Serving ember templates from rails

handlebars.rb

# Put in config/initializers/handlebars.rb
# Add templates to app/assets/javascripts/templates/whatever.js.handlebars
# Then require from applicaiton.js (or any manifest) as usual. e.g.
# //= require_tree templates

class EmberHandlebars < Tilt::Template
  def self.default_mime_type
    'application/javascript'
  end

  def prepare; end

  def evaluate scope, locals, &block
    path = scope.logical_path.gsub /^templates\//, ''
    <<-JS
      window.Ember.TEMPLATES["#{path}"] = Ember.Handlebars.compile(#{MultiJson.dump data});
    JS
  end
end

Sprockets.register_engine '.handlebars', EmberHandlebars