feature #217 [Turbo] Simplify stream negotiation (dunglas)

This PR was squashed before being merged into the 2.x branch.

Discussion
----------

[Turbo] Simplify stream negotiation

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes <!-- please update src/**/CHANGELOG.md files -->
| Tickets       | n/a
| License       | MIT

This patch replaces the ad-hoc content negotiation system for Turbo Streams used by the bundle. HttpFoundation's native content negotiation features are now used instead. This greatly simplifies the code, which is security-sensitive, and improves DX (content negotiation is now consistent with how it is handled in the rest of the framework).

Replaces #214. Needs #215 and symfony/symfony#44980.

Commits
-------

b6de1e3 [Turbo] Simplify stream negotiation

Author: chalasr

src/Turbo/CHANGELOG.md

@@ -1,5 +1,29 @@
 # CHANGELOG
 
+## 2.1
+
+-   `TurboStreamResponse` and `AddTurboStreamFormatSubscriber` have been removed, use native content negotiation instead:
+
+    ```php
+    use Symfony\UX\Turbo\TurboBundle;
+
+    class TaskController extends AbstractController
+    {
+        public function new(Request $request): Response
+        {
+            // ...
+            if (TurboBundle::STREAM_FORMAT === $request->getPreferredFormat()) {
+                $request->setRequestFormat(TurboBundle::STREAM_FORMAT);
+                $response = $this->render('task/success.stream.html.twig', ['task' => $task]);
+            } else {
+                $response = $this->render('task/success.html.twig', ['task' => $task]);
+            }
+
+            return $response->setVary('Accept');
+        }
+    }
+    ```
+
 ## 2.0
 
 -   Support for `stimulus` version 2 was removed and support for `@hotwired/stimulus`

src/Turbo/README.md

@@ -295,7 +295,7 @@ namespace App\Controller;
 use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
-use Symfony\UX\Turbo\Stream\TurboStreamResponse;
+use Symfony\UX\Turbo\TurboBundle;
 use App\Entity\Task;
 
 class TaskController extends AbstractController
@@ -311,9 +311,10 @@ class TaskController extends AbstractController
             // ... perform some action, such as saving the task to the database
 
             // 🔥 The magic happens here! 🔥
-            if (TurboStreamResponse::STREAM_FORMAT === $request->getPreferredFormat()) {
-                // If the request comes from Turbo, only send the HTML to update using a TurboStreamResponse
-                return $this->render('task/success.stream.html.twig', ['task' => $task], new TurboStreamResponse());
+            if (TurboBundle::STREAM_FORMAT === $request->getPreferredFormat()) {
+                // If the request comes from Turbo, set the content type as text/vnd.turbo-stream.html and only send the HTML to update
+                $request->setFormat(TurboBundle::STREAM_FORMAT);
+                return $this->render('task/success.stream.html.twig', ['task' => $task]);
             }
 
             // If the client doesn't support JavaScript, or isn't using Turbo, the form still works as usual.

src/Turbo/Resources/config/services.php

@@ -16,7 +16,6 @@
 use Symfony\UX\Turbo\Broadcaster\ImuxBroadcaster;
 use Symfony\UX\Turbo\Broadcaster\TwigBroadcaster;
 use Symfony\UX\Turbo\Doctrine\BroadcastListener;
-use Symfony\UX\Turbo\Stream\AddTurboStreamFormatSubscriber;
 use Symfony\UX\Turbo\Twig\TwigExtension;
 
 /*
@@ -25,9 +24,6 @@
 return static function (ContainerConfigurator $container): void {
     $container->services()
 
-        ->set('turbo.kernel.event_subscriber', AddTurboStreamFormatSubscriber::class)
-            ->tag('kernel.event_subscriber')
-
         ->set('turbo.broadcaster.imux', ImuxBroadcaster::class)
             ->args([tagged_iterator('turbo.broadcaster')])
 

src/Turbo/Stream/AddTurboStreamFormatSubscriber.php

@@ -34,7 +34,6 @@
 use Symfony\Component\Mercure\HubInterface;
 use Symfony\Component\Mercure\Update;
 use Symfony\Component\Routing\Loader\Configurator\RoutingConfigurator;
-use Symfony\UX\Turbo\Stream\TurboStreamResponse;
 use Symfony\UX\Turbo\TurboBundle;
 use Symfony\WebpackEncoreBundle\WebpackEncoreBundle;
 use Twig\Environment;
@@ -131,11 +130,14 @@ public function getProjectDir(): string
 
     public function form(Request $request, Environment $twig): Response
     {
-        if (TurboStreamResponse::STREAM_FORMAT === $request->getPreferredFormat()) {
-            return new TurboStreamResponse($twig->render('form.stream.html.twig'));
+        if (TurboBundle::STREAM_FORMAT === $request->getPreferredFormat()) {
+            $request->setRequestFormat(TurboBundle::STREAM_FORMAT);
+            $response = (new Response($twig->render('form.stream.html.twig')));
+        } else {
+            $response = new Response('Turbo not installed, default to plain HTML.');
         }
 
-        return new Response('Turbo not installed, default to plain HTML.');
+        return $response->setVary('Accept');
     }
 
     public function chat(Request $request, FormFactoryInterface $formFactory, HubInterface $mercureHub, Environment $twig): Response

src/Turbo/Stream/TurboStreamResponse.php

@@ -14,6 +14,7 @@
 use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
 use Symfony\Component\DependencyInjection\Compiler\PassConfig;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpKernel\Bundle\Bundle;
 
 /**
@@ -23,6 +24,14 @@
  */
 final class TurboBundle extends Bundle
 {
+    public const STREAM_FORMAT = 'turbo_stream';
+    public const STREAM_MEDIA_TYPE = 'text/vnd.turbo-stream.html';
+
+    public function boot(): void
+    {
+        (new Request())->setFormat(self::STREAM_FORMAT, self::STREAM_MEDIA_TYPE);
+    }
+
     public function build(ContainerBuilder $container): void
     {
         parent::build($container);