Integrates RequireJS into the Rails 3+ Asset Pipeline.
UPGRADE NOTES: Users upgrading within the 0.x series should read the Changes section for relevant usage changes. We're pushing hard to 1.0, when the configuration and setup details will be declared stable. Until that time expect some bumps as things bake out.
Add this to your Rails app's Gemfile:
gem 'requirejs-rails'Remove all Sprockets directives such as //= require jquery from application.js and elsewhere. Instead establish JavaScript dependencies using AMD-style define() and require() calls.
Use requirejs_include_tag at the top-level of your app's layout(s). Other modules will be pulled in dynamically by require.js in development and for production builds optimized by r.js. Here's a basic app/views/layouts/application.html.erb modified for requirejs-rails:
<!DOCTYPE html>
<html>
<head>
<title>Frobnitz Online</title>
<%= stylesheet_link_tag "application" %>
<%= requirejs_include_tag "application" %>
<%= csrf_meta_tags %>
<meta charset="utf-8">
</head>
<body>
<%= yield %>
</body>
</html>Organize your JavaScript or CoffeeScript code into modules using define():
# app/assets/javascripts/views/tweet_view.js.coffee
define ['backbone'], (Backbone) ->
class TweetView extends Backbone.View
# ...Instantiate your app using require() from a top-level module such as application.js:
# app/assets/javascripts/application.js.coffee
require ['jquery', 'backbone', 'TheApp'], ($, Backbone, TheApp) ->
# Start up the app once the DOM is ready
$ ->
window.App = new TheApp()
Backbone.history.start
pushState: true
window.App.start()When ready, build your assets for production deployment as usual.
requirejs-rails defaults to a single-file build of application.js.
Additional modules and r.js layered builds may be specified via
config/requirejs.yml; see the Configuration section below.
rake assets:precompile
Configuration lives in config/requirejs.yml. These values are inspected and
used by requirejs-rails and passed along as configuration for require.js and
r.js. The default configuration declares application.js as the sole
top-level module. This can be overridden by creating
a config/requirejs.yml, such as:
modules:
- name: 'mytoplevel'You may pass in require.js config options as needed. For example, to add path parameters:
paths:
d3: "d3/d3"
"d3.time": "d3/d3.time"Only modules specified in the configuration will be created as build artifacts
by r.js. Layered r.js
builds be
configured like so:
modules:
- name: 'appcommon'
- name: 'page1'
exclude: ['appcommon']
- name: 'page2'
exclude: ['appcommon']
priority: ['appcommon']In this example, only modules page1 and page2 are intended for direct
loading via requirejs_include_tag. The appcommon module contains
dependencies shared by the per-page modules. As a guideline, each module in
the configuration should be referenced by one of:
requirejs_include_tag in a templaterequire() call. Modules which are solely
referenced by a dynamic require() call (i.e. a call not optimized by r.js)
must be specified in the modules section in order to produce a correct
build.appcommon, listed in the priority config
option.This gem supports single-file builds with
almond. Use the following setting in
application.rb to enable it:
config.requirejs.loader = :almondAlmond builds have the restriction that there must be exactly one modules entry in
requirejs.yml. Typically the wrap option will be used to create a self-contained build:
modules:
- name: 'main'
wrap: trueThe requirejs-rails build process uses the Asset Pipeline to assemble assets
for the r.js build. By default, assets ending in .js, .html, and .txt
will be made available to the build. If you have other asset suffixes to
include, use the logical_path_patterns config setting to add them.
For example, if your templates all end in .templ like so...
// in app/assets/javascripts/myapp.js
define(function (require) {
var stuff = require('text!stuff.templ');
// ...
});... then this config setting will ensure they're picked up in the build:
# in config/application.rb
config.requirejs.logical_path_patterns += [/\.templ$/]requirejs_include_tag accepts an optional block which should return a hash.
This hash will be used to populate additional data-... attributes like so:
<%= requirejs_include_tag "page1" do |controller|
{ 'foo' => controller.foo,
'bar' => controller.bar
}
end
%>This will generate a script tag like so:
<script data-main="/assets/page1.js" data-foo="..." data-bar="..." src="https://github.com/jwhitley/requirejs-rails/raw/master/assets/require.js"></script>There are two ways in which requirejs-rails supports the use of different domains for serving built JavaScript modules, as is the case when using a CDN.
URLs in paths config in requirejs.yml:
If requirejs-rails encounters an URL as the right-hand side of a paths
configuration, it will correctly emit that as "empty:" during the build
process so that r.js will do the right thing.
Example:
paths:
jquery: "https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"Deploying all requirejs-rails assets to a CDN:
In config/environments/production.rb (or another environment)
set the run_config as follows:
config.requirejs.run_config['baseUrl'] = 'http://mycdn.example.com/12345abc/assets'The asset_sync gem is one
tool that can be used to deploy your built assets to a CDN (S3, in this
case).
config.assets.precompileDon't set config.assets.precompile to reference any of your AMD module code.
Avoid it altogether, except to reference non-AMD code that you're loading via
javascript_include_tag, and which is never referenced by the AMD codebase.
I currently recommend placing your AMD libraries into
vendor/assets/javascripts. The needs of a few specific libraries are
discussed below.
jQuery users must use jQuery 1.7 or later (jquery-rails >= 1.0.17) to use it as an AMD module with RequireJS. To use jQuery in a module:
# app/assets/javascripts/hello.js
define ['jquery'], ($) ->
(id) ->
$(id).append('<div>hello!</div>')Backbone 0.9.x doesn't support AMD natively. I recommend the amdjs fork of Backbone which adds AMD support and actively tracks mainline.
Underscore 1.3.x likewise doesn't have AMD support. Again, see the amdjs fork of Underscore.
Usage changes that may break functionality for those upgrading along the 0.x series are documented here. See the Changelog for the full list of feature additions, bugfixes, etc.
requirejs_include_tag now generates a data-main attribute if given an argument, ala:
<%= requirejs_include_tag "application" %>This usage is preferred to using a separate
javascript_include_tag, which will produce errors from require.js or
r.js if the included script uses define anonymously, or not at all.
application.js is configured as the default top-level module for r.js builds.baseUrl explicitly in the configuration.application.js (ala require.config(...)) to config/requirejs.ymlPlease check out our GitHub issues page to see what's upcoming and to file feature requests and bug reports.
Copyright 2011-2014 John Whitley. See the file MIT-LICENSE for terms.