nano_worker

nano_worker.rb

# NanoWorker
# nano worker implementation use by thread
class NanoWorker
  attr_accessor :queue, :thread

  @@thread_map = {}

  class << self
    def [](name)
      @@thread_map[name] ||= new
    end

    def each
      @@thread_map.each { |m| yield m }
    end
  end

  def initialize
    @queue = Queue.new
    @thread = nil
    @after_perform = Proc.new{}
  end

  # set job
  # NanoWorker['some_thread_name'].perform(some_obj) do |some_obj_local|
  #   some_obj_local.some_method
  # end
  def perform(*args)
    @thread ||= Thread.new {
      loop do
        a = @queue.pop
        yield *a
        @after_perform.call(self, *a)
      end
    }
    @queue.push args
  end

  # wait and kill when finish all task
  def join
    if 0 < @queue.size
      after_perform do |m, *other|
        m.kill if m.queue.size == 0
      end
      @thread.join
    end
  end

  # you can set callback called when after perform
  # NanoWorker['some_thread_name'].after_perform do |some_obj_local|
  #   p some_obj_local
  # end
  def after_perform(&block)
    @after_perform = block
  end

  def kill
    @thread.kill
    @queue.clear
  end
end