Question

我通过端口8081（websockets）建立了MQTT连接。 on消息接收回调除了我在脚本开头发送的“ test”消息外，不显示任何其他消息：

function onConnect() {
  // Once a connection has been made, make a subscription and send a message.
  console.log("onConnect");
  mqtt.subscribe("drivingStatus");
  message = new Paho.Message("test");
  message.destinationName = "drivingStatus";
  mqtt.send(message);
}

此消息“测试”出现在onMessagedArrived函数中：

function onMessageArrived(message) {
  console.log(message.payloadString)
  // console.log("onMessageArrived:"+message.payloadString);
}

但是，当消息从python脚本（目标端口1883）发布到主题“ drivingStatus”时，该消息不会出现在控制台中。尽管该消息出现在MQTT经纪人控制台上。

Javascript Paho MQTT连接如何与MQTT代理正确同步？

预期的输出是所有消息都将显示在控制台中（如在输入命令mosquitto_sub -d -t drivingStatus后通过终端订阅时所看到的那样）

整个代码是：

var mqtt
var reconnectTimeout = 2000
var host = "x"
var port = 8081


var r = Math.random().toString(36).substring(7);
        var client = "hmack00" + r 
function onConnect() {
  // Once a connection has been made, make a subscription and send a message.
  console.log("onConnect");
  mqtt.subscribe("drivingStatus");
  message = new Paho.Message("test");
  message.destinationName = "drivingStatus";
  mqtt.send(message);
}

function onFailure(message) {
  console.log("Connection Attempt to Host "+host+"Failed");
  setTimeout(MQTTconnect, reconnectTimeout);
}

function onMessageArrived(message) {
  console.log(message.payloadString)
  // console.log("onMessageArrived:"+message.payloadString);
}

mqtt = new Paho.Client(host, port, client);
console.log("connecting to " + host)
var options = {
  timeout: 3,
  onSuccess: onConnect,
  onFailure: onFailure,
};

mqtt.onMessageArrived = onMessageArrived;
mqtt.connect(options);

仅在本地发送时，才会显示主题的Javascript MQTT Broker消息

0 个答案: