Add quarterly to crontab presets (apache#6873)

Author: zhongjiajie

airflow/utils/dates.py

@@ -34,6 +34,7 @@
     '@daily': '0 0 * * *',
     '@weekly': '0 0 * * 0',
     '@monthly': '0 0 1 * *',
+    '@quarterly': '0 0 1 */3 *',
     '@yearly': '0 0 1 1 *',
 }
 

docs/scheduler.rst

@@ -64,24 +64,26 @@ preferably a
 a ``str``, or a ``datetime.timedelta`` object. Alternatively, you can also
 use one of these cron "preset":
 
-+--------------+----------------------------------------------------------------+---------------+
-| preset       | meaning                                                        | cron          |
-+==============+================================================================+===============+
-| ``None``     | Don't schedule, use for exclusively "externally triggered"     |               |
-|              | DAGs                                                           |               |
-+--------------+----------------------------------------------------------------+---------------+
-| ``@once``    | Schedule once and only once                                    |               |
-+--------------+----------------------------------------------------------------+---------------+
-| ``@hourly``  | Run once an hour at the beginning of the hour                  | ``0 * * * *`` |
-+--------------+----------------------------------------------------------------+---------------+
-| ``@daily``   | Run once a day at midnight                                     | ``0 0 * * *`` |
-+--------------+----------------------------------------------------------------+---------------+
-| ``@weekly``  | Run once a week at midnight on Sunday morning                  | ``0 0 * * 0`` |
-+--------------+----------------------------------------------------------------+---------------+
-| ``@monthly`` | Run once a month at midnight of the first day of the month     | ``0 0 1 * *`` |
-+--------------+----------------------------------------------------------------+---------------+
-| ``@yearly``  | Run once a year at midnight of January 1                       | ``0 0 1 1 *`` |
-+--------------+----------------------------------------------------------------+---------------+
++----------------+----------------------------------------------------------------+-----------------+
+| preset         | meaning                                                        | cron            |
++================+================================================================+=================+
+| ``None``       | Don't schedule, use for exclusively "externally triggered"     |                 |
+|                | DAGs                                                           |                 |
++----------------+----------------------------------------------------------------+-----------------+
+| ``@once``      | Schedule once and only once                                    |                 |
++----------------+----------------------------------------------------------------+-----------------+
+| ``@hourly``    | Run once an hour at the beginning of the hour                  | ``0 * * * *``   |
++----------------+----------------------------------------------------------------+-----------------+
+| ``@daily``     | Run once a day at midnight                                     | ``0 0 * * *``   |
++----------------+----------------------------------------------------------------+-----------------+
+| ``@weekly``    | Run once a week at midnight on Sunday morning                  | ``0 0 * * 0``   |
++----------------+----------------------------------------------------------------+-----------------+
+| ``@monthly``   | Run once a month at midnight of the first day of the month     | ``0 0 1 * *``   |
++----------------+----------------------------------------------------------------+-----------------+
+| ``@quarterly`` | Run once a quarter at midnight on the first day                | ``0 0 1 */3 *`` |
++----------------+----------------------------------------------------------------+-----------------+
+| ``@yearly``    | Run once a year at midnight of January 1                       | ``0 0 1 1 *``   |
++----------------+----------------------------------------------------------------+-----------------+
 
 **Note**: Use ``schedule_interval=None`` and not ``schedule_interval='None'`` when
 you don't want to schedule your DAG.