如何将MQTT消息事件发回REST body？

const mqtt = require('mqtt');
const axios = require('axios');

// MQTT连接配置
const mqttBroker = 'mqtt://mqtt.example.com';
const mqttTopic = 'example/topic';

// REST API接口配置
const restApiUrl = 'https://api.example.com/endpoint';

// 连接到MQTT代理
const client = mqtt.connect(mqttBroker);

// 订阅MQTT主题
client.on('connect', () => {
  client.subscribe(mqttTopic);
});

// 接收到MQTT消息时触发回调函数
client.on('message', (topic, message) => {
  // 将MQTT消息转换为REST请求的body
  const requestBody = {
    topic: topic,
    message: message.toString()
  };

  // 发送REST请求
  axios.post(restApiUrl, requestBody)
    .then(response => {
      console.log('REST response:', response.data);
    })
    .catch(error => {
      console.error('REST error:', error);
    });
});