rq/README.md

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RQ (_Redis Queue_) is a lightweight<sup>*</sup> 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.
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<p style="font-size: 80%; text-align: right; font-style: italic">
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<sup>*</sup> It is under 20 kB in size and just over 500 lines of code.</p>
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## Getting started
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First, run a Redis server, of course:
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$ redis-server
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To put jobs on queues, you don't have to do anything special, just define
your typically lengthy or blocking function:
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import urllib2
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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
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Then, create a RQ queue:
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import rq import *
use_redis()
q = Queue()
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And enqueue the function call:
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from my_module import count_words_at_url
result = q.enqueue(count_words_at_url, 'http://nvie.com')
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For a more complete example, refer to the [docs][d]. But this is the essence.
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[d]: {{site.baseurl}}docs/
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### The worker
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To start executing enqueued function calls in the background, start a worker
from your project's directory:
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$ rqworker
*** Listening for work on default
Got count_words_at_url('http://nvie.com') from default
Job result = 818
*** Listening for work on default
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That's about it.
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## Installation
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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:
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pip install -e git+git@github.com:nvie/rq.git@master#egg=rq
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## Project history
This project has been inspired by the good parts of [Celery][1], [Resque][2]
and [this snippet][3], and has been created as a lightweight alternative to the
heaviness of Celery or other AMQP-based queueing implementations.
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[m]: http://pypi.python.org/pypi/mailer
[p]: http://docs.python.org/library/pickle.html
[1]: http://www.celeryproject.org/
[2]: https://github.com/defunkt/resque
[3]: http://flask.pocoo.org/snippets/73/