[5.x] Revert etags (#13933)

Author: jasonvarga

src/Http/Responses/DataResponse.php

@@ -42,12 +42,6 @@ public function toResponse($request)
             ->make($this->contents())
             ->withHeaders($this->headers);
 
-        if ($content = $response->getContent()) {
-            $response
-                ->setEtag(md5($content))
-                ->isNotModified($request);
-        }
-
         ResponseCreated::dispatch($response, $this->data);
 
         return $response;

src/StaticCaching/Middleware/Cache.php

@@ -50,15 +50,13 @@ public function __construct(Cacher $cacher, Session $nocache)
     public function handle($request, Closure $next)
     {
         if ($response = $this->attemptToServeCachedResponse($request)) {
-            return $this->addEtagToResponse($request, $response);
+            return $response;
         }
 
         $lock = $this->createLock($request);
 
         try {
-            return $lock->block($this->lockFor,
-                fn () => $this->addEtagToResponse($request, $this->handleRequest($request, $next))
-            );
+            return $lock->block($this->lockFor, fn () => $this->handleRequest($request, $next));
         } catch (LockTimeoutException $e) {
             return $this->outputRefreshResponse($request);
         }
@@ -231,24 +229,4 @@ private function outputRefreshResponse($request)
 
         return response($html, 503, ['Retry-After' => 1]);
     }
-
-    private function addEtagToResponse($request, $response)
-    {
-        if (! $response->isRedirect() && $content = $response->getContent()) {
-            // Clear any potentially stale cache-related headers that might interfere
-            $response->headers->remove('ETag');
-            $response->headers->remove('Last-Modified');
-
-            // Set fresh ETag based on current content
-            $response->setEtag(md5($content));
-
-            // Only call isNotModified() if request has cache validation headers
-            // This prevents 304 responses to clients that haven't sent If-None-Match or If-Modified-Since
-            if ($request->headers->has('If-None-Match') || $request->headers->has('If-Modified-Since')) {
-                $response->isNotModified($request);
-            }
-        }
-
-        return $response;
-    }
 }

tests/FrontendTest.php

@@ -1064,32 +1064,4 @@ public function it_protects_404_pages()
             ->get('/does-not-exist')
             ->assertStatus(404);
     }
-
-    #[Test]
-    public function it_sets_etag_header_and_returns_304_when_content_matches()
-    {
-        $this->withStandardBlueprints();
-        $this->withFakeViews();
-        $this->viewShouldReturnRaw('layout', '{{ template_content }}');
-        $this->viewShouldReturnRaw('default', '<h1>Test Page</h1>');
-
-        $this->createPage('about');
-
-        $response = $this->get('/about');
-        $response->assertStatus(200);
-
-        $content = trim($response->content());
-        $this->assertEquals('<h1>Test Page</h1>', $content);
-
-        $etag = $response->headers->get('ETag');
-        $this->assertEquals('"'.md5($content).'"', $etag); // Per spec, the quotes need to be in the string.
-
-        $response = $this->get('/about', ['If-None-Match' => $etag]);
-        $response->assertStatus(304);
-        $this->assertEmpty($response->content());
-
-        $response = $this->get('/about', ['If-None-Match' => '"wrong-etag"']);
-        $response->assertStatus(200);
-        $this->assertEquals('<h1>Test Page</h1>', trim($response->content()));
-    }
 }