Django Media Bundler

Django Media Bundler is a Django plugin bundles up your Javascript, CSS, and icons for production, while still being easy to debug during development. To use the media bundler, you just have to describe the media you would like to be bundled together in your settings.py file, and run python manage.py bundle_media. The Media Bundler is inspired by the Rails' Asset Packager plugin, which helps do roughly the same things for Rails. This is not the first Django application for this task, and it is probably not the last. You can find a good comparison of other media bundling tools here.

Supported Bundle Types

• Javascript: The media bundler will concatenate and optionally minify your Javascript. It also lets you to defer loading Javascript until the end of the document, as described in here. We do not support packing, because that has been shown to slow down Javascript execution.
• CSS: The media bundler will concatenate and optionally minify CSS. It does not defer CSS, because that makes the page appear to load more slowly.
• Image Sprites: The media bundler will take a list of your icons and arrange them into a new and compact PNG image sprite. It will then run pngcrush on the resulting image, and generate CSS class names and rules to display your icons.

Dependencies

• Python 2.5+

For image sprites:

• Python Imaging Library (spelled python-imaging under Ubuntu)
• pngcrush

Installation

The media-bundler is a reusable app, so to install it all you have to do is clone the source tree, put it somewhere in Django's PYTHONPATH, and add it to INSTALLED_APPS in settings.py.

Usage

Describe the Javascript and CSS bundles you would like to create in settings.py roughly like so:

MEDIA_BUNDLES = (
    {"type": "javascript",
     "name": "myapp_scripts",
     "path": MEDIA_ROOT + "/scripts/",
     "url": MEDIA_URL + "/scripts/",
     "minify": True,  # If you want to minify your source.
     "files": (
         "foo.js",
         "bar.js",
         "baz.js",
     )},
    {"type": "css",
     "name": "myapp_styles",
     "path": MEDIA_ROOT + "/styles/",
     "url": MEDIA_URL + "/styles/",
     "minify": True,  # If you want to minify your source.
     "files": (
         "foo.css",
         "bar.css",
         "baz.css",
         "myapp-sprites.css"  # Include this generated CSS file.
     )},
    {"type": "png-sprite",
     "name": "myapp_sprites",
     "path": MEDIA_ROOT + "/images/",
     "url": MEDIA_URL + "/images/",
     # Where the generated CSS rules go.
     "css_file": MEDIA_ROOT + "/styles/myapp-sprites.css",
     "files": (
         "foo.png",
         "bar.png",
         "baz.png",
     )},
)

By default, deferring is enabled, and bundling is disabled when settings.DEBUG is True. You can override those values in your settings module by adding the line:

FORCE_BUNDLES = True

See the media_bundle.default_settings module for more info.

To source your Javascript and CSS, put {% load bundler_tags %} at the top of your template, and wherever you used to write this:

<script type="text/javascript" src="/url/myscript.js"></script>
<link rel="stylesheet" type="text/css" href="/url/mystyle.css"/>

you should write this:

{% javascript "js_bundle_name" "myscript.js" %}
{% css "css_bundle_name" "mystyle.css" %}

If you want, you can load all the files in a bundle at once with the load_bundle tag:

{% load_bundle "js_bundle_name" %}
{% load_bundle "css_bundle_name" %}

load_bundle will add {% css %} and {% javascript %} tags for all the files in the bundle.

If you are deferring your Javascript, then at the bottom of your base template you should insert the tag {% deferred_content %}. We recommend opening a second head tag after your body and putting it there.

Once your settings file is configured, you'll need to run the following line to generate the concatenated (and minimised) files:

python manage.py bundle_media