bvandeusen
94727f40bb
- cache_first.dart: backtick-fence List<T> doc comment to dodge unintended_html_in_doc_comment. - library_providers.dart:163: switch single-row insert to insertAllOnConflictUpdate; Batch only exposes the *AllOnConflict* variant. - 5 test files: StreamProvider.overrideWith takes Create<Stream<T>>, not Create<Future<T>>. Wrap data emissions in Stream.value(...). - artist_detail_screen_test: add models/album.dart import for AlbumRef type annotation. - track_actions_sheet_test: drop _StubLiked extends LikedIdsController (notifier no longer exists post-migration); override with Stream.value(LikedIds(...)) instead. - like_button_test: rollback assertion now requires drift writes via LikesController. Skip under _skipDrift until libsqlite3-dev lands on the runner image (Fable #399). Replace stale .notifier reference with likesControllerProvider for completeness. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
50 lines
1.9 KiB
Dart
50 lines
1.9 KiB
Dart
// Drift-first reactive read pattern with REST cold-cache fallback (#357 plan C).
|
|
//
|
|
// Subscribes to a drift watch() stream. On each emission:
|
|
// - non-empty → map to result type T and yield
|
|
// - empty + online → fetch via REST, populate drift, await re-emission
|
|
// - empty + offline → yield mapped empty result (UI shows empty state)
|
|
//
|
|
// The pattern lets every read provider trust drift as the source of
|
|
// truth. SyncController keeps drift fresh in the background; widget
|
|
// rebuilds happen automatically as drift writes propagate via watch().
|
|
|
|
import 'dart:async';
|
|
|
|
/// Wraps the watch + cold-cache fallback pattern. Generic over:
|
|
/// D — the drift row type (or TypedResult for joins)
|
|
/// T — the result type the caller wants (e.g. `List<ArtistRef>`)
|
|
///
|
|
/// `fetchAndPopulate` is invoked when drift is empty AND `isOnline()`
|
|
/// returns true. It must populate drift via its own side-effect; the
|
|
/// drift watch() stream will re-emit and this helper yields the
|
|
/// populated rows on the next iteration.
|
|
///
|
|
/// REST failures are swallowed — the helper falls through to yielding
|
|
/// the empty result. Caller is responsible for surfacing errors via
|
|
/// toast etc.
|
|
Stream<T> cacheFirst<D, T>({
|
|
required Stream<List<D>> driftStream,
|
|
required Future<void> Function() fetchAndPopulate,
|
|
required T Function(List<D>) toResult,
|
|
required Future<bool> Function() isOnline,
|
|
}) async* {
|
|
await for (final rows in driftStream) {
|
|
if (rows.isNotEmpty) {
|
|
yield toResult(rows);
|
|
continue;
|
|
}
|
|
if (await isOnline()) {
|
|
try {
|
|
await fetchAndPopulate();
|
|
// The drift watch() stream re-emits with the populated rows on
|
|
// the next loop iteration. Don't yield here.
|
|
} catch (_) {
|
|
yield toResult(rows); // empty result; caller surfaces error
|
|
}
|
|
} else {
|
|
yield toResult(rows); // empty result; offline
|
|
}
|
|
}
|
|
}
|