[HttpFoundation] Add support for the 103 status code (Early Hints) and other 1XX statuses

Author: dunglas

CHANGELOG.md

@@ -17,6 +17,7 @@ CHANGELOG
  * Allow setting `debug.container.dump` to `false` to disable dumping the container to XML
  * Add `framework.http_cache.skip_response_headers` option
  * Display warmers duration on debug verbosity for `cache:clear` command
+ * Add `AbstractController::sendEarlyHints()` to send HTTP Early Hints
 
 6.2
 ---

Controller/AbstractController.php

@@ -12,6 +12,7 @@
 namespace Symfony\Bundle\FrameworkBundle\Controller;
 
 use Psr\Container\ContainerInterface;
+use Psr\Link\EvolvableLinkInterface;
 use Psr\Link\LinkInterface;
 use Symfony\Component\DependencyInjection\Exception\ServiceNotFoundException;
 use Symfony\Component\DependencyInjection\ParameterBag\ContainerBagInterface;
@@ -42,6 +43,7 @@
 use Symfony\Component\Serializer\SerializerInterface;
 use Symfony\Component\WebLink\EventListener\AddLinkHeaderListener;
 use Symfony\Component\WebLink\GenericLinkProvider;
+use Symfony\Component\WebLink\HttpHeaderSerializer;
 use Symfony\Contracts\Service\Attribute\Required;
 use Symfony\Contracts\Service\ServiceSubscriberInterface;
 use Twig\Environment;
@@ -92,6 +94,7 @@ public static function getSubscribedServices(): array
             'security.token_storage' => '?'.TokenStorageInterface::class,
             'security.csrf.token_manager' => '?'.CsrfTokenManagerInterface::class,
             'parameter_bag' => '?'.ContainerBagInterface::class,
+            'web_link.http_header_serializer' => '?'.HttpHeaderSerializer::class,
         ];
     }
 
@@ -402,4 +405,30 @@ protected function addLink(Request $request, LinkInterface $link): void
 
         $request->attributes->set('_links', $linkProvider->withLink($link));
     }
+
+    /**
+     * @param LinkInterface[] $links
+     */
+    protected function sendEarlyHints(iterable $links, Response $response = null): Response
+    {
+        if (!$this->container->has('web_link.http_header_serializer')) {
+            throw new \LogicException('You cannot use the "sendEarlyHints" method if the WebLink component is not available. Try running "composer require symfony/web-link".');
+        }
+
+        $response ??= new Response();
+
+        $populatedLinks = [];
+        foreach ($links as $link) {
+            if ($link instanceof EvolvableLinkInterface && !$link->getRels()) {
+                $link = $link->withRel('preload');
+            }
+
+            $populatedLinks[] = $link;
+        }
+
+        $response->headers->set('Link', $this->container->get('web_link.http_header_serializer')->serialize($populatedLinks), false);
+        $response->sendHeaders(103);
+
+        return $response;
+    }
 }

Resources/config/web_link.php

@@ -12,10 +12,18 @@
 namespace Symfony\Component\DependencyInjection\Loader\Configurator;
 
 use Symfony\Component\WebLink\EventListener\AddLinkHeaderListener;
+use Symfony\Component\WebLink\HttpHeaderSerializer;
 
 return static function (ContainerConfigurator $container) {
     $container->services()
+
+        ->set('web_link.http_header_serializer', HttpHeaderSerializer::class)
+        ->alias(HttpHeaderSerializer::class, 'web_link.http_header_serializer')
+
         ->set('web_link.add_link_header_listener', AddLinkHeaderListener::class)
+            ->args([
+                service('web_link.http_header_serializer'),
+            ])
             ->tag('kernel.event_subscriber')
     ;
 };

Tests/Controller/AbstractControllerTest.php

@@ -45,6 +45,7 @@
 use Symfony\Component\Security\Core\User\InMemoryUser;
 use Symfony\Component\Security\Csrf\CsrfTokenManagerInterface;
 use Symfony\Component\Serializer\SerializerInterface;
+use Symfony\Component\WebLink\HttpHeaderSerializer;
 use Symfony\Component\WebLink\Link;
 use Twig\Environment;
 
@@ -72,6 +73,7 @@ public function testSubscribedServices()
             'parameter_bag' => '?Symfony\\Component\\DependencyInjection\\ParameterBag\\ContainerBagInterface',
             'security.token_storage' => '?Symfony\\Component\\Security\\Core\\Authentication\\Token\\Storage\\TokenStorageInterface',
             'security.csrf.token_manager' => '?Symfony\\Component\\Security\\Csrf\\CsrfTokenManagerInterface',
+            'web_link.http_header_serializer' => '?Symfony\\Component\\WebLink\\HttpHeaderSerializer',
         ];
 
         $this->assertEquals($expectedServices, $subscribed, 'Subscribed core services in AbstractController have changed');
@@ -677,4 +679,20 @@ public function testAddLink()
         $this->assertContains($link1, $links);
         $this->assertContains($link2, $links);
     }
+
+    public function testSendEarlyHints()
+    {
+        $container = new Container();
+        $container->set('web_link.http_header_serializer', new HttpHeaderSerializer());
+
+        $controller = $this->createController();
+        $controller->setContainer($container);
+
+        $response = $controller->sendEarlyHints([
+            (new Link(href: '/style.css'))->withAttribute('as', 'stylesheet'),
+            (new Link(href: '/script.js'))->withAttribute('as', 'script'),
+        ]);
+
+        $this->assertSame('</style.css>; rel="preload"; as="stylesheet",</script.js>; rel="preload"; as="script"', $response->headers->get('Link'));
+    }
 }

composer.json

@@ -25,7 +25,7 @@
         "symfony/deprecation-contracts": "^2.5|^3",
         "symfony/error-handler": "^6.1",
         "symfony/event-dispatcher": "^5.4|^6.0",
-        "symfony/http-foundation": "^6.2",
+        "symfony/http-foundation": "^6.3",
         "symfony/http-kernel": "^6.3",
         "symfony/polyfill-mbstring": "~1.0",
         "symfony/filesystem": "^5.4|^6.0",