Files
modelcontextprotocol--pytho…/tests/shared/test_progress_notifications.py
2026-02-02 13:24:55 +01:00

403 lines
15 KiB
Python

from typing import Any, cast
from unittest.mock import patch
import anyio
import pytest
import mcp.types as types
from mcp import Client
from mcp.client.session import ClientSession
from mcp.server import Server
from mcp.server.lowlevel import NotificationOptions
from mcp.server.models import InitializationOptions
from mcp.server.session import ServerSession
from mcp.shared.context import RequestContext
from mcp.shared.message import SessionMessage
from mcp.shared.progress import progress
from mcp.shared.session import BaseSession, RequestResponder
@pytest.mark.anyio
async def test_bidirectional_progress_notifications():
"""Test that both client and server can send progress notifications."""
# Create memory streams for client/server
server_to_client_send, server_to_client_receive = anyio.create_memory_object_stream[SessionMessage](5)
client_to_server_send, client_to_server_receive = anyio.create_memory_object_stream[SessionMessage](5)
# Track progress updates
server_progress_updates: list[dict[str, Any]] = []
client_progress_updates: list[dict[str, Any]] = []
# Progress tokens
server_progress_token = "server_token_123"
client_progress_token = "client_token_456"
# Store server session reference
serv_sesh: ServerSession | None = None
# Define handlers
async def on_progress_notification(notification: types.ProgressNotification) -> None:
params = notification.params
server_progress_updates.append(
{
"token": params.progress_token,
"progress": params.progress,
"total": params.total,
"message": params.message,
}
)
async def on_list_tools(
ctx: RequestContext[ServerSession, Any, Any],
params: types.PaginatedRequestParams | None,
) -> types.ListToolsResult:
return types.ListToolsResult(
tools=[
types.Tool(
name="test_tool",
description="A tool that sends progress notifications <o/",
input_schema={},
)
]
)
async def on_call_tool(
ctx: RequestContext[ServerSession, Any, Any],
params: types.CallToolRequestParams,
) -> types.CallToolResult:
nonlocal serv_sesh
name = params.name
arguments = params.arguments
# Make sure we received a progress token
if name == "test_tool":
if arguments and "_meta" in arguments:
progressToken = arguments["_meta"]["progressToken"]
if not progressToken: # pragma: no cover
raise ValueError("Empty progress token received")
if progressToken != client_progress_token: # pragma: no cover
raise ValueError("Server sending back incorrect progressToken")
assert serv_sesh is not None
# Send progress notifications
await serv_sesh.send_progress_notification(
progress_token=progressToken,
progress=0.25,
total=1.0,
message="Server progress 25%",
)
await serv_sesh.send_progress_notification(
progress_token=progressToken,
progress=0.5,
total=1.0,
message="Server progress 50%",
)
await serv_sesh.send_progress_notification(
progress_token=progressToken,
progress=1.0,
total=1.0,
message="Server progress 100%",
)
else: # pragma: no cover
raise ValueError("Progress token not sent.")
return types.CallToolResult(content=[types.TextContent(type="text", text="Tool executed successfully")])
raise ValueError(f"Unknown tool: {name}") # pragma: no cover
# Create a server with progress capability
server = Server(
name="ProgressTestServer",
on_list_tools=on_list_tools,
on_call_tool=on_call_tool,
on_progress_notification=on_progress_notification,
)
# Run a server session so we can send progress updates in tool
async def run_server():
nonlocal serv_sesh
# Create a server session
async with ServerSession(
client_to_server_receive,
server_to_client_send,
InitializationOptions(
server_name="ProgressTestServer",
server_version="0.1.0",
capabilities=server.get_capabilities(NotificationOptions(), {}),
),
) as server_session:
serv_sesh = server_session
async for message in server_session.incoming_messages:
try:
await server._handle_message(message, server_session, {})
except Exception as e: # pragma: no cover
raise e
# Client message handler to store progress notifications
async def handle_client_message(
message: RequestResponder[types.ServerRequest, types.ClientResult] | types.ServerNotification | Exception,
) -> None:
if isinstance(message, Exception): # pragma: no cover
raise message
if isinstance(message, types.ServerNotification): # pragma: no branch
if isinstance(message, types.ProgressNotification): # pragma: no branch
params = message.params
client_progress_updates.append(
{
"token": params.progress_token,
"progress": params.progress,
"total": params.total,
"message": params.message,
}
)
# Test using client
async with (
ClientSession(
server_to_client_receive,
client_to_server_send,
message_handler=handle_client_message,
) as client_session,
anyio.create_task_group() as tg,
):
# Start the server in a background task
tg.start_soon(run_server)
# Initialize the client connection
await client_session.initialize()
# Call list_tools with progress token
await client_session.list_tools()
# Call test_tool with progress token
await client_session.call_tool("test_tool", {"_meta": {"progressToken": client_progress_token}})
# Send progress notifications from client to server
await client_session.send_progress_notification(
progress_token=server_progress_token,
progress=0.33,
total=1.0,
message="Client progress 33%",
)
await client_session.send_progress_notification(
progress_token=server_progress_token,
progress=0.66,
total=1.0,
message="Client progress 66%",
)
await client_session.send_progress_notification(
progress_token=server_progress_token,
progress=1.0,
total=1.0,
message="Client progress 100%",
)
# Wait and exit
await anyio.sleep(0.5)
tg.cancel_scope.cancel()
# Verify client received progress updates from server
assert len(client_progress_updates) == 3
assert client_progress_updates[0]["token"] == client_progress_token
assert client_progress_updates[0]["progress"] == 0.25
assert client_progress_updates[0]["message"] == "Server progress 25%"
assert client_progress_updates[2]["progress"] == 1.0
# Verify server received progress updates from client
assert len(server_progress_updates) == 3
assert server_progress_updates[0]["token"] == server_progress_token
assert server_progress_updates[0]["progress"] == 0.33
assert server_progress_updates[0]["message"] == "Client progress 33%"
assert server_progress_updates[2]["progress"] == 1.0
@pytest.mark.anyio
async def test_progress_context_manager():
"""Test client using progress context manager for sending progress notifications."""
