# Licensed to the Apache Software Foundation (ASF) under one # or more contributor license agreements. See the NOTICE file # distributed with this work for additional information # regarding copyright ownership. The ASF licenses this file # to you under the Apache License, Version 2.0 (the # "License"); you may not use this file except in compliance # with the License. You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, # software distributed under the License is distributed on an # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY # KIND, either express or implied. See the License for the # specific language governing permissions and limitations # under the License. from datetime import datetime from typing import Any, List, Optional, Tuple, TYPE_CHECKING from pytz import _FixedOffset # type: ignore from sqlalchemy.dialects.postgresql.base import PGInspector from superset.db_engine_specs.base import BaseEngineSpec from superset.utils import core as utils if TYPE_CHECKING: # pylint: disable=unused-import from superset.models.core import Database # pragma: no cover # Replace psycopg2.tz.FixedOffsetTimezone with pytz, which is serializable by PyArrow # https://github.com/stub42/pytz/blob/b70911542755aeeea7b5a9e066df5e1c87e8f2c8/src/pytz/reference.py#L25 class FixedOffsetTimezone(_FixedOffset): pass class PostgresBaseEngineSpec(BaseEngineSpec): """ Abstract class for Postgres 'like' databases """ engine = "" engine_name = "PostgreSQL" _time_grain_expressions = { None: "{col}", "PT1S": "DATE_TRUNC('second', {col})", "PT1M": "DATE_TRUNC('minute', {col})", "PT1H": "DATE_TRUNC('hour', {col})", "P1D": "DATE_TRUNC('day', {col})", "P1W": "DATE_TRUNC('week', {col})", "P1M": "DATE_TRUNC('month', {col})", "P0.25Y": "DATE_TRUNC('quarter', {col})", "P1Y": "DATE_TRUNC('year', {col})", } @classmethod def fetch_data(cls, cursor: Any, limit: int) -> List[Tuple[Any, ...]]: cursor.tzinfo_factory = FixedOffsetTimezone if not cursor.description: return [] return super().fetch_data(cursor, limit) @classmethod def epoch_to_dttm(cls) -> str: return "(timestamp 'epoch' + {col} * interval '1 second')" class PostgresEngineSpec(PostgresBaseEngineSpec): engine = "postgresql" max_column_name_length = 63 try_remove_schema_from_table_name = False @classmethod def get_table_names( cls, database: "Database", inspector: PGInspector, schema: Optional[str] ) -> List[str]: """Need to consider foreign tables for PostgreSQL""" tables = inspector.get_table_names(schema) tables.extend(inspector.get_foreign_table_names(schema)) return sorted(tables) @classmethod def convert_dttm(cls, target_type: str, dttm: datetime) -> Optional[str]: tt = target_type.upper() if tt == utils.TemporalType.DATE: return f"TO_DATE('{dttm.date().isoformat()}', 'YYYY-MM-DD')" if tt == utils.TemporalType.TIMESTAMP: return f"""TO_TIMESTAMP('{dttm.isoformat(sep=" ", timespec="microseconds")}', 'YYYY-MM-DD HH24:MI:SS.US')""" # pylint: disable=line-too-long return None