ember-rails

ember-rails allows you to include Ember.JS into your Rails 3.1+ application.

The gem will also pre-compile your handlebars templates when building your asset pipeline. It includes development and production copies of Ember.

You can see an example of how to use the gem here. There is also a great tutorial by Dan Gebhardt called "Beginning Ember.js on Rails" which is a great read if you're just starting out with Rails and Ember.js

Getting started

Add the gem to your application Gemfile:

gem "ember-rails"

Run bundle install and add the following line to app/assets/javascripts/application.js:

//= require ember

Ember-rails will use the production build of Ember.js when Rails is running in production mode, and the development build otherwise.

Architecture

Ember does not require an organized file structure. However, ember-rails allows you to use rails g ember:bootstrap to create the following directory structure under app/assets/javascripts:

controllers/
helpers/
models/
routes/
templates/
views/

Additionally, it will add the following lines to app/assets/javascripts/application.js. By default, it uses the Rails Application's name and creates an rails_app_name.js file to setup application namespace and initial requires:

//= require ember
//= require ember/app

Example:

rails g ember:bootstrap
  insert  app/assets/javascripts/application.js
  create  app/assets/javascripts/models
  create  app/assets/javascripts/models/.gitkeep
  create  app/assets/javascripts/controllers
  create  app/assets/javascripts/controllers/.gitkeep
  create  app/assets/javascripts/views
  create  app/assets/javascripts/views/.gitkeep
  create  app/assets/javascripts/helpers
  create  app/assets/javascripts/helpers/.gitkeep
  create  app/assets/javascripts/templates
  create  app/assets/javascripts/templates/.gitkeep
  create  app/assets/javascripts/app.js

If you want to avoid .gitkeep files, use the skip git option like this: rails g ember:bootstrap -g.

Ask Rails to serve HandlebarsJS and pre-compile templates to Ember by putting each template in a dedicated ".js.hjs", ".hbs" or ".handlebars" file (e.g. app/assets/javascripts/templates/admin_panel.handlebars) and including the assets in your layout:

<%= javascript_include_tag "templates/admin_panel" %>

If you want to strip template root from template names, add templates_root option to your application configuration block :

config.handlebars.templates_root = 'templates'

The result will be like this :

Ember.TEMPLATES['admin_panel'] = "...";

If you want a different path separator in template names add templates_path_separator option to your application configuration block :

config.handlebars.templates_path_separator = '-'

The result will be like this :

Ember.TEMPLATES['templates-admin_panel'] = "...";

Default behavior for ember-rails is to precompile handlebars templates only in production environment. If you don't want this behavior you can turn it off in your application configuration block :

config.handlebars.precompile = false

(Remember to clear the local sprockets cache if you change the value of precompile, by default at tmp/cache/assets)

Bundle all templates together thanks to Sprockets, e.g create app/assets/javascripts/templates/all.js with:

//= require_tree .

Now a single line in the layout loads everything:

<%= javascript_include_tag "templates/all" %>

If you use Slim or Haml templates, you can use handlebars filter :

handlebars:
    {{#view Ember.Button}}OK{{/view}}

It will be translated as :

<script type="text/x-handlebars">
    {{#view Ember.Button}}OK{{/view}}
</script>

Note on Patches/Pull Requests

Fork the project.
Make your feature addition or bug fix.
Add tests for it. This is important so I don't break it in a future version unintentionally.
Commit, do not mess with rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
Send me a pull request. Bonus points for topic branches.