fix: Clean up sessions from manager when terminated via DELETE request #791
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Previously, StreamableHTTPSessionManager would not remove sessions from its _server_instances dictionary when clients sent DELETE requests to terminate sessions. This caused terminated sessions to remain in memory until server shutdown, leading to potential memory accumulation in long-running servers. This change adds a callback mechanism between StreamableHTTPServerTransport and StreamableHTTPSessionManager to properly clean up terminated sessions: - Add on_session_terminated callback parameter to StreamableHTTPServerTransport - Implement _on_session_terminated method in StreamableHTTPSessionManager - Call callback from _terminate_session when DELETE request terminates session - Update HTTP status codes: return 404 NOT_FOUND for unknown session IDs - Add comprehensive test to verify session cleanup functionality Sessions are now automatically removed from the manager's memory when explicitly terminated via DELETE requests, preventing memory leaks while maintaining backward compatibility. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <[email protected]>
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Jul 29, 2025
…-mcp-client Docs: Add Memex to clients.mdx
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Summary
This PR fixes a memory leak issue in
StreamableHTTPSessionManagerwhere sessions were not being cleaned up from the manager's internal dictionary when terminated via DELETE requests.Problem
Previously, when clients sent DELETE requests to terminate sessions:
StreamableHTTPServerTransportwould mark itself as terminatedStreamableHTTPSessionManagerwould continue to hold references to these terminated sessions in its_server_instancesdictionarySolution
Added a callback mechanism to properly clean up terminated sessions:
StreamableHTTPServerTransportconstructor (on_session_terminated)StreamableHTTPSessionManager(_on_session_terminated)Technical Details
StreamableHTTPServerTransport._terminate_session()now calls the callbackStreamableHTTPSessionManager._server_instancesTest Plan
test_session_cleanup_on_delete_requestBackward Compatibility
✅ This change is fully backward compatible - no breaking changes to existing APIs.
Generated with Claude Code