Example #1
0
/**
 * Initializes the connection, channel and queues for the struct
 */
func (mq *AMQP) Init(address string) *AMQP {

	// Holder var for errors
	var err error

	// Create connection
	mq.Connection, err = amqp.Dial(address)
	util.FailOnError(err, "Failed to connect to RabbitMQ address: "+address)

	// Create Channel
	mq.Channel, err = mq.Connection.Channel()
	util.FailOnError(err, "Failed to open RabbitMQ channel")

	// Set quality into channel (not sure if it even works ...)
	err = mq.Channel.Qos(
		1,     // prefetch count
		0,     // prefetch size
		false, // global
	)
	util.FailOnError(err, "Failed to set QoS on channel")

	// Init queues map
	mq.Queues = make(map[string]*amqp.Queue)

	return mq
}
Example #2
0
/**
 * Sends a message to a exchange channel with route
 */
func (mq *AMQP) SendMessage(inMsg models.QueueMessage) *AMQP {

	// Encode message
	msg, err := json.Marshal(inMsg)
	if err != nil {
		fmt.Println(err.Error())
		return mq
	}

	// Parse exchange from original sender
	exchange := strings.Split(inMsg.Receiver, ".")[0]

	// Try to publish message to relevant exchange channel with proper routing
	err = mq.Channel.Publish(
		exchange,       // exchange
		inMsg.Receiver, // routing key
		false,          // mandatory
		false,          // immediate
		amqp.Publishing{
			DeliveryMode: amqp.Persistent,
			ContentType:  "application/json",
			Body:         []byte(msg),
		})
	util.FailOnError(err, "Failed to publish a message")
	log.Printf(" [x] Sent %s", string(msg))

	return mq
}
Example #3
0
/**
 * Binds Queues to Exchanges under a routing key
 */
func (mq *AMQP) BindQueuesToExchange(queues []string, exchange string, routing string) *AMQP {

	// Loop over exchanges
	for _, queue := range queues {

		// Bind MCP Queue to MCP exchange thru channel
		err := mq.Channel.QueueBind(
			queue,    // queue name
			routing,  // routing key
			exchange, // exchange
			false,
			nil,
		)
		util.FailOnError(err, "Failed to bind queue "+queue+" to exchange "+exchange+" with routing "+routing)
	}

	return mq
}
Example #4
0
/**
 * Register exchange dispatchers inside a channel
 */
func (mq *AMQP) RegisterExchanges(exchanges []string) *AMQP {

	// Loop over exchanges
	for _, exchange := range exchanges {

		// Declare exchange dispatcher
		err := mq.Channel.ExchangeDeclare(
			exchange, // name
			"topic",  // type
			true,     // durable
			false,    // auto-deleted
			false,    // internal
			false,    // no-wait
			nil,      // arguments
		)
		util.FailOnError(err, "Failed to declare into channel the exchange "+exchange)
	}

	return mq
}
Example #5
0
/**
 * Register Queues
 */
func (mq *AMQP) RegisterQueues(queues []string) *AMQP {

	// Loop over exchanges
	for _, queue := range queues {

		// Create MCP Inbound Queue
		q, err := mq.Channel.QueueDeclare(
			queue, // name
			true,  // durable
			false, // delete when unused
			false, // exclusive
			false, // no-wait
			nil,   // arguments
		)
		util.FailOnError(err, "Failed to declare queue "+queue)

		// Assign to struct map (hope it does not complain if it exists ...)
		mq.Queues[queue] = &q
	}

	return mq
}
Example #6
0
/**
 * Starts consuming messages into a queue
 */
func (mq *AMQP) Consume(queue string, fn func(models.QueueMessage, amqp.Delivery)) {

	// Consume queue messages
	deliveries, err := mq.Channel.Consume(
		queue, // queue
		"",    // consumer
		false, // auto-ack
		false, // exclusive
		false, // no-local
		false, // no-wait
		nil,   // args
	)
	util.FailOnError(err, "Failed to register consumer for queue "+queue)

	// Loop forever for messages, and call handler for each
	forever := make(chan bool)
	go func() {

		// Loop over deliveries
		for d := range deliveries {

			// Log message
			log.Printf("Received a message: %s", d.Body)

			// Parse received message
			msg := models.QueueMessage{}
			if err := json.Unmarshal([]byte(d.Body), &msg); err != nil {
				fmt.Println(err.Error())
				continue
			}

			// Call handler function
			go fn(msg, d)
		}
	}()
	log.Printf(" [*] Waiting for messages on queue %s. To exit press CTRL+C\n", queue)
	<-forever
}