Source code for airflow.providers.apache.hive.sensors.metastore_partition

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from __future__ import annotations

from typing import TYPE_CHECKING, Any, Sequence

from airflow.providers.common.sql.sensors.sql import SqlSensor

if TYPE_CHECKING:
    from airflow.utils.context import Context


[docs]class MetastorePartitionSensor(SqlSensor): """ An alternative to the HivePartitionSensor that talk directly to the MySQL db. This was created as a result of observing sub optimal queries generated by the Metastore thrift service when hitting subpartitioned tables. The Thrift service's queries were written in a way that would not leverage the indexes. :param schema: the schema :param table: the table :param partition_name: the partition name, as defined in the PARTITIONS table of the Metastore. Order of the fields does matter. Examples: ``ds=2016-01-01`` or ``ds=2016-01-01/sub=foo`` for a sub partitioned table :param mysql_conn_id: a reference to the MySQL conn_id for the metastore """
[docs] template_fields: Sequence[str] = ("partition_name", "table", "schema")
[docs] ui_color = "#8da7be"
def __init__( self, *, table: str, partition_name: str, schema: str = "default", mysql_conn_id: str = "metastore_mysql", **kwargs: Any, ): self.partition_name = partition_name self.table = table self.schema = schema self.first_poke = True self.conn_id = mysql_conn_id # TODO(aoen): We shouldn't be using SqlSensor here but MetastorePartitionSensor. # The problem is the way apply_defaults works isn't compatible with inheritance. # The inheritance model needs to be reworked in order to support overriding args/ # kwargs with arguments here, then 'conn_id' and 'sql' can be passed into the # constructor below and apply_defaults will no longer throw an exception. super().__init__(**kwargs)
[docs] def poke(self, context: Context) -> Any: if self.first_poke: self.first_poke = False if "." in self.table: self.schema, self.table = self.table.split(".") self.sql = f""" SELECT 'X' FROM PARTITIONS A0 LEFT OUTER JOIN TBLS B0 ON A0.TBL_ID = B0.TBL_ID LEFT OUTER JOIN DBS C0 ON B0.DB_ID = C0.DB_ID WHERE B0.TBL_NAME = '{self.table}' AND C0.NAME = '{self.schema}' AND A0.PART_NAME = '{self.partition_name}'; """ return super().poke(context)

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