Laravel Version

12.39.0

PHP Version

8.4.14

Database Driver & Version

No response

Description

Request::wantsJson uses Symfony's getAcceptableContentTypes internally which caches the headers so this doesn't work in a middleware:

if ($request->acceptsAnyContentType()) {
    $request->headers->set('Accept', 'application/json');
}

if (!$request->wantsJson()) {
    return response()->json(['message' => 'Not Acceptable.'], 406);
}

return $next($request);

There is also no way to trigger a reset of acceptableContentTypes.

Steps To Reproduce

Have the following code in a middleware:

if ($request->acceptsAnyContentType()) {
    $request->headers->set('Accept', 'application/json');
}

dd($request->wantsJson());

Call an endpoint with Accept set to */*.