Welcome to the next step in building your full-featured To-Do list application! Now that you have learned how to implement user authentication, it's important to ensure that only authenticated users access certain parts of your application. In this unit, we will explore how to protect routes using middleware in Django.

In this section, you'll learn how to implement middleware to secure your application routes. We'll go through the following key points:

1. Understanding Middleware: Middleware acts as a bridge between a web server and a web application. It processes requests before they reach the view and can also alter responses before they get sent to the client.

2. Creating and Using Middleware: You’ll learn how to create custom middleware to check for user authentication. Here’s an example:

   Let's break down the code:

   • The AuthMiddleware class checks if the current route is in the unprotected_routes list. If it is, the middleware allows the request to proceed. This is useful for routes like login, register, and logout, which should be accessible to all users regardless of authentication status. Notice, that we use the resolve function to get the current route name.
   • If the route is not in the unprotected_routes list, the middleware checks if the request has a valid header. If not, it returns a response. Notice that the token is hardcoded here for demonstration purposes. In a real-world scenario, you would validate the token against a database.

Middleware is essential because it:

• Adds an Extra Layer of Security: Middleware checks each request before it reaches the view, ensuring that only authorized users can access restricted parts of your application.
• Centralizes Control: Instead of adding checks in every view, you can handle access control in one place, making your code cleaner and easier to maintain.
• Enhances User Experience: By ensuring that users are appropriately authenticated, you provide a smoother and more secure application experience, preventing unauthorized access seamlessly.

Securing your application with middleware not only protects sensitive data but also adds professionalism and reliability to your application. Ready to get started with practice? Let's dive in!