X-Git-Url: https://git.openstreetmap.org./nominatim.git/blobdiff_plain/3742fa2929619a4c54a50d3e79e0eeadb4d6ca6f..ae8694a6a6862d7cb66cd91102d2802c9899e7cf:/src/nominatim_db/db/connection.py diff --git a/src/nominatim_db/db/connection.py b/src/nominatim_db/db/connection.py index 629fad6a..e960a3fa 100644 --- a/src/nominatim_db/db/connection.py +++ b/src/nominatim_db/db/connection.py @@ -7,73 +7,28 @@ """ Specialised connection and cursor functions. """ -from typing import Optional, Any, Callable, ContextManager, Dict, cast, overload,\ - Tuple, Iterable -import contextlib +from typing import Optional, Any, Dict, Tuple import logging import os -import psycopg2 -import psycopg2.extensions -import psycopg2.extras -from psycopg2 import sql as pysql +import psycopg +import psycopg.types.hstore +from psycopg import sql as pysql -from ..typing import SysEnv, Query, T_cursor +from ..typing import SysEnv from ..errors import UsageError LOG = logging.getLogger() -class Cursor(psycopg2.extras.DictCursor): - """ A cursor returning dict-like objects and providing specialised - execution functions. - """ - # pylint: disable=arguments-renamed,arguments-differ - def execute(self, query: Query, args: Any = None) -> None: - """ Query execution that logs the SQL query when debugging is enabled. - """ - if LOG.isEnabledFor(logging.DEBUG): - LOG.debug(self.mogrify(query, args).decode('utf-8')) - - super().execute(query, args) - - - def execute_values(self, sql: Query, argslist: Iterable[Tuple[Any, ...]], - template: Optional[Query] = None) -> None: - """ Wrapper for the psycopg2 convenience function to execute - SQL for a list of values. - """ - LOG.debug("SQL execute_values(%s, %s)", sql, argslist) - - psycopg2.extras.execute_values(self, sql, argslist, template=template) - - -class Connection(psycopg2.extensions.connection): - """ A connection that provides the specialised cursor by default and - adds convenience functions for administrating the database. - """ - @overload # type: ignore[override] - def cursor(self) -> Cursor: - ... - - @overload - def cursor(self, name: str) -> Cursor: - ... - - @overload - def cursor(self, cursor_factory: Callable[..., T_cursor]) -> T_cursor: - ... +Cursor = psycopg.Cursor[Any] +Connection = psycopg.Connection[Any] - def cursor(self, cursor_factory = Cursor, **kwargs): # type: ignore - """ Return a new cursor. By default the specialised cursor is returned. - """ - return super().cursor(cursor_factory=cursor_factory, **kwargs) - -def execute_scalar(conn: Connection, sql: Query, args: Any = None) -> Any: +def execute_scalar(conn: Connection, sql: psycopg.abc.Query, args: Any = None) -> Any: """ Execute query that returns a single value. The value is returned. If the query yields more than one row, a ValueError is raised. """ - with conn.cursor() as cur: + with conn.cursor(row_factory=psycopg.rows.tuple_row) as cur: cur.execute(sql, args) if cur.rowcount != 1: @@ -88,9 +43,10 @@ def execute_scalar(conn: Connection, sql: Query, args: Any = None) -> Any: def table_exists(conn: Connection, table: str) -> bool: """ Check that a table with the given name exists in the database. """ - num = execute_scalar(conn, - """SELECT count(*) FROM pg_tables - WHERE tablename = %s and schemaname = 'public'""", (table, )) + num = execute_scalar( + conn, + """SELECT count(*) FROM pg_tables + WHERE tablename = %s and schemaname = 'public'""", (table, )) return num == 1 if isinstance(num, int) else False @@ -98,9 +54,9 @@ def table_has_column(conn: Connection, table: str, column: str) -> bool: """ Check if the table 'table' exists and has a column with name 'column'. """ has_column = execute_scalar(conn, - """SELECT count(*) FROM information_schema.columns - WHERE table_name = %s and column_name = %s""", - (table, column)) + """SELECT count(*) FROM information_schema.columns + WHERE table_name = %s and column_name = %s""", + (table, column)) return has_column > 0 if isinstance(has_column, int) else False @@ -123,8 +79,9 @@ def index_exists(conn: Connection, index: str, table: Optional[str] = None) -> b return True + def drop_tables(conn: Connection, *names: str, - if_exists: bool = True, cascade: bool = False) -> None: + if_exists: bool = True, cascade: bool = False) -> None: """ Drop one or more tables with the given names. Set `if_exists` to False if a non-existent table should raise an exception instead of just being ignored. `cascade` will cause @@ -144,7 +101,7 @@ def server_version_tuple(conn: Connection) -> Tuple[int, int]: """ Return the server version as a tuple of (major, minor). Converts correctly for pre-10 and post-10 PostgreSQL versions. """ - version = conn.server_version + version = conn.info.server_version if version < 100000: return (int(version / 10000), int((version % 10000) / 100)) @@ -164,31 +121,25 @@ def postgis_version_tuple(conn: Connection) -> Tuple[int, int]: return (int(version_parts[0]), int(version_parts[1])) + def register_hstore(conn: Connection) -> None: """ Register the hstore type with psycopg for the connection. """ - psycopg2.extras.register_hstore(conn) - - -class ConnectionContext(ContextManager[Connection]): - """ Context manager of the connection that also provides direct access - to the underlying connection. - """ - connection: Connection + info = psycopg.types.TypeInfo.fetch(conn, "hstore") + if info is None: + raise RuntimeError('Hstore extension is requested but not installed.') + psycopg.types.hstore.register_hstore(info, conn) -def connect(dsn: str) -> ConnectionContext: +def connect(dsn: str, **kwargs: Any) -> Connection: """ Open a connection to the database using the specialised connection factory. The returned object may be used in conjunction with 'with'. When used outside a context manager, use the `connection` attribute to get the connection. """ try: - conn = psycopg2.connect(dsn, connection_factory=Connection) - ctxmgr = cast(ConnectionContext, contextlib.closing(conn)) - ctxmgr.connection = conn - return ctxmgr - except psycopg2.OperationalError as err: + return psycopg.connect(dsn, row_factory=psycopg.rows.namedtuple_row, **kwargs) + except psycopg.OperationalError as err: raise UsageError(f"Cannot connect to database: {err}") from err @@ -233,10 +184,18 @@ def get_pg_env(dsn: str, """ env = dict(base_env if base_env is not None else os.environ) - for param, value in psycopg2.extensions.parse_dsn(dsn).items(): + for param, value in psycopg.conninfo.conninfo_to_dict(dsn).items(): if param in _PG_CONNECTION_STRINGS: - env[_PG_CONNECTION_STRINGS[param]] = value + env[_PG_CONNECTION_STRINGS[param]] = str(value) else: LOG.error("Unknown connection parameter '%s' ignored.", param) return env + + +async def run_async_query(dsn: str, query: psycopg.abc.Query) -> None: + """ Open a connection to the database and run a single query + asynchronously. + """ + async with await psycopg.AsyncConnection.connect(dsn) as aconn: + await aconn.execute(query)