BAB 36. CLEAN ARCHITECTURE

Konsep

TemuBelajar mengimplementasikan Clean Architecture (Robert C. Martin) untuk memisahkan kepentingan bisnis dari detail teknis, sehingga sistem mudah diuji, diubah, dan diperluas.

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Layer Diagram

flowchart TD
    subgraph OUTER ["🌐 Outer Layer"]
        UI["📱 Presentation\n(Flutter Pages, Widgets, Controllers)"]
        API["🔌 Infrastructure\n(Laravel Controller, API Resource)"]
    end

    subgraph MIDDLE ["⚙️ Application Layer"]
        UC["📋 Use Cases\n(Business Logic)"]
    end

    subgraph INNER ["🎯 Domain Layer (Core)"]
        ENT["🏛️ Entities\n(Pure Business Objects)"]
        RI["📄 Repository Interfaces"]
    end

    subgraph DATA ["🗄️ Data Layer"]
        REPO["Repository Implementation"]
        DS["Data Source"]
        DB[("MySQL")]
    end

    UI --> UC
    API --> UC
    UC --> ENT
    UC --> RI
    RI --> REPO
    REPO --> DS
    DS --> DB

    style INNER fill:#1e1b4b,color:#a5b4fc
    style MIDDLE fill:#4c1d95,color:#ddd6fe
    style OUTER fill:#1f2937,color:#d1d5db
    style DATA fill:#064e3b,color:#a7f3d0

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Penjelasan Setiap Layer

🎯 Domain Layer — Inti Sistem

Layer paling dalam. Tidak bergantung pada apapun — tidak ada import Flutter, Laravel, atau database di sini.

Berisi:

Komponen	Deskripsi
Entities	Objek bisnis inti (Request, Booking, Meeting)
Repository Interfaces	Kontrak/abstraksi akses data
Value Objects	Tipe data bisnis (Rating, Score, Status)
Domain Events	Event yang terjadi di domain (RequestCreated, etc.)

Contoh Entity (Flutter/Dart):

class RequestEntity {
  final int id;
  final String topic;
  final String description;
  final RequestStatus status;
  final DateTime preferredTime;

  const RequestEntity({
    required this.id,
    required this.topic,
    required this.description,
    required this.status,
    required this.preferredTime,
  });
}

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⚙️ Application Layer — Use Cases

Berisi logika bisnis aplikasi. Hanya bergantung pada Domain Layer.

Contoh Use Case (Flutter/Dart):

class CreateRequestUseCase {
  final RequestRepository _repository;

  CreateRequestUseCase(this._repository);

  Future<Either<Failure, RequestEntity>> call(CreateRequestParams params) {
    return _repository.createRequest(params);
  }
}

Contoh Service (Laravel/PHP):

class RequestService
{
    public function __construct(
        private RequestRepositoryInterface $repository,
        private MatchingEngine $matchingEngine
    ) {}

    public function createRequest(CreateRequestDTO $dto): Request
    {
        $request = $this->repository->create($dto);
        $this->matchingEngine->dispatch($request);
        return $request;
    }
}

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🌐 Presentation / Infrastructure Layer

Layer terluar. Bergantung pada semua layer di bawahnya.

Flutter:

• Pages (UI)
• Widgets (komponen UI)
• Controllers/Notifiers (state management via Riverpod)

Laravel:

• Controllers (HTTP handler)
• API Resources (JSON transformer)
• Form Requests (validasi)

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Dependency Rule

:::important Aturan Utama Ketergantungan kode hanya boleh mengarah ke dalam (dari luar ke dalam). Layer dalam tidak boleh mengetahui apapun tentang layer luar. :::

✅ Presentation  → Domain
✅ Application   → Domain
✅ Data          → Domain (implements interface)
❌ Domain        → Presentation (DILARANG)
❌ Domain        → Data (DILARANG)

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Implementasi di Flutter

flowchart LR
    Page --> Controller
    Controller --> UseCase
    UseCase --> RepositoryInterface
    RepositoryInterface --> RepositoryImpl
    RepositoryImpl --> RemoteDatasource
    RemoteDatasource --> DioClient["Dio\nHTTP Client"]

    style RepositoryInterface fill:#7c3aed,color:#fff

Implementasi di Laravel

flowchart LR
    Controller --> Service
    Service --> RepositoryInterface
    RepositoryInterface --> Repository
    Repository --> Model["Eloquent\nModel"]
    Model --> MySQL[("MySQL")]

    style RepositoryInterface fill:#7c3aed,color:#fff

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Keuntungan

Keuntungan	Dampak
Testability	Domain dan Use Case bisa diuji tanpa database
Flexibility	Ganti database/framework tanpa ubah bisnis logic
Maintainability	Perubahan terlokalisir per layer
Separation of Concerns	Setiap layer punya tanggung jawab yang jelas