How to hash two password simultaneously using bcyrpt? - node.js

Question

I am trying to get login page with two passwords. For only one password the code is working perfectly but when I am adding another password it is throwing error "parallel Save Error".
[0] (node:16516) UnhandledPromiseRejectionWarning: ParallelSaveError: Can't save() the same
doc multiple times in parallel. Document: 5e703180c90fbc40848fcfca
[0] (node:16516) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated
either by throwing inside of an async function without a catch block, or by rejecting a promise which
was not handled with .catch(). (rejection id: 2)
[0] (node:16516) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated.
In the future, promise rejections that are not handled will terminate the Node.js process with a non-
zero exit code.
This is my user.js script:
const express = require('express');
const router = express.Router();
const bcrypt = require('bcryptjs');
const config = require('config');
const jwt = require('jsonwebtoken');
const User = require('../../models/User');
router.post('/', (req, res,) => {
const { name, email, password1, password2 } = req.body;
if(!name || !email || !password1 || !password2) {
return res.status(400).json({ msg: 'Please enter all fields' });
}
User.findOne({ email })
.then(user => {
if(user) return res.status(400).json({ msg: 'User already exists' });
const newUser = new User({
name,
email,
password1,
password2
});
// Hash
bcrypt.genSalt(10, (err, salt) => {
bcrypt.hash(newUser.password1, salt , (err, hash) => {
if(err) throw err;
newUser.password1 = hash;
newUser.save()
.then(user => {
jwt.sign(
{ id: user.id },
config.get('jwtSecret'),
{ expiresIn: 3600 },
(err, token) => {
if(err) throw err;
res.json({
token,
user: {
id: user.id,
name: user.name,
email: user.email
}
});
}
)
});
})
})
// Create salt & hash
bcrypt.genSalt(10, (err, salt) => {
bcrypt.hash(newUser.password2, salt, (err, hash) => {
if(err) throw err;
newUser.password2 = hash;
newUser.save()
.then(user => {
jwt.sign(
{ id: user.id },
config.get('jwtSecret'),
{ expiresIn: 3600 },
(err, token) => {
if(err) throw err;
res.json({
token,
user: {
id: user.id,
name: user.name,
email: user.email
}
});
}
)
});
})
})
})
});
module.exports = router;
and the following is the code for Authentication.js
const express = require('express');
const router = express.Router();
const bcrypt = require('bcryptjs');
const config = require('config');
const jwt = require('jsonwebtoken');
const auth = require('../../middleware/auth');
// User Model
const User = require('../../models/User');
router.post('/', (req, res) => {
const { email, password1, password2 } = req.body;
// for validation
if(!email || !password1 || !password2) {
return res.status(400).json({ msg: 'Please enter all fields' });
}
// Check if user exists
User.findOne({ email })
.then(user => {
if(!user) return res.status(400).json({ msg: 'User Does not exist' });
// Validation of password
bcrypt.compare(password1, user.password1)
.then(isMatch => {
if(!isMatch) return res.status(400).json({ msg: 'Invalid credentials' });
jwt.sign(
{ id: user.id },
config.get('jwtSecret'),
{ expiresIn: 3600 },
(err, token) => {
if(err) throw err;
res.json({
token,
user: {
id: user.id,
name: user.name,
email: user.email
}
});
}
)
})
bcrypt.compare(password2, user.password2)
.then(isMatch => {
if(!isMatch) return res.status(400).json({ msg: 'Invalid credentials' });
jwt.sign(
{ id: user.id },
config.get('jwtSecret'),
{ expiresIn: 3600 },
(err, token) => {
if(err) throw err;
res.json({
token,
user: {
id: user.id,
name: user.name,
email: user.email
}
});
}
)
})
})
})
router.get('/user', auth, (req, res) => {
User.findById(req.user.id)
.select('-password1, -password2')
.then(user => res.json(user));
});
module.exports = router;
I am getting only password2 as a hashed password.
password1:"ddd"
password2:"$2a$10$PQhBiDtelKoRspAFn7BW0OuI0pnAyDl.DQSag6bBvYdlirBZM/oAq"
what should I need to do to remove these errors?

Answer 1

I got the answer of above problem...
just need to change the following part in user.js. no need to create hash twice.
bcrypt.genSalt(10, (err, salt) => {
bcrypt.hash(newUser.password1, salt , async (err, hash) => {
bcrypt.hash(newUser.password2, salt, async (err, hash) => {
if(err) throw err;
newUser.password1 = hash;
newUser.password2 = hash;
await newUser.save()
...
...
same need to do in the athentication.js script.
bcrypt.compare(password1, user.password1)
bcrypt.compare(password2, user.password2)
.then(isMatch => {
if(!isMatch) return res.status(400).json({ msg: 'Invalid credentials'
});
jwt.sign(
{ id: user.id },
...
...

Answer 2

I think it's better to write the encrypt password method in the model.js and export it with the User to the route.js or whatever its name for better & clean code so you can use your method as long as you need.