Try to compare Password using mongoose and bcrypt in typescript

Question

I am getting the following error in line 40:

    bcrypt.compare(candidatePassword, this.password, function (err, isMatch) {
                                      ~~~~~~~~~~~~~

Argument of type 'Function' is not assignable to parameter of type 'string'.ts(2345)

According to the IUser it should be as string and i have no idea why ts means it is a function.

The complete file:

import { Schema, Document } from 'mongoose';
import bcrypt from 'bcrypt';

const salt: number = 12;

const UserSchema: Schema<IUser> = new Schema({
    email: {
        type: String,
        required: true,
        unique: true,
    },
    name: {
        type: String,
        required: true,
        minlength: 3,
        maxlength: 32,
    },
    password: {
        type: String,
        required: true,
    },
});

// * Hash the password befor it is beeing saved to the database
UserSchema.pre('save', function (next: (err: Error | null) => void) {
    // * Make sure you don't hash the hash
    if (!this.isModified('password')) {
        return next(null);
    }
    bcrypt.hash(this.password, salt, (err: Error, hash: String) => {
        if (err) return next(err);
        this.password = hash;
    });
});

UserSchema.methods.comparePasswords = function (
    candidatePassword: String,
    next: (err: Error | null, same: Boolean | null) => void,
) {
    bcrypt.compare(candidatePassword, this.password, function (err, isMatch) {
        if (err) {
            return next(err, null);
        }
        next(null, isMatch);
    });
};

export interface IUser extends Document {
    email: String;
    name: String;
    password: String;
}

This question may help you: . – lu4ezar Jan 24 '21 at 14:19 — lu4ezar, Jan 24 '21 at 14:19

score 3 · Accepted Answer · answered Jan 04 '21 at 09:30

The basic types of TypeScript are: string, boolean, number etc. see Basic Types. But you are using the constructors(String, Boolean etc.) of JavaScript data types. See JavaScript data types and data structures

The correct way:

import { Schema, Document } from 'mongoose';
import bcrypt from 'bcrypt';

const salt: number = 12;

const UserSchema: Schema<IUser> = new Schema({
  email: {
    type: String,
    required: true,
    unique: true,
  },
  name: {
    type: String,
    required: true,
    minlength: 3,
    maxlength: 32,
  },
  password: {
    type: String,
    required: true,
  },
});

// * Hash the password befor it is beeing saved to the database
UserSchema.pre('save', function (this: IUser, next: (err?: Error | undefined) => void) {
  // * Make sure you don't hash the hash
  if (!this.isModified('password')) {
    return next();
  }
  bcrypt.hash(this.password, salt, (err: Error, hash: string) => {
    if (err) return next(err);
    this.password = hash;
  });
});

UserSchema.methods.comparePasswords = function (
  candidatePassword: string,
  next: (err: Error | null, same: boolean | null) => void,
) {
  bcrypt.compare(candidatePassword, this.password, function (err, isMatch) {
    if (err) {
      return next(err, null);
    }
    next(null, isMatch);
  });
};

export interface IUser extends Document {
  email: string;
  name: string;
  password: string;
  comparePasswords(candidatePassword: string, next: (err: Error | null, same: boolean | null) => void): void;
}

package versions:

"mongoose": "^5.7.11"
"@types/mongoose": "^5.5.32"
"typescript": "^3.7.2"

Try to compare Password using mongoose and bcrypt in typescript

1 Answers1