instaamqp

Instana instrumentation for streadway-amqp

This module contains instrumentation code for RabbitMQ clients written with streadway-amqp.

Installation

To add the module to your go.mod file run the following command in your project directory:

$ go get github.com/mier85/go-sensor/instrumentation/instaamqp

Usage

instaamqp offers a function wrapper around amqp.Channel that returns an instaamqp.AmqpChannel instance. This Instana object provides instrumentation for the amqp.Channel.Publish and amqp.Channel.Consume methods, that are responsible for tracing data from messages sent and received.

For any other amqp.Channel methods, the original amqp.Channel instance can be normally used.

A publisher example:

func Example_publisher() {
	exchangeName := "my-exchange"
	url := "amqp://guest:guest@localhost:5672/"

	// Create the Instana sensor
	sensor := instana.NewSensor("rabbitmq-client")

	c, err := amqp.Dial(url)
	failOnError(err, "Could not connect to the server")
	defer c.Close()

	ch, err := c.Channel()
	failOnError(err, "Could not acquire the channel")
	defer ch.Close()

	err = ch.ExchangeDeclare(exchangeName, "fanout", true, false, false, false, nil)
	failOnError(err, "Could not declare the exchange")

	// There must be an entry span per publish call.
	// In most common cases, creating an entry span manually is not needed, as the entry span is originated from an
	// incoming HTTP client call.
	entrySpan := sensor.Tracer().StartSpan("my-publishing-method")
	ext.SpanKind.Set(entrySpan, ext.SpanKindRPCServerEnum)

	// We wrap the original amqp.Channel.Publish and amqp.Channel.Consume methods into an Instana object.
	instaCh := instaamqp.WrapChannel(sensor, ch, url)

	// Use the Instana `Publish` method with the same arguments as the original `Publish` method, with the additional
	// `entrySpan` argument. That's it!
	err = instaCh.Publish(entrySpan, exchangeName, "", false, false, amqp.Publishing{
		ContentType: "text/plain",
		Body:        []byte(fmt.Sprintf("My published message")),
	})

	failOnError(err, "Error publishing the message")
	entrySpan.Finish()
}

A consumer example:

func Example_consumer() {
	exchangeName := "my-exchange"
	queueName := "my-queue"
	url := "amqp://guest:guest@localhost:5672/"

	sensor := instana.NewSensor("rabbitmq-client")

	c, err := amqp.Dial(url)
	failOnError(err, "Could not connect to the server")
	defer c.Close()

	ch, err := c.Channel()
	failOnError(err, "Could not acquire the channel")
	defer ch.Close()

	err = ch.ExchangeDeclare(exchangeName, "fanout", true, false, false, false, nil)
	failOnError(err, "Could not declare the exchange")

	q, err := ch.QueueDeclare(queueName, false, false, true, false, nil)
	failOnError(err, "Could not declare queue")

	err = ch.QueueBind(q.Name, "", exchangeName, false, nil)
	failOnError(err, "Could not bind the queue to the exchange")

	instaCh := instaamqp.WrapChannel(sensor, ch, url)

	// Use the Instana `Consume` method with the same arguments as the original `Consume` method.
	msgs, err := instaCh.Consume(q.Name, "", true, false, false, false, nil)
	failOnError(err, "Could not consume messages")

	forever := make(chan bool)

	go func() {
		for d := range msgs {
			fmt.Println("Got a message:", string(d.Body))
		}
	}()

	<-forever
}

See the instaamqp package documentation for detailed examples.