make callback async

Author: ihrpr

src/mcp/shared/session.py

@@ -46,7 +46,7 @@
 class ProgressFnT(Protocol):
     """Protocol for progress notification callbacks."""
 
-    def __call__(
+    async def __call__(
         self, progress: float, total: float | None, message: str | None
     ) -> None: ...
 
@@ -392,7 +392,7 @@ async def _receive_loop(self) -> None:
                                 # call it with the progress information
                                 if progress_token in self._progress_callbacks:
                                     callback = self._progress_callbacks[progress_token]
-                                    callback(
+                                    await callback(
                                         notification.root.params.progress,
                                         notification.root.params.total,
                                         notification.root.params.message,

tests/server/fastmcp/test_integration.py

@@ -655,10 +655,10 @@ async def call_all_mcp_features(
     # Test progress callback functionality
     progress_updates = []
 
-    def progress_callback(
+    async def progress_callback(
         progress: float, total: float | None, message: str | None
     ) -> None:
-        """Collect progress updates for testing."""
+        """Collect progress updates for testing (async version)."""
         progress_updates.append((progress, total, message))
         print(f"Progress: {progress}/{total} - {message}")