feat: log warning when SSE flush to client is slow#269
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Mostly looks good, but this log isn't actionable right now.
Adds slow client detection to the EventStream SSE sender. After each flush, the elapsed time is measured using an injected quartz.Clock. If it exceeds 500ms, a Warn log is emitted with the flush duration, making slow clients immediately visible in logs without requiring distributed tracing infrastructure. quartz.Clock is injected into EventStream so tests can simulate slow flushes by advancing a mock clock — no real sleeping required.
Apply reviewer feedback:
- Replace custom captureSink with sloghuman.Sink(&strings.Builder{})
- Use exported SlowFlushThreshold constant instead of hardcoded 600ms
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dannykopping
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dannykopping
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LGTM, just one nit
I don't need to review again
Thanks a lot @mtojek!
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Fixes: #66
Adds slow client detection to the EventStream SSE sender. After each flush, the elapsed time is measured using an injected quartz.Clock. If it exceeds 500ms, a Warn log is emitted with the flush duration, making slow clients immediately visible in logs without requiring distributed tracing infrastructure.
quartz.Clock is injected into EventStream so tests can simulate slow flushes by advancing a mock clock — no real sleeping required.