Assets Packager

A bundler for your javascripts and stylesheets.

When you deploy your application it could be convenient to package all your stylesheets and javascripts in a single file, let say all.css and all.js, in order to decrease the HTTP requests against your server.

You may also find useful to reduce the size of those files, through a process which eliminates all unneeded white spaces and comments.

Assets Packager helps you to solve these problems.

Installation

# Gemfile
gem 'assets_packager'

# lib/tasks/assets.rake
require 'assets_packager/tasks'

# shell
$ rake assets:install

If you are in a Rails context, you don't need to setup anything else, otherwise you can specify your paths:

AssetsPackager.configure do |config|
  config.root_path = '/path/to/public/folder'
  config.file_path = '/path/to/assets.yml'
end

Assets configuration

Once you use new assets to your application, just add the to the configuration file (look at config/assets.yml):

---
css:
- application
- jquery-ui
js:
- jquery
- jquery-ui
- application

Make sure to include library first, you may want to add jquery.js before of application.js.

Usage

Assets Packager has a lot of useful Rake tasks (rake -T assets), the most important is assets:package: it merge and compress all your javascripts and stylesheets. Use it as Capistrano post deploy hook.

If you're using Rails, in order to take advantage of bundled assets, you should use :cache => true option:

<%= javascript_include_tag 'jquery', 'jquery-ui', 'application', :cache => true %>
<%= stylesheet_link_tag 'application', 'jquery-ui', :cache => true %>

There are some contexts where you can't bundle assets at deploy time (like Heroku), what you can do is to reference directly to all.js or all.css:

<%= javascript_include_tag 'all' %>
<%= stylesheet_link_tag 'all' %>

In this way you have to bundle assets on your development machine and put them under version control.

Credits

Assets Packager was strongly inspired by the homonym plugin written by Scott Becker.

Uladzislau Latynski for his jsmin.rb Ruby porting.

Thanks to Steve Souders for his High Performance Web Sites book.