Compass app (#2446)

compass_app/server/lib/middleware/auth.dart

@@ -0,0 +1,30 @@
+// Copyright 2024 The Flutter team. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:shelf/shelf.dart';
+
+import '../config/constants.dart';
+
+/// Implements a simple auth Middleware.
+///
+/// This is provided as an example for Flutter architectural purposes only
+/// and shouldn't be used as example on how to implement authentication
+/// in production.
+///
+/// This Middleware checks if the token is present in the request headers,
+/// otherwise returns a 401 Unauthorized response.
+///
+/// This token does not expire and is not secure.
+Middleware authRequests() => (innerHandler) {
+      return (Request request) async {
+        if (request.url.path != 'login' &&
+            request.headers['Authorization'] != 'Bearer ${Constants.token}') {
+          // If the request is not a login request and the token is not present,
+          // return a 401 Unauthorized response.
+          return Response.unauthorized('Unauthorized');
+        }
+
+        return innerHandler(request);
+      };
+    };