bcryptjs Illegal arguments: undefined, number

Question

i am getting an error like below and i tried to google it but i can't fix it

i am using bcryptjs library to encrypt password but it is not able to encrypt and send to sever

Error type

error Error: Illegal arguments: undefined, number at _async (webpack-internal:///(rsc)/./node_modules/bcryptjs/dist/bcrypt.js:170:47) at eval (webpack-internal:///(rsc)/./node_modules/bcryptjs/dist/bcrypt.js:176:13) at new Promise () at bcrypt.hash (webpack-internal:///(rsc)/./node_modules/bcryptjs/dist/bcrypt.js:175:23) at POST (webpack-internal:///(rsc)/./src/app/api/auth/register/route.ts:17:82) at process.processTicksAndRejections (node:internal/process/task_queues:95:5) at async eval (webpack-internal:///(rsc)/./node_modules/next/dist/server/future/route-modules/app-route/module.js:253:37)

my code

route.ts

import User from '../../../../../models/User';
import connect from '../../../../../server/database';
import bcrypt from 'bcryptjs';
import { NextResponse } from 'next/server';

export const POST = async (request) => {
  const { name, email, password } = await request.json();

  await connect();

  const hashedPassword = await bcrypt.hash(password, 5);

  const newUser = new User({
    name,
    email,
    password: hashedPassword,
  });

  try {
    await newUser.save();
    return new NextResponse('User has been created', {
      status: 201,
    });
  } catch (err) {
    return new NextResponse(err.message, {
      status: 500,
    });
  }
};

user model

import mongoose from 'mongoose';
import postsSchema from './Posts';
import commentSchema from './Comment';

const userSchema = new mongoose.Schema(
  {
    name: {
      type: String,
      require: true,
    },
    userName: {
      type: String,
    },
    email: {
      type: String,
      unique: true,
      require: true,
    },
    password: {
      type: String,
      require: true,
    },
    registrationDate: {
      type: Date,
      default: Date.now,
    },
    avatar: {
      type: String,
    },
    admin: {
      type: Boolean,
      default: false,
      require: true,
    },
    birthDate: {
      type: Date,
    },
    posts: [postsSchema],
    comments: [commentSchema],
  },
  { timestamps: true },
);

export default mongoose.models.User || mongoose.model('User', userSchema);

package

{
  "name": "khuongviettai",
  "version": "0.1.0",
  "private": true,
  "scripts": {
    "dev": "next dev",
    "build": "next build",
    "start": "next start",
    "lint": "next lint"
  },
  "dependencies": {
    "@ckeditor/ckeditor5-build-classic": "^39.0.0",
    "@ckeditor/ckeditor5-react": "^6.1.0",
    "@types/node": "20.4.5",
    "@types/react": "18.2.18",
    "@types/react-dom": "18.2.7",
    "axios": "^1.4.0",
    "eslint": "8.46.0",
    "eslint-config-next": "13.4.12",
    "formik": "^2.4.3",
    "next": "13.4.12",
    "react": "18.2.0",
    "react-dom": "18.2.0",
    "swiper": "^10.1.0",
    "typescript": "5.1.6",
    "yup": "^1.2.0"
  },
  "devDependencies": {
    "@types/bcryptjs": "^2.4.2",
    "@types/react-google-recaptcha": "^2.1.5",
    "bcryptjs": "^2.4.3",
    "mongoose": "^7.4.2",
    "next-auth": "^4.22.3",
    "prettier": "^3.0.1",
    "sass": "^1.64.2"
  }
}

Answer 1

"Illegal arguments: undefined, number". Bcrypt is telling you password, 5 is received as undefined, number. This means password is undefined. Do a console.log(password) right after const { name, email, password } = await request.json(); and it should say undefined. If that's the case then there's an issue with how you send or catch the password variable.