work fiber

fiber.rb

def example
  # original code
  def work(item)
    check?(item)
    result = http_post("server/calculate", item.id)
    item.update_attributes(result: result)
  end
  items.map{|item| work(item)}

  # support async now
  def work(item, opt={})
    check?(item)
    if opt[:async]
      request = async_http_post("server/calculate", item.id)
      Fiber.yield
      while true
        next unless request.done?
        result = request.result
      end
    else
      result = http_post("server/calculate", item.id)
    end
    item.update_attributes(result: result)
  end

  # run method
  fibers = (1..3).map do |i|
    Fiber.new do
      Fiber.yield
      while items.present?
        item = items.pop
        work(item, async: true)
      end
    end
  end
  while not items.empty?
    fibers.sample.resume
  end
  
end