fl_bustter #

A lightweight Dart command bus and validation framework inspired by CQRS (Command Query Responsibility Segregation) patterns. Designed for clean, testable, and scalable architecture in Dart or Flutter applications.

✨ Features #

• 📨 Busster: A simple request/handler dispatcher.
• ✅ IValidator: Built-in validation system with rules like notEmpty, emailAddress, mustMatch, isIn, and nested.
• 📦 Easy integration with custom request types and handlers.
• 🧪 Fully testable.

📦 Installation #

Add this to your pubspec.yaml:

dependencies:
  fl_bustter: ^1.0.1

Then run:

dart pub get

📦 Getting Started #

1. Create a Response #

class LoginResponse {
  final String token;
  LoginResponse(this.token);
}

2. Create a Request #

class LoginRequest extends IRequest<LoginResponse> {
  final String email;
  final String password;

  LoginRequest({required this.email, required this.password});
}

3. Create a Validator #

class LoginValidator extends IValidator<LoginRequest> {
  @override
  void buildRules() {
    ruleFor((x) => x.email, 'email')
        .notEmpty()
        .emailAddress()
        .withMessage('Please enter a valid email');

    ruleFor((x) => x.password, 'password')
        .notEmpty()
        .minLength(6)
        .withMessage('Password must be at least 6 characters');
  }
}

4. Create a Request #

class LoginRequest extends IRequest<String> {
  final String email;
  final String password;

  LoginRequest({required this.email, required this.password});
}

5. Create a Handler #

class LoginHandler extends IHandler<LoginRequest, LoginResponse> {
  LoginHandler() : super(LoginValidator());

  @override
  Future<LoginResponse> handle(LoginRequest request) async {
    await Future.delayed(Duration(seconds: 5));

    // Simulate login logic
    if (request.email == 'test@example.com' &&
        request.password == 'password123') {
      return LoginResponse("token_string_example");
    } else {
      throw Exception('Invalid email or password');
    }
  }
}

5. Register in Busster #

void main()  {
  final busster = Busster();

  // Register the handler
  busster.registerHandler<LoginRequest, LoginResponse>(LoginHandler());
}

6. Use Busster #

void call() async {
   
  try {
    final request = LoginRequest(email: 'test@example.com', password: 'password123');
    final result = await busster.send<LoginResponse>(request);
    print(result.token); // Login successful: token_string_example
  } on ValidationException catch (e) {
    print('Validation failed:');
    print(e.toString());
  } catch (e) {
    print('Error: $e');
  }
}

📁 Example #

See example/main.dart for a working login use case.

🧪 Tests #

Run tests using:

dart test

📄 License #

This project is licensed under the MIT License.