update middleware order

Signed-off-by: Stephen Glass <stephen@stephen.glass>

packages/core-app-api/src/apis/implementations/AuthErrorApi/SignInAuthErrorApi.ts

@@ -1,5 +1,5 @@
 /*
- * Copyright 2021 The Backstage Authors
+ * Copyright 2024 The Backstage Authors
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.

plugins/auth-backend/src/service/router.ts

@@ -170,16 +170,13 @@ export async function createRouter(
     userInfoDatabaseHandler,
   });
 
+  router.use(createCookieAuthErrorMiddleware(appUrl, authUrl));
+
   // Gives a more helpful error message than a plain 404
-  router.use('/:provider/', (req, _, next) => {
+  router.use('/:provider/', req => {
     const { provider } = req.params;
-    if (provider.startsWith('.backstage')) {
-      return next('route');
-    }
     throw new NotFoundError(`Unknown auth provider '${provider}'`);
   });
 
-  router.use(createCookieAuthErrorMiddleware(appUrl, authUrl));
-
   return router;
 }