Eventmachine Deferrable example

request.rb

require 'httparty'
require 'eventmachine'

class Request
  include EM::Deferrable

  @@requests = []

  attr_reader :method, :params

  def self.run
    return if @@requests.empty?
    EM.run do
      @@requests.each do |request|
        Thread.new do
          begin
            request.send_request
          rescue => e
            puts e.backtrace
            request.fail({"result" => {"message" => e}})
          ensure
            @@requests.delete(request)
          end
        end
      end

      until @@requests.empty?; end
      EM.stop
    end
  end

  def initialize(method, params, &callback)
    @method, @params = method, params

    self.callback(&callback)

    @@requests << self
  end

  def send_request
    @response = HTTParty.get(@method, @params)

    if @response["result"]["message"].nil?
      succeed(@response)
    else
      fail(@response)
    end
  end
end

whoismyrep = 'http://whoismyrepresentative.com/whoismyrep.php'
%w(91108 94026 90274 07620 10014 90210 10065 94920 10012 93108 11568 11013 92067 91302 94022 92661 11976 94024 11932 94010 11765 10003 21056 90265 10021).each do |zip|
  req = Request.new(whoismyrep, :query => { :zip => zip }) do |response|
    reps = response["result"]["rep"] 
    if reps.is_a?(Array)
      reps.each do |rep|
        print "#{zip}: #{rep["name"]} => District #{rep["district"]}, #{rep["phone"]}\n"
      end
    else
      print "#{zip}: #{reps["name"]} => District #{reps["district"]}, #{reps["phone"]}\n"
    end
  end

  req.callback do |response|
    rep = response["result"]["rep"]
    print "#{zip} is in #{(rep.is_a?(Array) ? rep.first : rep)["state"]}\n"
  end

  req.errback do |response|
    print "#{zip}: #{response["result"]["message"]}\n"
  end
end

Request.run