Source code for airflow.operators.subdag_operator

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from airflow import settings
from airflow.exceptions import AirflowException
from airflow.executors.sequential_executor import SequentialExecutor
from airflow.models import BaseOperator, Pool
from airflow.utils.decorators import apply_defaults
from airflow.utils.db import provide_session

[docs]class SubDagOperator(BaseOperator): """ This runs a sub dag. By convention, a sub dag's dag_id should be prefixed by its parent and a dot. As in `parent.child`. :param subdag: the DAG object to run as a subdag of the current DAG. :type subdag: airflow.models.DAG :param dag: the parent DAG for the subdag. :type dag: airflow.models.DAG :param executor: the executor for this subdag. Default to use SequentialExecutor. Please find AIRFLOW-74 for more details. :type executor: airflow.executors.base_executor.BaseExecutor """
[docs] ui_color = '#555'
[docs] ui_fgcolor = '#fff'
@provide_session @apply_defaults def __init__( self, subdag, executor=SequentialExecutor(), *args, **kwargs): dag = kwargs.get('dag') or settings.CONTEXT_MANAGER_DAG if not dag: raise AirflowException('Please pass in the `dag` param or call ' 'within a DAG context manager') session = kwargs.pop('session') super(SubDagOperator, self).__init__(*args, **kwargs) # validate subdag name if dag.dag_id + '.' + kwargs['task_id'] != subdag.dag_id: raise AirflowException( "The subdag's dag_id should have the form " "'{{parent_dag_id}}.{{this_task_id}}'. Expected " "'{d}.{t}'; received '{rcvd}'.".format( d=dag.dag_id, t=kwargs['task_id'], rcvd=subdag.dag_id)) # validate that subdag operator and subdag tasks don't have a # pool conflict if self.pool: conflicts = [t for t in subdag.tasks if t.pool == self.pool] if conflicts: # only query for pool conflicts if one may exist pool = ( session .query(Pool) .filter(Pool.slots == 1) .filter(Pool.pool == self.pool) .first() ) if pool and any(t.pool == self.pool for t in subdag.tasks): raise AirflowException( 'SubDagOperator {sd} and subdag task{plural} {t} both ' 'use pool {p}, but the pool only has 1 slot. The ' 'subdag tasks will never run.'.format( sd=self.task_id, plural=len(conflicts) > 1, t=', '.join(t.task_id for t in conflicts), p=self.pool ) ) self.subdag = subdag # Airflow pool is not honored by SubDagOperator. # Hence resources could be consumed by SubdagOperators # Use other executor with your own risk. self.executor = executor
[docs] def execute(self, context): ed = context['execution_date'] start_date=ed, end_date=ed, donot_pickle=True, executor=self.executor)

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