/// <summary>
/// Publishes information about an error that arose during the handling of an event.
/// </summary>
/// <param name="error">The error</param>
/// <returns>
/// An <see cref="IObservable{T}" /> that will be notified once each time the event is handled.
/// </returns>
public virtual IObservable <Unit> PublishErrorAsync(EventHandlingError error)
{
return(Observable.Create <Unit>(observer =>
{
errorSubject.OnNext(error);
observer.OnNext(Unit.Default);
observer.OnCompleted();
return Disposable.Empty;
}));
}
internal static IDisposable SubscribeDurablyAndPublishErrors <THandler, TEvent>(
this IObservable <TEvent> events,
THandler handler,
Action <TEvent> handle,
IEventBus bus)
where TEvent : IEvent => events.Subscribe(
onNext : e =>
{
try
{
handle(e);
}
catch (Exception exception)
{
var error = new EventHandlingError(exception, handler, e);
bus.PublishErrorAsync(error).Wait();
}
},
onError: exception => bus.PublishErrorAsync(new EventHandlingError(exception, handler))
.Wait());
internal static IDisposable SubscribeConsequences <TEvent>(
IHaveConsequencesWhen <TEvent> handler,
IObservable <TEvent> observable,
IEventBus bus)
where TEvent : IEvent => observable
.Subscribe(
onNext : e =>
{
try
{
handler.HaveConsequences(e);
}
catch (Exception exception)
{
var error = new EventHandlingError(exception, handler, e);
bus.PublishErrorAsync(error).Wait();
}
},
onError: exception => bus.PublishErrorAsync(new EventHandlingError(exception, handler))
.Wait());
internal static IDisposable SubscribeProjector <TEvent, TProjector>(
TProjector handler,
IObservable <TEvent> observable,
IEventBus bus)
where TEvent : IEvent
where TProjector : class, IUpdateProjectionWhen <TEvent> =>
observable
.Subscribe(
onNext : e =>
{
try
{
handler.UpdateProjection(e);
}
catch (Exception exception)
{
var error = new EventHandlingError(exception, handler, e);
bus.PublishErrorAsync(error).Wait();
}
},
onError: exception => bus.PublishErrorAsync(new EventHandlingError(exception, handler))
.Wait());