modelcontextprotocol · jspahrsummers · Oct 3, 2024 · Oct 2, 2024
diff --git a/mcp_python/client/sse.py b/mcp_python/client/sse.py
@@ -104,7 +104,7 @@ async def post_writer(endpoint_url: str):
                                    logger.debug(f"Sending client message: {message}")
                                    response = await client.post(
                                        endpoint_url,
-                                        json=message.model_dump(by_alias=True, mode="json"),
+                                        json=message.model_dump(by_alias=True, mode="json", exclude_none=True),
                                    )
                                    response.raise_for_status()
                                    logger.debug(

diff --git a/mcp_python/client/stdio.py b/mcp_python/client/stdio.py
@@ -70,7 +70,7 @@ async def stdin_writer():
        try:
            async with write_stream_reader:
                async for message in write_stream_reader:
-                    json = message.model_dump_json(by_alias=True)
+                    json = message.model_dump_json(by_alias=True, exclude_none=True)
                    await process.stdin.send((json + "\n").encode())
        except anyio.ClosedResourceError:
            await anyio.lowlevel.checkpoint()

diff --git a/mcp_python/server/sse.py b/mcp_python/server/sse.py
@@ -74,7 +74,7 @@ async def sse_writer():
                    await sse_stream_writer.send(
                        {
                            "event": "message",
-                            "data": message.model_dump_json(by_alias=True),
+                            "data": message.model_dump_json(by_alias=True, exclude_none=True),
                        }
                    )


diff --git a/mcp_python/server/stdio.py b/mcp_python/server/stdio.py
@@ -48,7 +48,7 @@ async def stdout_writer():
        try:
            async with write_stream_reader:
                async for message in write_stream_reader:
-                    json = message.model_dump_json(by_alias=True)
+                    json = message.model_dump_json(by_alias=True, exclude_none=True)
                    await stdout.write(json + "\n")
                    await stdout.flush()
        except anyio.ClosedResourceError:

diff --git a/mcp_python/server/websocket.py b/mcp_python/server/websocket.py
@@ -47,7 +47,7 @@ async def ws_writer():
        try:
            async with write_stream_reader:
                async for message in write_stream_reader:
-                    obj = message.model_dump(by_alias=True, mode="json")
+                    obj = message.model_dump(by_alias=True, mode="json", exclude_none=True)
                    await websocket.send_json(obj)
        except anyio.ClosedResourceError:
            await websocket.close()

diff --git a/mcp_python/shared/session.py b/mcp_python/shared/session.py
@@ -132,7 +132,7 @@ async def send_request(
        self._response_streams[request_id] = response_stream

        jsonrpc_request = JSONRPCRequest(
-            jsonrpc="2.0", id=request_id, **request.model_dump(by_alias=True, mode="json")
+            jsonrpc="2.0", id=request_id, **request.model_dump(by_alias=True, mode="json", exclude_none=True)
        )

        # TODO: Support progress callbacks
@@ -150,7 +150,7 @@ async def send_notification(self, notification: SendNotificationT) -> None:
        Emits a notification, which is a one-way message that does not expect a response.
        """
        jsonrpc_notification = JSONRPCNotification(
-            jsonrpc="2.0", **notification.model_dump(by_alias=True, mode="json")
+            jsonrpc="2.0", **notification.model_dump(by_alias=True, mode="json", exclude_none=True)
        )

        await self._write_stream.send(JSONRPCMessage(jsonrpc_notification))
@@ -165,7 +165,7 @@ async def _send_response(
            jsonrpc_response = JSONRPCResponse(
                jsonrpc="2.0",
                id=request_id,
-                result=response.model_dump(by_alias=True, mode="json"),
+                result=response.model_dump(by_alias=True, mode="json", exclude_none=True),
            )
            await self._write_stream.send(JSONRPCMessage(jsonrpc_response))

@@ -180,7 +180,7 @@ async def _receive_loop(self) -> None:
                    await self._incoming_message_stream_writer.send(message)
                elif isinstance(message.root, JSONRPCRequest):
                    validated_request = self._receive_request_type.model_validate(
-                        message.root.model_dump(by_alias=True, mode="json")
+                        message.root.model_dump(by_alias=True, mode="json", exclude_none=True)
                    )
                    responder = RequestResponder(
                        request_id=message.root.id,
@@ -196,7 +196,7 @@ async def _receive_loop(self) -> None:
                        await self._incoming_message_stream_writer.send(responder)
                elif isinstance(message.root, JSONRPCNotification):
                    notification = self._receive_notification_type.model_validate(
-                        message.root.model_dump(by_alias=True, mode="json")
+                        message.root.model_dump(by_alias=True, mode="json", exclude_none=True)
                    )

                    await self._received_notification(notification)

diff --git a/tests/client/test_session.py b/tests/client/test_session.py
@@ -35,7 +35,7 @@ async def mock_server():
        jsonrpc_request = await client_to_server_receive.receive()
        assert isinstance(jsonrpc_request.root, JSONRPCRequest)
        request = ClientRequest.model_validate(
-            jsonrpc_request.model_dump(by_alias=True, mode="json")
+            jsonrpc_request.model_dump(by_alias=True, mode="json", exclude_none=True)
        )
        assert isinstance(request.root, InitializeRequest)

@@ -59,14 +59,14 @@ async def mock_server():
                    JSONRPCResponse(
                        jsonrpc="2.0",
                        id=jsonrpc_request.root.id,
-                        result=result.model_dump(by_alias=True, mode="json"),
+                        result=result.model_dump(by_alias=True, mode="json", exclude_none=True),
                    )
                )
            )
            jsonrpc_notification = await client_to_server_receive.receive()
            assert isinstance(jsonrpc_notification.root, JSONRPCNotification)
            initialized_notification = ClientNotification.model_validate(
-                jsonrpc_notification.model_dump(by_alias=True, mode="json")
+                jsonrpc_notification.model_dump(by_alias=True, mode="json", exclude_none=True)
            )

    async def listen_session():

diff --git a/tests/server/test_stdio.py b/tests/server/test_stdio.py
@@ -18,7 +18,7 @@ async def test_stdio_server():
    ]

    for message in messages:
-        stdin.write(message.model_dump_json() + "\n")
+        stdin.write(message.model_dump_json(by_alias=True, exclude_none=True) + "\n")
    stdin.seek(0)

    async with stdio_server(

diff --git a/tests/test_types.py b/tests/test_types.py
@@ -15,7 +15,7 @@ def test_jsonrpc_request():

    request = JSONRPCMessage.model_validate(json_data)
    assert isinstance(request.root, JSONRPCRequest)
-    ClientRequest.model_validate(request.model_dump(by_alias=True))
+    ClientRequest.model_validate(request.model_dump(by_alias=True, exclude_none=True))

    assert request.root.jsonrpc == "2.0"
    assert request.root.id == 1