middleware-patterns

Next.js middleware runs before every request and can protect routes by centralizing authentication checks. Define protected paths in your middleware matcher, implement an auth check against cookies, and redirect unauthenticated users to sign-in while preserving the original URL for post-login navigation.

Yes. Middleware can capture the full original URL before redirecting to sign-in, then pass it as a query parameter or state. After authentication succeeds, your app redirects users back to their intended destination instead of a default page.

Edge-runtime middleware must avoid non-edge APIs. Check authentication by reading cookies directly in middleware rather than calling external services or Node.js-only libraries. This keeps your auth logic fast and deployable to edge functions.

Use middleware with a pattern-based matcher to identify protected routes like `/dashboard`, `/league`, and `/admin`. Implement an auth check for each request to those paths and redirect unauthenticated visitors to your sign-in page.

Yes. Middleware can inject headers before requests reach your application. This is useful for passing auth context to layouts, enabling debugging, or signaling request metadata to your API routes and server components.

Middleware patterns handle route-level protection by checking auth state. For role-based or tenant-specific access control beyond route matching, combine middleware guards with component-level checks or API middleware that inspect user claims and permissions.