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<?php |
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/** |
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* WordPress MCP Registry - Main class for managing multiple MCP servers. |
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* |
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* @package WP\MCP\Core |
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*/ |
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|
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declare( strict_types=1 ); |
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|
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namespace WP\MCP\Core; |
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|
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use WP\MCP\Abilities\DiscoverAbilitiesAbility; |
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use WP\MCP\Abilities\ExecuteAbilityAbility; |
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use WP\MCP\Abilities\GetAbilityInfoAbility; |
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use WP\MCP\Cli\McpCommand; |
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use WP\MCP\Infrastructure\ErrorHandling\Contracts\McpErrorHandlerInterface; |
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use WP\MCP\Infrastructure\ErrorHandling\NullMcpErrorHandler; |
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use WP\MCP\Infrastructure\Observability\Contracts\McpObservabilityHandlerInterface; |
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use WP\MCP\Infrastructure\Observability\NullMcpObservabilityHandler; |
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use WP\MCP\Servers\DefaultServerFactory; |
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use WP_Error; |
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|
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/** |
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* WordPress MCP Registry - Main class for managing multiple MCP servers. |
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*/ |
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final class McpAdapter { |
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|
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public const VERSION = '0.5.0'; |
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|
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/** |
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* Registry instance |
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* |
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* @var \WP\MCP\Core\McpAdapter |
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*/ |
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private static self $instance; |
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/** |
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* Track if the adapter has been initialized to prevent duplicate initialization |
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* |
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* @var bool |
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*/ |
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private static bool $initialized = false; |
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/** |
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* Registered servers |
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* |
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* @var \WP\MCP\Core\McpServer[] |
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*/ |
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private array $servers = array(); |
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|
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/** |
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* Get the registry instance |
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* |
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* @return \WP\MCP\Core\McpAdapter |
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*/ |
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public static function instance(): self { |
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if ( ! isset( self::$instance ) ) { |
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self::$instance = new self(); |
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|
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// In WP-CLI context, initialize immediately so commands have access to servers |
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if ( defined( 'WP_CLI' ) && constant( 'WP_CLI' ) ) { |
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add_action( 'init', array( self::$instance, 'init' ), 20 ); |
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} else { |
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// Initialize for REST API requests with reasonable priority |
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add_action( 'rest_api_init', array( self::$instance, 'init' ), 15 ); |
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} |
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} |
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|
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return self::$instance; |
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} |
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|
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/** |
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* Initialize the registry |
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* |
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* @internal For use by instance initialization only. |
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*/ |
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public function init(): void { |
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if ( self::$initialized ) { |
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return; |
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} |
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|
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$this->maybe_create_default_server(); |
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|
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/** |
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* Fires after the MCP Adapter has been initialized. |
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* |
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* Use this action to register custom MCP servers. The adapter instance |
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* provides methods to create and configure additional servers beyond |
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* the default server. |
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* |
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* @since 0.1.0 |
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* |
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* @param \WP\MCP\Core\McpAdapter $adapter The MCP Adapter singleton instance. |
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*/ |
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do_action( 'mcp_adapter_init', $this ); |
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$this->register_wp_cli_commands(); |
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self::$initialized = true; |
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} |
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|
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/** |
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* Conditionally create the default server based on filter. |
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* |
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* @internal For use by adapter initialization only. |
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*/ |
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private function maybe_create_default_server(): void { |
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/** |
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* Filters whether the default MCP server should be created. |
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* |
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* Return false to prevent the default server from being created. |
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* This is useful when you want to define custom servers only. |
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* |
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* @since 0.3.0 |
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* |
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* @param bool $create_default Whether to create the default server. Default true. |
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*/ |
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if ( ! apply_filters( 'mcp_adapter_create_default_server', true ) ) { |
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return; |
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} |
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|
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// Register category before abilities |
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add_action( 'wp_abilities_api_categories_init', array( $this, 'register_default_category' ) ); |
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add_action( 'wp_abilities_api_init', array( $this, 'register_default_abilities' ) ); |
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|
