Handle exceptions during draining pending calls / streams#12737
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kannanjgithub wants to merge 5 commits intogrpc:masterfrom
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Handle exceptions during draining pending calls / streams#12737kannanjgithub wants to merge 5 commits intogrpc:masterfrom
kannanjgithub wants to merge 5 commits intogrpc:masterfrom
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…handled framing exception during the draining of DelayedStream. When MessageFramer throws an exception (e.g., RESOURCE_EXHAUSTED), it bubbles up through DelayedStream.drainPendingCalls and is eventually caught and swallowed by ThreadlessExecutor.runQuietly. This leaves the DelayedStream in an inconsistent state (where passThrough is still false), and the responseFuture never completes, causing the blocking call to hang forever. I have implemented a fix that adds proper exception handling to the draining loops in both DelayedStream and DelayedClientCall. When an exception occurs during draining: 1. The realStream (or realCall) is explicitly cancelled with the error. 2. The pending calls are cleared. 3. The stream/call transitions to passThrough = true to prevent getting stuck. 4. The listener's pending callbacks are drained, ensuring that any closure notifications are delivered to the application.
…Stream and DelayedClientCall
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The reported hang in issue #12109 in
blockingUnaryCallwas caused by an unhandled framing exception during the draining ofDelayedStream. WhenMessageFramerthrows anexception (e.g., RESOURCE_EXHAUSTED), it bubbles up through
DelayedStream.drainPendingCallsand is eventually caught and swallowed byThreadlessExecutor.runQuietly. This leaves theDelayedStreamin an inconsistent state (where passThrough is still false), and theresponseFuturenever completes, causing the blocking call to hang forever.This fix adds proper exception handling to the draining loops in both
DelayedStreamandDelayedClientCall. When an exception occurs during draining: