Please note that catchup_by_default is True by default. Imagine what will happen if you set these start_date to fixed dates ;-)
XD On Fri, May 10, 2019 at 3:34 PM Jiajie Zhong <[email protected]> wrote: > Hi Airflowers: > I start this thread proposal to change all example_dags's start_date > to specific datetime, including airflow/example_dag and > airflow/contrib/example_dags. > I proposal that because in > https://airflow.apache.org/faq.html#what-s-the-deal-with-start-date > > > We recommend against using dynamic values as start_date, especially > datetime.now() as it can be quite confusing. The task is triggered once the > period closes, and in theory an @hourly DAG would never get to an hour > after now as now() moves along. > > we suggest to set start_date to specific datetime, but all example_dags in > code base are use dynamic values like `airflow.utils.dates.days_ago(2)` or > `datetime.utcnow()`. Most of Airflow starter will use example dag as they > template to create their own dag, so I think should change them in correct > values. > > But if we use a specific datetime in example dag, for example 2019-01-01, > starter will use them as template and confuse "Why my dag start run in > 2019-01-01?". > > So, should we change start_date? > > Best wish. > -- Jiajie >
