Multi-artist surfaces (home Rediscover, Library Artists tab, Liked
Artists carousel) were all rendering the music-notes placeholder
instead of real artist covers. Root cause:
CachedArtist.toRef() returned an ArtistRef with empty coverUrl —
the cache doesn't store the representative album id the server
derives at query time, and the adapter never reconstructed it.
The artist detail screen worked coincidentally because it derives
its header cover from `artist.albums[0].id` directly rather than
the ArtistRef's coverUrl field.
Fix:
* CachedArtistAdapter.toRef() now accepts an optional coverAlbumId
and reconstructs `/api/albums/<id>/cover` when given. Matches the
pattern AlbumRef uses (deterministic URL from entity id).
* artistTileProvider, libraryArtistsProvider, and artistProvider
(single-artist) each LEFT JOIN cached_albums ordered by sort_title.
First row per artist carries the alphabetically-first album id;
toRef projects that into the cover URL.
* Multi-artist queries dedup in toResult since the join multiplies
rows by album count.
Artists with no albums yet in drift come through with empty
coverUrl — UI falls back to the music-notes placeholder, same
behavior as before for that legitimately-coverless state.
Same fix shape as albums: drift's CachedPlaylistAdapter.toRef was
returning coverUrl: '' because the cache table doesn't persist the
server-derived URL. Set it to /api/playlists/<id>/cover in the
adapter — handleGetPlaylistCover serves the cached collage from
disk, so the URL is deterministic and the round-trip through drift
no longer drops it.
PlaylistCard + PlaylistsListScreen pass the existing queue_music
icon as ServerImage's fallback, so when the server hasn't built a
collage yet (system playlists with no tracks at build time), the
endpoint 404s and the icon shows over the slate background instead
of an empty box.
Drift cache intentionally drops cover_url (server-derived). The
adapters comment says "REST cold-cache fallback briefly shows the real
values before drift takes over" — but once drift takes over, covers
are empty forever. Fix per source:
- Album cover: server constructs the URL deterministically as
/api/albums/<id>/cover (internal/api/convert.go:69). Mirror that
in CachedAlbumAdapter.toRef so AlbumRef.coverUrl is non-empty
whether the row came from a fresh fetch or a drift hit. Restores
cover art on the artist detail album grid (and any other surface
reading albums from drift).
- Artist cover: server picks a representative album and reuses its
cover (convert.go:98). Drift doesn't store the pointer, so derive
client-side via the artist's first loaded album. New _ArtistAvatar
prefers a non-empty server-emitted coverUrl and falls back to
/api/albums/<firstAlbumId>/cover, then slate while the album list
is still loading.
Album grid spacing was off because childAspectRatio: 0.8 inflated
each cell taller than the AlbumCard's actual ~160dp footprint,
leaving a visible gap below every card. Switch to mainAxisExtent: 168
with explicit 8dp main/cross spacing — cells now match the card and
sit on a clean grid.
Two fixes in one commit because they're entangled — the systemVariant
work would have been theater otherwise.
## The wire-format bug
/api/library/sync was emitting PascalCase JSON for artist / album /
track / playlist upserts (raw json.Marshal of sqlc-generated structs
with no JSON tags — sqlc.yaml: emit_json_tags=false). Flutter's
sync_controller _*FromJson reads snake_case keys, so all metadata
sync rows landed in drift with empty strings / zero ints.
The like_track / like_album / like_artist / playlist_track entities
work because they're hand-built `map[string]string` payloads with
snake_case keys — they sidestepped the bug. The 4 raw-marshal
entities did not.
Existing sync test caught zero of this — it asserts on len(upserts)
not field shape.
Fix: server-side view structs in library_sync_views.go with proper
JSON tags + pgtype-flattening (UUID → 8-4-4-4-12 hex string,
Date → "2006-01-02"). Mirrors the playlistRowView pattern from
/api/playlists. New library_sync_views_test.go pins the wire keys
so future field-name drift breaks loud.
## systemVariant column (closes#357 plan C v1 limitation)
playlistSyncView now carries `system_variant` server → wire.
Flutter drift schema bumped from 1 → 2 with onUpgrade adding the
`systemVariant TEXT NULL` column to cached_playlists. Cursor reset
to 0 in the migration so existing rows refresh with the new field
on the next sync.
playlistsListProvider now filters locally by systemVariant:
- kind='user' → systemVariant IS NULL (the add-to-playlist sheet's intent)
- kind='system' → systemVariant IS NOT NULL
- kind='all' → no filter
Closes the documented v1 limitation where the add-to-playlist sheet
showed system playlists alongside user-created ones.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Foundation for the provider migrations. cacheFirst<D, T> wraps the
drift.watch() + REST cold-cache fallback pattern: yields cached rows
when present, kicks off REST fetch + drift populate when empty +
online, yields empty when offline. REST failures swallow to empty so
callers can surface errors via toast.
adapters.dart adds CachedX → XRef extension methods + reverse
XRef.toDrift() companions for Artist/Album/Track/Playlist. Adapters
accept some loss of server-derived fields (coverUrl, streamUrl,
ownerUsername) — UI already handles empty values; cold-cache fallback
briefly shows the real values before drift takes over.
cache_first_test covers all 4 branches (non-empty, empty+online,
empty+offline, REST failure). adapters_test covers basic round-trips.
Both safe to run on CI runner — no drift open required.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
bvandeusen