+def _require_loaded(extension_name: str, conn: Connection) -> None:
+ """ Check that the given extension is loaded. """
+ if not conn.extension_loaded(extension_name):
+ LOG.fatal('Required module %s is not loaded.', extension_name)
+ raise UsageError(f'{extension_name} is not loaded.')
+
+
+def check_existing_database_plugins(dsn: str) -> None:
+ """ Check that the database has the required plugins installed."""
+ with connect(dsn) as conn:
+ _require_version('PostgreSQL server',
+ conn.server_version_tuple(),
+ POSTGRESQL_REQUIRED_VERSION)
+ _require_version('PostGIS',
+ conn.postgis_version_tuple(),
+ POSTGIS_REQUIRED_VERSION)
+ _require_loaded('hstore', conn)
+
+