YouTube content stores thumbnail_path as a REMOTE URL
(https://img.youtube.com/vi/<id>/hqdefault.jpg), but the thumbnail-serving route
path.resolve'd it into contentDir -> a local file that never existed -> ENOENT logged
a few times a minute (the tester-log spam). Recreating content didn't help (new rows
store the same remote URL).
- GET /api/content/:id/thumbnail now proxies a remote http(s) thumbnail_path
server-side (same-origin, so dashboard CSP img-src is unaffected) via a non-throwing
helper: upstream 404 -> 404, other failure/timeout -> 502, image/* only (modest SSRF
hardening; the URL is server-set at ingest). Local thumbnails keep the sendFile path;
the playlist/widget/workspace access gating is unchanged for both branches.
- routes/widgets.js inlineUserContent skips the disk read for a remote thumbnail and
leaves the /api/content/:id/thumbnail reference in place (the proxy serves it).
- routes/content.js ingest unchanged; a comment notes the future download-at-ingest +
backfill option for CDN independence.
- New test/thumbnail-proxy.test.js: local sendFile still works; a remote thumbnail is
proxied (mock upstream, no local read, no ENOENT); upstream 404 -> clean 404. Full
server suite 164/164.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
