How do you handle catch-all routes in Next.js?

Catch-All Routes in Next.js allow dynamic URL matching with flexible path parameters, empowering your app’s routing system.

Key Features

• Dynamic Parameters: Access route wildcard segments through the … rest parameter.
• Matching Order: Definition order determines the route precedence.
• Fallback behavior: Optionally configure fallback settings.

Configuration

Next.js routing file (pages/foo/[…bar].js):

• Root Catch-All: Load for any unmatched path or /foo route without further subpaths.

export default function CatchAll() {
  // Logic for Root Catch-All
}

• Nested Catch-Alls: Triggered when the root path is accessed along with subdirectories.

export default function NestedCatchAll() {
  // Logic for Nested Catch-All
}

• Fallback Pages: Ideal for error handling or awaiting dynamic data.

export async function getServerSideProps() {
  // Data-fetching logic
  return { props: { data } };
}

export default function Fallback({ data }) {
  return <div>{data}</div>;
}

Fallback Modes

Specify fallback behavior in the getStaticPaths method:

• True: Generates paths at build time and handles missing routes as fallbacks (SSG-only).
• False: Precisely predefines page paths during build (no fallback).
• ‘blocking’: Handles fallbacks via server at run-time (SSR or SSG).