long_poller.rb

class LongPoller
  def self.go(&block)
    self.new(block)
  end
  def initialize(block)
    @block = block
  end
  def each(&sender)
    EM.defer do
      sender.call @block.call
    end
  end
end

projects_controller.rb

````ruby
class ProjectsController < ApplicationController
  def create
    self.status = 200
    self.content_type = 'application/json; charset=utf-8'
    self.response_body = LongPoller.go do
      # Can take up to 80 seconds
      Project.new(params[:project]).to_json
    end
  end
end