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add_action( 'mcp_adapter_init', array( DefaultServerFactory::class, 'create' ) ); |
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} |
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|
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/** |
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* Register WP-CLI commands if WP-CLI is available |
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* |
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* @internal For use by adapter initialization only. |
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*/ |
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private function register_wp_cli_commands(): void { |
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// Only register if WP-CLI is available |
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if ( ! defined( 'WP_CLI' ) || ! constant( 'WP_CLI' ) ) { |
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return; |
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} |
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|
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if ( ! class_exists( '\WP_CLI' ) ) { |
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return; |
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} |
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|
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\WP_CLI::add_command( |
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'mcp-adapter', |
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McpCommand::class, |
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array( |
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'shortdesc' => 'Manage MCP servers via WP-CLI.', |
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'longdesc' => 'Commands for managing and serving MCP servers, including STDIO transport.', |
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) |
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); |
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} |
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|
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/** |
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* Create and register a new MCP server. |
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* |
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* @param string $server_id Unique identifier for the server. |
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* @param string $server_route_namespace Server route namespace. |
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* @param string $server_route Server route. |
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* @param string $server_name Server name. |
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* @param string $server_description Server description. |
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* @param string $server_version Server version. |
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* @param array<class-string<\WP\MCP\Transport\Contracts\McpTransportInterface>> $mcp_transports Array of MCP transport class names to initialize. |
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* @param class-string<\WP\MCP\Infrastructure\ErrorHandling\Contracts\McpErrorHandlerInterface>|null $error_handler The error handler class name. If null, NullMcpErrorHandler will be used. |
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* @param class-string<\WP\MCP\Infrastructure\Observability\Contracts\McpObservabilityHandlerInterface>|null $observability_handler The observability handler class name. If null, NullMcpObservabilityHandler will be used. |
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* @param list<string> $tools Ability names to register as tools. |
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* @param list<string> $resources Resources to register. |
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* @param list<string> $prompts Prompts to register. |
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* @param callable|null $transport_permission_callback Optional custom permission callback for transport-level authentication. If null, defaults to is_user_logged_in(). |
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* |
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* @return \WP\MCP\Core\McpAdapter|\WP_Error McpAdapter instance on success, WP_Error on failure. |
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*/ |
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public function create_server( string $server_id, string $server_route_namespace, string $server_route, string $server_name, string $server_description, string $server_version, array $mcp_transports, ?string $error_handler, ?string $observability_handler = null, array $tools = array(), array $resources = array(), array $prompts = array(), ?callable $transport_permission_callback = null ) { |
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// Use NullMcpErrorHandler if no error handler is provided. |
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if ( ! $error_handler ) { |
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$error_handler = NullMcpErrorHandler::class; |
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} |
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|
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// Validate error handler class exists and implements McpErrorHandlerInterface. |
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if ( ! class_exists( $error_handler ) ) { |
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return new WP_Error( |
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'invalid_error_handler', |
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sprintf( |
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/* translators: %s: error handler class name */ |
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esc_html__( 'Error handler class "%s" does not exist.', 'mcp-adapter' ), |
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esc_html( $error_handler ) |
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) |
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); |
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} |
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|
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if ( ! in_array( McpErrorHandlerInterface::class, class_implements( $error_handler ) ?: array(), true ) ) { |
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return new WP_Error( |
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'invalid_error_handler', |
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sprintf( |
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/* translators: %s: error handler class name */ |
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esc_html__( 'Error handler class "%s" must implement the McpErrorHandlerInterface.', 'mcp-adapter' ), |
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esc_html( $error_handler ) |
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) |
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); |
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} |
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|
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// Use NullMcpObservabilityHandler if no observability handler is provided. |
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if ( ! $observability_handler ) { |
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$observability_handler = NullMcpObservabilityHandler::class; |
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} |
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|
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// Validate observability handler class exists and implements McpObservabilityHandlerInterface. |
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if ( ! class_exists( $observability_handler ) ) { |
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return new WP_Error( |
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'invalid_observability_handler', |
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sprintf( |
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/* translators: %s: observability handler class name */ |
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esc_html__( 'Observability handler class "%s" does not exist.', 'mcp-adapter' ), |
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esc_html( $observability_handler ) |
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) |
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); |
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} |
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|
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if ( ! in_array( McpObservabilityHandlerInterface::class, class_implements( $observability_handler ) ?: array(), true ) ) { |
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return new WP_Error( |
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'invalid_observability_handler', |
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sprintf( |
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/* translators: %s: observability handler class name */ |
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esc_html__( 'Observability handler class "%s" must implement the McpObservabilityHandlerInterface interface.', 'mcp-adapter' ), |
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esc_html( $observability_handler ) |
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) |
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); |
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} |
