[rcooney-sh]

Summary

Follow-up to #65. The recovery interceptors added there only cover the handler goroutine. ByteStream/Write hands the body to putUpload on its own goroutine via an io.Pipe, and for compressed uploads that is where the zstd decoder runs, so a panic there still exited the process.

Recover in the put goroutine

go func() {
    defer s.releaseCASWriteSlot()
    defer func() {
        if r := recover(); r != nil {
            _ = pr.CloseWithError(errPutPanicked)
            putResult <- recoveredPanicStatus("ByteStream/Write put", r)
        }
    }()
    putResult <- s.putUpload(srv.Context(), hash, size, cmp, pr)
}()

The write fails with codes.Internal, the pipe is closed so the recv loop unblocks, and the CAS write slot is still released.

Test

TestGrpcByteStreamWritePutPanicFailsOnlyThatWrite wraps the disk cache so Put panics, sends a write, expects Internal, and checks the server still answers GetCapabilities. Without the recover it crashes the test binary.

Worth including in v2.6.1-blacksmith.14 if it hasn't been cut yet; otherwise it can ride the next tag, since the klauspost bump in #65 is the actual fix.

Link to Devin session: https://app.devin.ai/sessions/c4fbdf7fdaee45c89654f8496af5720b
Open in Devin Desktop: https://app.devin.ai/desktop/session/c4fbdf7fdaee45c89654f8496af5720b?variant=devin
Requested by: @rcooney-sh

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[devin-ai-integration]

I'll fix CI failures and address comments from users with write access. I'll skip comments containing "(aside)".

• Disable automatic comment, CI, and merge conflict monitoring

[blacksmith-staging]

Put panic fails one write, server survives

Before, the panicking zstd upload killed the server and every later call was refused. After, only that write failed with Internal, and later calls and writes still succeeded.

_Merge-base

_{This PR c2c6630b}

Also checked · 1 match

CAS write slot released after panic

_{Proof on c2c6630b}

View full Proof report