Next.js Middleware & Auth
Middleware, NextAuth.js, JWT, session management, protected routes, RBAC
1What is middleware in Next.js?
What is middleware in Next.js?
Answer
Next.js middleware is code that runs before a request is processed, allowing you to modify the response, redirect, add headers, or block access. It runs on the Edge Runtime for optimal performance. Typically used for authentication, geolocation, or logging.
2Where to place the middleware file in a Next.js project with App Router?
Where to place the middleware file in a Next.js project with App Router?
Answer
The middleware.ts (or .js) file must be placed at the project root, at the same level as the app folder. Next.js automatically detects this file and executes it for all routes. Alternatively, it can be placed in the src folder if the project uses this structure.
3How to define the routes on which middleware executes?
How to define the routes on which middleware executes?
Answer
Using the matcher configuration in middleware allows specifying concerned routes via path patterns. By default, middleware executes on all routes except static files. The matcher supports wildcards and regex for precise control of targeted routes.
What is the main advantage of using NextAuth.js for authentication?
How to protect a route with Next.js middleware?
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