rq-rediscron 0.1.2

Redis-backed runtime-editable cron scheduler for RQ

rq-rediscron

rq-rediscron provides Redis-backed subclasses for RQ cron scheduling:

• RedisCronJob
• RedisCronScheduler

Cron job definitions are stored in Redis hashes and indexed in a sorted set by next enqueue time. This lets scheduler processes pick up job creates, edits, and deletes at runtime without restart.

Only one RedisCronScheduler process runs at a time. The scheduler acquires rq:cron_jobs:lock during register_birth(), extends that lock on heartbeat, and releases it during register_death(). A second scheduler can start after the lock TTL expires, which provides failover without duplicate enqueue loops.

from redis import Redis
from rediscron import RedisCronScheduler


def rebuild_metric(metric_id: str) -> None:
    ...


connection = Redis.from_url("redis://localhost:6379/0")
scheduler = RedisCronScheduler(connection)
scheduler.register(
    rebuild_metric,
    queue_name="metrics",
    id="metric:pm25",
    args=("pm25",),
    interval=300,
)
scheduler.start()

Redis keys:

• rq:cron_job:{id} stores one cron job hash.
• rq:cron_jobs indexes job ids by next enqueue timestamp.
• rq:cron_jobs:lock allows one live scheduler process at a time.
• rq:cron_jobs:last_update records runtime changes.
• rq:cron_jobs:events publishes create, update, and delete events.