* feat(v3): content-dependent playlist covers + custom art upload
Playlist cards were a tiny 🎵 emoji on an empty square. Now the cover reflects
the playlist's contents, and you can override it with a custom image.
Cover (in priority order):
- custom uploaded cover, else
- empty playlist -> the icon
- a few songs -> the first song's album art
- 4+ songs -> a 2x2 album-art mosaic
Backend (server.py):
- MetadataDB.list_playlists() returns each playlist's first few still-present
songs' art URLs (`art_urls`) for the content cover.
- GET /api/playlists and GET /api/playlists/{id} add `cover_url` when a custom
cover exists.
- POST/GET/DELETE /api/playlists/{id}/cover — store a small PNG thumbnail under
CONFIG_DIR/playlist_covers/ (PIL-converted, mirroring song-art upload); the
cover is deleted with the playlist. Cover mutators added to _MUTATING_ROUTES.
Frontend (static/v3/playlists.js): playlistCoverHtml(p) renders the rules above;
the playlist detail view gets "Cover" (pick an image) + "Remove cover".
Tests: tests/test_playlists_api.py (art_urls + cover roundtrip / reject-non-image
/ delete-removes-cover — 11 pass) and tests/js/v3_playlist_cover.test.js.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QbexxfTt8q2tAn436MqGWF
* fix(playlists): 400 (not 500) on non-string cover image + bust same-second cover cache
Two review follow-ups on the playlist-cover endpoints:
- POST /cover did `if "," in b64` before any type check, so a non-string
image (e.g. {"image": 123} / null) raised TypeError -> 500. Guard with
isinstance (mirrors the avatar/song-art upload) for a clean 400. +regression
test covering number/null/object/list.
- The cover URL busted only on int(st_mtime) (1s granularity) and GET /cover
sent no cache headers, so a same-second replace/remove/re-upload could serve
a stale image. Use st_mtime_ns in the cache-bust token and add the shared
no-cache header (_ART_CACHE_HEADERS), matching song art.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Co-authored-by: byrongamatos <xasiklas@gmail.com>
