refactor: transport agnostic examples (#131)

examples/env-variables/EnvToolHandler.php

@@ -0,0 +1,51 @@
+<?php
+
+/*
+ * This file is part of the official PHP MCP SDK.
+ *
+ * A collaboration between Symfony and the PHP Foundation.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Mcp\Example\EnvVariables;
+
+use Mcp\Capability\Attribute\McpTool;
+
+final class EnvToolHandler
+{
+    /**
+     * Performs an action that can be modified by an environment variable.
+     * The MCP client should set 'APP_MODE' in its 'env' config for this server.
+     *
+     * @param string $input some input data
+     *
+     * @return array<string, string|int> the result, varying by APP_MODE
+     */
+    #[McpTool(name: 'process_data_by_mode')]
+    public function processData(string $input): array
+    {
+        $appMode = getenv('APP_MODE'); // Read from environment
+
+        if ('debug' === $appMode) {
+            return [
+                'mode' => 'debug',
+                'processed_input' => strtoupper($input),
+                'message' => 'Processed in DEBUG mode.',
+            ];
+        } elseif ('production' === $appMode) {
+            return [
+                'mode' => 'production',
+                'processed_input_length' => \strlen($input),
+                'message' => 'Processed in PRODUCTION mode (summary only).',
+            ];
+        } else {
+            return [
+                'mode' => $appMode ?: 'default',
+                'original_input' => $input,
+                'message' => 'Processed in default mode (APP_MODE not recognized or not set).',
+            ];
+        }
+    }
+}

examples/env-variables/server.php

@@ -0,0 +1,61 @@
+#!/usr/bin/env php
+<?php
+
+/*
+ * This file is part of the official PHP MCP SDK.
+ *
+ * A collaboration between Symfony and the PHP Foundation.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+require_once dirname(__DIR__).'/bootstrap.php';
+chdir(__DIR__);
+
+use Mcp\Server;
+
+/*
+    |--------------------------------------------------------------------------
+    | MCP Environment Variable Example Server
+    |--------------------------------------------------------------------------
+    |
+    | This server demonstrates how to use environment variables to modify tool
+    | behavior. The MCP client can set the APP_MODE environment variable to
+    | control the server's behavior.
+    |
+    | Configure your MCP Client (e.g. Cursor) for this server like this:
+    |
+    | {
+    |     "mcpServers": {
+    |         "my-php-env-server": {
+    |             "command": "php",
+    |             "args": ["/full/path/to/examples/05-stdio-env-variables/server.php"],
+    |             "env": {
+    |                 "APP_MODE": "debug" // or "production", or leave it out
+    |             }
+    |         }
+    |     }
+    | }
+    |
+    | The server will read the APP_MODE environment variable and use it to
+    | modify the behavior of the tools.
+    |
+    | If the APP_MODE environment variable is not set, the server will use the
+    | default behavior.
+    |
+*/
+
+logger()->info('Starting MCP Environment Variable Example Server...');
+
+$server = Server::builder()
+    ->setServerInfo('Env Var Server', '1.0.0')
+    ->setLogger(logger())
+    ->setDiscovery(__DIR__)
+    ->build();
+
+$result = $server->run(transport());
+
+logger()->info('Server listener stopped gracefully.', ['result' => $result]);
+
+shutdown($result);