Ensure FastMCP lifespan uses async context manager #58
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Pull Request Overview
This PR fixes a FastMCP lifespan issue where SSE connections were crashing due to improper async context manager usage. The fix wraps the PlexServer's lifespan hook in an asynccontextmanager decorator to ensure proper cleanup under HTTP transports.
- Converts the plain async generator to an async context manager with try/finally structure
- Adds a regression test to verify the server lifespan functionality works correctly
- Updates package version to 0.26.26
Reviewed Changes
Copilot reviewed 3 out of 4 changed files in this pull request and generated 1 comment.
| File | Description |
|---|---|
| mcp_plex/server.py | Adds asynccontextmanager decorator and try/finally structure to lifespan hook |
| tests/test_server.py | Adds regression test for server lifespan context manager functionality |
| pyproject.toml | Bumps version from 0.26.25 to 0.26.26 |
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| try: | ||
| yield | ||
| finally: | ||
| await self.close() |
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The try/finally block is redundant here. Since asynccontextmanager already handles exceptions and ensures cleanup code runs, the bare try/yield/finally pattern doesn't add value and can be simplified to just yield followed by await self.close().
| try: | |
| yield | |
| finally: | |
| await self.close() | |
| yield | |
| await self.close() |
What
PlexServer's FastMCP lifespan hook in anasynccontextmanagerso cleanup runs under HTTP transportsuv.lockWhy
Affects
Testing
uv run ruff check .uv run pytestDocumentation
https://chatgpt.com/codex/tasks/task_e_68d27e285d44832880c41fef310052b2