Fix to make Symfony Finder component optional

Author: bigdevlarry

CHANGELOG.md

@@ -2,6 +2,11 @@
 
 All notable changes to `mcp/sdk` will be documented in this file.
 
+0.6.0
+-----
+
+* [BC break] Make Symfony Finder component optional. Users would need to install `symfony/finder` now themselves
+
 0.5.0
 -----
 

composer.json

@@ -32,9 +32,11 @@
     "psr/http-server-handler": "^1.0",
     "psr/http-server-middleware": "^1.0",
     "psr/log": "^1.0 || ^2.0 || ^3.0",
-    "symfony/finder": "^5.4 || ^6.4 || ^7.3 || ^8.0",
     "symfony/uid": "^5.4 || ^6.4 || ^7.3 || ^8.0"
   },
+  "suggest": {
+    "symfony/finder": "Required for file-based discovery."
+  },
   "require-dev": {
     "ext-openssl": "*",
     "composer/semver": "^3.0",
@@ -50,6 +52,7 @@
     "psr/simple-cache": "^2.0 || ^3.0",
     "symfony/cache": "^5.4 || ^6.4 || ^7.3 || ^8.0",
     "symfony/console": "^5.4 || ^6.4 || ^7.3 || ^8.0",
+    "symfony/finder": "^5.4 || ^6.4 || ^7.3 || ^8.0",
     "symfony/http-client": "^5.4 || ^6.4 || ^7.3 || ^8.0",
     "symfony/process": "^5.4 || ^6.4 || ^7.3 || ^8.0"
   },

src/Capability/Discovery/Discoverer.php

@@ -24,6 +24,7 @@
 use Mcp\Capability\Registry\ResourceTemplateReference;
 use Mcp\Capability\Registry\ToolReference;
 use Mcp\Exception\ExceptionInterface;
+use Mcp\Exception\RuntimeException;
 use Mcp\Schema\Prompt;
 use Mcp\Schema\PromptArgument;
 use Mcp\Schema\Resource;
@@ -53,6 +54,10 @@ public function __construct(
         private ?DocBlockParser $docBlockParser = null,
         private ?SchemaGeneratorInterface $schemaGenerator = null,
     ) {
+        if (!class_exists(Finder::class)) {
+            throw new RuntimeException('File-based discovery requires symfony/finder. Run: composer require symfony/finder');
+        }
+
         $this->docBlockParser = $docBlockParser ?? new DocBlockParser(logger: $this->logger);
         $this->schemaGenerator = $schemaGenerator ?? new SchemaGenerator($this->docBlockParser);
     }

src/Server/Builder.php

@@ -46,6 +46,7 @@
 use Psr\Log\LoggerInterface;
 use Psr\Log\NullLogger;
 use Psr\SimpleCache\CacheInterface;
+use Symfony\Component\Finder\Finder;
 
 /**
  * @phpstan-import-type Handler from ElementReference
@@ -523,8 +524,12 @@ public function build(): Server
         );
 
         if (null !== $this->discoveryBasePath) {
-            $discoverer = $this->discoverer ?? $this->createDiscoverer($logger);
-            $loaders[] = new DiscoveryLoader($this->discoveryBasePath, $this->discoveryScanDirs, $this->discoveryExcludeDirs, $discoverer);
+            if (null !== $this->discoverer || class_exists(Finder::class)) {
+                $discoverer = $this->discoverer ?? $this->createDiscoverer($logger);
+                $loaders[] = new DiscoveryLoader($this->discoveryBasePath, $this->discoveryScanDirs, $this->discoveryExcludeDirs, $discoverer);
+            } else {
+                $logger->warning('File-based discovery requires symfony/finder. Skipping automatic discovery. Run: composer require symfony/finder');
+            }
         }
 
         foreach ($loaders as $loader) {