feature #23570 [FrameworkBundle] Make RouterCacheWarmer implement ServiceSubscriberInterface (nicolas-grekas)

This PR was merged into the 3.4 branch.

Discussion
----------

[FrameworkBundle] Make RouterCacheWarmer implement ServiceSubscriberInterface

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | yes
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Blocks #23569

Commits
-------

c0af0031ec [FrameworkBundle] Make RouterCacheWarmer implement ServiceSubscriberInterface

src/Symfony/Bridge/Twig/Extension/RoutingExtension.php

@@ -91,7 +91,7 @@ class RoutingExtension extends AbstractExtension
      *
      * @return array An array with the contexts the URL is safe
      *
-     * To be made @final in 3.4, and the type-hint be changed to "\Twig\Node\Node" in 4.0.
+     * @final since version 3.4, type-hint to be changed to "\Twig\Node\Node" in 4.0
      */
     public function isUrlGenerationSafe(\Twig_Node $argsNode)
     {

src/Symfony/Bundle/FrameworkBundle/CacheWarmer/RouterCacheWarmer.php

@@ -11,6 +11,8 @@
 
 namespace Symfony\Bundle\FrameworkBundle\CacheWarmer;
 
+use Psr\Container\ContainerInterface;
+use Symfony\Component\DependencyInjection\ServiceSubscriberInterface;
 use Symfony\Component\HttpKernel\CacheWarmer\CacheWarmerInterface;
 use Symfony\Component\HttpKernel\CacheWarmer\WarmableInterface;
 use Symfony\Component\Routing\RouterInterface;
@@ -20,20 +22,28 @@ use Symfony\Component\Routing\RouterInterface;
  *
  * @author Fabien Potencier <fabien@symfony.com>
  *
- * @final since version 3.4, to be given a container instead in 4.0
+ * @final since version 3.4
  */
-class RouterCacheWarmer implements CacheWarmerInterface
+class RouterCacheWarmer implements CacheWarmerInterface, ServiceSubscriberInterface
 {
     protected $router;
 
     /**
      * Constructor.
      *
-     * @param RouterInterface $router A Router instance
+     * @param ContainerInterface $container
      */
-    public function __construct(RouterInterface $router)
+    public function __construct($container)
     {
-        $this->router = $router;
+        // As this cache warmer is optional, dependencies should be lazy-loaded, that's why a container should be injected.
+        if ($container instanceof ContainerInterface) {
+            $this->router = $container->get('router'); // For BC, the $router property must be populated in the constructor
+        } elseif ($container instanceof RouterInterface) {
+            $this->router = $container;
+            @trigger_error(sprintf('Using a "%s" as first argument of %s is deprecated since version 3.4 and will be unsupported in version 4.0. Use a %s instead.', RouterInterface::class, __CLASS__, ContainerInterface::class), E_USER_DEPRECATED);
+        } else {
+            throw new \InvalidArgumentException(sprintf('%s only accepts instance of Psr\Container\ContainerInterface as first argument.', __CLASS__));
+        }
     }
 
     /**
@@ -57,4 +67,14 @@ class RouterCacheWarmer implements CacheWarmerInterface
     {
         return true;
     }
+
+    /**
+     * {@inheritdoc}
+     */
+    public static function getSubscribedServices()
+    {
+        return array(
+            'router' => RouterInterface::class,
+        );
+    }
 }

src/Symfony/Bundle/FrameworkBundle/Resources/config/routing.xml

@@ -97,8 +97,9 @@
         <service id="Symfony\Component\Routing\RequestContext" alias="router.request_context" />
 
         <service id="router.cache_warmer" class="Symfony\Bundle\FrameworkBundle\CacheWarmer\RouterCacheWarmer">
+            <tag name="container.service_subscriber" id="router" />
             <tag name="kernel.cache_warmer" />
-            <argument type="service" id="router" />
+            <argument type="service" id="Psr\Container\ContainerInterface" />
         </service>
 
         <service id="router_listener" class="Symfony\Component\HttpKernel\EventListener\RouterListener" public="true">