Deployment using Gunicorn¶
aiohttp can be deployed using Gunicorn, which is based on a pre-fork worker model. Gunicorn launches your app as worker processes for handling incoming requests.
Prepare environment¶
You firstly need to setup your deployment environment. This example is based on Ubuntu 14.04.
Create a directory for your application:
>> mkdir myapp
>> cd myapp
Ubuntu has a bug in pyenv, so to create virtualenv you need to do some extra manipulation:
>> pyvenv-3.4 --without-pip venv
>> source venv/bin/activate
>> curl https://bootstrap.pypa.io/get-pip.py | python
>> deactivate
>> source venv/bin/activate
Now that the virtual environment is ready, we’ll proceed to install aiohttp and gunicorn:
>> pip install gunicorn
>> pip install -e git+https://github.com/KeepSafe/aiohttp.git#egg=aiohttp
Application¶
Lets write a simple application, which we will save to file. We’ll name this file my_app_module.py:
from aiohttp import web
def index(request):
return web.Response(text="Welcome home!")
my_web_app = web.Application()
my_web_app.router.add_route('GET', '/', index)
Start Gunicorn¶
When Running Gunicorn, you provide the name of the module, i.e. my_app_module, and the name of the app, i.e. my_web_app, along with other Gunicorn Settings provided as command line flags or in your config file.
In this case, we will use:
- the ‘–bind’ flag to set the server’s socket address;
- the ‘–worker-class’ flag to tell Gunicorn that we want to use a custom worker subclass instead of one of the Gunicorn default worker types;
- you may also want to use the ‘–workers’ flag to tell Gunicorn how many worker processes to use for handling requests. (See the documentation for recommendations on How Many Workers?)
The custom worker subclass is defined in aiohttp.worker.GunicornWebWorker and should be used instead of the gaiohttp worker provided by Gunicorn, which supports only aiohttp.wsgi applications:
>> gunicorn my_app_module:my_web_app --bind localhost:8080 --worker-class aiohttp.worker.GunicornWebWorker
[2015-03-11 18:27:21 +0000] [1249] [INFO] Starting gunicorn 19.3.0
[2015-03-11 18:27:21 +0000] [1249] [INFO] Listening at: http://127.0.0.1:8080 (1249)
[2015-03-11 18:27:21 +0000] [1249] [INFO] Using worker: aiohttp.worker.GunicornWebWorker
[2015-03-11 18:27:21 +0000] [1253] [INFO] Booting worker with pid: 1253
Gunicorn is now running and ready to serve requests to your app’s worker processes.
More information¶
The Gunicorn documentation recommends deploying Gunicorn behind a Nginx proxy server. See the official documentation for more information about suggested nginx configuration.
