compass_initializer.rb

# Set up rendering of sass through ERB in ActionView
require 'ersass_template_handler'
ActionView::Template.register_template_handler :sass, ActionView::TemplateHandlers::ErSass
ActionView::Template.exempt_from_layout :sass

ersass_template_handler.rb

## Preprocess SASS templates through ERB
module ActionView
  module TemplateHandlers
    class ErSass < TemplateHandler
      include Compilable

      def initialize(view=nil)
        @view = view
      end

      def compile(template)
        <<-END.gsub("\n", ";")
        controller.headers['Content-Type'] = 'text/css'
        controller.headers['Cache-Control'] = 'max-age=86400 public'
        __in_erb_template = true
        erbout = eval(ERB.new(template.source).src)
        @output_buffer = Sass::Engine.new(erbout, Sass::Plugin.engine_options).render
        END
      end
    end
  end
end