Engine Yard Cloud and Resque-Web

So at Hashrocket, we’ve been deploying a number of apps to Engine Yard Cloud. Some of these apps have required the use of background jobs. A library that facilitates that is called Resque. Once set up¹, it has a Sinatra web app you can use to monitor the queue’s progress. To make a long story short, it isn’t trivial to setup Resque Web on Engine Yard Cloud. This is what we did to make it work:

In your environment.rb add the following line:

Rails::Initializer.run do |config|
  #[...]
  config.middleware.use 'ResqueWeb'
end

Then create a library under RAILS_ROOT/lib/resque_web.rb with the following:

require 'sinatra/base'
class ResqueWeb < Sinatra::Base
  require 'resque/server'
  use Rack::ShowExceptions
  def call(env)
    if env["PATH_INFO"] =~ /^\/resque/
      env["PATH_INFO"].sub!(/^\/resque/, '')
      env['SCRIPT_NAME'] = '/resque'
      app = Resque::Server.new
      app.call(env)
    else
      super
    end
  end
end

That’s it. Deploy your app to staging to test it and boom!