CCSWE.nanoFramework.Mediator 0.3.31

CCSWE.nanoFramework.Mediator

A simple asynchronous mediator implementation for nanoFramework. Provides in-process publisher-subscriber communication while keeping all parties decoupled.

Based on Mako-IoT.Device.Services.Mediator

Usage

Create classes for your events

public class Event1 : IMediatorEvent
{
    public string Data { get; set; }
}

public class Event2 : IMediatorEvent
{
    public string Text { get; set; }
}

Your event subscriber must implement IMediatorEventHandler interface

public class EventHandlerService : IMediatorEventHandler
{
    public void HandleEvent(IMediatorEvent mediatorEvent)
    {
        switch (mediatorEvent)
        {
            case Event1 event1:
                Debug.WriteLine($"[{nameof(EventHandlerService)}] Event1 received. The data is: {event1.Data}");
                break;
            case Event2 event2:
                Debug.WriteLine($"[{nameof(EventHandlerService)}] Event2 received The text is: {event2.Text}");
                break;
        }
    }
}

Use IMediator to publish events

public class EventPublisherService : IEventPublisherService
{
    private readonly IMediator _mediator;

    public EventPublisherService(IMediator mediator)
    {
        _mediator = mediator;
    }

    public void DoSomething()
    {
        _mediator.Publish(new Event2 { Text = "Hello from EventPublisherService" });
    }
}

Register AsyncMediator and singleton subscribers to an IHostBuilder ...

    var hostBuilder = new HostBuilder();
    hostBuilder.UseMediator(options =>
    {
        options.AddSubscriber(typeof(Event1), typeof(Service2));
        options.AddSubscriber(typeof(Event2), typeof(Service2));
    });

... or directly to an IServiceCollection

    var serviceCollection = new ServiceCollection();
    serviceCollection.AddMediator(options =>
    {
        options.AddSubscriber(typeof(Event1), typeof(Service2));
        options.AddSubscriber(typeof(Event2), typeof(Service2));
    });

For transient and scoped services you can use the Subscribe and Unsubscribe overloads that take a specific instance.

public class TransientService : IDisposable
{
    private readonly IMediator _mediator;

    public TransientService(IMediator mediator)
    {
        _mediator = mediator;
        _mediator.Subscribe(typeof(Event1), this);
        _mediator.Subscribe(typeof(Event2), this);
    }

    public void Dispose()
    {
        _mediator.Unsubscribe(typeof(Event1), this);
        _mediator.Unsubscribe(typeof(Event2), this);
    }
}