code: func (s *Server) Stop() {
  	if atomic.CompareAndSwapInt32(&s.run, 1, 0) {
  		log.Debug("RPC server shutting down")
  		s.codecs.Each(func(c interface{}) bool {
  			c.(ServerCodec).Close()
  			return true
  		})
  	}
  }
docs: // Stop stops reading new requests, waits for stopPendingRequestTimeout to allow pending
  // requests to finish, then closes all codecs which will cancel pending requests and
  // subscriptions.