Add script to generate taginfo project description

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

@@ -25,7 +25,7 @@ runs:
           shell: bash
         - 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${LUA_VERSION}
+            sudo apt-get install -y -qq libboost-system-dev libboost-filesystem-dev libexpat1-dev zlib1g-dev libbz2-dev libpq-dev libproj-dev libicu-dev liblua${LUA_VERSION}-dev lua${LUA_VERSION} lua-dkjson
             if [ "$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 GeoAlchemy2==0.10.0 datrie asyncpg
             else

settings/flex-base.lua

@@ -11,6 +11,11 @@ local ADDRESS_TAGS = nil
 local SAVE_EXTRA_MAINS = false
 local POSTCODE_FALLBACK = true
 
+-- tables required for taginfo
+module.TAGINFO_MAIN = {keys = {}, delete_tags = {}}
+module.TAGINFO_NAME_KEYS = {}
+module.TAGINFO_ADDRESS_KEYS = {}
+
 
 -- The single place table.
 local place_table = osm2pgsql.define_table{
@@ -372,6 +377,17 @@ function module.tag_group(data)
     end
 end
 
+-- Returns prefix part of the keys, and reject suffix matching keys
+local function process_key(key)
+    if key:sub(1, 1) == '*' then
+        return nil
+    end
+    if key:sub(#key, #key) == '*' then
+        return key:sub(1, #key - 2)
+    end
+    return key
+end
+
 -- Process functions for all data types
 function module.process_node(object)
 
@@ -465,14 +481,29 @@ function module.set_prefilters(data)
     PRE_DELETE = module.tag_match{keys = data.delete_keys, tags = data.delete_tags}
     PRE_EXTRAS = module.tag_match{keys = data.extra_keys,
                                   tags = data.extra_tags}
+    module.TAGINFO_MAIN.delete_tags = data.delete_tags
 end
 
 function module.set_main_tags(data)
     MAIN_KEYS = data
+    local keys = {}
+    for k, _ in pairs(data) do
+        table.insert(keys, k)
+    end
+    module.TAGINFO_MAIN.keys = keys
 end
 
 function module.set_name_tags(data)
     NAMES = module.tag_group(data)
+
+    for _, lst in pairs(data) do
+        for _, k in ipairs(lst) do
+            local key = process_key(k)
+            if key ~= nil then
+                module.TAGINFO_NAME_KEYS[key] = true
+            end
+        end
+    end
 end
 
 function module.set_address_tags(data)
@@ -480,8 +511,18 @@ function module.set_address_tags(data)
         POSTCODE_FALLBACK = data.postcode_fallback
         data.postcode_fallback = nil
     end
-
     ADDRESS_TAGS = module.tag_group(data)
+
+    for _, lst in pairs(data) do
+        if lst ~= nil then
+            for _, k in ipairs(lst) do
+                local key = process_key(k)
+                if key ~= nil then
+                    module.TAGINFO_ADDRESS_KEYS[key] = true
+                end
+            end
+        end
+    end
 end
 
 function module.set_unused_handling(data)

settings/import-extratags.lua

@@ -7,7 +7,6 @@ flex.set_main_tags{
     historic = 'always',
     military = 'always',
     natural = 'named',
-    landuse = 'named',
     highway = {'always',
                street_lamp = 'named',
                traffic_signals = 'named',

settings/import-full.lua

@@ -7,7 +7,6 @@ flex.set_main_tags{
     historic = 'always',
     military = 'always',
     natural = 'named',
-    landuse = 'named',
     highway = {'always',
                street_lamp = 'named',
                traffic_signals = 'named',

settings/taginfo.lua

@@ -0,0 +1,74 @@
+-- Prints taginfo project description in the standard output
+--
+
+-- create fake "osm2pgsql" table for flex-base, originally created by the main C++ program
+osm2pgsql = {}
+function osm2pgsql.define_table(...) end
+
+-- provide path to flex-style lua file
+flex = require('import-extratags')
+local json = require ('dkjson')
+
+
+------------ helper functions ---------------------
+
+function get_key_description(key, description)
+    local desc = {}
+    desc.key = key
+    desc.description = description
+    set_keyorder(desc, {'key', 'description'})
+    return desc
+end
+
+-- Sets the key order for the resulting JSON table
+function set_keyorder(table, order)
+    setmetatable(table, {
+        __jsonorder = order
+    })
+end
+
+
+-- Prints the collected tags in the required format in JSON
+function print_taginfo()
+    local tags = {}
+
+    for _, k in ipairs(flex.TAGINFO_MAIN.keys) do
+        local desc = get_key_description(k, 'POI/feature in the search database')
+        if flex.TAGINFO_MAIN.delete_tags[k] ~= nil then
+            desc.description = string.format('%s(except for values: %s).', desc.description,
+                                table.concat(flex.TAGINFO_MAIN.delete_tags[k], ', '))
+        end
+        table.insert(tags, desc)
+    end
+
+    for k, _ in pairs(flex.TAGINFO_NAME_KEYS) do
+        local desc = get_key_description(k, 'Searchable name of the place.')
+        table.insert(tags, desc)
+    end
+    for k, _ in pairs(flex.TAGINFO_ADDRESS_KEYS) do
+        local desc = get_key_description(k, 'Used to determine the address of a place.')
+        table.insert(tags, desc)
+    end
+
+    local format = {
+        data_format = 1,
+        data_url = 'http://nominatim.openstreetmap.org/taginfo.json',
+        project = {
+            name = 'Nominatim',
+            description = 'OSM search engine.',
+            project_url = 'http://nominatim.openstreetmap.org',
+            doc_url = 'http://wiki.osm.org/wiki/Nominatim',
+            contact_name = 'Sarah Hoffmann',
+            contact_email = 'lonvia@denofr.de'
+        }
+    }
+    format.tags = tags
+
+    set_keyorder(format, {'data_format', 'data_url', 'project', 'tags'})
+    set_keyorder(format.project, {'name', 'description', 'project_url', 'doc_url',
+                    'contact_name', 'contact_email'})
+
+    print(json.encode(format))
+end
+
+print_taginfo()