Source code for airflow.providers.apache.cassandra.sensors.table

#
# 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 __future__ import annotations

from typing import TYPE_CHECKING, Any, Sequence

from airflow.providers.apache.cassandra.hooks.cassandra import CassandraHook
from airflow.sensors.base import BaseSensorOperator

if TYPE_CHECKING:
    from airflow.utils.context import Context


[docs]class CassandraTableSensor(BaseSensorOperator):
    """
    Checks for the existence of a table in a Cassandra cluster.

    .. seealso::
        For more information on how to use this operator, take a look at the guide:
        :ref:`howto/operator:CassandraTableSensor`


    For example, if you want to wait for a table called 't' to be created
    in a keyspace 'k', instantiate it as follows:

    >>> cassandra_sensor = CassandraTableSensor(
    ...     table="k.t", cassandra_conn_id="cassandra_default", task_id="cassandra_sensor"
    ... )

    :param table: Target Cassandra table.
        Use dot notation to target a specific keyspace.
    :param cassandra_conn_id: The connection ID to use
        when connecting to Cassandra cluster
    """

[docs]    template_fields: Sequence[str] = ("table",)

    def __init__(
        self,
        *,
        table: str,
        cassandra_conn_id: str = CassandraHook.default_conn_name,
        **kwargs: Any,
    ) -> None:
        super().__init__(**kwargs)
        self.cassandra_conn_id = cassandra_conn_id
        self.table = table

[docs]    def poke(self, context: Context) -> bool:
        self.log.info("Sensor check existence of table: %s", self.table)
        hook = CassandraHook(self.cassandra_conn_id)
        return hook.table_exists(self.table)