假设你有一个文件init.js：

/*let isInitialized, browser, page, db, scraped_users

async function init() {
    if (!isInitialized) {
    browser = await puppeteer.launch()
    page = await browser.newPage()
    db = await MongoClient.connect("mongodb://localhost:27017/bot")
    scraped_users = db.collection("scraped_users")
    isInitialized = true
    }
    return { browser, page, db, scraped_users }
}

module.exports = init*/

let common = {}; //store some global's.

//this should only be called once, eg. when App starts
common.init = async function () {
    this.browser = await puppeteer.launch()
    this.page = await this.browser.newPage()
    this.db = await MongoClient.connect("mongodb://localhost:27017/bot")
    this.scraped_users = this.db.collection("scraped_users")
}

module.exports = common;

然后像这样使用它：

/*const init = require('./init.js')

init().then(({browser, page, db, scraped_users}) => {
    console.log(browser, page, db, scraped_users)
})*/

const common = require('./common');
const doSomething = require('./do-something');

async function run() {
    await common.init(); //this only needs to be done once
    console.log(common.browser); //etc
    await doSomething();
}

//now inside other units, eg. do-something.js
const common = require('./common');
async function doSomething() {
    console.log(common.browser); 
}