python - Airflow default on_failure_callback -

in dag file, have define on_failure_callback() function post slack in case of failure.

it works if specify each operator in dag : on_failure_callback=on_failure_callback()

is there way automate (via default_args instance, or via dag object) dispatch of operators?

i found way that.

you can pass on_failure_callback default_args

class foo:   @staticmethod   def get_default_args():       """       return default args       :return: default_args       """        default_args = {           'on_failure_callback': foo.on_failure_callback       }        return default_args    @staticmethod   def on_failure_callback(context):      """      define callback post on slack if failure detected in workflow      :return: operator.execute      """       operator = slackapipostoperator(          task_id='failure',          text=str(context['task_instance']),          token=variable.get("slack_access_token"),          channel=variable.get("slack_channel")      )       return operator.execute(context=context)