/// <summary>
/// Registers a dynamic event handler.
/// </summary>
/// <typeparam name="TEvent">The type of the <see cref="IEvent"/>.</typeparam>
/// <param name="config">The configuration.</param>
/// <param name="handler">The <see cref="Func{TEvent, Task}"/> delegate.</param>
public static void RegisterEventHandler <TEvent>(this ProcessorConfiguration config, Func <TEvent, Task> handler) where TEvent : IEvent
{
if (config == null)
{
throw Error.ArgumentNull("config");
}
if (handler == null)
{
throw Error.ArgumentNull("handler");
}
var descriptorProvider = config.Services.GetEventHandlerDescriptorProvider();
var mapping = descriptorProvider.GetHandlerMapping();
Type eventType = typeof(TEvent);
EventHandlersDescriptor descriptors;
if (!mapping.TryGetValue(eventType, out descriptors))
{
descriptors = new EventHandlersDescriptor(eventType.Name);
mapping.Add(typeof(TEvent), descriptors);
}
descriptors.EventHandlerDescriptors.Add(new EventHandlerDescriptor <TEvent>(config, eventType, handler));
}
EventHandlersDescriptor IEventHandlerSelector.SelectHandlers(EventHandlerRequest request)
{
EventHandlersDescriptor eventDescriptor = null;
this.traceWriter.TraceBeginEnd(
request,
TraceCategories.HandlersCategory,
TraceLevel.Info,
this.innerSelector.GetType().Name,
SelectActionMethodName,
beginTrace: null,
execute: () => eventDescriptor = this.innerSelector.SelectHandlers(request),
endTrace: tr =>
{
tr.Message = Error.Format(
Resources.TraceHandlerSelectedMessage,
FormattingUtilities.EventHandlerDescriptorsToString(eventDescriptor.EventHandlerDescriptors));
},
errorTrace: null);
Collection <EventHandlerDescriptor> handlerDescriptors = new Collection <EventHandlerDescriptor>();
foreach (var handlerDescriptor in eventDescriptor.EventHandlerDescriptors)
{
// Intercept returned EventHandlerDescriptor with a tracing version
if (handlerDescriptor != null && !(handlerDescriptor is EventHandlerDescriptorTracer))
{
handlerDescriptors.Add(new EventHandlerDescriptorTracer(handlerDescriptor, this.traceWriter));
}
else
{
handlerDescriptors.Add(handlerDescriptor);
}
}
return(new EventHandlersDescriptor(eventDescriptor.EventName, handlerDescriptors));
}
