User model file for Udemy Node Course

user.js

const mongoose = require('mongoose');
const validator = require('validator');
const bcrypt = require('bcryptjs');
const jwt = require('jsonwebtoken');

const userSchema = new mongoose.Schema({
    name: { 
        type: String,
        required: true,
        trim: true
    },
    email: {
        type: String,
        unique: true, // Email can only be used once
        required: true,
        trim: true,
        lowercase: true,
        validate(value) {
            if (!validator.isEmail(value))
                throw new Error('Email is invalid');
        }
    },
    age: { 
        type: Number,
        default: 0,
        validate(value) {
            if (value < 0) {
                throw new Error('Age must be a positive number');
            }
        }
    },
    password: {
        type: String,
        required: true,
        minlength: 7,
        trim: true,
        validate(value) {
            if (value.toLowerCase().includes('password'))
                throw new Error('Your password cannot include the word "password" in any form')
        }
    },
    tokens: [{
        token: {
            type: String,
            required: true
        }
    }]
});

// Methods available on instances
userSchema.methods.generateAuthToken = async function() {
    const user = this;
    const token = jwt.sign({ _id: user._id.toString() }, 'thisismykey');
    user.tokens = user.tokens.concat({ token });
    await user.save();
    return token;
};

// Statics available on model
userSchema.statics.findByCredentials = async function(email, password) {
    const user = await this.findOne({ email });

    if (!user)
        throw new Error('Unable to login');

    const isMatch = await bcrypt.compare(password, user.password);
    if (!isMatch)
        throw new Error('Unable to login');

    return user;
};

// Hash the plain text password before saving
userSchema.pre('save', async function(next) {
    const user = this;

    if (user.isModified('password'))
        user.password = await bcrypt.hash(user.password, 8);

    console.log('Just before saving');

    next();
});

module.exports = mongoose.model('User', userSchema);