fix: close per-request server and transport in example-apps handler#42
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fix: close per-request server and transport in example-apps handler#42
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The stateless /:slug/mcp handler creates a fresh McpServer and StreamableHTTPServerTransport on every request but never closed them, leaking memory under load. Register a 'close' listener (fires on both normal completion and client abort mid-SSE) to release them.
pja-ant
approved these changes
Apr 23, 2026
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Summary
/:slug/mcphandler insrc/modules/example-apps/index.tscreates a freshMcpServer+StreamableHTTPServerTransporton every request but never closes either, so they accumulate until GC pressure stalls the process under sustained load.res.on('close', ...)to close both. Using'close'(rather than'finish') ensures cleanup also runs when the client aborts mid-SSE-stream.Follow-up
src/modules/mcp/handlers/shttp.tsusesres.on('finish', ...)for its cleanup, which does not fire on client abort. May warrant the same'close'treatment in a separate PR.Test plan
npm run buildnpm run lintnpm test(79/79)