Method MultipleRequest

messagebus/nats.go:186–222

MultipleRequest sends a request message to multiple consumers

(topic string, req *proxy.Request, expectedResp int)

// MultipleRequest sends a request message to multiple consumers
func (n *NatsBus) MultipleRequest(topic string, req *proxy.Request, expectedResp int) ([]*proxy.Response, error) {
	var responses []*proxy.Response

	reply := rid.New("rp")

	rf := &responseForwarder{
		expected: expectedResp,
		fwdChan:  make(chan *proxy.Response),
	}

	replySub, err := n.conn.Subscribe(reply, rf.Forward)
	if err != nil {
		return nil, eris.Wrap(err, "failed to subscribe to data responses")
	}
	defer replySub.Unsubscribe() // nolint: errcheck

	// Make an all-call for the entity data
	err = n.conn.PublishRequest(topic, reply, req)
	if err != nil {
		return nil, eris.Wrap(err, "failed to make request for data")
	}

	// Wait for replies
	timer := time.NewTimer(n.Config.RequestTimeout)
	defer timer.Stop()
	for {
		select {
		case <-timer.C:
			return responses, nil
		case resp, more := <-rf.fwdChan:
			if !more {
				return responses, nil
			}
			responses = append(responses, resp)
		}
	}
}

// MultipleRequestReturnFirstGoodResponse sends a request message to multiple consumers and returns the first good response
func (n *NatsBus) MultipleRequestReturnFirstGoodResponse(topic string, req *proxy.Request, expectedResp int) (*proxy.Response, error) {