| # 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 List, Optional |
| |
| from sqlalchemy.engine.reflection import Inspector |
| |
| from superset.db_engine_specs.base import BaseEngineSpec |
| from superset.utils import core as utils |
| |
| |
| class ImpalaEngineSpec(BaseEngineSpec): |
| """Engine spec for Cloudera's Impala""" |
| |
| engine = "impala" |
| engine_name = "Apache Impala" |
| |
| _time_grain_expressions = { |
| None: "{col}", |
| "PT1M": "TRUNC({col}, 'MI')", |
| "PT1H": "TRUNC({col}, 'HH')", |
| "P1D": "TRUNC({col}, 'DD')", |
| "P1W": "TRUNC({col}, 'WW')", |
| "P1M": "TRUNC({col}, 'MONTH')", |
| "P0.25Y": "TRUNC({col}, 'Q')", |
| "P1Y": "TRUNC({col}, 'YYYY')", |
| } |
| |
| @classmethod |
| def epoch_to_dttm(cls) -> str: |
| return "from_unixtime({col})" |
| |
| @classmethod |
| def convert_dttm(cls, target_type: str, dttm: datetime) -> Optional[str]: |
| tt = target_type.upper() |
| if tt == utils.TemporalType.DATE: |
| return f"CAST('{dttm.date().isoformat()}' AS DATE)" |
| if tt == utils.TemporalType.TIMESTAMP: |
| return f"""CAST('{dttm.isoformat(timespec="microseconds")}' AS TIMESTAMP)""" |
| return None |
| |
| @classmethod |
| def get_schema_names(cls, inspector: Inspector) -> List[str]: |
| schemas = [ |
| row[0] |
| for row in inspector.engine.execute("SHOW SCHEMAS") |
| if not row[0].startswith("_") |
| ] |
| return schemas |