feature request: cron job

[HonkXL]

At moment users visiting the site are triggering events like sending of update-mails (in the language of visitor, not user) or mails about open reviews.
I think it would be a good idea to make a setting where the admin can change it between "event triggered by visitor" and "event triggered by cron job". On the second option you have to manually add a cron job on the OS.

The advantage would be that mails are sent on a useful time sheme like all 6 hours and update checks can be performed on fixed hours, not random.

If you know Nextcloud - there this is an option to run the background jobs by
AJAX (triggered by visitor/user)
Webcron (webcron is starting cron.php over http - only for small installations)
Cron (cron is calling php ./occ in context of the www-data user - this is the recommended way).

And there is a view when the last cron job was running and a error when this time was too long in the past.

And maybe this cron job could be used for things like sheduled exports, database reorgs or automated cleanups in the future?

[mpaluchowski]

Seconded. This should also help implement #2948 because the cron job could also check for updates. Wordpress does this with its wp-cron.