til/nextjs/match-middleware-on-groups-of-paths.md

Match Middleware On Groups Of Paths

The Next.js middleware takes an array of path matchers in its config to decide what pages to apply middleware to. These paths can use regex via path-to-regexp.

Let's say I'm using middleware to do authentication checks for certain pages.

If I want to visits to my /dashboard page to run through middleware, I can configure my matcher like so:

export const config = { matcher: ["/dashboard"] };

If we want to match against /dashboard and any possible sub-structure to that path, we can apply some regex:

export const config = { matcher: ["/dashboard/:all*"] };

That will match /dashboard, /dashboard/hello, dashboard/hello/world, etc.

Lastly, let's say I only want to match routes under the /dashboard route. I can replace the * (zero-or-more matches) with a + (one-or-more matches):

export const config = { matcher: ["/dashboard/:all+"] };

That will match /dashboard/hello, /dashboard/hello/world, etc., but not /dashboard.

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