By default xcom_pull assumes you're pulling from the same DAG ID. You can override this with the dag_id kwarg in xcom_pull. https://github.com/apache/incubator-airflow/blob/6ee4bbd4b1bc4b3f275f7946e2bcdd123970e2dd/airflow/models.py#L1829
best, Wilson On Wed, Jan 31, 2018 at 12:05 AM, Edward Tomazic <[email protected]> wrote: > Hi, > > Have a general question re the use of XCom between Sub > DAGs. > > > > I have the following DAG structure: > > > > dag.task-1 (SubDagOperator) > > subdag1.task-1 (PythonOperator) >> subdag1.task-2 (SubDagOperator) > > subdag2.task-3 > (BigQueryOperator) >> subdag2.task-4 (BigQueryOperator) > > > > subdag1.task-1 returns a value which is automatically pushed to XCom with > a key of “return_value”. I then try to pull the value from subdag2.task-3 > with the following template: > > > > {{ task_instance*.*xcom_pull(task_ids*=*'task-1', key*=*'return_value') }} > > > > The template returns the value “None”. > > > > Can XCom be used to communicate between tasks of different DAGs? And if > so, what am I doing wrong? > > > > Kind regards, > > > > *Edward Tomazic* > > Data W/H Solution Architect > > Scentre Group IT Data Management > ------------------------------ > > SCENTRE GROUP > > T > > +61 2 9358 7887 <+61%202%209358%207887> > > F > > +61 2 9028 8500 <+61%202%209028%208500> > > M > > +61 437 272 696 <+61%20437%20272%20696> > > E > > [email protected] > > FB > > Scentre Group <https://www.facebook.com/#!/Westfield?fref=ts> > > W > > scentregroup.com <http://www.scentregroup.com> > > > > [image: > https://res.cloudinary.com/scentre-group-au/image/upload/v1510274486/email/logo.jpg] > <http://www.scentregroup.com/> > > > > This e-mail may contain information which is confidential, subject to > legal privilege and /or protected by copyright. If you are not the intended > recipient (or have received this e-mail in error) please notify the sender > immediately and destroy all copies of this email. >
