This code reports an errorvar queryAll = user_model.find();, I don’t know where the error is in this code, please help someone with experience,

// login action const express = require('express'); var mongoose = require('mongoose'); var User_Model = mongoose.model('User_Model'); const router = express.Router(); router.get('/',(req,res,next)=>{ res.render('login.html'); }); module.exports=router; router.post('/',(req,resp,next)=>{ debugger; //连接数据库 mongoose.connect('mongodb://127.0.0.1:27017/likeread',(err)=>{ if(err) console.log('err'); }); console.log(mongoose); var user_model = new User_Model(); debugger; //查找数据 var queryAll = user_model.find({}); queryAll.exec((err,result)=>{ if(err){ console.log(err); }else{ console.log(result); } }); debugger; user_model.close((err,res)=>{ if(err){ console.log(err); } }); debugger; resp.end(); });