fix(ENGEN-3331): prevent handler deadlock on credentials channel in listener mode#372
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upvest-mike merged 3 commits intoupvestco:mainfrom Mar 11, 2026
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What
Replace blocking channel send with non-blocking select in handler.go when forwarding credentials to the webhook tunnel system.
Why
When running with -l, the proxy sends user credentials to
Tunnels.Start()via an unbuffered channel after each/auth/tokenrequest. IfTunnelIsReady()fails during tunnel startup,Start()returns early and nobody reads from the channel. The next/auth/tokenrequest blocks forever on the channel send, deadlocking the handler goroutine - even though the HTTP response has already been written.The non-blocking select drops the credentials when no reader is available, which is correct since the response is already sent and the tunnel system is not running.