Airflow does not backfill latest run

Question

For some reason, Airflow doesn\'t seem to trigger the latest run for a dag with a weekly schedule interval.

Current Date:

$ date
$ Tue Aug  9 17:09:5         


        

Answer 1

Airflow always schedules for the previous period. So if you have a dag that is scheduled to run daily, on Aug 9th, it will schedule a run with execution_date Aug 8th. Similarly if the schedule interval is weekly, then on Aug 9th, it will schedule for 1 week back i.e. Aug 2nd, though this gets run on Aug 9th itself. This is just airflow bookkeeping. You can find this in the airflow wiki (https://cwiki.apache.org/confluence/display/AIRFLOW/Common+Pitfalls):

Understanding the execution date Airflow was developed as a solution for ETL needs. In the ETL world, you typically summarize data. So, if I want to summarize data for 2016-02-19, I would do it at 2016-02-20 midnight GMT, which would be right after all data for 2016-02-19 becomes available. This date is available to you in both Jinja and a Python callable's context in many forms as documented here. As a note ds refers to date_string, not date start as may be confusing to some.