[MCP Bundle] Make MonologBundle optional

src/mcp-bundle/composer.json

@@ -24,7 +24,8 @@
     "require-dev": {
         "phpstan/phpstan": "^2.1",
         "phpstan/phpstan-strict-rules": "^2.0",
-        "phpunit/phpunit": "^11.5"
+        "phpunit/phpunit": "^11.5",
+        "symfony/monolog-bundle": "^3.10"
     },
     "minimum-stability": "dev",
     "prefer-stable": true,

src/mcp-bundle/config/services.php

@@ -13,24 +13,33 @@
 
 use Mcp\Server;
 use Mcp\Server\Builder;
+use Symfony\Bundle\MonologBundle\MonologBundle;
 
 return static function (ContainerConfigurator $container): void {
-    $container->services()
-        ->set('monolog.logger.mcp')
-            ->parent('monolog.logger_prototype')
-            ->args(['mcp'])
-            ->tag('monolog.logger', ['channel' => 'mcp'])
+    if (class_exists(MonologBundle::class)) {
+        $container->services()
+            ->set('monolog.logger.mcp')
+                ->parent('monolog.logger_prototype')
+                ->args(['mcp'])
+                ->tag('monolog.logger', ['channel' => 'mcp'])
+        ;
+    }
 
+    $builderDefinition = $container->services()
         ->set('mcp.server.builder', Builder::class)
             ->factory([Server::class, 'builder'])
             ->call('setServerInfo', [param('mcp.app'), param('mcp.version')])
             ->call('setPaginationLimit', [param('mcp.pagination_limit')])
             ->call('setInstructions', [param('mcp.instructions')])
-            ->call('setLogger', [service('monolog.logger.mcp')])
             ->call('setEventDispatcher', [service('event_dispatcher')])
             ->call('setSession', [service('mcp.session.store')])
-            ->call('setDiscovery', [param('kernel.project_dir'), param('mcp.discovery.scan_dirs'), param('mcp.discovery.exclude_dirs')])
+            ->call('setDiscovery', [param('kernel.project_dir'), param('mcp.discovery.scan_dirs'), param('mcp.discovery.exclude_dirs')]);
+
+    if (class_exists(MonologBundle::class)) {
+        $builderDefinition->call('setLogger', [service('monolog.logger.mcp')]);
+    }
 
+    $container->services()
         ->set('mcp.server', Server::class)
             ->factory([service('mcp.server.builder'), 'build'])
 

src/mcp-bundle/src/Command/McpCommand.php

@@ -24,14 +24,16 @@ class McpCommand extends Command
 {
     public function __construct(
         private readonly Server $server,
-        private readonly LoggerInterface $logger,
+        private readonly ?LoggerInterface $logger = null,
     ) {
         parent::__construct();
     }
 
     protected function execute(InputInterface $input, OutputInterface $output): int
     {
-        $transport = new StdioTransport(logger: $this->logger);
+        $transport = $this->logger
+            ? new StdioTransport(logger: $this->logger)
+            : new StdioTransport();
         $this->server->run($transport);
 
         return Command::SUCCESS;

src/mcp-bundle/src/Controller/McpController.php

@@ -35,12 +35,18 @@ public function __construct(
 
     public function handle(Request $request): Response
     {
-        $transport = new StreamableHttpTransport(
-            $this->httpMessageFactory->createRequest($request),
-            $this->responseFactory,
-            $this->streamFactory,
-            logger: $this->logger,
-        );
+        $transport = $this->logger
+            ? new StreamableHttpTransport(
+                $this->httpMessageFactory->createRequest($request),
+                $this->responseFactory,
+                $this->streamFactory,
+                logger: $this->logger,
+            )
+            : new StreamableHttpTransport(
+                $this->httpMessageFactory->createRequest($request),
+                $this->responseFactory,
+                $this->streamFactory,
+            );
 
         return $this->httpFoundationFactory->createResponse(
             $this->server->run($transport),

src/mcp-bundle/src/McpBundle.php

@@ -114,7 +114,7 @@ private function configureClient(array $transports, array $httpConfig, Container
             $container->register('mcp.server.command', McpCommand::class)
                 ->setArguments([
                     new Reference('mcp.server'),
-                    new Reference('logger'),
+                    new Reference('monolog.logger.mcp', ContainerInterface::NULL_ON_INVALID_REFERENCE),
                 ])
                 ->addTag('console.command');
         }

src/mcp-bundle/tests/DependencyInjection/McpBundleTest.php

@@ -14,6 +14,7 @@
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 use Symfony\AI\McpBundle\McpBundle;
+use Symfony\Bundle\MonologBundle\MonologBundle;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 
 class McpBundleTest extends TestCase
@@ -49,6 +50,10 @@ public function testCustomConfiguration()
 
     public function testMcpLoggerServiceIsCreated()
     {
+        if (!class_exists(MonologBundle::class)) {
+            $this->markTestSkipped('MonologBundle is not installed');
+        }
+
         $container = $this->buildContainer([]);
 
         $this->assertTrue($container->hasDefinition('monolog.logger.mcp'));