Django Varnish

Varnish is a state-of-the-art, high-performance HTTP accelerator. For more information checkout Varnish Site

Django Varnish works with Varnish server(s) to manage caching of object pages. It allows you to monitor certain models and when they are updated, Django Varnish will purge the model's absolute_url on your frontend(s). This ensures that object detail pages are served blazingly fast and are always up to date. You may also go in and manually tweak things (such as your VCL configuration) using a management command.

Setup

1. Install the varnish python bindings
2. Put varnishapp in your INSTALLED_APPS then set a few more settings.
3. Add (r'^admin/varnish/', include('varnishapp.urls')), to your URLconf

Configuration

The following settings can be configured in a VARNISH_SETTINGS setting as items of a dictionary:

• WATCHED_MODELS

  A list of installed models whose absolute_urls you want to purge from your Varnish cache upon saving. Defaults to [].

  Example: ['auth.user','profiles.profile']

• MANAGEMENT_ADDRS

  A list of Varnish cache addresses (containing their management ports). Defaults to [].

  Example: ['server1:6082','server2:6082']

• SECRET

  A string to be used as the shared secret that is configured on the Varnish servers. Defaults to ''

  Example: 'super-sekrit-password'

• THREADED

  A boolean to decide whether the connection to Varnish should be done in a different thread. Defaults to False.

Complete example:

VARNISH_SETTINGS = {
    'WATCHED_MODELS': ('auth.User', 'profiles.profile'),
    'MANAGEMENT_ADDRS': ('server1:6082','server2:6082'),
    'SECRET': 'super-sekrit-password',
    'THREADED': False,
}

Management

You can view the status of your Varnish cache servers by going to /admin/varnish/ and being a superuser. Here is what it looks like in production.

Run the management command varnishmgt to blindly execute arguments to all Varnish backends. Example:

$ ./manage.py varnishmgt purge_url "/"