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|
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if ( ! doing_action( 'mcp_adapter_init' ) ) { |
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_doing_it_wrong( |
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__FUNCTION__, |
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esc_html__( 'MCP Servers must be created during the "mcp_adapter_init" action. Hook into "mcp_adapter_init" to register your server.', 'mcp-adapter' ), |
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'0.1.0' |
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); |
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|
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return new WP_Error( |
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'invalid_timing', |
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esc_html__( 'MCP Server creation must be done during mcp_adapter_init action.', 'mcp-adapter' ) |
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); |
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} |
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|
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if ( isset( $this->servers[ $server_id ] ) ) { |
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_doing_it_wrong( |
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__FUNCTION__, |
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sprintf( |
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// translators: %s: server ID |
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esc_html__( 'Server with ID "%s" already exists. Each server must have a unique ID.', 'mcp-adapter' ), |
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esc_html( $server_id ) |
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), |
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'0.1.0' |
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); |
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|
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return new WP_Error( |
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'duplicate_server_id', |
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// translators: %s: server ID. |
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sprintf( esc_html__( 'Server with ID "%s" already exists.', 'mcp-adapter' ), esc_html( $server_id ) ) |
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); |
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} |
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|
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// Create server with tools, resources, and prompts - let server handle all registration logic. |
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try { |
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$server = new McpServer( |
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$server_id, |
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$server_route_namespace, |
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$server_route, |
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$server_name, |
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$server_description, |
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$server_version, |
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$mcp_transports, |
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$error_handler, |
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$observability_handler, |
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$tools, |
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$resources, |
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$prompts, |
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$transport_permission_callback |
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); |
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} catch ( \Throwable $e ) { |
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return new WP_Error( |
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'server_creation_failed', |
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sprintf( |
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/* translators: 1: server ID, 2: error message */ |
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esc_html__( 'Failed to create server "%1$s": %2$s', 'mcp-adapter' ), |
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esc_html( $server_id ), |
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esc_html( $e->getMessage() ) |
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) |
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); |
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} |
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|
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// Track server creation. |
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$server->get_observability_handler()->record_event( |
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'mcp.server.created', |
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array( |
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'status' => 'success', |
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'server_id' => $server_id, |
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'transport_count' => count( $mcp_transports ), |
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'tools_count' => count( $tools ), |
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'resources_count' => count( $resources ), |
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'prompts_count' => count( $prompts ), |
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) |
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); |
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|
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// Add server to registry. |
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$this->servers[ $server_id ] = $server; |
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|
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return $this; |
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} |
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|
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/** |
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* Get a server by ID. |
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* |
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* @param string $server_id Server ID. |
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* |
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* @return \WP\MCP\Core\McpServer|null |
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*/ |
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public function get_server( string $server_id ): ?McpServer { |
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return $this->servers[ $server_id ] ?? null; |
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} |
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|
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/** |
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* Get all registered servers |
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* |
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* @return \WP\MCP\Core\McpServer[] |
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*/ |
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public function get_servers(): array { |
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return $this->servers; |
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} |
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|
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/** |
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* Register the default MCP category. |
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* |
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* @return void |
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*/ |
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public function register_default_category(): void { |
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wp_register_ability_category( |
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'mcp-adapter', |
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array( |
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'label' => 'MCP Adapter', |
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'description' => 'Abilities for the MCP Adapter', |
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) |
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); |
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} |
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|
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/** |
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* Register the default MCP abilities. |
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* |
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* @return void |
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*/ |
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public function register_default_abilities(): void { |
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// Register the three core MCP abilities |
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DiscoverAbilitiesAbility::register(); |
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GetAbilityInfoAbility::register(); |
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ExecuteAbilityAbility::register(); |
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} |
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} |
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|
