Introduction to Authentication with Auth0

Authentication is a crucial aspect of any web application, and Next.js provides a robust framework for implementing authentication using various providers, including Auth0.

Step 1: Create a New Next.js Project

To start, create a new Next.js project using npx create-next-app my-auth.

npx create-next-app my-auth
cd my-auth

Step 2: Install Required Dependencies

Install the required dependencies, including @auth0/auth0-js.

npm install @auth0/auth0-js

Step 3: Configure Auth0

Configure Auth0 by creating a new Auth0 account and setting up a new application.

// pages/api/auth.js
import { handleAuth } from '@auth0/auth0-js';

const domain = 'your-auth0-domain.com';
const clientId = 'your-client-id';
const audience = 'https://your-auth0-domain.com/api/v2/';
const scope = 'openid profile email';

const handleLogin = async (req, res) => {
  try {
    const { state, code } = req.query;
    const token = await handleAuth(code, clientId, domain, audience, scope);
    res.json(token);
  } catch (error) {
    console.error(error);
    res.status(500).json({ message: 'Error logging in' });
  }
};

export default handleLogin;

Step 4: Implement Login and Logout

Implement login and logout functionality using the Auth0 API.

// pages/index.js
import { useState, useEffect } from 'react';
import { login, logout } from '../api/auth';

const Home = () => {
  const [user, setUser] = useState(null);

const handleLogin = async () => {
    const token = await login();
    setUser(token);
  };

const handleLogout = async () => {
    await logout();
    setUser(null);
  };

return (
    <div>
      {user ? (
        <button onClick={handleLogout}>Logout</button>
      ) : (
        <button onClick={handleLogin}>Login</button>
      )}
    </div>
  );
};

export default Home;

Conclusion

In this tutorial, you learned how to implement authentication in a Next.js application using Auth0.