Always follow these rules. They ensure code quality and architectural consistency.
Clean Architecture
Simple Manager Mobile follows Clean Architecture principles strictly.
Layer Flow
The flow must always follow this pattern:
Screen → Hook → Service → Repository → Database
UI must never access database directly. Always go through the proper layers.
Layer Responsibilities
Presentation Layer
- Screens: UI components that display data and handle user interactions
- Hooks: Custom React hooks that interface with services
- Components: Reusable UI elements
Application Layer
- Services: Business logic and orchestration
- Validators: Input validation and business rules
Validation must exist in the service layer, not in the UI or repository.
Infrastructure Layer
- Repositories: Database operations only
- Database: Database setup and configuration
Repositories must only contain database logic. No business logic should exist here.
Domain Layer
- Entities: Core business objects and types
State Management
Do not introduce global state libraries. Use React’s built-in state management.
Component Style
Prefer React hooks over classes. All new components should be functional components.
Architecture Example
Here’s how the layers work together for the Records feature:
Screen Layer
// RecordsScreen.tsx
const { records, create, update, remove } = useRecords();
Hook Layer
// useRecords.ts
const service = useMemo(() => new RecordService(), []);
const create = async (title: string, type: string) => {
await service.create(title, type);
await load();
};
Service Layer
// RecordService.ts
async create(title: string, type: string) {
// Business logic and validation
const record: Record = { /* ... */ };
await this.repository.create(record);
return record;
}
Repository Layer
// RecordRepository.ts
async create(record: Record) {
// Database operations only
await database.runAsync(/* SQL */);
}
Key Takeaways
- Respect layer boundaries - Each layer has a specific responsibility
- No shortcuts - Always follow the full flow from screen to database
- Keep it simple - No unnecessary state management libraries
- Validate early - Validation belongs in the service layer
- Pure repositories - Database logic only, no business rules