RabbitMQ HelloWorld

1. hello world

生成者代码

package main

import (
	"github.com/streadway/amqp"
	"log"
)

func failOnError(err error, msg string) {
	if err != nil {
		log.Fatalf("%s: %s", msg, err)
	}
}

func main() {
	conn, err := amqp.Dial("amqp://admin:admin@localhost:5672/")
	failOnError(err, "Failed to connect to RabbitMQ")
	defer conn.Close()

	ch, err := conn.Channel()
	failOnError(err, "Failed to open a channel")
	defer ch.Close()

	q, err := ch.QueueDeclare(
		"hello", // name
		false,   // durable
		false,   // delete when unused
		false,   // exclusive
		false,   // no-wait
		nil,     // arguments
	)
	failOnError(err, "Failed to declare a queue")

	body := "Hello World!"
	err = ch.Publish(
		"",
		q.Name,
		false,
		false,
		amqp.Publishing{
			ContentType: "text/plain",
			Body:        []byte(body),
		})
	failOnError(err, "Failed to publish a message")
}

消费者代码

package main

import (
	"github.com/streadway/amqp"
	"log"
)

func failOnError(err error, msg string) {
	if err != nil {
		log.Fatalf("%s: %s", msg, err)
	}
}

func main() {
	conn, err := amqp.Dial("amqp://lsz:lsz@localhost:5672/")
	failOnError(err, "Failed to connect to RabbitMQ")
	defer conn.Close()

	ch, err := conn.Channel()
	failOnError(err, "Failed to open a channel")
	defer ch.Close()

	q, err := ch.QueueDeclare(
		"hello", // name
		false,   // durable
		false,   // delete when unused
		false,   // exclusive
		false,   // no-wait
		nil,     // arguments
	)
	failOnError(err, "Failed to declare a queue")

	msgs, err := ch.Consume(
		q.Name, // queue
		"",     // consumer
		true,   // auto-ack
		false,  // exclusive
		false,  // no-local
		false,  // no-wait
		nil,    // args
	)
	failOnError(err, "Failed to register a consumer")

	forever := make(chan bool)

	go func() {
		for d := range msgs {
			log.Printf("Received a message: %s", d.Body)
		}
	}()

	log.Printf(" [*] Waiting for messages. To exit press CTRL+C")
	<-forever
}

消费者代码中，等待其他其他goroutine介绍使用的无缓冲的chan(实质是利用了无缓存管道的阻塞), sync.WaitGroup也可以是实现