CODESAMPLE

Space-Based Architecture - Dart

Space-Based Architecture Dart

The Space-Based Architecture pattern decouples an application into independent, self-contained “spaces” that communicate via messages. Each space manages its own state and logic, reducing global state and improving modularity. This implementation uses Dart’s StreamController to create these spaces and message passing. Each space exposes a stream for receiving commands and a stream for emitting events. The main function orchestrates interactions between spaces by sending commands and listening for events. This approach aligns with Dart’s asynchronous programming model and promotes a reactive, event-driven architecture, making it well-suited for complex applications.

import 'dart:async';

// Define a Space (component)
class Space {
  final StreamController<String> _commandController = StreamController<String>();
  final StreamController<String> _eventController = StreamController<String>();

  Stream<String> get commands => _commandController.stream;
  Stream<String> get events => _eventController.stream;

  void handleCommand(String command) {
    print('Space received command: $command');
    // Simulate processing
    Future.delayed(Duration(milliseconds: 500), () {
      _eventController.sink.add('Processed: $command');
    });
  }

  void close() {
    _commandController.close();
    _eventController.close();
  }
}

void main() {
  final space1 = Space();
  final space2 = Space();

  // Listen for events from space1
  space1.events.listen((event) => print('Main received event from Space 1: $event'));

  // Listen for events from space2
  space2.events.listen((event) => print('Main received event from Space 2: $event'));

  // Send commands to spaces
  space1.commands.sink.add('Command A');
  space2.commands.sink.add('Command B');
  space1.commands.sink.add('Command C');

  // Allow time for processing and event emission
  Future.delayed(Duration(seconds: 2), () {
    space1.close();
    space2.close();
    print('Spaces closed.');
  });
}