setup-mern/templates/src/middleware/authMiddleware.js

A CLI tool to generate a MERN backend boilerplate in seconds!

const jwt = require('jsonwebtoken');
const User = require('../models/User');
const { JWT_SECRET } = require('../config/envConfig');

exports.protect = async (req, res, next) => {
  try {
    let token;
    if (req.headers.authorization && req.headers.authorization.startsWith('Bearer')) {
      token = req.headers.authorization.split(' ')[1];
    }

    if (!token) {
      throw new Error('You are not logged in! Please log in to get access.');
    }

    const decoded = jwt.verify(token, JWT_SECRET);
    const user = await User.findById(decoded.id);

    if (!user) {
      throw new Error('The user belonging to this token no longer exists.');
    }

    req.user = user;
    next();
  } catch (err) {
    res.status(401).json({ status: 'error', message: err.message });
  }
};