Node.js 我想检查我是否已经存储了数据，如果没有，那么我想将其存储在我的mongodb数据库中

这是我正在使用的代码，因此如果我发现一个文档具有相同的uuid，我不想保存它

const mongoose = require('mongoose');
mongoose.connect("mongodb+srv://connection string", {useNewUrlParser: true});
var db = mongoose.connection;
const Meeting = mongoose.model('Meeting',
  {
    host_id: String,
    topic: String,
    type: Number,
    start_time: String,
    duration: Number,
    timezone: String,
    created_at: String,
    join_url: String,
    agenda: String,
  });
        //STEP 4
        //we can now use the access token to make API calls
        request.get('https://api.zoom.us/v2/users/'+email+'/meetings', function (error, response, body) {
          if (error) {
            console.log('Error in API ', error)
          } else {
            body = JSON.parse(body);
            //display response in console
            console.log('API call ', body);       
            //save in db
            for (const m of body.meetings) {
             // m=JSON.parse(m);
              if(db.meeting.countDocuments({'uuid': m.uuid}, { limit: 1 })==0{
                let meeting = new Meeting(m);
                meeting.save();
              }
            }

          }

但我得到的错误是：

---

TypeError:无法读取未定义的属性“countDocuments”。

查找具有特定uuid的文档的非常基本的请求，如果它不存在，请保存它

Meeting.findOne({'uuid': uuid}, (err, existingMeeting) => {
    if (err) { 
      /* handle the error
      return / send a response */
    }
    if (existingMeeting) {
      /* handle the existence of this uuid
      return / send a response */
    }
    Meeting.save((err) => {
      if (err) { 
      /* handle the error in saving
      return / send a response */
      }
      /* everything has saved
      return / send a response */
    });
});

---

好的，我用express来做，所以我的解决方案是： 只有一个问题，我不明白那封

电子邮件是从哪里来的

const express = require("express");
const router = express.Router();


 router.get('https://api.zoom.us/v2/users/'+email+'/meetings', (req, res) => 
    {
    const { uuid } = req.body; 


    //check existing meeting
    Meeting.findOne({ uuid}).then(meeting => {
      if (meeting) return res.status(400).json({ meeting: "The Meeting with this Id is already exist" });

    });
});

你能分享关于这个for循环的全部代码（在这里你定义了“body”及其属性）并分享模型模式吗？我编辑了我的文章。请看一下。检查我的答案