sucker_punch.rb

class EmailJob
  include SuckerPunch::Job

  def perform(user_id)
    UserMailer.welcome(user_id).deliver
  end  
end

module SuckerPunch
  module Job
    def self.included(base)
      base.send(:include, ::Celluloid)
    end

    # we want perform_with_pool_check to define the pool before calling #perform
    def perform_with_pool_check(*args, &block)
      define_celluloid_pool
      perform(*args, &block)
    end
    
    # we want perform_without_pool_check just be a pass-through to perform #perform
    # this probably could be removed if the alias for it was just a convenience
    def perform_without_pool_check(*args, &block)
      perform(*args, &block)
    end
    
    # this is what the subclass is expected to define
    # should always include this in the super class, so the subclass knows what the contract is
    def perform(*args, &block)
      raise "Implement #perform to define work needed by this job"
    end

    private

    def define_celluloid_pool
      unless SuckerPunch::Queues.registered?(queue_name)
        Celluloid::Actor[queue_name] = self.class.send(:pool)
        SuckerPunch::Queues.register(queue_name)
      end
    end

    def queue_name
      self.class.to_s.underscore.to_sym
    end
  end
end