【已解决】unicloud 云对象调用mqtt提示错误

请教如何解决 globalThis is not defined 错误

在云对象mqtt-publish目录下npm了mqtt.js
连接本地云函数调用正常
上传部署云端后，连接云端云函数，前端调用提示Uncaught (in promise) Error: [mqtt-publish]: globalThis is not defined 错误
云对象代码

async msgPublish(msg) {  
        const mqtt = require('mqtt');  
        let host = 'tcp://202.120.92.203:1883';  
        let publishTopic = '/vaeb9Ypj/O5YVteYn/data';  
        let  clientId = "mqtt_1";  
        let client = null;  
        if (client == null || client.connented == false) {  
            console.log('in if code')  
            client = mqtt.connect(host, {  
                clientId,  
                clean: true,  
                connectTimeout: 4000,  
                username: 'O5YVteYn',  
                password: 'CU2b5ZfP',  
            });  
            client.on('connect', () => {  
                const message1 = JSON.stringify(msg)  
                client.publish(publishTopic, message1, error => {  
                    // console.log(error || '消息发布成功');  
                    if (error) {  
                        console.log(error)  
                    } else {  
                        console.log('消息发布成功');  
                        client.end();  
                    }  
                })  
            });  
        }  
        return {  
            code: 200  
        };  
    }

前端代码

methods: {  
            send() {  
                cloud.msgPublish({  
                    data: "hello world"  
                }).then(res=>{  
                    console.log(res)  
                })  
            }  
        }