[ Ruby / Bunny / RabbitMQ ]: Lightweight Resque interface made via MessageQueue

message_queue.rb

require 'bunny'
require 'json'
require 'pry'

class MessageQueue
  attr_reader :channel, :service, :queue

  def initialize(service, channel)
    @channel = channel
    @service = service
    @queue   = service.create_channel.queue(channel, durable: true)
  end

  def enqueue(klass, *args)
    pub(class: klass, args: args)
  end

  def work(channel_name = channel)
    service.with_channel do |service_channel|
      ServiceWorker.new(channel_name, service_channel).perform
    end
  end

  private

  def pub(message)
    queue.publish(message.to_json,
      content_type: 'application/json',
      persistent:   true
    )
  end

  class ServiceWorker
    attr_reader :channel_name, :local_queue, :service_channel

    def initialize(channel_name, service_channel)
      @channel_name    = channel_name
      @service_channel = service_channel
      @local_queue     = service_channel.queue channel_name, durable: true
    end

    def perform
      local_queue.subscribe(ack: true, block: true) do |delivery, _, payload|
        begin
          payload = JSON.parse payload, symbolize_names: true
          job     = Kernel.const_get(payload.fetch(:class))

          job.perform(*payload.fetch(:args))
          service_channel.acknowledge(delivery.delivery_tag, false)
        rescue Exception => e
          service_channel.reject(delivery.delivery_tag, false)
        end
      end
    end

  end

end

class Derper
  def self.perform(*derpies)
    derpies.each { |derp| puts derp.inspect }
  end
end

BUNNY = Bunny.new 'amqp://guest:guest@localhost'
BUNNY.start

MESSAGES = MessageQueue.new BUNNY, "application_name"

def do_the_derp(derps = 10)
  MESSAGES.enqueue Derper, *["Derp"]*derps
end

do_the_derp

MESSAGES.work