Thx Boris . Credit goes to George (gwax) for the implementation of the LatestOnlyOperator.
Boris, Can you describe what you mean in a Jira? -s On Fri, Mar 17, 2017 at 6:02 PM, Boris Tyukin <[email protected]> wrote: > this is nice indeed along with the new catchup option > https://airflow.incubator.apache.org/scheduler.html#backfill-and-catchup > > Thanks Sid and Ben for adding these new options! > > for a complete picture, it would be nice to force only one dag run at the > time. > > On Fri, Mar 17, 2017 at 7:33 PM, siddharth anand <[email protected]> > wrote: > > > With the Apache Airflow 1.8 release imminent, you may want to try out the > > > > *LatestOnlyOperator.* > > > > If you want your DAG to only run on the most recent scheduled slot, > > regardless of backlog, this operator will skip running downstream tasks > for > > all DAG Runs prior to the current time slot. > > > > For example, I might have a DAG that takes a DB snapshot once a day. It > > might be that I paused that DAG for 2 weeks or that I had set the start > > date to a fixed data 2 weeks in the past. When I enable my DAG, I don't > > want it to run 14 days' worth of snapshots for the current state of the > DB > > -- that's unnecessary work. > > > > The LatestOnlyOperator avoids that work. > > > > https://github.com/apache/incubator-airflow/commit/ > > edf033be65b575f44aa221d5d0ec9ecb6b32c67a > > > > With it, you can simply use > > latest_only = LatestOnlyOperator(task_id='latest_only', dag=dag) > > > > instead of > > def skip_to_current_job(ds, **kwargs): > > now = datetime.now() > > left_window = kwargs['dag'].following_schedule(kwargs['execution_ > > date']) > > right_window = kwargs['dag'].following_schedule(left_window) > > logging.info(('Left Window {}, Now {}, Right Window > > {}').format(left_window,now,right_window)) > > if not now <= right_window: > > logging.info('Not latest execution, skipping downstream.') > > return False > > return True > > > > short_circuit = ShortCircuitOperator( > > task_id = 'short_circuit_if_not_current_job', > > provide_context = True, > > python_callable = skip_to_current_job, > > dag = dag > > ) > > > > -s > > >
