我創建了一個新的貓鼬模型名稱“用戶”，并使用它創建了一個新對象以將新記錄保存到集合中。運行代碼后，我在 Mongo Atlas 中看不到任何集合。我使用 .once 檢查與 Mongo Atlas 的連接，但在運行并從 google auth 獲取我需要的配置文件后，我看不到在 Mongo 中制作的任何集合，也看不到我創建的對象中的任何記錄 - 使用未定義一個日志。index.jsconst express = require('express');const mongoose = require('mongoose');const keys = require('./config/keys');require('./models/User');require('./services/passport'); //const passportconfig <=const app = express();const { Router } = require('express');mongoose.connect(keys.mongoURI);const connection = mongoose.connection;connection.once('open',()=>{    console.log("MongoDB database connection established successfully");});require('./routes/authRoutes')(app); //authRoutes using app expressconst PORT = process.env.PORT || 5000;app.listen(PORT);用戶const mongoose = require('mongoose');//const { mongoURI } = require('../config/keys');//const Schema = mongoose.Schema;const {Schema} = mongoose; //same as line 2 => tell to mongoose object that he have a    property called Schema and use it in new object call Schemaconst userSchema = new Schema({ //constructor i    googleId: String //user will have googleId for now});mongoose.model('users', userSchema);//our new collection User and will follow by the userSchema => only creating collection if it dosent exsits only護照const passport = require('passport');const GoogleStrategy = require('passport-google-oauth20').Strategy;const keys = require('../config/keys');const mongoose = require('mongoose');const User = mongoose.model('users');passport.use(new GoogleStrategy({    clientID: keys.googleClientID,    clientSecret: keys.googleClientSecret,    callbackURL: '/auth/google/callback'},更改為 .save() 后；并添加箭頭功能：console.log('profile Id',profile.id);        new User({ googleId: profile.id}).save(err => {            console.log(err)         });在 .save(err =>) 我在終端中得到空輸出。添加 userNewUrlParser 后工作并保存到集合中：mongoose.connect(keys.mongoURI,{ useNewUrlParser: true });在 save(err=>) 函數的終端中仍然得到一個 - null