### 訂閱模式 消息被路透投遞給多個隊列,一個消息被多個消費者獲取.  ### 特點 1. 需要聲明交換機. 2. 交換機類型為fanout. 2. 不需要routingKey. 3. 需要匿名隊列.(是否需要自動刪除) 4. 將匿名隊列和交換機綁定. ### 實例 ~~~ const MQURL = "amqp://guest:guest@localhost:5672" type RabbitMQ struct { conn *amqp.Connection channel *amqp.Channel Exchange string //交換機名 Queue string //隊列名 Key string //路由名 AMQPUrl string //連接URL } //創建rabbit實例 func New(exchange, queue, key string) *RabbitMQ { r := &RabbitMQ{ Exchange: exchange, Queue: queue, Key: key, AMQPUrl: MQURL, } var err error r.conn, err = amqp.Dial(r.AMQPUrl) // :=不能用于結構體賦值 r.FailOnErr(err, "創建Connection失敗") r.channel, err = r.conn.Channel() r.FailOnErr(err, "創建channel失敗") return r } //處理錯誤 func (r *RabbitMQ) FailOnErr(err error, msg string) { if err != nil { fmt.Printf("%s : %s\n", err, msg) return } } //創建訂閱模式的實例 func NewRabbitMQPubSub(exchange string) *RabbitMQ { r := New(exchange, "", "") //隊列名稱為空 var err error r.conn, err = amqp.Dial(r.AMQPUrl) r.FailOnErr(err, "創建connection失敗") r.channel, err = r.conn.Channel() r.FailOnErr(err, "創建channel失敗") return r } //訂閱模式發布 func (r *RabbitMQ) PublishPub(message string) { //嘗試創建交換機 err := r.channel.ExchangeDeclare( r.Exchange, amqp.ExchangeFanout, //訂閱類型的交換機是fanout true, false, false, false, nil, ) r.FailOnErr(err, "創建路由器失敗") r.channel.Publish( r.Exchange, "", //key是為空的 false, false, amqp.Publishing{ ContentType: "text/plain", Body: []byte(message), }) } //消費 func (r *RabbitMQ) ConsumePub() { err := r.channel.ExchangeDeclare( r.Exchange, amqp.ExchangeFanout, true, false, false, false, nil, ) if err != nil { r.FailOnErr(err, "創建交換機失敗") } //創建隊列 q, err := r.channel.QueueDeclare( "", //隊列名稱為空 true, false, false, false, nil, ) r.FailOnErr(err, "創建隊列失敗") r.channel.QueueBind( q.Name, //綁定隨機生成的隊列名稱 "", //pubsub模式下,這里的key為空 r.Exchange, false, nil, ) msg, err := r.channel.Consume( q.Name, "", true, false, false, false, nil, ) forever := make(chan struct{}) go func() { for v := range msg { fmt.Println(string(v.Body)) } }() fmt.Println("等待接受消息") <-forever } ~~~ 消費端 ~~~ r :=rabbitmq.NewRabbitMQPubSub("test") r.ConsumePub() ~~~ 產生端 ~~~ r := rabbitmq.NewRabbitMQPubSub("test") for i := 0; i < 100; i++ { r.PublishPub("hello: " + strconv.Itoa(i)) } ~~~ 同樣的消息,多個消費端都可以收到.