Remove event dispatcher

Author: Bellangelo

composer.json

@@ -23,9 +23,7 @@
         "opis/json-schema": "^2.4",
         "phpdocumentor/reflection-docblock": "^5.6",
         "psr/container": "^2.0",
-        "psr/event-dispatcher": "^1.0",
         "psr/log": "^1.0 || ^2.0 || ^3.0",
-        "symfony/event-dispatcher": "^7.3",
         "symfony/finder": "^6.4 || ^7.3",
         "symfony/uid": "^6.4 || ^7.3"
     },

src/Capability/Registry.php

@@ -29,7 +29,7 @@
 use Mcp\Schema\ResourceTemplate;
 use Mcp\Schema\ServerCapabilities;
 use Mcp\Schema\Tool;
-use Psr\EventDispatcher\EventDispatcherInterface;
+use Mcp\Server\NotificationPublisher;
 use Psr\Log\LoggerInterface;
 use Psr\Log\NullLogger;
 
@@ -61,8 +61,8 @@ class Registry
     private array $resourceTemplates = [];
 
     public function __construct(
+        private readonly NotificationPublisher $notificationPublisher,
         private readonly ReferenceHandler $referenceHandler = new ReferenceHandler(),
-        private readonly ?EventDispatcherInterface $eventDispatcher = null,
         private readonly LoggerInterface $logger = new NullLogger(),
     ) {
     }
@@ -75,12 +75,12 @@ public function getCapabilities(): ServerCapabilities
 
         return new ServerCapabilities(
             tools: true, // [] !== $this->tools,
-            toolsListChanged: $this->eventDispatcher instanceof EventDispatcherInterface,
+            toolsListChanged: true,
             resources: [] !== $this->resources || [] !== $this->resourceTemplates,
             resourcesSubscribe: false,
-            resourcesListChanged: $this->eventDispatcher instanceof EventDispatcherInterface,
+            resourcesListChanged: true,
             prompts: [] !== $this->prompts,
-            promptsListChanged: $this->eventDispatcher instanceof EventDispatcherInterface,
+            promptsListChanged: true,
             logging: false, // true,
             completions: true,
         );
@@ -102,7 +102,7 @@ public function registerTool(Tool $tool, callable|array|string $handler, bool $i
 
         $this->tools[$toolName] = new ToolReference($tool, $handler, $isManual);
 
-        $this->eventDispatcher?->dispatch(new ToolListChangedEvent());
+        $this->notificationPublisher->enqueue(new ToolListChangedEvent());
     }
 
     /**
@@ -121,7 +121,7 @@ public function registerResource(Resource $resource, callable|array|string $hand
 
         $this->resources[$uri] = new ResourceReference($resource, $handler, $isManual);
 
-        $this->eventDispatcher?->dispatch(new ResourceListChangedEvent());
+        $this->notificationPublisher->enqueue(new ResourceListChangedEvent());
     }
 
     /**
@@ -145,7 +145,7 @@ public function registerResourceTemplate(
 
         $this->resourceTemplates[$uriTemplate] = new ResourceTemplateReference($template, $handler, $isManual, $completionProviders);
 
-        $this->eventDispatcher?->dispatch(new ResourceTemplateListChangedEvent());
+        $this->notificationPublisher->enqueue(new ResourceTemplateListChangedEvent());
     }
 
     /**
@@ -169,7 +169,7 @@ public function registerPrompt(
 
         $this->prompts[$promptName] = new PromptReference($prompt, $handler, $isManual, $completionProviders);
 
-        $this->eventDispatcher?->dispatch(new PromptListChangedEvent());
+        $this->notificationPublisher->enqueue(new PromptListChangedEvent());
     }
 
     /**

src/Server/NotificationPublisher.php

@@ -21,7 +21,6 @@
 use Mcp\Schema\Notification\PromptListChangedNotification;
 use Mcp\Schema\Notification\ResourceListChangedNotification;
 use Mcp\Schema\Notification\ToolListChangedNotification;
-use Symfony\Component\EventDispatcher\EventDispatcher;
 use Symfony\Contracts\EventDispatcher\Event;
 
