nextjs-15

Next.js App Router file structure conventions dictate organizing layouts, pages, loading, and error files hierarchically. Separating private components into dedicated folders ensures predictable routing and prevents architectural mistakes during project implementation.

Creating a server action in Next.js involves defining an async function to process form mutations like user creation. You must implement revalidation to refresh data caches and use redirects to navigate users after the server action successfully completes.

Protecting a dashboard route with middleware in Next.js requires configuring a matcher to target specific paths. You write logic inside the middleware function to check authentication and redirect unauthorized users away from protected routes.

Fetching data and streaming UI in Next.js server components uses async functions for parallel data fetching. Wrapping dynamic page sections with React Suspense enables streaming, allowing the UI to render progressively as data resolves.

You can generate dynamic metadata for pages using the Next.js App Router by exporting a generateMetadata function. This function accesses route parameters to dynamically produce page titles and descriptions for SEO purposes.

Next.js App Router fully supports API route handlers alongside server actions. Route handlers provide templates for building REST endpoints within the App Router, offering an alternative to server actions for handling external API requests.