authentication.js

const passport = require('passport');
const localStrategy = require('passport-local').Strategy;
const JWTstrategy = require('passport-jwt').Strategy;
const ExtractJWT = require('passport-jwt').ExtractJwt;

const { User } = require('../models/');

//This verifies that the token sent by the user is valid
passport.use(new JWTstrategy({
  //secret we used to sign our JWT
  secretOrKey: process.env.JWT_SECRET,
  //we expect the user to send the token as a query parameter with the name 'secret_token'
  jwtFromRequest: ExtractJWT.fromAuthHeaderAsBearerToken(),
}, async (token, done) => {
  try {
    //Pass the user details to the next middleware
    const user = await User.findOne({ where: { email: token.user.email }})
    return done(null, user);
  } catch (error) {
    done(error);
  }
}));

//Create a passport middleware to handle user registration
passport.use('signup', new localStrategy({
  usernameField: 'email',
  passwordField: 'password'
}, async (email, password, done) => {
  try {
    //Save the information provided by the user to the the database
    const user = await User.create({
      email,
      password
    });
    //Send the user information to the next middleware
    return done(null, user);
  } catch (error) {
    done(error);
  }
}));

//Create a passport middleware to handle User login
passport.use('login', new localStrategy({
  usernameField: 'email',
  passwordField: 'password'
}, async (email, password, done) => {
  try {
    //Find the user associated with the email provided by the user
    const user = await User.findOne({ where: { email } });
    if (!user) {
      //If the user isn't found in the database, return a message
      return done(null, false, { message: 'User not found' });
    }
    //Validate password and make sure it matches with the corresponding hash stored in the database
    //If the passwords match, it returns a value of true.
    const validate = await user.isValidPassword(password);
    if (!validate) {
      return done(null, false, { message: 'Wrong Password' });
    }
    //Send the user information to the next middleware
    return done(null, user, { message: 'Logged in Successfully' });
  } catch (error) {
    return done(error);
  }
}));