Move END_STREAM check earlier. #237
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Motivation: In an earlier patch (1e68e51) we attempted to avoid emitting WINDOW_UPDATE frames on streams that were already closed on their inbound side. This was largely a reasonable fix, but we missed an important area: END_STREAM in a sequence of frames. This would be triggered if we received multiple DATA frames in a row, where the last one contained END_STREAM but an earlier one triggered a WINDOW_UPDATE. The stream state machine would have seen the END_STREAM already and will forbid the WINDOW_UPDATE, but the stream channel won't yet have seen it and will try to send it. The fix is easy enough: look for END_STREAM earlier. Modifications: - Check for END_STREAM when the stream channel receives the frame, not when it passes it into the pipeline. Result: Fewer spurious connection errors.
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@swift-nio-bot test this please |
Davidde94
approved these changes
Sep 9, 2020
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Motivation:
In an earlier patch (1e68e51) we attempted to avoid emitting
WINDOW_UPDATE frames on streams that were already closed on their
inbound side. This was largely a reasonable fix, but we missed an
important area: END_STREAM in a sequence of frames.
This would be triggered if we received multiple DATA frames in a row,
where the last one contained END_STREAM but an earlier one triggered a
WINDOW_UPDATE. The stream state machine would have seen the END_STREAM
already and will forbid the WINDOW_UPDATE, but the stream channel won't
yet have seen it and will try to send it.
The fix is easy enough: look for END_STREAM earlier.
Modifications:
when it passes it into the pipeline.
Result:
Fewer spurious connection errors.