gocw2/mq.go

package main

import (
	"encoding/json"
	"log"
	"strconv"

	"github.com/streadway/amqp"
)

func MQSendMsgWorker(id int, msgs <-chan ChatWarsMessage) {
	conn, err := amqp.Dial("amqp://" + cfg.Rabbit.User + ":" + cfg.Rabbit.Password + "@" + cfg.Rabbit.Host + "/" + cfg.Rabbit.SendQueue)
	failOnError(err, "MQSendMsgWorker["+strconv.Itoa(id)+"] : Failed to connect to RabbitMQ")
	defer conn.Close()

	ch, err := conn.Channel()
	failOnError(err, "MQSendMsgWorker["+strconv.Itoa(id)+"] : Failed to open a channel")
	defer ch.Close()

	q, err := ch.QueueDeclare(
		"msg", // name
		false, // durable
		false, // delete when unused
		false, // exclusive
		false, // no-wait
		nil,   // arguments
	)
	failOnError(err, "MQSendMsgWorker["+strconv.Itoa(id)+"] : Failed to declare a queue")

	for m := range msgs {
		b, err := json.Marshal(m)
		if err != nil {
			logOnError(err, "MQSendMsgWorker["+strconv.Itoa(id)+"] : Marshaling message.")
		} else {
			err = ch.Publish(
				"",     // exchange
				q.Name, // routing key
				false,  // mandatory
				false,  // immediate
				amqp.Publishing{
					ContentType: "application/json",
					Body:        []byte(b),
				})
			if err != nil {
				logOnError(err, "MQSendMsgWorker["+strconv.Itoa(id)+"] : Publishing message.")
			}
		}
	}

	log.Printf("MQSendMsgWorker[" + strconv.Itoa(id) + "] : Closing.")

}

func MQReceiveMsgWorker(id int, cmd chan<- ChatWarsCommand) {
	conn, err := amqp.Dial("amqp://" + cfg.Rabbit.User + ":" + cfg.Rabbit.Password + "@" + cfg.Rabbit.Host + "/" + cfg.Rabbit.ReceiveQueue)
	failOnError(err, "MQReceiveMsgWorker["+strconv.Itoa(id)+"] : Failed to connect to RabbitMQ")
	defer conn.Close()

	ch, err := conn.Channel()
	failOnError(err, "MQReceiveMsgWorker["+strconv.Itoa(id)+"] : Failed to open a channel")
	defer ch.Close()

	q, err := ch.QueueDeclare(
		"msg", // name
		false, // durable
		false, // delete when unused
		false, // exclusive
		false, // no-wait
		nil,   // arguments
	)
	failOnError(err, "MQReceiveMsgWorker["+strconv.Itoa(id)+"] : Failed to declare a queue")

	m, err := ch.Consume(
		q.Name, // queue
		"",     // consumer
		true,   // auto-ack
		false,  // exclusive
		false,  // no-local
		false,  // no-wait
		nil,    // args
	)
	failOnError(err, "MQReceiveMsgWorker["+strconv.Itoa(id)+"] : Failed to declare a consumer")

	for d := range m {
		// log.Printf("MQReceiveMsgWorker["+strconv.Itoa(id)+"] : Received a message: %s", string(d.Body))
		err = json.Unmarshal(d.Body, &x)
		logOnError(err, "MQReceiveMsgWorker["+strconv.Itoa(id)+"] : Can't unmarshal.\n"+string(d.Body))
		if err == nil {
			cmd <- x
		}
	}

	log.Printf("MQReceiveMsgWorker[" + strconv.Itoa(id) + "] : Closing.")

}