symfony · nicolas-grekas · Aug 14, 2025 · Aug 14, 2025
diff --git a/UPGRADE-7.4.md b/UPGRADE-7.4.md
@@ -52,6 +52,13 @@ HttpFoundation
 
  * Deprecate using `Request::sendHeaders()` after headers have already been sent; use a `StreamedResponse` instead
 
+HttpKernel
+----------
+
+ * Deprecate implementing `__sleep/wakeup()` on kernels; use `__(un)serialize()` instead
+ * Deprecate implementing `__sleep/wakeup()` on data collectors; use `__(un)serialize()` instead
+ * Make `Profile` final and `Profiler::__sleep()` internal
+
 Security
 --------
 

diff --git a/src/Symfony/Bundle/WebProfilerBundle/Tests/Profiler/TemplateManagerTest.php b/src/Symfony/Bundle/WebProfilerBundle/Tests/Profiler/TemplateManagerTest.php
@@ -13,6 +13,9 @@
 
 use Symfony\Bundle\WebProfilerBundle\Profiler\TemplateManager;
 use Symfony\Bundle\WebProfilerBundle\Tests\TestCase;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\HttpKernel\DataCollector\DataCollector;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 use Symfony\Component\HttpKernel\Profiler\Profile;
 use Symfony\Component\HttpKernel\Profiler\Profiler;
@@ -57,7 +60,10 @@ public function testGetNameValidTemplate()
             ->withAnyParameters()
             ->willReturnCallback($this->profilerHasCallback(...));
 
-        $this->assertEquals('@Foo/Collector/foo.html.twig', $this->templateManager->getName(new ProfileDummy(), 'foo'));
+        $profile = new Profile('token');
+        $profile->addCollector(new DummyCollector('foo'));
+        $profile->addCollector(new DummyCollector('bar'));
+        $this->assertEquals('@Foo/Collector/foo.html.twig', $this->templateManager->getName($profile, 'foo'));
     }
 
     public function profilerHasCallback($panel)
@@ -94,19 +100,18 @@ protected function mockTwigEnvironment()
     }
 }
 
-class ProfileDummy extends Profile
+class DummyCollector extends DataCollector
 {
-    public function __construct()
+    public function __construct(private string $name)
     {
-        parent::__construct('token');
     }
 
-    public function hasCollector(string $name): bool
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    public function collect(Request $request, Response $response, ?\Throwable $exception = null): void
     {
-        return match ($name) {
-            'foo',
-            'bar' => true,
-            default => false,
-        };
     }
 }
diff --git a/src/Symfony/Component/HttpKernel/CHANGELOG.md b/src/Symfony/Component/HttpKernel/CHANGELOG.md
@@ -1,6 +1,13 @@
 CHANGELOG
 =========
 
+7.4
+---
+
+ * Deprecate implementing `__sleep/wakeup()` on kernels; use `__(un)serialize()` instead
+ * Deprecate implementing `__sleep/wakeup()` on data collectors; use `__(un)serialize()` instead
+ * Make `Profile` final and `Profiler::__sleep()` internal
+
 7.3
 ---
 

diff --git a/src/Symfony/Component/HttpKernel/DataCollector/DataCollector.php b/src/Symfony/Component/HttpKernel/DataCollector/DataCollector.php
@@ -84,26 +84,67 @@
         ] + ReflectionCaster::UNSET_CLOSURE_FILE_INFO;
     }
 
-    public function __sleep(): array
+    public function __serialize(): array
     {
-        return ['data'];
+        if (self::class === (new \ReflectionMethod($this, '__sleep'))->class) {
+            return ['data' => $this->data];
+        }
+
+        trigger_deprecation('symfony/http-kernel', '7.4', 'Implementing "%s::__sleep()" is deprecated, use "__serialize()" instead.', get_debug_type($this));
+
+        $data = [];
+        foreach ($this->__sleep() as $key) {
+            try {
+                if (($r = new \ReflectionProperty($this, $key))->isInitialized($this)) {
+                    $data[$key] = $r->getValue($this);
+                }
+            } catch (\ReflectionException) {
+                $data[$key] = $this->$key;
+            }
+        }
+
+        return $data;
     }
 
-    public function __wakeup(): void
+    public function __unserialize(array $data): void
     {
+        if (self::class !== (new \ReflectionMethod($this, '__wakeup'))->class) {
+            trigger_deprecation('symfony/http-kernel', '7.4', 'Implementing "%s::__wakeup()" is deprecated, use "__unserialize()" instead.', get_debug_type($this));
+        }
+
+        if (\in_array(array_keys($data), [['data'], ["\0*\0data"]], true)) {
+            $this->data = $data['data'] ?? $data["\0*\0data"];
+
+            return;
+        }
+
+        trigger_deprecation('symfony/http-kernel', '7.4', 'Passing more than just key "data" to "%s::__unserialize()" is deprecated, populate properties in "%s::__unserialize()" instead.', self::class, get_debug_type($this));
+
+        \Closure::bind(function ($data) {
+            foreach ($data as $key => $value) {
+                $this->{("\0" === $key[0] ?? '') ? substr($key, 1 + strrpos($key, "\0")) : $key} = $value;
+            }
+
+            $this->__wakeup();
+        }, $this, static::class)($data);
     }
 
