Cannot load Rack Middleware file into Rails app

Question

Trying to get Heroku's WebSocket tutorial working with a Rails app but the middleware is not loading.

Steps to reproduce:

• Created a Rails 3.2.15 app.
• Add faye-websocket gem and run bundle install
• Create app/middleware directory in the application
• Copy over the the following into app/middleware/test_server.rb

require 'faye/websocket'

class TestServer
  KEEPALIVE_TIME = 15 # in seconds

  def initialize(app)
    @app     = app
    @clients = []
  end

  def call(env)
  end
end

• Add the following to config/application.rb

config.middleware.use TestServer

• Run rails console

I see the following error:

config/application.rb:64:in `': uninitialized constant RackMiddleware::Application::TestServer (NameError)

If I add require 'test_server', I see the following error:

config/application.rb:5:in `require': cannot load such file -- test_server (LoadError)

I thought an directories in app/ were automatically added in Rails 3. What am I doing wrong?

Answer 1

Looks like the problem is that the TestServer has to be in quotes for config.middleware.use call.

The answer here helped: https://stackoverflow.com/a/16206347/3467

The Heroku howto is incorrect, sent them an comment to fix it.