feat: add ClientCredentials

This data class contains creds plus auth method

Author: challenger71498

src/mcp/server/auth/middleware/client_auth.py

@@ -2,7 +2,8 @@
 import binascii
 import hmac
 import time
-from typing import Any
+from dataclasses import dataclass
+from typing import Any, Literal
 from urllib.parse import unquote
 
 from starlette.requests import Request
@@ -16,6 +17,13 @@ def __init__(self, message: str):
         self.message = message  # pragma: no cover
 
 
+@dataclass
+class ClientCredentials:
+    auth_method: Literal["client_secret_basic", "client_secret_post"]
+    client_id: str
+    client_secret: str | None = None
+
+
 class ClientAuthenticator:
     """
     ClientAuthenticator is a callable which validates requests from a client