Gerben Oostra created AIRFLOW-5623: -------------------------------------- Summary: latest_only_operator fails for schedule_interval='@once' Key: AIRFLOW-5623 URL: https://issues.apache.org/jira/browse/AIRFLOW-5623 Project: Apache Airflow Issue Type: Bug Components: operators Affects Versions: 1.10.5 Reporter: Gerben Oostra
Observation: In a dag with schedule_interval set to @once, the `latest_only_operator` fails with the following error: {{[2019-10-09 09:51:37,346] \{latest_only_operator.py:48} INFO - Checking latest only with left_window: None right_window: None now: 2019-10-09 07:51:37.346697+00:00 [2019-10-09 09:51:37,347] \{models.py:1736} ERROR - '<' not supported between instances of 'NoneType' and 'datetime.datetime' Traceback (most recent call last): File "/XXXX/anaconda/envs/airflow/lib/python3.6/site-packages/airflow/models.py", line 1633, in _run_raw_task result = task_copy.execute(context=context) File "/XXXX/anaconda/envs/airflow/lib/python3.6/site-packages/airflow/operators/latest_only_operator.py", line 51, in execute if not left_window < now <= right_window: TypeError: '<' not supported between instances of 'NoneType' and 'datetime.datetime' [2019-10-09 09:51:37,363] \{models.py:1756} INFO - Marking task as UP_FOR_RETRY}} I expected it to succeed, and allow the remainder of the dag to be ran. (if an @once dag is running, it is always the latest) Rootcause analysis: If the `schedule_interval` of a dag is `@once`, the dag's field `self._schedule_interval` is set to `None`. The `latest_only_operator` determines the window by passing the execution date to the dags `following_schedule()`. There the dag's `self._schedule_interval` type is compared to `six.string_types` and `timedelta`. Both type checks fail, so nothing (`None`) is returned. Causing the time window comparison to fail. -- This message was sent by Atlassian Jira (v8.3.4#803005)