feature #47916 [Routing] PSR-4 directory loader (derrabus)

This PR was merged into the 6.2 branch.

Discussion
----------

[Routing] PSR-4 directory loader

| Q             | A
| ------------- | ---
| Branch?       | 6.2
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no (but we could…)
| Tickets       | Fix #47881
| License       | MIT
| Doc PR        | symfony/symfony-docs#17373

This PR adds a PSR-4 directory loader to the Routing component.

When we currently want to load routes from a directory with controllers, we configure it like this:

```YAML
controllers:
    resource: ../src/Controller/
    type: attribute
```

What happens now is that `AnnotationDirectoryLoader` searches that directory recursively for `*.php` files and uses PHP's tokenizer extension to discover all controller classes that are defined within that directory. This step feels unnecessarily expensive given that modern projects follow the PSR-4 standard to structure their code. And if we use the DI component's autodiscovery feature to register our controllers as services, our controller directory already has to follow PSR-4.

A client I'm working with adds the additional challange that they deliver their code to their customers in encrypted form (using SourceGuardian). This means that the PHP files contain encrypted bytecode instead of plain PHP and thus cannot be parsed. We currently overcome this limitation by extending `AnnotationDirectoryLoader` and overriding the protected `findClass()` method.

This PR proposes to extend the resource type `attribute` and allow to suffix it with a PSR-4 namespace root.

```YAML
controllers:
    resource: ../src/Controller/
    type: attribute@App\Controller
```

In order to use PSR-4 to discover controller classes, the directory path is not enough. We always need an additional piece of information which is the namespace root for the given directory. Without changing large parts of the Config component, I did not find a nice way to pass down that information to the PSR-4 route loader. Encoding that information into the `type` parameter seemed like the pragmatic approach, but I'm open to discussing alternatives.

This approach should play nicely with projects that already use attributes for routing and PSR-4 autodiscovery to register controllers as services. In fact, most project should be able to swap the `type: annotation` or `type: attribute` config with `type: attribute@Your\Namespace\Here` and the only difference they notice is that router compilation becomes a bit faster.

Commits
-------

158e30df9a [Routing] PSR-4 directory loader

Author: fabpot

DependencyInjection/FrameworkExtension.php

@@ -25,7 +25,6 @@
 use Symfony\Bridge\Monolog\Processor\DebugProcessor;
 use Symfony\Bridge\Twig\Extension\CsrfExtension;
 use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
-use Symfony\Bundle\FrameworkBundle\Routing\AnnotatedRouteControllerLoader;
 use Symfony\Bundle\FrameworkBundle\Routing\RouteLoaderInterface;
 use Symfony\Bundle\FullStack;
 use Symfony\Bundle\MercureBundle\MercureBundle;
@@ -194,8 +193,7 @@
 use Symfony\Component\RateLimiter\LimiterInterface;
 use Symfony\Component\RateLimiter\RateLimiterFactory;
 use Symfony\Component\RateLimiter\Storage\CacheStorage;
-use Symfony\Component\Routing\Loader\AnnotationDirectoryLoader;
-use Symfony\Component\Routing\Loader\AnnotationFileLoader;
+use Symfony\Component\Routing\Loader\Psr4DirectoryLoader;
 use Symfony\Component\Security\Core\AuthenticationEvents;
 use Symfony\Component\Security\Core\Exception\AuthenticationException;
 use Symfony\Component\Security\Csrf\CsrfTokenManagerInterface;
@@ -1157,29 +1155,9 @@ private function registerRouterConfiguration(array $config, ContainerBuilder $co
                 ->replaceArgument(0, $config['default_uri']);
         }
 
-        $container->register('routing.loader.annotation', AnnotatedRouteControllerLoader::class)
-            ->setPublic(false)
-            ->addTag('routing.loader', ['priority' => -10])
-            ->setArguments([
-                new Reference('annotation_reader', ContainerInterface::NULL_ON_INVALID_REFERENCE),
-                '%kernel.environment%',
-            ]);
-
-        $container->register('routing.loader.annotation.directory', AnnotationDirectoryLoader::class)
-            ->setPublic(false)
-            ->addTag('routing.loader', ['priority' => -10])
-            ->setArguments([
-                new Reference('file_locator'),
-                new Reference('routing.loader.annotation'),
-            ]);
-
-        $container->register('routing.loader.annotation.file', AnnotationFileLoader::class)
-            ->setPublic(false)
-            ->addTag('routing.loader', ['priority' => -10])
-            ->setArguments([
-                new Reference('file_locator'),
-                new Reference('routing.loader.annotation'),
-            ]);
+        if (!class_exists(Psr4DirectoryLoader::class)) {
+            $container->removeDefinition('routing.loader.psr4');
+        }
     }
 
     private function registerSessionConfiguration(array $config, ContainerBuilder $container, PhpFileLoader $loader)

