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<?php |
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/** |
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* MCP protocol version negotiation. |
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* |
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* @package McpAdapter |
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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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/** |
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* Negotiates the MCP protocol version between client and server. |
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* |
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* If the client requests a supported version, the server echoes it back. |
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* Otherwise the server falls back to the latest supported version. |
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* |
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* This is a Core layer class — no WordPress function calls. |
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* |
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* @since 0.5.0 |
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*/ |
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final class McpVersionNegotiator { |
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|
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/** |
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* Protocol versions supported by this server, ordered newest-first. |
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* |
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* @var array<int, string> |
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*/ |
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// phpcs:ignore SlevomatCodingStandard.Classes.DisallowMultiConstantDefinition -- False positive: sniff mistakes array() commas for multi-const commas (only handles short syntax). |
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public const SUPPORTED_PROTOCOL_VERSIONS = array( |
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'2025-11-25', |
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'2025-06-18', |
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'2024-11-05', |
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); |
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|
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/** |
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* Negotiate the protocol version to use for a session. |
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* |
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* If the client-requested version is in the supported list it is echoed |
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* back verbatim. Otherwise the latest supported version is returned. |
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* |
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* @since 0.5.0 |
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* |
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* @param string $client_version The protocol version requested by the client. |
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* |
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* @return string The negotiated protocol version. |
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*/ |
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public static function negotiate( string $client_version ): string { |
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if ( in_array( $client_version, self::SUPPORTED_PROTOCOL_VERSIONS, true ) ) { |
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return $client_version; |
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} |
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|
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return self::SUPPORTED_PROTOCOL_VERSIONS[0]; |
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} |
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|
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/** |
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* Check whether a given version string is supported. |
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* |
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* @since 0.5.0 |
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* |
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* @param string $version The protocol version to check. |
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* |
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* @return bool True when the version is in the supported list, false otherwise. |
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*/ |
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public static function is_supported( string $version ): bool { |
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return in_array( $version, self::SUPPORTED_PROTOCOL_VERSIONS, true ); |
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} |
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} |
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|
