Deploying with Gunicorn

Starting with OpenERP 6.1, the server and web addons are WSGI compliant. In particular, support for the Gunicorn HTTP server is available. For some background information and motivation, please read http://www.openerp.com/node/1106. To install Gunicorn, please refer to Gunicorn’s website.

Summary

Configuring and starting an OpenERP server with Gunicorn is straightfoward. The different sections below give more details but the following steps are all it takes:

  1. Use a configuration file, passing it to gunicorn using the -c option.
  2. Within the same configuration file, also configure OpenERP.
  3. Run gunicorn openerp:service.wsgi_server.application -c openerp-wsgi.py.

Sample configuration file

A sample openerp-wsgi.py configuration file for WSGI servers can be found in the OpenERP server source tree. It is fairly well commented and easily customizable for your own usage. While reading the remaining of this page, it is advised you take a look at the sample openerp-wsgi.py file as it makes things easier to follow.

Configuration

Gunicorn can be configured by a configuration file and/or command-line arguments. For a list of available options, you can refer to the official Gunicorn documentation http://docs.gunicorn.org/en/latest/configure.html.

When the OpenERP server is started on its own, by using the openerp-server script, it can also be configured by a configuration file or its command-line arguments. But when it is run via Gunicorn, it is no longer the case. Instead, as the Gunicorn configuration file is a full-fledged Python file, we can import openerp in it and configure directly the server.

The principle can be summarized with this three lines (although they are spread across the whole sample openerp-wsgi.py file):

import openerp
conf = openerp.tools.config
conf['addons_path'] = '/home/openerp/addons/trunk,/home/openerp/web/trunk/addons'

The above three lines first import the openerp library (i.e. the one containing the OpenERP server implementation). The second one is really to shorten repeated usage of the same variable. The third one sets a parameter, in this case the equivalent of the --addons-path command-line option.

Running

Once a proper configuration file is available, running the OpenERP server with Gunicorn can be done with the following command:

> gunicorn openerp:service.wsgi_server.application -c openerp-wsgi.py

openerp must be importable by Python. The simplest way is to run the above command from the server source directory (i.e. the directory containing the openerp module). Alternatively, the module can be installed on your machine as a regular Python library or added to your PYTHONPATH.