微信小程序通过mqtt控制esp32

1.注册巴法云

2.设备连接mqtt

3.微信小程序

备注

本文esp32用的是MicroPython固件，MQTT服务用的是巴法云。

本文参考巴法云官方教程：https://bemfa.blog.csdn.net/article/details/115282152

1.注册巴法云

注册登陆并新建一个topic，注意是MQTT设备云。

2.设备连接mqtt

代码如下，以点亮esp32设备上的蓝色灯举例，订阅上一步创建的topic，当设备从mqtt服务器收到“on”时，灯亮，收到“off”时灯灭。

from umqtt.simple import MQTTClient
import time
from machine import Timer, Pin# 需要修改的地方
wifiName = "***"  # wifi 名称，不支持5G wifi
wifiPassword = "***"  # wifi 密码
clientID = "***"  # Client ID ，密钥，巴法云控制台获取
myTopic = "topic"  # 需要订阅的主题值，巴法MQTT控制台创建# 默认设置
serverIP = "bemfa.com"  # mqtt 服务器地址
port = 9501
led_pin = Pin(2, Pin.OUT)# WIFI 连接函数
def do_connect():import networksta_if = network.WLAN(network.STA_IF)if not sta_if.isconnected():print("connecting to network...")sta_if.active(True)sta_if.connect(wifiName, wifiPassword)while not sta_if.isconnected():passprint("connect  WiFi ok")# 接收消息，并处理
def MsgOK(topic, msg):  # 回调函数，用于收到消息print((topic, msg))  # 打印主题值和消息值if topic == myTopic.encode():  # 判断是不是发给myTopic的消息if msg == b"on":  # 当收到onprint("rec on")led_pin.value(1)elif msg == b"off":  #  当收到offprint("rec off")led_pin.value(0)# 初始化mqtt连接配置
def connect_and_subscribe():client = MQTTClient(clientID, serverIP, port, keepalive=60)client.set_callback(MsgOK)try:client.connect()print("MQTT connected!")except Exception as e:print("MQTT connect failed:", e)client.subscribe(myTopic, qos=0)print("Connected to %s" % serverIP)return clientdef restart_and_reconnect():print("Failed to connect to MQTT broker. Reconnecting...")time.sleep(10)machine.reset()# 开始连接WIFI
do_connect()# 开始连接MQTT
try:client = connect_and_subscribe()
except OSError as e:restart_and_reconnect()# 全局变量记录定时器状态
timer_running = False# 定时器函数
def send_ping(t):client.ping()print("Ping sent!")# 初始化定时器
def init_timer():global timer_runningif not timer_running:timer = Timer(-1)timer.init(period=30000, mode=Timer.PERIODIC, callback=send_ping)timer_running = True# 程序启动时初始化定时器
init_timer()while True:try:client.check_msg()except OSError as e:  # 如果出错就重新启动print("Failed to connect to MQTT broker. Reconnecting...")restart_and_reconnect()

3.微信小程序

在微信小程序中，通过wxs连接mqtt，核心代码如下：

data: {uid:"******",//用户密钥，巴法云控制台获取ledtopic:"topic",//主题，mqtt控制台创建client: null,//mqtt客户端，默认为空},mqttConnect(){var that = this//MQTT连接的配置var options= {keepalive: 60, //60s ，表示心跳间隔clean: true, //cleanSession不保持持久会话protocolVersion: 4, //MQTT v3.1.1clientId:this.data.uid}//初始化mqtt连接this.data.client = mqtt.connect('wxs://bemfa.com:9504/wss',options)// 连接mqtt服务器this.data.client.on('connect', function () {console.log('连接服务器成功')})//接收消息that.data.client.on('message', function (topic, message) {console.log(topic)var  msg = message.toString()//打印消息console.log('收到消息：'+msg)})//断线重连this.data.client.on("reconnect", function () {console.log("重新连接")});}

在小程序中添加一个按钮来往指定topic发送on/off消息，这样你的设备在收到相应的消息之后，上面的灯会点亮/熄灭。

  onChange({ detail }){//detail是滑块的值，检查是打开还是关闭，并更换正确图标this.setData({ checked: detail,});if(detail == true){//如果是打开操作this.data.client.publish(this.data.ledtopic, 'on')//mqtt推送onthis.setData({ ledicon: "/utils/img/lighton.png",//设置led图片为on});}else{this.data.client.publish(this.data.ledtopic, 'off')//mqtt推送offthis.setData({ ledicon: "/utils/img/linghtoff.png",//设置led图片为off});}}

完整的小程序项目代码参考：点此下载

在巴法云控制台可以看到小程序发送的消息记录：