Resources/config/routing.php

@@ -15,6 +15,7 @@
 use Symfony\Bundle\FrameworkBundle\CacheWarmer\RouterCacheWarmer;
 use Symfony\Bundle\FrameworkBundle\Controller\RedirectController;
 use Symfony\Bundle\FrameworkBundle\Controller\TemplateController;
+use Symfony\Bundle\FrameworkBundle\Routing\AnnotatedRouteControllerLoader;
 use Symfony\Bundle\FrameworkBundle\Routing\DelegatingLoader;
 use Symfony\Bundle\FrameworkBundle\Routing\RedirectableCompiledUrlMatcher;
 use Symfony\Bundle\FrameworkBundle\Routing\Router;
@@ -23,10 +24,13 @@
 use Symfony\Component\Routing\Generator\CompiledUrlGenerator;
 use Symfony\Component\Routing\Generator\Dumper\CompiledUrlGeneratorDumper;
 use Symfony\Component\Routing\Generator\UrlGeneratorInterface;
+use Symfony\Component\Routing\Loader\AnnotationDirectoryLoader;
+use Symfony\Component\Routing\Loader\AnnotationFileLoader;
 use Symfony\Component\Routing\Loader\ContainerLoader;
 use Symfony\Component\Routing\Loader\DirectoryLoader;
 use Symfony\Component\Routing\Loader\GlobFileLoader;
 use Symfony\Component\Routing\Loader\PhpFileLoader;
+use Symfony\Component\Routing\Loader\Psr4DirectoryLoader;
 use Symfony\Component\Routing\Loader\XmlFileLoader;
 use Symfony\Component\Routing\Loader\YamlFileLoader;
 use Symfony\Component\Routing\Matcher\Dumper\CompiledUrlMatcherDumper;
@@ -88,6 +92,33 @@
             ])
             ->tag('routing.loader')
 
+        ->set('routing.loader.annotation', AnnotatedRouteControllerLoader::class)
+            ->args([
+                service('annotation_reader')->nullOnInvalid(),
+                '%kernel.environment%',
+            ])
+            ->tag('routing.loader', ['priority' => -10])
+
+        ->set('routing.loader.annotation.directory', AnnotationDirectoryLoader::class)
+            ->args([
+                service('file_locator'),
+                service('routing.loader.annotation'),
+            ])
+            ->tag('routing.loader', ['priority' => -10])
+
+        ->set('routing.loader.annotation.file', AnnotationFileLoader::class)
+            ->args([
+                service('file_locator'),
+                service('routing.loader.annotation'),
+            ])
+            ->tag('routing.loader', ['priority' => -10])
+
+        ->set('routing.loader.psr4', Psr4DirectoryLoader::class)
+            ->args([
+                service('file_locator'),
+            ])
+            ->tag('routing.loader', ['priority' => -10])
+
         ->set('routing.loader', DelegatingLoader::class)
             ->public()
             ->args([

Tests/Functional/AbstractAttributeRoutingTest.php

@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Tests\Functional;
+
+abstract class AbstractAttributeRoutingTest extends AbstractWebTestCase
+{
+    /**
+     * @dataProvider getRoutes
+     */
+    public function testAnnotatedController(string $path, string $expectedValue)
+    {
+        $client = $this->createClient(['test_case' => $this->getTestCaseApp(), 'root_config' => 'config.yml']);
+        $client->request('GET', '/annotated'.$path);
+
+        $this->assertSame(200, $client->getResponse()->getStatusCode());
+        $this->assertSame($expectedValue, $client->getResponse()->getContent());
+
+        $router = self::getContainer()->get('router');
+
+        $this->assertSame('/annotated/create-transaction', $router->generate('symfony_framework_tests_functional_test_annotated_createtransaction'));
+    }
+
+    public function getRoutes(): array
+    {
+        return [
+            ['/null_request', 'Symfony\Component\HttpFoundation\Request'],
+            ['/null_argument', ''],
+            ['/null_argument_with_route_param', ''],
+            ['/null_argument_with_route_param/value', 'value'],
+            ['/argument_with_route_param_and_default', 'value'],
+            ['/argument_with_route_param_and_default/custom', 'custom'],
+        ];
+    }
+
+    abstract protected function getTestCaseApp(): string;
+}

Tests/Functional/AnnotatedControllerTest.php

@@ -11,33 +11,10 @@
 
 namespace Symfony\Bundle\FrameworkBundle\Tests\Functional;
 
