Source code for airflow.contrib.sensors.cassandra_table_sensor

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from airflow.contrib.hooks.cassandra_hook import CassandraHook
from airflow.sensors.base_sensor_operator import BaseSensorOperator
from airflow.utils.decorators import apply_defaults


[docs]class CassandraTableSensor(BaseSensorOperator): """ Checks for the existence of a table in a Cassandra cluster. 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") """ template_fields = ('table',) @apply_defaults def __init__(self, table, cassandra_conn_id, *args, **kwargs): """ Create a new CassandraTableSensor :param table: Target Cassandra table. Use dot notation to target a specific keyspace. :type table: string :param cassandra_conn_id: The connection ID to use when connecting to Cassandra cluster :type cassandra_conn_id: string """ super(CassandraTableSensor, self).__init__(*args, **kwargs) self.cassandra_conn_id = cassandra_conn_id self.table = table
[docs] def poke(self, context): self.log.info('Sensor check existence of table: %s', self.table) hook = CassandraHook(self.cassandra_conn_id) return hook.table_exists(self.table)