Rx EventAggregator<T> for desktop apps

In my continuing (point-less) mission to avoid using anything related to MS Prism - a quick implementation of an EventAggregator using Rx - took about 5 minutes to write for a problem I currently have, normally try and avoid using such a pattern as it can lead the scattering of business logic which can hard to 'follow' when refactoring / re-visting code.

Trying to kepp the interace as simple and obvious as possible (symetric design) - this will be injected by the container:

	public interface IEventAggregator : IDisposable
	{
	void Publish<T>(T @event) where T : BaseEvent;
	IObservable<T> Notify<T>() where T : BaseEvent;
	IObservable<T> Notify<T>(IScheduler scheduler) where T : BaseEvent;
	}

view raw IEventAggreator.cs hosted with ❤ by GitHub

Simple base event class, not thing special at the moment, might add a timestamp in the future, but more likely to do that with Rx on the event stream using the apply named Timestamp method:

	public abstract class BaseEvent
	{
	}

view raw BaseEvent.cs hosted with ❤ by GitHub

Included a simplifed Schedulers wrapper - idea being you can get any of the Rx Schedulers in one place, and importantly makes unit testing easier:

	public interface ISchedulers
	{
	IScheduler Dispatcher { get; }
	IScheduler TaskPool { get; }
	}

view raw ISchedulers.cs hosted with ❤ by GitHub

Show me the money...

	public sealed class EventAggregator : IEventAggregator, IDisposable
	{
	private readonly Subject<BaseEvent> _eventStream;
	private readonly ISchedulers _schedulers;
	public EventAggregator(ISchedulers schedulers)
	{
	_schedulers = schedulers;
	_eventStream = new Subject<BaseEvent>();
	}
	public void Dispose() => _eventStream.Dispose();
	public void Publish<T>(T @event) where T : BaseEvent => _eventStream.OnNext(@event);
	public IObservable<T> Notify<T>() where T : BaseEvent => Notify<T>(_schedulers.TaskPool);
	public IObservable<T> Notify<T>(IScheduler scheduler) where T : BaseEvent =>
	_eventStream.OfType<T>()
	.ObserveOn(scheduler);
	}

view raw EventAggregator.cs hosted with ❤ by GitHub