incubator-superset0.99/superset/db_engine_specs/druid.py

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from typing import TYPE_CHECKING

from superset.db_engine_specs.base import BaseEngineSpec

if TYPE_CHECKING:
    from superset.connectors.sqla.models import (  # pylint: disable=unused-import
        TableColumn,
    )


class DruidEngineSpec(BaseEngineSpec):  # pylint: disable=abstract-method
    """Engine spec for Druid.io"""

    engine = "druid"
    allows_joins = False
    allows_subqueries = True

    _time_grain_functions = {
        None: "{col}",
        "PT1S": "FLOOR({col} TO SECOND)",
        "PT1M": "FLOOR({col} TO MINUTE)",
        "PT1H": "FLOOR({col} TO HOUR)",
        "P1D": "FLOOR({col} TO DAY)",
        "P1W": "FLOOR({col} TO WEEK)",
        "P1M": "FLOOR({col} TO MONTH)",
        "P0.25Y": "FLOOR({col} TO QUARTER)",
        "P1Y": "FLOOR({col} TO YEAR)",
    }

    @classmethod
    def alter_new_orm_column(cls, orm_col: "TableColumn") -> None:
        if orm_col.column_name == "__time":
            orm_col.is_dttm = True