I get this error when registering a user:

(node:13225) UnhandledPromiseRejectionWarning: Error: Illegal arguments: undefined, string at Object.bcrypt.hashSync (/home/admin/Desktop/project/node_modules/bcryptjs/dist/bcrypt.js:189:19) at module.exports.register (/home/admin/Desktop/project/controllers/auth.js:26:30) (node:13225) 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: 1)

controller:

const bcrypt = require('bcryptjs')
const jwt = require('jsonwebtoken')
const db = require('../config/db.config.js')
const User = db.user
const errorHandler = require('../utils/errorHandler')

module.exports.register = async function(req, res) {
    const candidate = await User.findOne({
        where: {
            username: req.body.username
        }
    })

    if (candidate) {
        res.status(409).json({
            message: 'This login is already taken. Try another.'
        })
    } else {
        const salt = bcrypt.genSaltSync(10)
        const password = req.body.password
        const user = new User({
            name: req.body.name,
            username: req.body.username,
            roles: req.body.roles,
            photoSrc: req.file ? req.file.path: '',
            password: bcrypt.hashSync(password, salt)
        })
        try {
            await user.save()
            res.status(201).json(user)
        } catch(e) {
            errorHandler(res, e)
        }
    }
}

models:

module.exports = (sequelize, Sequelize) => {
    const User = sequelize.define('users', {
        name: {
            type: Sequelize.STRING(100),
            required: true
        },
        username: {
            type: Sequelize.STRING(40),
            required: true,
            unique: true
        },
        roles: {
            type: Sequelize.STRING(100),
            required: true
        },
        password: {
            type: Sequelize.STRING,
            required: true
        },
        photoSrc: {
            type: Sequelize.STRING(200),
            default: ''
        }
    });

    return User;
}

I get this error when registering a user:

(node:13225) UnhandledPromiseRejectionWarning: Error: Illegal arguments: undefined, string at Object.bcrypt.hashSync (/home/admin/Desktop/project/node_modules/bcryptjs/dist/bcrypt.js:189:19) at module.exports.register (/home/admin/Desktop/project/controllers/auth.js:26:30) (node:13225) 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: 1)

controller:

const bcrypt = require('bcryptjs')
const jwt = require('jsonwebtoken')
const db = require('../config/db.config.js')
const User = db.user
const errorHandler = require('../utils/errorHandler')

module.exports.register = async function(req, res) {
    const candidate = await User.findOne({
        where: {
            username: req.body.username
        }
    })

    if (candidate) {
        res.status(409).json({
            message: 'This login is already taken. Try another.'
        })
    } else {
        const salt = bcrypt.genSaltSync(10)
        const password = req.body.password
        const user = new User({
            name: req.body.name,
            username: req.body.username,
            roles: req.body.roles,
            photoSrc: req.file ? req.file.path: '',
            password: bcrypt.hashSync(password, salt)
        })
        try {
            await user.save()
            res.status(201).json(user)
        } catch(e) {
            errorHandler(res, e)
        }
    }
}

models:

module.exports = (sequelize, Sequelize) => {
    const User = sequelize.define('users', {
        name: {
            type: Sequelize.STRING(100),
            required: true
        },
        username: {
            type: Sequelize.STRING(40),
            required: true,
            unique: true
        },
        roles: {
            type: Sequelize.STRING(100),
            required: true
        },
        password: {
            type: Sequelize.STRING,
            required: true
        },
        photoSrc: {
            type: Sequelize.STRING(200),
            default: ''
        }
    });

    return User;
}

• javascript
• node.js

7 Answers 7

You need to apply await to your salt and password assignments too.

Like this,

const salt = await bcrypt.genSaltSync(10);
const password = await req.body.password;

Hope this helps!.

For every async operation, we have to await

const salt = await bcrypt.genSalt(10);
const hashedPassword = await bcrypt.hash(req.body.password, salt);

This happened with me when I was verifying my registration form, I was searching for the fix but didn't get a proper solution.

How I fixed it Later I realised that I have not passed the required fields before sending post request. Before Sending Post request through Postman make sure You have passed key and value in postman

Click on Above link to see example.

I was missing the "OTP" field in Schema

Old:

Schema({
  email: {
    type: String,
    requird: true,
  },
  createdAt: {
    type: Date,
    default: Date.now,
    index: { expires: 300 },
    // after 5 mins it get's deleted
  },
},
{ timestamps: true })

New:

Schema({
  email: {
    type: String,
    requird: true,
  },
  otp: {
    type: String,
    required: true,
  },
  createdAt: {
    type: Date,
    default: Date.now,
    index: { expires: 300 },
    // after 5 mins it get's deleted
  },
},
{ timestamps: true })

working for me like this way, instead of cb, you can use async-await

bcrypt.genSalt(10, function(err, salt) {
  bcrypt.hash("password", salt, function(err, hash) {
    // Store hash in your password DB.
  });
});

Thanks!!

I encountered the same error using lambda function, but the problem with me was parsing the req body so i had to

const body = JSON.parse(event.body) // in case of lambda function

hope this helps someone.

I faced the same problem. It was due to two issues:

1. I switched from bcryptjs to bcrypt, which worked perfectly for hashing:

const salt = await bcrypt.genSalt(10); // Generate salt  
const hashedPassword = await bcrypt.hash(password, salt);  

2. My database configuration was causing issues. I replaced node:sqlite with better-sqlite3, and it solved the problem:

import Database from "better-sqlite3";  

// Create or connect to a SQLite database file  
const db = new Database("mydatabase.sqlite");  

Try these solutions; they worked for me!