Bcrypt password fails when i try to compare?

Question

I am a complete beginner in coding, currently learning NodeJs and i am stuck with this situation for days now. I am trying to compare the hashed password in my mongodb with the users input through postman. I am using bcrypt to compare the hashed password with the original string but i am getting false statement. Any help is much appreciated

This is the mongoose model Schema,

const usersSchema = new mongoose.Schema({
  name: {
    type: String,
    required: true,
    trim: true,
  },
  email: {
    type: String,
    unique: true,
    required: true,
    lowercase: true,
    validate(value) {
      if (!validator.isEmail(value)) throw new Error("Invalid email");
    },
  },
  password: {
    type: String,
    required: true,
    trim: true,
    minLength: 7,
    validate(value) {
      if (value.toLowerCase().includes("password")) {
        throw new Error("Password should not consist of string 'password'.");
      }
    },
  },
})

Right here I hash the password before saving to the database;

usersSchema.pre("save", async function (next) {

  const user = this;
  const saltRounds = 8;

  if (user.isModified("password")) {
    user.password = await bcrypt.hash(user.password, saltRounds);
  }

  next();
});

Below is the login route;

router.post("/users/login", async (req, res) => {
  try {
    const user = await Users.findByCredentials(
      req.body.email,
      req.body.password
    );

    res.send(user);
  } catch (error) {
    res.status(400).send(error);
  }
});

Below is where I try to compare the passwords, help me figure out why I am getting false.

usersSchema.statics.findByCredentials = async (email, password) => {
  const user = await Users.findOne({ email: email });

  if (!user) {
    throw new Error("Unable to log in!");
  }

  const isMatch = await bcrypt.compare(password, user.password);

  if (!isMatch) {
    throw new Error("Unable to login");
  }

  return user;
};

Answer 1

when ever you use bcrypt it works with you password property on your model In this case you dont want to trim or lower case any properties of password. So when designing Schema we dont want to over-load password with extra validations.We have to work with minimal validations in order for bcrypt to function properly.I had the same issue i removedlowerCase:true,trim:true from the Schema then it worked. try to remove extra validations or restriction from password other wise it will interfere with bcrypt compare function.

Answer 2

try using bcryptjs.hashSync() and bcryptjs.compareSync instead