如何在本地数据库中使用 watch() 函数 mongoose？

watch() 函数在 socket.io 中使用时不起作用

const app = require('./app');
const moment = require('moment');
const dotenv = require('dotenv');
const mongoose = require('mongoose');
const User = require('./models/user');
const ChatRoom = require('./models/chatRoom');
const Message = require('./models/message');
dotenv.config({ path: './config.env' });
io.on('connection', async (socket) => {
  const user_id = socket.handshake.query['user_id'];
ChatRoom.watch().on("change", (data)=>{
    console.log(data);
  })
})

watch() 函数在 socket.io 中使用时不起作用