Skip to main content

Payment Gateway Integration

Integrasi dengan berbagai metode pembayaran

๐ŸŽฏ Overview

Payment adalah salah satu fitur utama dalam MStore Mobile yang menyediakan fungsionalitas untuk integrasi dengan berbagai metode pembayaran.

๐Ÿ“‹ Features

  • โœ… Cash payment
  • โœ… Card payment (EDC)
  • โœ… E-Wallet (GoPay, OVO, Dana)
  • โœ… Bank transfer
  • โœ… QRIS
  • โœ… Split payment
  • โœ… Payment validation

๐Ÿ—๏ธ Architecture

BLoC Implementation

BLoC: PaymentBloc
// Events
abstract class PaymentEvent extends Equatable {}

class LoadPayment extends PaymentEvent {}
class CreatePayment extends PaymentEvent {}
class UpdatePayment extends PaymentEvent {}
class DeletePayment extends PaymentEvent {}

// States
abstract class PaymentState extends Equatable {}

class PaymentInitial extends PaymentState {}
class PaymentLoading extends PaymentState {}
class PaymentLoaded extends PaymentState {}
class PaymentError extends PaymentState {}

// BLoC
class PaymentBloc extends Bloc<PaymentEvent, PaymentState> {
  final PaymentRepository _repository;
  
  PaymentBloc({required PaymentRepository repository})
      : _repository = repository,
        super(PaymentInitial()) {
    on<LoadPayment>(_onLoad);
    on<CreatePayment>(_onCreate);
    on<UpdatePayment>(_onUpdate);
    on<DeletePayment>(_onDelete);
  }
  
  Future<void> _onLoad(
    LoadPayment event,
    Emitter<PaymentState> emit,
  ) async {
    emit(PaymentLoading());
    
    final result = await _repository.getPayments();
    
    result.fold(
      (failure) => emit(PaymentError(failure.message)),
      (data) => emit(PaymentLoaded(data)),
    );
  }
}

Repository Pattern

abstract class PaymentRepository {
  Future<Either<Failure, List<Payment>>> getPayments();
  Future<Either<Failure, Payment>> getPaymentById(String id);
  Future<Either<Failure, Payment>> createPayment(Payment data);
  Future<Either<Failure, Payment>> updatePayment(String id, Payment data);
  Future<Either<Failure, void>> deletePayment(String id);
}

class PaymentRepositoryImpl implements PaymentRepository {
  final PaymentApi _api;
  final PaymentLocalRepository _localRepo;
  
  @override
  Future<Either<Failure, List<Payment>>> getPayments() async {
    try {
      // Try local first (offline-first)
      final local = await _localRepo.getPayments();
      
      // Sync with API in background
      final result = await _api.getPayments();
      result.fold(
        (failure) => null,
        (data) => _localRepo.savePayments(data),
      );
      
      return Right(local.isNotEmpty ? local : result.getOrElse(() => []));
    } catch (e) {
      return Left(UnexpectedFailure(e.toString()));
    }
  }
}

๐Ÿ“ก API Integration

Endpoints

  • /api/v1/payments/*

Request/Response Examples

Get List

GET /api/v1/payments/*
Authorization: Bearer {access_token}
Response:
{
  "success": true,
  "data": [
    {
      "id": "123",
      "name": "Example",
      "created_at": "2024-10-14T10:00:00Z"
    }
  ],
  "pagination": {
    "page": 1,
    "limit": 20,
    "total": 100
  }
}

๐Ÿ’พ Local Database (Isar)

Schema

  • PaymentLocal
@collection
class PaymentLocal {
  Id id = Isar.autoIncrement;
  
  @Index()
  String? paymentId;
  
  String? name;
  DateTime? createdAt;
  DateTime? updatedAt;
  DateTime? syncedAt;
  
  bool? isSynced;
  bool? isDeleted;
}

Queries

// Get all
final items = await isar.paymentLocals.where().findAll();

// Get by ID
final item = await isar.paymentLocals
    .filter()
    .paymentIdEqualTo(id)
    .findFirst();

// Search
final results = await isar.paymentLocals
    .filter()
    .nameContains(query, caseSensitive: false)
    .findAll();

// Get unsynced
final unsynced = await isar.paymentLocals
    .filter()
    .isSyncedEqualTo(false)
    .findAll();

๐Ÿ”„ Offline-First Strategy

Write Operations

  1. Save to local Isar immediately
  2. Show success to user
  3. Add to sync queue
  4. Background sync when online
  5. Update with server response

Read Operations

  1. Read from local Isar (fast)
  2. Show to user immediately
  3. Background fetch from API
  4. Update local cache if changed
  5. Notify UI if data updated

Conflict Resolution

  • Strategy: Last-write-wins
  • Timestamp: Server timestamp as source of truth
  • Logging: All conflicts logged for audit

๐ŸŽจ UI Components

Main Screen

class PaymentPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return BlocProvider(
      create: (context) => getIt<PaymentBloc>()..add(LoadPayment()),
      child: Scaffold(
        appBar: AppBar(title: Text('Payment Gateway Integration')),
        body: BlocBuilder<PaymentBloc, PaymentState>(
          builder: (context, state) {
            if (state is PaymentLoading) {
              return Center(child: CircularProgressIndicator());
            }
            
            if (state is PaymentError) {
              return ErrorWidget(message: state.message);
            }
            
            if (state is PaymentLoaded) {
              return PaymentListView(items: state.items);
            }
            
            return SizedBox.shrink();
          },
        ),
        floatingActionButton: FloatingActionButton(
          onPressed: () => _navigateToCreate(context),
          child: Icon(Icons.add),
        ),
      ),
    );
  }
}

๐Ÿงช Testing

Unit Tests

void main() {
  group('PaymentBloc', () {
    late PaymentBloc bloc;
    late MockPaymentRepository mockRepository;

    setUp(() {
      mockRepository = MockPaymentRepository();
      bloc = PaymentBloc(repository: mockRepository);
    });

    tearDown(() {
      bloc.close();
    });

    test('initial state is PaymentInitial', () {
      expect(bloc.state, equals(PaymentInitial()));
    });

    blocTest<PaymentBloc, PaymentState>(
      'emits [Loading, Loaded] when Load succeeds',
      build: () {
        when(() => mockRepository.getPayments()).thenAnswer(
          (_) async => Right([Payment(id: '1', name: 'Test')]),
        );
        return bloc;
      },
      act: (bloc) => bloc.add(LoadPayment()),
      expect: () => [
        PaymentLoading(),
        isA<PaymentLoaded>(),
      ],
    );
  });
}

๐Ÿ“Š Performance Considerations

  • Lazy Loading: Load data on demand
  • Pagination: Implement pagination for large datasets
  • Caching: Cache frequently accessed data
  • Indexing: Use Isar indexes for fast queries
  • Background Sync: Sync in background to avoid blocking UI

๐Ÿ” Security

  • Authorization: Check user permissions before operations
  • Data Encryption: Sensitive data encrypted in Isar
  • Input Validation: Validate all user inputs
  • Audit Trail: Log all operations for audit

๐Ÿ“ฑ Platform-Specific

iOS

  • Use Cupertino widgets
  • Follow iOS HIG
  • Handle safe area insets

Android

  • Use Material widgets
  • Follow Material Design
  • Handle back button

Last Updated: October 14, 2024
Status: โœ… Production Ready