code: func (s *Collector) Collect(c *container.Container) chan interface{} {
  	s.m.Lock()
  	defer s.m.Unlock()
  	publisher, exists := s.publishers[c]
  	if !exists {
  		publisher = pubsub.NewPublisher(100*time.Millisecond, 1024)
  		s.publishers[c] = publisher
  	}
  	return publisher.Subscribe()
  }
docs: // Collect registers the container with the collector and adds it to
  // the event loop for collection on the specified interval returning
  // a channel for the subscriber to receive on.