found, extract the coordinate and
+        return the remaining query (or the empty string if the query
+        consisted of nothing but a coordinate).
+
+        Only the first match will be returned.
+    """
+    for regex in COORD_REGEX:
+        match = regex.fullmatch(query)
+        if match is None:
+            continue
+        groups = match.groupdict()
+        if not groups['pre'] or not groups['post']:
+            x = float(groups['lon_deg']) \
+                + float(groups.get('lon_min', 0.0)) / 60.0 \
+                + float(groups.get('lon_sec', 0.0)) / 3600.0
+            if groups.get('ew') == 'W':
+                x = -x
+            y = float(groups['lat_deg']) \
+                + float(groups.get('lat_min', 0.0)) / 60.0 \
+                + float(groups.get('lat_sec', 0.0)) / 3600.0
+            if groups.get('ns') == 'S':
+                y = -y
+            return groups['pre'] or groups['post'] or '', x, y
+
+    return query, None, None
+
+
+CATEGORY_REGEX = re.compile(r'(?P<pre>.*?)\[(?P<cls>[a-zA-Z_]+)=(?P<typ>[a-zA-Z_]+)\](?P<post>.*)')
+
+def extract_category_from_query(query: str) -> Tuple[str, Optional[str], Optional[str]]:
+    """ Extract a hidden category specification of the form '[key=value]' from
+        the query. If found, extract key and value  and
+        return the remaining query (or the empty string if the query
+        consisted of nothing but a category).
+
+        Only the first match will be returned.
+    """
+    match = CATEGORY_REGEX.search(query)
+    if match is not None:
+        return (match.group('pre').strip() + ' ' + match.group('post').strip()).strip(), \
+               match.group('cls'), match.group('typ')
+
+    return query, None, None