RQ (Redis Queue) is a simple Python library for queueing jobs and processing them in the background with workers. It is backed by Redis and it is designed to have a low barrier to entry. It can be integrated in your web stack easily.
RQ requires Redis >= 3.0.0.
First, run a Redis server. You can use an existing one. To put jobs on queues, you don’t have to do anything special, just define your typically lengthy or blocking function:
import requests def count_words_at_url(url): resp = requests.get(url) return len(resp.text.split())
Then, create a RQ queue:
from redis import Redis from rq import Queue q = Queue(connection=Redis())
And enqueue the function call:
from my_module import count_words_at_url result = q.enqueue(count_words_at_url, 'http://nvie.com')
Scheduling jobs are similarly easy:
# Schedule job to run at 9:15, October 10th job = queue.enqueue_at(datetime(2019, 10, 8, 9, 15), say_hello) # Schedule job to be run in 10 seconds job = queue.enqueue_in(timedelta(seconds=10), say_hello)
You can also ask RQ to retry failed jobs:
from rq import Retry # Retry up to 3 times, failed job will be requeued immediately queue.enqueue(say_hello, retry=Retry(max=3)) # Retry up to 3 times, with configurable intervals between retries queue.enqueue(say_hello, retry=Retry(max=3, interval=[10, 30, 60]))
To start executing enqueued function calls in the background, start a worker from your project’s directory:
$ rq worker --with-scheduler *** Listening for work on default Got count_words_at_url('http://nvie.com') from default Job result = 818 *** Listening for work on default
That’s about it.
Simply use the following command to install the latest released version:
pip install rq
If you want the cutting edge version (that may well be broken), use this:
pip install git+https://github.com/nvie/rq.git@master#egg=rq
This project has been inspired by the good parts of Celery, Resque and this snippet, and has been created as a lightweight alternative to existing queueing frameworks, with a low barrier to entry.