di-registration

name	di-registration
description	Rules for dependency injection with GetIt (sl) in flutter_starter — every feature owns a di/<feature>_dependencies.dart registered in service_locator.dart, with registration order DataSources → Repository → UseCases → Cubit, and lazy-singleton vs factory guidance. Use when creating a new feature's DI file, editing service_locator.dart, or deciding how to register a service.

DI registration

1. Every feature owns its own DI file

lib/features/<feature>/di/<feature>_dependencies.dart exports register<Feature>Dependencies(). Call it from initializeDependencies() in core/di/service_locator.dart.

2. Registration order: DataSources → Repository → UseCases → Cubit

void registerOrderDependencies() {
  // Data sources — lazy singletons (stateless / long-lived)
  sl.registerLazySingleton<OrderRemoteDataSource>(
    () => OrderRemoteDataSourceImpl(sl<ApiClient>()),
  );
  sl.registerLazySingleton<OrderLocalDataSource>(
    () => OrderLocalDataSourceImpl(), // HiveStorageService is self-managed
  );

  // Repository
  sl.registerLazySingleton<OrderRepository>(
    () => OrderRepositoryImpl(remote: sl(), local: sl()),
  );

  // Use cases
  sl.registerLazySingleton<CreateOrderUseCase>(() => CreateOrderUseCase(sl()));
  sl.registerLazySingleton<GetAllOrdersUseCase>(() => GetAllOrdersUseCase(sl()));

  // Cubit — factory (fresh instance per page entry)
  sl.registerFactory<OrderCubit>(
    () => OrderCubit(createOrderUseCase: sl(), getAllOrdersUseCase: sl()),
  );
}

3. Lifetime choice

Type	Lifetime
DataSource, Repository, UseCase, stateless services	registerLazySingleton
Cubit, anything re-entered by the user	registerFactory

4. Things never registered in sl

• HiveStorageService — factory-cached per boxName internally.
• BuildContext, widgets, Flutter objects.
• One-off helpers that can be instantiated at the call site.

5. Wire it up in service_locator.dart

void initializeDependencies() {
  registerCoreDependencies();
  registerAuthenticationDependencies();
  registerOrderDependencies(); // ← add
}