# Create memory streams for client/server
server_to_client_send, server_to_client_receive = anyio.create_memory_object_stream[SessionMessage](5)
client_to_server_send, client_to_server_receive = anyio.create_memory_object_stream[SessionMessage](5)
# Track progress updates
server_progress_updates: list[dict[str, Any]] = []
progress_token = None
# Register progress handler
async def on_progress_notification(notification: types.ProgressNotification) -> None:
params = notification.params
server_progress_updates.append(
{
"token": params.progress_token,
"progress": params.progress,
"total": params.total,
"message": params.message,
}
)
server = Server(name="ProgressContextTestServer", on_progress_notification=on_progress_notification)
# Run server session to receive progress updates
async def run_server():
# Create a server session
async with ServerSession(
client_to_server_receive,
server_to_client_send,
InitializationOptions(
server_name="ProgressContextTestServer",
server_version="0.1.0",
capabilities=server.get_capabilities(NotificationOptions(), {}),
),
) as server_session:
async for message in server_session.incoming_messages:
try:
await server._handle_message(message, server_session, {})
except Exception as e: # pragma: no cover
raise e
# Client message handler
async def handle_client_message(
message: RequestResponder[types.ServerRequest, types.ClientResult] | types.ServerNotification | Exception,
) -> None:
if isinstance(message, Exception): # pragma: no cover
raise message
# run client session
async with (
ClientSession(
server_to_client_receive,
client_to_server_send,
message_handler=handle_client_message,
) as client_session,
anyio.create_task_group() as tg,
):
tg.start_soon(run_server)
await client_session.initialize()
progress_token = "client_token_456"
# Create request context
request_context = RequestContext(
request_id="test-request",
session=client_session,
meta={"progress_token": progress_token},
lifespan_context=None,
)
# cast for type checker
typed_context = cast(RequestContext[BaseSession[Any, Any, Any, Any, Any], Any], request_context)
# Utilize progress context manager
with progress(typed_context, total=100) as p:
await p.progress(10, message="Loading configuration...")
await p.progress(30, message="Connecting to database...")
await p.progress(40, message="Fetching data...")
await p.progress(20, message="Processing results...")
# Wait for all messages to be processed
await anyio.sleep(0.5)
tg.cancel_scope.cancel()
# Verify progress updates were received by server
assert len(server_progress_updates) == 4
# first update
assert server_progress_updates[0]["token"] == progress_token
assert server_progress_updates[0]["progress"] == 10
assert server_progress_updates[0]["total"] == 100
assert server_progress_updates[0]["message"] == "Loading configuration..."
# second update
assert server_progress_updates[1]["token"] == progress_token
assert server_progress_updates[1]["progress"] == 40
assert server_progress_updates[1]["total"] == 100
assert server_progress_updates[1]["message"] == "Connecting to database..."
# third update
assert server_progress_updates[2]["token"] == progress_token
assert server_progress_updates[2]["progress"] == 80
assert server_progress_updates[2]["total"] == 100
assert server_progress_updates[2]["message"] == "Fetching data..."
# final update
assert server_progress_updates[3]["token"] == progress_token
assert server_progress_updates[3]["progress"] == 100
assert server_progress_updates[3]["total"] == 100
assert server_progress_updates[3]["message"] == "Processing results..."
@pytest.mark.anyio
async def test_progress_callback_exception_logging():
"""Test that exceptions in progress callbacks are logged and \
don't crash the session."""
# Track logged warnings
logged_errors: list[str] = []
def mock_log_exception(msg: str, *args: Any, **kwargs: Any) -> None:
logged_errors.append(msg % args if args else msg)
# Create a progress callback that raises an exception
async def failing_progress_callback(progress: float, total: float | None, message: str | None) -> None:
raise ValueError("Progress callback failed!")
async def on_call_tool(
ctx: RequestContext[ServerSession, Any, Any],
params: types.CallToolRequestParams,
) -> types.CallToolResult:
name = params.name
if name == "progress_tool":
# Send a progress notification
await ctx.session.send_progress_notification(
progress_token=ctx.request_id,
progress=50.0,
total=100.0,
message="Halfway done",
)
return types.CallToolResult(content=[types.TextContent(type="text", text="progress_result")])
raise ValueError(f"Unknown tool: {name}") # pragma: no cover
async def on_list_tools(
ctx: RequestContext[ServerSession, Any, Any],
params: types.PaginatedRequestParams | None,
) -> types.ListToolsResult:
return types.ListToolsResult(
tools=[
types.Tool(
name="progress_tool",
description="A tool that sends progress notifications",
input_schema={},
)
]
)
# Create a server with a tool that sends progress notifications
server = Server(name="TestProgressServer", on_list_tools=on_list_tools, on_call_tool=on_call_tool)
# Test with mocked logging
with patch("mcp.shared.session.logging.exception", side_effect=mock_log_exception):
async with Client(server) as client:
# Call tool with a failing progress callback
result = await client.call_tool(
"progress_tool",
arguments={},
progress_callback=failing_progress_callback,
)
# Verify the request completed successfully despite the callback failure
assert len(result.content) == 1
content = result.content[0]
assert isinstance(content, types.TextContent)
assert content.text == "progress_result"
# Check that a warning was logged for the progress callback exception
assert len(logged_errors) > 0
assert any("Progress callback raised an exception" in warning for warning in logged_errors)