 /**
@@ -46,16 +45,12 @@ public function __construct(
     ) {
     }
 
-    public static function make(EventDispatcher $eventDispatcher): self
+    public static function make(): self
     {
-        $instance = new self(MessageFactory::make());
-
-        $eventDispatcher->addListener(Event::class, [$instance, 'onEvent']);
-
-        return $instance;
+        return new self(MessageFactory::make());
     }
 
-    public function onEvent(Event $event): void
+    public function enqueue(Event $event): void
     {
         $eventClass = $event::class;
         if (!isset(self::EVENTS_TO_NOTIFICATIONS[$eventClass])) {

src/Server/ServerBuilder.php

@@ -33,12 +33,9 @@
 use Mcp\Schema\ToolAnnotations;
 use Mcp\Server;
 use Psr\Container\ContainerInterface;
-use Psr\EventDispatcher\EventDispatcherInterface;
 use Psr\Log\LoggerInterface;
 use Psr\Log\NullLogger;
 use Psr\SimpleCache\CacheInterface;
-use Symfony\Component\EventDispatcher\EventDispatcher;
-use Symfony\Contracts\EventDispatcher\Event;
 
 /**
  * @author Kyrian Obikwelu <koshnawaza@gmail.com>
@@ -51,8 +48,6 @@ final class ServerBuilder
 
     private ?CacheInterface $cache = null;
 
-    private ?EventDispatcherInterface $eventDispatcher = null;
-
     private ?ContainerInterface $container = null;
 
     private ?int $paginationLimit = 50;
@@ -144,13 +139,6 @@ public function withLogger(LoggerInterface $logger): self
         return $this;
     }
 
-    public function withEventDispatcher(EventDispatcherInterface $eventDispatcher): self
-    {
-        $this->eventDispatcher = $eventDispatcher;
-
-        return $this;
-    }
-
     /**
      * Provides a PSR-11 DI container, primarily for resolving user-defined handler classes.
      * Defaults to a basic internal container.
@@ -219,19 +207,10 @@ public function withPrompt(callable|array|string $handler, ?string $name = null,
      */
     public function build(): Server
     {
-        $internalDispatcher = new EventDispatcher();
-
-        if ($this->eventDispatcher instanceof EventDispatcherInterface) {
-            $internalDispatcher->addListener(
-                Event::class,
-                fn ($event) => $this->eventDispatcher?->dispatch($event)
-            );
-        }
-
         $logger = $this->logger ?? new NullLogger();
-
+        $notificationPublisher = NotificationPublisher::make();
         $container = $this->container ?? new Container();
-        $registry = new Registry(new ReferenceHandler($container), $internalDispatcher, $logger);
+        $registry = new Registry($notificationPublisher, new ReferenceHandler($container), $logger);
 
         $this->registerManualElements($registry, $logger);
 
@@ -242,7 +221,7 @@ public function build(): Server
 
         return new Server(
             Handler::make($registry, $this->serverInfo, $logger),
-            NotificationPublisher::make($internalDispatcher),
+            $notificationPublisher,
             $logger,
         );
     }

tests/Capability/Discovery/DiscoveryTest.php

@@ -19,6 +19,7 @@
 use Mcp\Capability\Registry\ResourceReference;
 use Mcp\Capability\Registry\ResourceTemplateReference;
 use Mcp\Capability\Registry\ToolReference;
+use Mcp\Server\NotificationPublisher;
 use Mcp\Tests\Capability\Attribute\CompletionProviderFixture;
 use Mcp\Tests\Capability\Discovery\Fixtures\DiscoverableToolHandler;
 use Mcp\Tests\Capability\Discovery\Fixtures\InvocablePromptFixture;
@@ -34,7 +35,7 @@ class DiscoveryTest extends TestCase
 
     protected function setUp(): void
     {
-        $this->registry = new Registry();
+        $this->registry = new Registry(NotificationPublisher::make());
         $this->discoverer = new Discoverer($this->registry);
     }
 

tests/Server/NotificationPublisherTest.php

@@ -31,7 +31,7 @@ public function testOnEventCreatesNotification(): void
         foreach (NotificationPublisher::EVENTS_TO_NOTIFICATIONS as $eventClass => $notificationClass) {
             /** @var Event $event */
             $event = new $eventClass();
-            $notificationPublisher->onEvent($event);
+            $notificationPublisher->enqueue($event);
             $expectedNotifications[] = $notificationClass;
         }