Add periodic jobs

[bschollnick]

Please add some sort of support for periodic jobs... For example:

TASKS = {
"default": {
"BACKEND": "dbtasks.backend.DatabaseBackend",
"OPTIONS": {
# How long to retain ScheduledTasks in the database. Forever if not set.
"retain": datetime.timedelta(days=7),
# Tasks to run periodically.
"periodic": {
# Runs at 3:30am every Monday through Friday.
"myproject.tasks.maintenance": "30 3 * * 1-5",
},
},
},
}

I am currently using a different tasks library, but I have 3 periodic jobs:

        "periodic": {
            "quickbbs.tasks.daily_cleanup_finished_jobs": Periodic("0 0 * * *"),
            "quickbbs.tasks.weekly_vacuum_check": Periodic("0 6 * * 0"),
            "quickbbs.tasks.check_ssl_cert_expiry": Periodic("0 6 * * *"),
        },

And I don't see anyway to duplicate this functionality via django-tasks-db.

[lairdresearch]

just a thought -- pg_cron is a thing in postgres. Maybe some combination of pg_cron and tasks_db (as an optional extra) might be interesting.

[bschollnick]

ust a thought -- pg_cron is a thing in postgres. Maybe some combination of pg_cron and tasks_db (as an optional extra) might be interesting.

Postgresql based cron is interesting, but I think that would prevent you from being able to run python based tasks on a schedule.

That's what I'm doing. Running database pruning, checking / warning against SSL cert expiration, etc.
While the database pruning might (?) be possible in the postgresql's cron? nothing else could.

[lairdresearch]

sorry -- I mean a solution for periodic jobs requires a clock/alarm. pg_cron brings cron jobs into postgres, so that could be the alarm. pg_cron would insert a row in the jobs table on a clock, which is picked up by the worker and executed. So having them work together (pg_cron & tasks-db).

[whyscream]

This would be interesting! For people not running postgresql, the use of pg_cron would of course be a loss. I did a quick read through the code that Django-q2 uses for scheduled tasks, that doesn't seem to be very hard and is basically just a for loop triggering a database query every now and then.

Ref:

• https://github.com/django-q2/django-q2/blob/master/django_q/scheduler.py#L24
• https://github.com/django-q2/django-q2/blob/master/django_q/cluster.py#L366