zef_orchestration_core

This Dart library provides a flexible and efficient way to handle and orchestrate requests using a command and query pattern. It's designed to facilitate the separation of command and query operations, enabling clear and maintainable code structures for complex applications.

Features

  • Generic Request Handling: Define request handlers that process specific types of requests and return corresponding results.
  • Command and Query Separation: Separate handling of command and query operations for clear distinction between actions that change state and those that retrieve data.
  • Asynchronous Support: Built-in support for asynchronous operations, enabling non-blocking I/O operations.
  • Singleton Orchestrator: Central orchestrator instance to manage command and query handlers, ensuring a single point of orchestration.

Getting Started

Installation

To integrate this library into your Dart or Flutter project, add the following dependency to your pubspec.yaml file:

dependencies:
  your_library_name: latest_version

Quick Start

Initializing the Orchestrator

Before using the Orchestrator, initialize it:

void main() {
  OrchestratorBuilder().build();
}

If you have implemented a custom OrchestratorAdapter, you should initialize the Orchestrator with using it:

void main() {
  OrchestratorBuilder()
    .withAdapter(YourCustomOrchestratorAdapter())
    .build();
}

Defining Requests and Handlers

Create your command and query requests along with their respective handlers. Each handler should implement the corresponding abstract handler class:

class SampleCommand extends Command {
  // Implementation details
}

class SampleCommandHandler extends CommandHandler<SampleCommand> {
  @override
  Future<void> call(SampleCommand command) async {
    // Command handling logic
  }
}

Registering Handlers with the Orchestrator

Register your command and query handlers with the orchestrator to enable their processing:

Orchestrator.I.registerCommandHandler(SampleCommandHandler());

Using the Orchestrator to Send Commands and Queries

Send commands and queries through the orchestrator and handle the results as needed:

await Orchestrator.I.publish(SampleCommand());
// For queries with expected results
var queryResult = await Orchestrator.I.send(SampleQuery());

Registering Handlers with a factory

You can also register your RequestHandler via a factory, so the instances won't be stored in memory. This can reduce the memory usage, but keep in mind that it can lead the decreased performance when sending or publish a request, as the Orchestrator tries to resolve an instance. However if you register your RequestHandler via dependency injection as a Lazy, the RequestHandler instance will be resolved at the first time it is needed. This decreases startup time and memory usage. So we recommend going that way.

Orchestrator.I.registerCommandHandlerFactory(() => SampleCommandHandler());

Note: this is now a factory, which directly returns an instance every time we send the appropriate Command.

Contributing

Contributions to this library are welcome. Please feel free to submit pull requests or open issues to discuss proposed changes or enhancements.

Libraries

zef_orchestration_core