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---
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title: "RQ: Using RQ on Heroku"
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layout: patterns
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---
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## Using RQ on Heroku
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To setup RQ on [Heroku][1], first add it to your
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`requirements.txt` file:
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redis>=3
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rq>=0.13
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Create a file called `run-worker.py` with the following content (assuming you
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are using [Redis To Go][2] with Heroku):
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{% highlight python %}
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import os
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import urlparse
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from redis import Redis
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from rq import Queue, Connection
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from rq.worker import HerokuWorker as Worker
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listen = ['high', 'default', 'low']
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redis_url = os.getenv('REDISTOGO_URL')
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if not redis_url:
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raise RuntimeError('Set up Redis To Go first.')
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urlparse.uses_netloc.append('redis')
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url = urlparse.urlparse(redis_url)
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conn = Redis(host=url.hostname, port=url.port, db=0, password=url.password)
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if __name__ == '__main__':
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with Connection(conn):
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worker = Worker(map(Queue, listen))
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worker.work()
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{% endhighlight %}
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Then, add the command to your `Procfile`:
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worker: python -u run-worker.py
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Now, all you have to do is spin up a worker:
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{% highlight console %}
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$ heroku scale worker=1
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{% endhighlight %}
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## Putting RQ under foreman
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[Foreman][3] is probably the process manager you use when you host your app on
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Heroku, or just because it's a pretty friendly tool to use in development.
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When using RQ under `foreman`, you may experience that the workers are a bit
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quiet sometimes. This is because of Python buffering the output, so `foreman`
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cannot (yet) echo it. Here's a related [Wiki page][4].
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Just change the way you run your worker process, by adding the `-u` option (to
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force stdin, stdout and stderr to be totally unbuffered):
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worker: python -u run-worker.py
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[1]: https://heroku.com
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[2]: https://devcenter.heroku.com/articles/redistogo
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[3]: https://github.com/ddollar/foreman
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[4]: https://github.com/ddollar/foreman/wiki/Missing-Output
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