save software version in the database

The version represents the software version that was used to
import the data.

nominatim/clicmd/setup.py

@@ -8,7 +8,8 @@ import psutil
 
 from ..tools.exec_utils import run_legacy_script
 from ..db.connection import connect
-from ..db import status
+from ..db import status, properties
+from ..version import NOMINATIM_VERSION
 from ..errors import UsageError
 
 # Do not repeat documentation of subcommand classes.
@@ -140,4 +141,7 @@ class SetupAll:
             except Exception as exc: # pylint: disable=broad-except
                 LOG.error('Cannot determine date of database: %s', exc)
 
+            properties.set_property(conn, 'database_version',
+                                    '{0[0]}.{0[1]}.{0[2]}-{0[3]}'.format(NOMINATIM_VERSION))
+
         return 0

nominatim/db/properties.py

@@ -0,0 +1,28 @@
+"""
+Query and access functions for the in-database property table.
+"""
+
+def set_property(conn, name, value):
+    """ Add or replace the propery with the given name.
+    """
+    with conn.cursor() as cur:
+        cur.execute('SELECT value FROM nominatim_properties WHERE property = %s',
+                    (name, ))
+
+        if cur.rowcount == 0:
+            sql = 'INSERT INTO nominatim_properties (value, property) VALUES (%s, %s)'
+        else:
+            sql = 'UPDATE nominatim_properties SET value = %s WHERE property = %s'
+
+        cur.execute(sql, (value, name))
+    conn.commit()
+
+def get_property(conn, name):
+    """ Return the current value of the given propery or None if the property
+        is not set.
+    """
+    with conn.cursor() as cur:
+        cur.execute('SELECT value FROM nominatim_properties WHERE property = %s',
+                    (name, ))
+
+        return cur.fetchone()[0] if cur.rowcount > 0 else None

test/python/test_db_connection.py

@@ -78,6 +78,14 @@ def test_cursor_scalar_many_rows(db):
             cur.scalar('SELECT * FROM pg_tables')
 
 
+def test_cursor_scalar_no_rows(db, table_factory):
+    table_factory('dummy')
+
+    with db.cursor() as cur:
+        with pytest.raises(RuntimeError):
+            cur.scalar('SELECT id FROM dummy')
+
+
 def test_get_pg_env_add_variable(monkeypatch):
     monkeypatch.delenv('PGPASSWORD', raising=False)
     env = get_pg_env('user=fooF')

test/python/test_db_properties.py

@@ -0,0 +1,35 @@
+"""
+Tests for property table manpulation.
+"""
+import pytest
+
+from nominatim.db import properties
+
+@pytest.fixture
+def prop_table(table_factory):
+    table_factory('nominatim_properties', 'property TEXT, value TEXT')
+
+
+def test_get_property_existing(prop_table, temp_db_conn, temp_db_cursor):
+    temp_db_cursor.execute("INSERT INTO nominatim_properties VALUES('foo', 'bar')")
+
+    assert properties.get_property(temp_db_conn, 'foo') == 'bar'
+
+
+def test_get_property_unknown(prop_table, temp_db_conn, temp_db_cursor):
+    temp_db_cursor.execute("INSERT INTO nominatim_properties VALUES('other', 'bar')")
+
+    assert properties.get_property(temp_db_conn, 'foo') is None
+
+
+@pytest.mark.parametrize("prefill", (True, False))
+def test_set_property_new(prop_table, temp_db_conn, temp_db_cursor, prefill):
+    if prefill:
+        temp_db_cursor.execute("INSERT INTO nominatim_properties VALUES('something', 'bar')")
+
+    properties.set_property(temp_db_conn, 'something', 'else')
+
+    assert temp_db_cursor.scalar("""SELECT value FROM nominatim_properties
+                                    WHERE property = 'something'""") == 'else'
+
+    assert properties.get_property(temp_db_conn, 'something') == 'else'