[jira] [Commented] (AIRFLOW-2923) LatestOnlyOperator cascade skip through all_done and dummy

["ASF GitHub Bot (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/AIRFLOW-2923?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16904526#comment-16904526 ] 

ASF GitHub Bot commented on AIRFLOW-2923:
-----------------------------------------

m1racoli commented on pull request #5778: [AIRFLOW-2923][AIRFLOW-1784] Let operators inherit from BaseBranchOperator
URL: https://github.com/apache/airflow/pull/5778
 
 
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   ### Description
   
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   LatestOnlyOperator is a special case of a BranchOperator, thus it should inherit from it.
   This fixes an issue where the skipping behaviour of LatestOnlyOperator is inconsistent with other operators by forcefully skipping all downstream tasks recursively, ignoring trigger rules.
   In addition BranchPythonOperator should inherit from BaseBranchOperator as well.
   
   ### Tests
   
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   Extended `tests.operators.test_latest_only_operator.py` to cover downstream children with trigger rules.
   
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> LatestOnlyOperator cascade skip through all_done and dummy
> ----------------------------------------------------------
>
>                 Key: AIRFLOW-2923
>                 URL: https://issues.apache.org/jira/browse/AIRFLOW-2923
>             Project: Apache Airflow
>          Issue Type: Bug
>          Components: scheduler
>    Affects Versions: 1.9.0
>         Environment: CeleryExecutor, 2-nodes cluster, RMQ, PostgreSQL
>            Reporter: Dmytro Kulyk
>            Assignee: Cedrik Neumann
>            Priority: Major
>              Labels: cascade, latestonly, skip
>         Attachments: cube_update.py, screenshot-1.png
>
>
> DAG with consolidating point (calc_ready : dummy)
> as per [https://airflow.apache.org/concepts.html#latest-run-only] given task should be ran even catching up an execution DagRuns for a previous periods
>  However, LatestOnlyOperator cascading through calc_ready despite of it is a dummy and trigger_rule=all_done
>  Same behavior when trigger_rule=all_success
> {code}
> t_ready = DummyOperator(
>   task_id = 'calc_ready',
>   trigger_rule = TriggerRule.ALL_DONE,
>   dag=dag)
> {code}
> !screenshot-1.png!



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