fix(recorder): stream SSE responses instead of buffering (v1.14.5)#125
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`proxyAndRecord` collected every upstream chunk into an array and replayed the entire body via a single `res.end()` at the bottom of the function. For `text/event-stream` responses this collapses all frames into one client-visible write, defeating progressive rendering in downstream consumers. When upstream declares `content-type: text/event-stream`, tee each incoming chunk to the client while still accumulating into the recording buffer. Non-SSE responses continue to use the existing buffered relay path unchanged. Latent since v1.6.0 (`900399b`); surfaced in production once showcase traffic began exercising `--proxy-only` more heavily under tightened v1.14.0+ fixture handling.
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) ## Summary - `proxyAndRecord` buffered upstream SSE bodies and replayed in a single `res.end()`, collapsing chunks into one client-visible write. - Showcase's `--proxy-only` mode hit this path in production, breaking progressive streaming downstream. - Surgical split: when upstream `content-type` is `text/event-stream`, relay chunks to the client as they arrive while still tee-ing into the recording buffer. Non-SSE behavior unchanged. ## Context Latent since v1.6.0 (`900399b`). Exposed in production after v1.14.0+ fixture handling tightened and more showcase traffic began hitting the proxy path. Live curl against deployed `showcase-aimock-production` confirmed: 11 SSE frames in 35µs after a 515ms TTFB — classic buffer-and-replay signature. ## Test plan - [x] Full aimock suite green (2436 passing) - [x] Build green - [x] New `recorder SSE progressive streaming` test — red on pre-fix recorder (single data event, `arrivalTimes.length === 1`), green after fix (multi-frame span >=100ms) - [ ] Post-release: showcase `:latest` auto-picks up; Jordan verifies via Playwright probe
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Summary
proxyAndRecordbuffered upstream SSE bodies and replayed in a singleres.end(), collapsing chunks into one client-visible write.--proxy-onlymode hit this path in production, breaking progressive streaming downstream.content-typeistext/event-stream, relay chunks to the client as they arrive while still tee-ing into the recording buffer. Non-SSE behavior unchanged.Context
Latent since v1.6.0 (
900399b). Exposed in production after v1.14.0+ fixture handling tightened and more showcase traffic began hitting the proxy path.Live curl against deployed
showcase-aimock-productionconfirmed: 11 SSE frames in 35µs after a 515ms TTFB — classic buffer-and-replay signature.Test plan
recorder SSE progressive streamingtest — red on pre-fix recorder (single data event,arrivalTimes.length === 1), green after fix (multi-frame span >=100ms):latestauto-picks up; Jordan verifies via Playwright probe