golang mqtt demo

package libs import ( "fmt" "log" "os" "time" mqtt "github.com/eclipse/paho.mqtt.golang" ) func InitMQTT(server string, username string, password string, MQTTClientID string) (mqttClient mqtt.Client, err error) { opt := mqtt.NewClientOptions() opt.AddBroker(server) opt.SetUsername(username) opt.SetPassword(password) opt.SetClientID(MQTTClientID) opt.SetConnectTimeout(time.Second * 3) opt.SetAutoReconnect(true) opt.SetConnectRetry(true) opt.SetConnectRetryInterval(time.Second) opt.SetOrderMatters(false) opt.SetOnConnectHandler(func(client mqtt.Client) { // 连接被建立后的回调函数 log.Println("Mqtt is connected!", "clientId:", MQTTClientID, "server:", server) }) opt.SetConnectionLostHandler(func(client mqtt.Client, err error) { // 连接被关闭后的回调函数 log.Println("Mqtt is disconnected!", "clientId:", MQTTClientID, "reason", err.Error()) }) mqttClient = mqtt.NewClient(opt) if token := mqttClient.Connect(); token.Wait() && token.Error() != nil { fmt.Printf("mqtt连接失败: %v\n", token.Error()) os.Exit(1) } return } func InitMQTTAndSubscribe(server string, username string, password string, MQTTClientID string, topic string, callback mqtt.MessageHandler) (mqttClient mqtt.Client, err error) { opt := mqtt.NewClientOptions() opt.AddBroker(server) opt.SetUsername(username) opt.SetPassword(password) opt.SetClientID(MQTTClientID) opt.SetConnectTimeout(time.Second * 3) opt.SetAutoReconnect(true) opt.SetConnectRetry(true) opt.SetConnectRetryInterval(time.Second) opt.SetOrderMatters(false) opt.SetOnConnectHandler(func(client mqtt.Client) { // 连接被建立后的回调函数 log.Println("Mqtt is connected!", "clientId:", MQTTClientID, "server:", server) if token := client.Subscribe(topic, 0, callback); token.Wait() && token.Error() != nil { fmt.Printf("订阅失败: %v\n", token.Error()) os.Exit(1) } }) opt.SetConnectionLostHandler(func(client mqtt.Client, err error) { // 连接被关闭后的回调函数 log.Println("Mqtt is disconnected!", "clientId:", MQTTClientID, "reason", err.Error()) }) mqttClient = mqtt.NewClient(opt) if token := mqttClient.Connect(); token.Wait() && token.Error() != nil { fmt.Printf("mqtt连接失败: %v\n", token.Error()) os.Exit(1) } return }