private static Dictionary <Type, EventTypeApplyDelegates> CreateAggregateEventDelegates()
{
var delegates = new Dictionary <Type, EventTypeApplyDelegates>();
var componentTypes = typeExplorer.GetAllTypes()
.Where(x => typeof(IComponent).IsAssignableFrom(x) &&
!x.IsAbstract && !x.IsGenericTypeDefinition);
foreach (Type aggregateType in componentTypes)
{
EventTypeApplyDelegates aggApplyDelegates = new EventTypeApplyDelegates();
delegates.Add(aggregateType, aggApplyDelegates);
AddTypeDelegates(aggregateType, aggApplyDelegates);
}
return(delegates);
}
private static void AddTypeDelegates(Type componentType, EventTypeApplyDelegates applyDelegates)
{
if (componentType.BaseType != null &&
typeof(IComponent).IsAssignableFrom(componentType.BaseType))
{
AddTypeDelegates(componentType.BaseType, applyDelegates);
}
var applyMethods = componentType
.GetMethods(BindingFlags.Instance | BindingFlags.InvokeMethod | BindingFlags.NonPublic)
.Where(x => x.Name == "Apply" &&
x.GetParameters().Length == 1 &&
typeof(DomainAggregateEvent).IsAssignableFrom(x.GetParameters()[0].ParameterType));
foreach (MethodInfo applyMethod in applyMethods)
{
Type eventType = applyMethod.GetParameters()[0].ParameterType;
// Create an Action<AggregateRoot, IEvent> that does (agg, evt) => ((ConcreteAggregate)agg).Apply((ConcreteEvent)evt)
var evtParam = Expression.Parameter(typeof(DomainAggregateEvent), "evt");
var aggParam = Expression.Parameter(typeof(IComponent), "agg");
var eventDelegate = Expression.Lambda(
Expression.Call(
Expression.Convert(
aggParam,
componentType),
applyMethod,
Expression.Convert(
evtParam,
eventType)),
aggParam,
evtParam).Compile();
applyDelegates[eventType] = (Action <IComponent, DomainAggregateEvent>)eventDelegate;
}
}
