deployment.txt

.. _ref-deployment:

Deployment
==========

In short: 

* Create a ``local_settings.py`` alongside ``settings.py`` for your
  host-specific settings (like database connection, email, etc).
* Configure mod_wsgi or mod_python.
* Set up ``cron`` job for mailer and asynchronous notifications.

Using mod_wsgi
--------------

If you are using mod_wsgi, which we recommend, you will need to provide a WSGI
script. All projects include a ``deploy/`` directory which contains this
script named ``pinax.wsgi``. You may modify this file as it best suits you.

Here is a basic configuration for Apache (assuming you are using Python 2.5)::

    WSGIDaemonProcess mysite-production python-path=/path/to/virtualenvs/pinax-env/lib/python2.5/site-packages
    WSGIProcessGroup mysite-production
    
    WSGIScriptAlias / /path/to/project/deploy/pinax.wsgi
    <Directory /path/to/project/deploy>
        Order deny,allow
        Allow from all
    </Directory>

The above configuration will likely need to be modified before use. Most
specifically make sure the ``python-path`` option points to the right Python
version. We encourage you to read about `WSGIDaemonProcess`_ to learn more
about what you can configure.

Using mod_python
----------------

While we highly recommend you use mod_wsgi you may need to use mod_python. In
this case we have provided the correct hooks for you to use Pinax. Here is a
sample Apache config that you can use::

    <Location "/">
        SetHandler python-program
        PythonHandler social_project.deploy.modpython
        SetEnv DJANGO_SETTINGS_MODULE social_project.settings
        PythonDebug On
        PythonPath "['/path/to/pinax/projects'] + sys.path"
    </Location>

.. note::

    It is important to note that you should pay careful attention to the
    value of ``PythonHandler`` above. It is *not* using
    ``django.core.handlers.modpython``. It is using a mod_python handler
    located in your project's ``deploy/`` directory. The reason why we have
    our own mod_python handler is because we need to setup the Pinax
    environment otherwise you will see failing imports.

.. _ref-sending-mail-and-notices:

Sending Mail and Notices
------------------------

Both mail messages and (some) notifications are queued for asynchronous
delivery. To actually deliver them you need to run::
    
    python manage.py send_mail
    
and::
    
    python manage.py emit_notices
    
on a frequent, regular basis.

Because failed mail will be deferred, you need an additional, less
frequent, run of::
    
    python manage.py retry_deferred
    
We recommend setting up some scripts to run these commands within your
virtual environment. You can use the following shell script as the basis for
each management command::

    #!/bin/sh

    WORKON_HOME=/home/user/virtualenvs
    PROJECT_ROOT=/path/to/project

    # activate virtual environment
    . $WORKON_HOME/pinax-env/bin/activate

    cd $PROJECT_ROOT
    python manage.py send_mail >> $PROJECT_ROOT/logs/cron_mail.log 2>&1

Let's assume the scripts you create from above are stored in
``$PROJECT_ROOT/cron``. You can now setup the cron job similar to::
    
    * * * * * /path/to/project/cron/send_mail.sh
    * * * * * /path/to/project/cron/emit_notices.sh
    
    0,20,40 * * * * /path/to/project/cron/retry_deferred.sh

This runs ``send_mail`` and ``emit_notices`` every minute and
``retry_deferred`` every 20 minutes.

Media files
-----------

Pinax makes it very easy to combine all your applications' media files into
one single location (see :ref:`ref-media` for details). Serving them more or
less comes down again to how you do it with Django itself.

There is an example on how to serve those files with the development server in
:ref:`ref-media-devel`.

In a production environment you, too, have to merge those files before you can
serve them. Regarding actually serving those files then, see `Django's
deployment documentation`_ for details.

.. _`WSGIDaemonProcess`: http://code.google.com/p/modwsgi/wiki/ConfigurationDirectives#WSGIDaemonProcess
.. _django's deployment documentation: http://docs.djangoproject.com/en/dev/howto/deployment/