RQ (Redis Queue) is a lightweight^* Python library for queueing jobs and processing them in the background with workers. It is backed by Redis and it is extremely simple to use.

^* It is under 20 kB in size and just over 500 lines of code.

Getting started

First, run a Redis server, of course:

$ redis-server

To put jobs on queues, you don't have to do anything special, just define your typically lengthy or blocking function:

import urllib2

def count_words_at_url(url):
    f = urllib2.urlopen(url)
    count = 0
    while True:
        line = f.readline()
        if not line:
            break
        count += len(line.split())
    return count

Then, create a RQ queue:

import rq import *
use_redis()
q = Queue()

And enqueue the function call:

from my_module import count_words_at_url
result = q.enqueue(count_words_at_url, 'http://nvie.com')

For a more complete example, refer to the docs. But this is the essence.

The worker

To start executing enqueued function calls in the background, start a worker from your project's directory:

$ rqworker
*** 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.

Installation

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 -e git+git@github.com:nvie/rq.git@master#egg=rq

Project history

This project has been inspired by the good parts of Celery, Resque and this snippet, and has been created as a lightweight alternative to the heaviness of Celery or other AMQP-based queueing implementations.