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social-app/apps/lib/data/cache/hybrid_cache_store.dart
T

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1.4 KiB
Dart

import 'memory_cache_store.dart';
import 'persistent_cache_store.dart';
class HybridCacheStore {
final MemoryCacheStore memory;
final PersistentCacheStore persistent;
final Map<String, Future<dynamic>> _inflight = <String, Future<dynamic>>{};
HybridCacheStore({required this.memory, required this.persistent});
Future<T?> read<T>(String key) async {
final memoryValue = await memory.read<T>(key);
if (memoryValue != null) {
return memoryValue;
}
final persistentValue = await persistent.read<T>(key);
if (persistentValue != null) {
await memory.write(key, persistentValue);
}
return persistentValue;
}
Future<void> write<T>(String key, T value) async {
await memory.write<T>(key, value);
await persistent.write<T>(key, value);
}
Future<void> remove(String key) async {
await memory.remove(key);
await persistent.remove(key);
}
Future<T> getOrLoad<T>(String key, {required Future<T> Function() loader}) {
final running = _inflight[key];
if (running != null) {
return running.then((value) => value as T);
}
final future = () async {
final cached = await read<T>(key);
if (cached != null) {
return cached;
}
final loaded = await loader();
await write<T>(key, loaded);
return loaded;
}();
_inflight[key] = future;
return future.whenComplete(() {
_inflight.remove(key);
});
}
}