     /**
-     * @internal to prevent implementing \Serializable
+     * @internal since Symfony 7.4, will be removed in 8.0
+     *
+     * @final since Symfony 7.4, will be removed in 8.0
      */
-    final protected function serialize(): void
+    public function __sleep(): array
     {
+        return ['data'];
     }
 
     /**
-     * @internal to prevent implementing \Serializable
+     * @internal since Symfony 7.4, will be removed in 8.0
+     *
+     * @final since Symfony 7.4, will be removed in 8.0
      */
-    final protected function unserialize(string $data): void
+    public function __wakeup(): void
     {
     }
 

diff --git a/src/Symfony/Component/HttpKernel/Kernel.php b/src/Symfony/Component/HttpKernel/Kernel.php
@@ -775,11 +775,70 @@
         return $container;
     }
 
+    public function __serialize(): array
+    {
+        if (self::class === (new \ReflectionMethod($this, '__sleep'))->class) {
+            return [
+                'environment' => $this->environment,
+                'debug' => $this->debug,
+            ];
+        }
+
+        trigger_deprecation('symfony/http-kernel', '7.4', 'Implementing "%s::__sleep()" is deprecated, use "__serialize()" instead.', get_debug_type($this));
+
+        $data = [];
+        foreach ($this->__sleep() as $key) {
+            try {
+                if (($r = new \ReflectionProperty($this, $key))->isInitialized($this)) {
+                    $data[$key] = $r->getValue($this);
+                }
+            } catch (\ReflectionException) {
+                $data[$key] = $this->$key;
+            }
+        }
+
+        return $data;
+    }
+
+    public function __unserialize(array $data): void
+    {
+        if (self::class !== (new \ReflectionMethod($this, '__wakeup'))->class) {
+            trigger_deprecation('symfony/http-kernel', '7.4', 'Implementing "%s::__wakeup()" is deprecated, use "__unserialize()" instead.', get_debug_type($this));
+        }
+
+        if (\in_array(array_keys($data), [['environment', 'debug'], ["\0*\0environment", "\0*\0debug"]], true)) {
+            $this->environment = $data['environment'] ?? $data["\0*\0environment"];
+            $this->debug = $data['debug'] ?? $data["\0*\0debug"];
+
+            return;
+        }
+
+        trigger_deprecation('symfony/http-kernel', '7.4', 'Passing more than just key "environment" and "debug" to "%s::__unserialize()" is deprecated, populate properties in "%s::__unserialize()" instead.', self::class, get_debug_type($this));
+
+        \Closure::bind(function ($data) {
+            foreach ($data as $key => $value) {
+                $this->{("\0" === $key[0] ?? '') ? substr($key, 1 + strrpos($key, "\0")) : $key} = $value;
+            }
+
+            $this->__wakeup();
+        }, $this, static::class)($data);
+    }
+
+    /**
+     * @internal since Symfony 7.4, will be removed in 8.0
+     *
+     * @final since Symfony 7.4, will be removed in 8.0
+     */
     public function __sleep(): array
     {
         return ['environment', 'debug'];
     }
 
+    /**
+     * @internal since Symfony 7.4, will be removed in 8.0
+     *
+     * @final since Symfony 7.4, will be removed in 8.0
+     */
     public function __wakeup(): void
     {
         if (\is_object($this->environment) || \is_object($this->debug)) {

diff --git a/src/Symfony/Component/HttpKernel/Profiler/Profile.php b/src/Symfony/Component/HttpKernel/Profiler/Profile.php
@@ -14,9 +14,9 @@
 use Symfony\Component\HttpKernel\DataCollector\DataCollectorInterface;
 
 /**
- * Profile.
- *
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @final since Symfony 7.4
  */
 class Profile
 {
@@ -248,6 +248,9 @@ public function hasCollector(string $name): bool
         return isset($this->collectors[$name]);
     }
 
+    /**
+     * @internal since Symfony 7.4, will be replaced by `__serialize()` in 8.0
+     */
     public function __sleep(): array
     {
         return ['token', 'parent', 'children', 'collectors', 'ip', 'method', 'url', 'time', 'statusCode', 'virtualType'];

diff --git a/src/Symfony/Component/HttpKernel/Tests/KernelTest.php b/src/Symfony/Component/HttpKernel/Tests/KernelTest.php
@@ -246,7 +246,7 @@ public function testSerialize()
         $env = 'test_env';
         $debug = true;
         $kernel = new KernelForTest($env, $debug);
-        $expected = \sprintf("O:48:\"%s\":2:{s:14:\"\0*\0environment\";s:8:\"test_env\";s:8:\"\0*\0debug\";b:1;}", KernelForTest::class);
+        $expected = \sprintf('O:48:"%s":2:{s:11:"environment";s:8:"test_env";s:5:"debug";b:1;}', KernelForTest::class);
         $this->assertEquals($expected, serialize($kernel));
     }