django_cron doesn't seem to lock task

Question

I'm using django 1.10 and the django_cron package (0.5.0).

That package suppose to lock the task while it's running by default, so it won't be running on other servers. Seems like in our project (that hosted on 3 servers) - it runs 3 times every hour (that's the schedule) I didn't change anything in the configuration as I understand it should lock tasks by default.

This is the task:

class CreateMissingItems(CronJobBase):
    RUN_EVERY_MINS = 60

    schedule = Schedule(run_every_mins=RUN_EVERY_MINS)
    code = 'CreateMissingItems'  # a unique id

    def do(self):
        MyLog().info(message="Starting scheduled task of creating missing items")
        call_command('create_missing_items')

crontab task is running basically every 20 minutes. Am I missing anything?

Answer 1

You need to implement a shared lock. The package provides a database shared lock that you can configure by adding the following line to settings.py:

DJANGO_CRON_LOCK_BACKEND = 'django_cron.backends.lock.database.DatabaseLock'