Login authentication is a crucial topic for every developer. Safely managing user data and protected pages while running a website is essential. So, how can this be achieved? The answer lies in using the `middleware.ts` file of Next.js.
In this article, we will explore how to handle login authentication using the `middleware.ts` file. By the end of this read, you’ll have a powerful tool to solve login authentication issues.
1. Why use `middleware.ts`?
`middleware.ts` is used in Next.js to handle specific requests or redirect user requests. It can serve more than just checking the login status. It is especially useful in scenarios like:
- Access control for protected pages: You can implement functionality that checks the login status before the user accesses a protected page, redirecting them to the login page if they are not logged in.
- Handling user authentication data: It allows you to verify user cookies or tokens and redirect the user to a desired page based on specific conditions.
import { NextResponse } from 'next/server';
import type { NextRequest } from 'next/server';
export function middleware(req: NextRequest) {
const token = req.cookies.get('jwt_token');
// Redirect to login page if token is missing
if (!token) {
return NextResponse.redirect(new URL('/login', req.url));
}
// Proceed with the request if token exists
return NextResponse.next();
}
export const config = {
matcher: ['/protected-page'], // Setting the path for protected pages
};
In the example code above, when a user tries to access a specific page, the login token is checked, and if no token is found, the user is automatically redirected to the login page. This method of handling user requests enhances security and improves user experience.
2. When might `middleware.ts` not be necessary?
On the other hand, `middleware.ts` is not essential for every project. In some cases, login authentication can be adequately handled without using middleware.
- Simple login authentication: If receiving a JWT token during login, storing it in `localStorage`, or setting it as an HTTP-only cookie to use in subsequent API requests is sufficient.
- Client-side routing: Implementing login checks directly within React components and redirecting as needed can be simpler and more straightforward.
Thus, while `middleware.ts` is a powerful tool, it may not always be necessary depending on the use case. Sometimes, checking the login state on the client side and handling it simply is more appropriate.
3. Conclusion: The pros and cons of using `middleware.ts`
Using `middleware.ts` can significantly enhance website security and user experience. However, it should only be employed when necessary, based on the project’s requirements. If used correctly, it can help you build a more robust website, offering better user experiences and strengthened data security.
Now, try incorporating `middleware.ts` into your project. Learning to use it appropriately based on the situation will be a great asset in building a more powerful website.