Aias00 opened a new pull request, #3531:
URL: https://github.com/apache/dubbo-go/pull/3531
## What
`ExchangeClient.AsyncRequest` leaked a `PendingResponse` and never invoked
the `AsyncCallback` when no reply arrived (e.g. the connection dropped before
the server responded).
## Why
```go
// remoting/exchange_client.go AsyncRequest (before)
rsp := NewPendingResponse(request.ID)
rsp.Callback = callback
AddPendingResponse(rsp)
err := client.client.Request(request, timeout, rsp)
if err != nil {
RemovePendingResponse(SequenceType(request.ID)) // only the
write-error path cleans up
result.Err = err
return err
}
result.Rest = rsp.response
return nil // no timeout enforcement; no removal/callback on no-reply
```
The async path returns immediately (getty returns immediately for callback
requests, so the `timeout` argument was ignored). The only removal sites are
`Response.Handle` (on reply) and the write-error branch. If the write succeeds
and the connection drops before the server replies, `getty`'s
`removeSession`/`close` never fail the in-flight `pendingResponses`, so the
entry leaks in the global `sync.Map` and the `AsyncCallback` never fires — the
caller hangs. Distinct from #3440 (write-error-path cleanup); this is the
no-reply / connection-drop path.
## Fix
After a successful `client.client.Request`, install `time.AfterFunc(timeout,
...)` that calls `RemovePendingResponse(seq)`. If it returns non-nil (reply has
not arrived), invoke `pr.Callback(pr.GetCallResponse())` with a timeout error.
`RemovePendingResponse` is an atomic load-and-delete (`sync.Map`), so the timer
and the reply path (`Response.Handle`) cannot both win the pending —
exactly-once callback. `timeout == 0` preserves the previous wait-forever
behavior.
## Tests
Added `TestExchangeClientAsyncRequestTimeoutCallback`: a mock client whose
`Request` succeeds and never delivers a reply (simulating connection drop);
asserts the `AsyncCallback` fires with a timeout error and the global map does
not leak. `remoting` package passes under `-race`.
Fixes #3530
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
