fix: send initial SSE keepalive in /api/flow to flush response headers#251
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vivekchand wants to merge 1 commit intomainfrom
Open
fix: send initial SSE keepalive in /api/flow to flush response headers#251vivekchand wants to merge 1 commit intomainfrom
vivekchand wants to merge 1 commit intomainfrom
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…s immediately
The /api/flow SSE endpoint was hanging on initial connection because the
Flask/waitress server buffers the response until data is yielded. Added a
keepalive SSE comment as the first yield so HTTP headers are flushed
immediately, allowing E2E health checks to verify the endpoint returns 200.
This also improves client compatibility — EventSource clients now receive
the connection confirmation without waiting for the first real event.
Fixes E2E test failure: curl -w '%{http_code}' returned 000 (timeout) instead of 200.
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Problem
The
/api/flowSSE endpoint hangs on initial HTTP connection —curl -w '%{http_code}'returns000(timeout) instead of200, causing E2E health checks to fail.Root cause: Flask/waitress buffers the streaming response until actual data is yielded. Since
/api/flowonly yields events when new log activity occurs, a quiet dashboard causes HTTP headers to never flush, leaving clients stuck indefinitely.Fix
Add SSE comment (
: keepalive) as the very first yield ingenerate(). SSE comments are spec-valid and silently ignored by EventSource clients but force headers to flush immediately.Impact