Changes the AlbumCoverProvider and ArtistArtProvider interfaces from
MBID-only string parameters to ref-struct signatures so name-based
providers (Deezer, Last.fm in upcoming tasks) can act on rows
without MBIDs.
Today, 53 of 213 artists in the dev DB have NULL MBIDs — featured
artists, remixers, and compilation contributors created from
track-tag splits where the primary-artist MBID is in the file but
collaborator IDs aren't. These rows are unreachable by the current
MBID-only chain. Refactoring the interface unblocks future
name-based providers from acting on them.
TheAudioDB and MBCAA keep MBID-only behavior internally: they return
ErrNotFound when ref.MBID is empty rather than attempting a
name-based fallback. The MBID guard inside EnrichAlbum/EnrichArtist
is removed; providers receive the ref unconditionally and decide
whether they can act on it.
GetAlbumWithFirstTrackPath now JOINs artists to return artist_name
alongside the existing fields, supporting AlbumRef construction.
No behavioral change today (only TheAudioDB + MBCAA registered, both
keep MBID-only behavior). The change unblocks T3 (Deezer) and T4
(Last.fm) which can now register and act on every artist/album
regardless of MBID presence.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
revive's unused-parameter rule flagged 7 test handler/method args:
- provider_test.go: fakeProvider.Configure(s) and
fakeAlbumProvider.FetchAlbumCover(ctx, mbid) — interface
conformance dummies that don't use their args.
- provider_mbcaa_test.go: 4 httptest handlers that ignore one or
both of (w, r).
- provider_theaudiodb_test.go: the disabled-provider negative
test's httptest handler.
All 7 renamed to _ per revive's convention.
Defines the abstraction every cover-art source will implement:
- Provider — base interface (ID, DisplayName, RequiresAPIKey,
DefaultEnabled, Configure).
- AlbumCoverProvider — opt-in capability for fetching album covers
by MBID.
- ArtistArtProvider — opt-in capability for fetching artist thumb +
fanart atomically by MBID.
- TestableProvider — opt-in capability for the admin Test-Connection
button.
Sentinel ErrNotTestable / ErrProviderNotFound. ErrNotFound and
ErrTransient stay in fetcher.go for now; they move into provider.go
in the next commit when fetcher.go is deleted as part of the MBCAA
refactor.
Compile-time registry: providers register from init() in their own
file. Duplicate IDs panic at startup (compiled-in registration is a
build-time bug, not a runtime concern).
Tests cover: Register adds, duplicate panics, ProviderByID success
+ ErrProviderNotFound, capability-interface filtering via Go type
assertion.
bvandeusen