JAVASCRIPT

how to use compare password in node js

//required files
const express = require('express')
const router = express.Router();

//bcryptjs
const bcrypt = require('bcryptjs')

//User modal of mongoDB
const User = require('../../models/User')


//Post request for login
router.post('/', (req, res) => {
    //email and password
    const email = req.body.email
    const password = req.body.password

    //find user exist or not
    User.findOne({ email })
        .then(user => {
            //if user not exist than return status 400
            if (!user) return res.status(400).json({ msg: "User not exist" })

            //if user exist than compare password
            //password comes from the user
            //user.password comes from the database
            bcrypt.compare(password, user.password, (err, data) => {
                //if error than throw error
                if (err) throw err

                //if both match than you can do anything
                if (data) {
                    return res.status(200).json({ msg: "Login success" })
                } else {
                    return res.status(401).json({ msg: "Invalid credencial" })
                }

            })

        })

})

module.exports = router