问题
Is it possible to get the actual start time of a dag in Airflow? By start time I mean the exact time the first task of a dag starts running.
I know I can use macros to get the execution date. If the job is ran using trigger_dag this is what I would call a start time but if the job is ran on a daily schedule then {{ execution_date }} returns yesterdays date.
I have also tried to place datetime.now().isoformat() in the body of the dag code and then pass it to a task but this seems to return the time the task is first called rather than when the dag itself started.
回答1:
{{ dag_run.start_date }} provides the actual start time of the dag
回答2:
I am following the way as you stated:
By start time I mean the exact time the first task of a dag starts running
You can still do this with macros on your first task, try this {{ task.start_date }}
All the variables can be found in TaskInstance class: https://github.com/apache/incubator-airflow/blob/master/airflow/models.py#L746
来源：https://stackoverflow.com/questions/47096829/airflow-get-start-time-of-dag-run