Add demo of go

lmq-go-demo/lmqdemo.go

@@ -0,0 +1,78 @@
+package main
+
+import (
+	"crypto/hmac"
+	"crypto/sha1"
+	"encoding/base64"
+	"fmt"
+	"log"
+	"os"
+	"time"
+
+	mqtt "github.com/eclipse/paho.mqtt.golang"
+)
+
+const (
+	topic      = "test"     //测试收发消息的 Topic
+	instanceID = "XXXX"     //实例 ID，购买后从控制台获取
+	accessKey  = "XXXX"     //账号 AccessKey，从账号控制台获取
+	secretKey  = "XXXX"     //账号 SecretKey，从账号控制台获取
+	groupID    = "GID-XXXX" //客户端使用的 GroupID，从控制台申请
+	deviceID   = "XXXX"     //客户端 ClientID 的后缀，由业务自行指定，只需要保证全局唯一即可
+)
+
+func PublishHandler(client mqtt.Client, msg mqtt.Message) {
+	log.Printf("TOPIC: %s\n", msg.Topic())
+	log.Printf("MSG: %s\n", msg.Payload())
+}
+
+func OnConnectHandler(client mqtt.Client) {
+	log.Println("connect success")
+
+	if token := client.Subscribe(topic, 0, nil); token.Wait() && token.Error() != nil {
+		fmt.Println(token.Error())
+		os.Exit(1)
+	}
+
+	time.AfterFunc(time.Millisecond*100, func() {
+		text := fmt.Sprintf("hello mqtt demo")
+		token := client.Publish(topic, 0, false, text)
+		token.Wait()
+	})
+}
+
+func main() {
+	//ClientID要求使用 GroupId 和 DeviceId 拼接而成，长度不得超过64个字符
+	clientID := fmt.Sprintf("%s@@@%s", groupID, deviceID)
+
+	host := fmt.Sprintf("tcp://%s.mqtt.aliyuncs.com:1883", instanceID)
+	opts := mqtt.NewClientOptions().AddBroker(host)
+
+	opts.SetClientID(clientID)
+	opts.SetOnConnectHandler(OnConnectHandler)
+	opts.SetDefaultPublishHandler(PublishHandler)
+	opts.SetCleanSession(true)
+
+	//username和 Password 签名模式下的设置方法，参考文档 https://help.aliyun.com/document_detail/48271.html?spm=a2c4g.11186623.6.553.217831c3BSFry7
+	username := fmt.Sprintf("Signature|%s|%s", accessKey, instanceID)
+	opts.SetUsername(username)
+
+	mac := hmac.New(sha1.New, []byte(secretKey))
+	mac.Write([]byte(clientID))
+	password := base64.StdEncoding.EncodeToString(mac.Sum(nil))
+	opts.SetPassword(password)
+
+	c := mqtt.NewClient(opts)
+	if token := c.Connect(); token.Wait() && token.Error() != nil {
+		panic(token.Error())
+	}
+
+	time.Sleep(time.Second * 1)
+
+	if token := c.Unsubscribe(topic); token.Wait() && token.Error() != nil {
+		fmt.Println(token.Error())
+		os.Exit(1)
+	}
+
+	c.Disconnect(250)
+}