气流：DAG标记为“成功”；如果一项任务失败，由于触发规则ALL

本文介绍了气流：DAG标记为“成功”；如果一项任务失败，由于触发规则ALL_DONE的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我有以下3个任务的DAG：

I have the following DAG with 3 tasks :

start --> special_task --> end

中间任务可以成功或失败，但结束 必须总是被执行（想象这是清理资源的任务）。为此，我使用了触发规则 ALL_DONE ：

The task in the middle can succeed or fail, but end must always be executed (imagine this is a task for cleanly closing resources). For that, I used the trigger rule ALL_DONE :

end.trigger_rule = trigger_rule.TriggerRule.ALL_DONE

如果在以下情况下正确执行 end 特殊任务失败。但是，由于 end 是最后一个任务并且成功完成，因此DAG始终标记为 SUCCESS 。

Using that, end is properly executed if special_task fails. However, since end is the last task and succeeds, the DAG is always marked as SUCCESS.

如何配置DAG，以便如果其中一项任务失败，则整个DAG都标记为 FAILED ？

How can I configure my DAG so that if one of the tasks failed, the whole DAG is marked as FAILED?

import datetime from airflow import DAG from airflow.operators.bash_operator import BashOperator from airflow.utils import trigger_rule dag = DAG( dag_id='my_dag', start_date=datetime.datetime.today(), schedule_interval=None ) start = BashOperator( task_id='start', bash_command='echo start', dag=dag ) special_task = BashOperator( task_id='special_task', bash_command='exit 1', # force failure dag=dag ) end = BashOperator( task_id='end', bash_command='echo end', dag=dag ) end.trigger_rule = trigger_rule.TriggerRule.ALL_DONE start.set_downstream(special_task) special_task.set_downstream(end)

这篇文章似乎相关，但是答案不符合我的需要，因为必须执行下游任务 end （因此，强制性 trigger_rule ）。

This post seems to be related, but the answer does not suit my needs, since the downstream task end must be executed (hence the mandatory trigger_rule).

推荐答案

为@JustinasMarozas 在评论，一种解决方案是创建一个虚拟任务，例如：

As @JustinasMarozas explained in a comment, a solution is to create a dummy task like :

dummy = DummyOperator( task_id='test', dag=dag )

并将其下游绑定到 special_task ：

failing_task.set_downstream(dummy)

因此，DAG被标记为失败，并且 dummy 任务被标记为 upstream_failed 。

Thus, the DAG is marked as failed, and the dummy task is marked as upstream_failed.

希望在那里是一个开箱即用的解决方案，但请耐心等待，此解决方案可以完成工作。

Hope there is an out-of-the-box solution, but waiting for that, this solution does the job.