stacklok / toolhive / 23235298350

64%

Build Type

push

github

Committed by web-flow

Commit Message

fix(vmcp): exempt SSE connections from WriteTimeout to prevent drops (#4167)

fix(vmcp): remove WriteTimeout to prevent SSE connection drops

Go's http.Server.WriteTimeout sets an absolute deadline on the entire
response duration. For long-lived SSE connections used by the MCP
Streamable HTTP transport, this caused streams to be killed after 30s
regardless of write activity (see golang/go#16100).

Remove WriteTimeout from the http.Server config and replace it with a
writeTimeoutMiddleware that uses http.ResponseController.SetWriteDeadline
to apply a per-request 30s write deadline only to non-GET (non-SSE)
requests. GET requests remain exempt so SSE streams can stay open
indefinitely.

Tests added:
- Unit tests verifying SetWriteDeadline is called/not called by method
- Integration test over a real TCP connection confirming an SSE stream
  survives past the timeout without being cut

Fixes #3691

Co-authored-by: taskbot <taskbot@users.noreply.github.com>

Run Details

23 of 23 new or added lines in 2 files covered. (100.0%)

254 existing lines in 5 files now uncovered.

49402 of 76484 relevant lines covered (64.59%)

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