From b4772e53998e56c15eb1af7848161c39d61fb7bd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dani=C3=ABl=20Klabbers?= <luceos@users.noreply.github.com>
Date: Fri, 8 Oct 2021 00:34:22 +0200
Subject: [PATCH] [huntr] adding cache control headers to the admin area
 (#3097)

This PR forces the `Cache-Control: no-store, max-age=0` header to the response in the Admin Area. This forces cache to be ignored upon browsing back and forth between pages using the browser controls. Although absolutely no fail safe, it should provide better protection against serving cached pages once an admin has signed out.
---
 src/Admin/AdminServiceProvider.php           |  3 ++-
 src/Admin/Middleware/DisableBrowserCache.php | 25 ++++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 src/Admin/Middleware/DisableBrowserCache.php

diff --git a/src/Admin/AdminServiceProvider.php b/src/Admin/AdminServiceProvider.php
index f07da123b..c5563aace 100644
--- a/src/Admin/AdminServiceProvider.php
+++ b/src/Admin/AdminServiceProvider.php
@@ -61,7 +61,8 @@ class AdminServiceProvider extends AbstractServiceProvider
                 HttpMiddleware\CheckCsrfToken::class,
                 Middleware\RequireAdministrateAbility::class,
                 HttpMiddleware\ReferrerPolicyHeader::class,
-                HttpMiddleware\ContentTypeOptionsHeader::class
+                HttpMiddleware\ContentTypeOptionsHeader::class,
+                Middleware\DisableBrowserCache::class,
             ];
         });
 
diff --git a/src/Admin/Middleware/DisableBrowserCache.php b/src/Admin/Middleware/DisableBrowserCache.php
new file mode 100644
index 000000000..731ea8157
--- /dev/null
+++ b/src/Admin/Middleware/DisableBrowserCache.php
@@ -0,0 +1,25 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * For detailed copyright and license information, please view the
+ * LICENSE file that was distributed with this source code.
+ */
+
+namespace Flarum\Admin\Middleware;
+
+use Psr\Http\Message\ResponseInterface as Response;
+use Psr\Http\Message\ServerRequestInterface as Request;
+use Psr\Http\Server\MiddlewareInterface as Middleware;
+use Psr\Http\Server\RequestHandlerInterface as Handler;
+
+class DisableBrowserCache implements Middleware
+{
+    public function process(Request $request, Handler $handler): Response
+    {
+        $response = $handler->handle($request);
+
+        return $response->withHeader('Cache-Control', 'max-age=0, no-store');
+    }
+}