fix(server): send SSE-friendly headers on /hyper/events#35
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Prevent reverse proxies such as NGINX and OpenResty from buffering or transforming Hyper's SSE stream. In some managed hosting setups, that can delay SSE patches and leave the UI stuck in transient states even though the underlying action has already completed. Send Cache-Control: no-cache, no-transform and X-Accel-Buffering: no with Hyper's built-in /hyper/events response so SSE behaves reliably behind those proxies while preserving the existing Brotli behavior.
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Closes dynamic-alpha#35 Prevent reverse proxies such as NGINX and OpenResty from buffering or transforming Hyper's SSE stream. In some managed hosting setups, that can delay SSE patches and leave the UI stuck in transient states even though the underlying action has already completed. Send Cache-Control: no-cache, no-transform and X-Accel-Buffering: no with Hyper's built-in /hyper/events response so SSE behaves reliably behind those proxies while preserving the existing Brotli behavior. (cherry picked from commit f49074c) # Conflicts: # src/hyper/server.clj
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Summary
Add SSE-friendly response headers to Hyper's built-in
/hyper/eventsendpoint:
Cache-Control: no-cache, no-transformX-Accel-Buffering: noWhy
Some Hyper deployments sit behind reverse proxies such as NGINX or
OpenResty. Those proxies can buffer or transform
text/event-streamresponses, which delays SSE delivery and can leave the browser UI stuck
in transient states even though the server-side action has already
completed.
These headers improved that behaviour in a managed hosting deployment
without requiring app-specific configuration or disabling Brotli.
Notes
Cache-Control: no-cache, no-transformis appropriate for a live SSE stream.X-Accel-Buffering: nois useful for NGINX/OpenResty and is generally harmless elsewhere.Content-TypeandContent-Encodingremain under Hyper's control.Testing
Add a focused test covering the initial SSE response headers with and
without Brotli compression.