-class AnnotatedControllerTest extends AbstractWebTestCase
+class AnnotatedControllerTest extends AbstractAttributeRoutingTest
 {
-    /**
-     * @dataProvider getRoutes
-     */
-    public function testAnnotatedController($path, $expectedValue)
+    protected function getTestCaseApp(): string
     {
-        $client = $this->createClient(['test_case' => 'AnnotatedController', 'root_config' => 'config.yml']);
-        $client->request('GET', '/annotated'.$path);
-
-        $this->assertSame(200, $client->getResponse()->getStatusCode());
-        $this->assertSame($expectedValue, $client->getResponse()->getContent());
-
-        $router = self::getContainer()->get('router');
-
-        $this->assertSame('/annotated/create-transaction', $router->generate('symfony_framework_tests_functional_test_annotated_createtransaction'));
-    }
-
-    public function getRoutes()
-    {
-        return [
-            ['/null_request', 'Symfony\Component\HttpFoundation\Request'],
-            ['/null_argument', ''],
-            ['/null_argument_with_route_param', ''],
-            ['/null_argument_with_route_param/value', 'value'],
-            ['/argument_with_route_param_and_default', 'value'],
-            ['/argument_with_route_param_and_default/custom', 'custom'],
-        ];
+        return 'AnnotatedController';
     }
 }

Tests/Functional/Bundle/TestBundle/Controller/AnnotatedController.php

@@ -17,42 +17,32 @@
 
 class AnnotatedController
 {
-    /**
-     * @Route("/null_request", name="null_request")
-     */
-    public function requestDefaultNullAction(Request $request = null)
+    #[Route('/null_request', name: 'null_request')]
+    public function requestDefaultNullAction(Request $request = null): Response
     {
         return new Response($request ? $request::class : null);
     }
 
-    /**
-     * @Route("/null_argument", name="null_argument")
-     */
-    public function argumentDefaultNullWithoutRouteParamAction($value = null)
+    #[Route('/null_argument', name: 'null_argument')]
+    public function argumentDefaultNullWithoutRouteParamAction($value = null): Response
     {
         return new Response($value);
     }
 
-    /**
-     * @Route("/null_argument_with_route_param/{value}", name="null_argument_with_route_param")
-     */
-    public function argumentDefaultNullWithRouteParamAction($value = null)
+    #[Route('/null_argument_with_route_param/{value}', name: 'null_argument_with_route_param')]
+    public function argumentDefaultNullWithRouteParamAction($value = null): Response
     {
         return new Response($value);
     }
 
-    /**
-     * @Route("/argument_with_route_param_and_default/{value}", defaults={"value": "value"}, name="argument_with_route_param_and_default")
-     */
-    public function argumentWithoutDefaultWithRouteParamAndDefaultAction($value)
+    #[Route('/argument_with_route_param_and_default/{value}', defaults: ['value' => 'value'], name: 'argument_with_route_param_and_default')]
+    public function argumentWithoutDefaultWithRouteParamAndDefaultAction($value): Response
     {
         return new Response($value);
     }
 
-    /**
-     * @Route("/create-transaction")
-     */
-    public function createTransaction()
+    #[Route('/create-transaction')]
+    public function createTransaction(): Response
     {
         return new Response();
     }

Tests/Functional/Psr4RoutingTest.php

@@ -0,0 +1,23 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bundle\FrameworkBundle\Tests\Functional;
+
+/**
+ * @requires function Symfony\Component\Routing\Loader\Psr4DirectoryLoader::__construct
+ */
+final class Psr4RoutingTest extends AbstractAttributeRoutingTest
+{
+    protected function getTestCaseApp(): string
+    {
+        return 'Psr4Routing';
+    }
+}

Tests/Functional/app/Psr4Routing/bundles.php

@@ -0,0 +1,18 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+use Symfony\Bundle\FrameworkBundle\FrameworkBundle;
+use Symfony\Bundle\FrameworkBundle\Tests\Functional\Bundle\TestBundle\TestBundle;
+
+return [
+    new FrameworkBundle(),
+    new TestBundle(),
+];

Tests/Functional/app/Psr4Routing/config.yml

@@ -0,0 +1,2 @@
+imports:
+    - { resource: ../config/default.yml }

Tests/Functional/app/Psr4Routing/routing.yml

@@ -0,0 +1,4 @@
+test_bundle:
+    prefix:   /annotated
+    resource: "@TestBundle/Controller"
+    type:     attribute@Symfony\Bundle\FrameworkBundle\Tests\Functional\Bundle\TestBundle\Controller