Sinatra Heroku and config.ru

Rack applications often require a config.ru for deployment. The standard config.ru for classic sinatra applications is well documented:

require 'app'
run Sinatra::Application

The requirments for classy apps is not very well documented, currently I use this on heroku:

#For Ruby 1.8.7 (the 1.9.2 version should also work) on Heroku
require 'app'
run MyModule::MyApp

After trying Ruby 1.9.2 I had to add ./ to my app require. The current directory has been removed from the load path adding ./ removes the problem because it explicitly defines the path.

#For Ruby 1.9.2 on Heroku
require './app'
run MyModule::MyApp

For a sinatra Application which may look like:

require 'sinatra/base'
module MyModule
  class MyApp < Sinatra::Base
    get '/' do
      'HelloWorld!'
    end
  end
end

#if file called directly launch app (ie ruby my_app.rb)
if $0 == __FILE__
  MyModule::MyApp.run!
end