What are some examples of middleware in Next.js?

What are some examples of middleware in Next.js?

Next.js middleware allows you to run code before a request is completed. For example, you can use middleware for authentication, logging, or modifying requests.

Can you give me a specific example of authentication middleware?

Sure! You can create a middleware that checks if a user is authenticated by verifying a token in the request headers. If the token is valid, the request proceeds; otherwise, it redirects to a login page.

How do I implement this in my Next.js app?

You can create a middleware file in the pages/api directory and use the NextResponse object to handle the request and response. Here's a simple example:

import { NextResponse } from 'next/server';

export function middleware(req) {
  const token = req.headers.get('Authorization');
  if (!token) {
    return NextResponse.redirect('/login');
  }
  return NextResponse.next();
}

What other types of middleware can I use?

You can use middleware for logging requests, handling CORS, rate limiting, or even modifying response headers. The possibilities are quite extensive!