Simple Django User Session Clearing using Celery

7 months ago

1 min read

Django provides session support out-of-the-box and stores sessions in the django_session database table. Django leaves it up to the project maintainers to purge sessions in their Django project. This means that if it's not done on a regular basis the table grows infinitely. However, they provide a simple command called clearsessions for it. Using it within a Celery task in a cron schedule resolves any long-term storage issues with large tables for sessions. The below solution requires both Celery for the task and Celery-beat for the cron schedule.

config/celery_app.py

app.conf.beat_schedule = {
    # Clear expired sessions
    "clear_sessions": {
        "task": "config.celery_app.clear_sessions",
        "schedule": crontab(hour=0, minute=0, day_of_week=0),
    },
    ... other tasks
}

@app.task
def clear_sessions():
    """Clear expired sessions by using Django management command."""
    management.call_command("clearsessions")

Recently, the django_session table grew to a couple of gigabytes and I added this solution to clear the table. Now it's a default addition to any Django and Celery project.

django devops celery celery-beat