mqtt增加心跳间隔应对网络波动

utils/mqtt.js

@@ -191,7 +191,8 @@ class MqttClient {
 
 		try {
 			const connectOptions = {
-				timeout: 4,
+				timeout: 10, // 增加连接超时时间，应对网络波动
+				keepAliveInterval: 30, // 明确设置心跳间隔为30秒
 				userName: this.options.username,
 				password: this.options.password,
 				useSSL: false,