private ViewProjection <TView, TId> projectEvent <TEvent>(
Func <IDocumentSession, object, Guid, TId> viewIdSelector,
Func <IDocumentSession, object, Guid, List <TId> > viewIdsSelector,
Action <TView, TEvent> handler,
ProjectionEventType type = ProjectionEventType.Modify) where TEvent : class
{
if (viewIdSelector == null && viewIdsSelector == null)
{
throw new ArgumentException($"{nameof(viewIdSelector)} or {nameof(viewIdsSelector)} must be provided.");
}
if (handler == null && type == ProjectionEventType.Modify)
{
throw new ArgumentNullException(nameof(handler));
}
EventHandler eventHandler;
if (type == ProjectionEventType.Modify)
{
eventHandler = new EventHandler(viewIdSelector, viewIdsSelector, (view, @event) => handler(view, @event as TEvent), type);
}
else
{
eventHandler = new EventHandler(viewIdSelector, viewIdsSelector, null, type);
}
_handlers.Add(typeof(TEvent), eventHandler);
return(this);
}
public EventHandler(
Func <IDocumentSession, object, Guid, TId> idSelector,
Func <IDocumentSession, object, Guid, List <TId> > idsSelector,
Action <TView, object> handler,
ProjectionEventType type)
{
IdSelector = idSelector;
IdsSelector = idsSelector;
Handler = handler;
Type = type;
}
public EventHandler(
Func <IDocumentSession, object, Guid, TId> idSelector,
Func <IDocumentSession, object, Guid, List <TId> > idsSelector,
Func <IDocumentSession, TView, object, Task> handler,
Func <IDocumentSession, TView, object, Task <bool> > shouldDelete,
ProjectionEventType type)
{
IdSelector = idSelector;
IdsSelector = idsSelector;
Handler = handler;
ShouldDelete = shouldDelete ?? defaultShouldDelete;
Type = type;
}
public EventProjection(EventHandler eventHandler, TId viewId, IEvent @event, object projectionEvent)
{
ViewId = viewId;
Type = eventHandler.Type;
if (Type == ProjectionEventType.Delete)
{
ShouldDelete = (session, view) => eventHandler.ShouldDelete(session, view, projectionEvent ?? @event.Data);
}
else
{
ProjectTo = (session, view) => eventHandler.Handler(session, view, projectionEvent ?? @event.Data);
}
}
public EventProjection(EventHandler eventHandler, TId viewId, IEvent @event, object projectionEvent)
{
ViewId = viewId;
Type = eventHandler.Type;
if (projectionEvent != null)
{
// Event handler uses ProjectionEvent generic
ProjectTo = view => eventHandler.Handler(view, projectionEvent);
}
else
{
ProjectTo = view => eventHandler.Handler(view, @event.Data);
}
}
private ViewProjection <TView, TId> projectEvent <TEvent>(
Func <IDocumentSession, object, Guid, TId> viewIdSelector,
Func <IDocumentSession, object, Guid, List <TId> > viewIdsSelector,
Func <IDocumentSession, TView, TEvent, Task> handler,
Func <IDocumentSession, TView, TEvent, Task <bool> > shouldDelete = null,
ProjectionEventType type = ProjectionEventType.CreateAndUpdate) where TEvent : class
{
if (viewIdSelector == null && viewIdsSelector == null)
{
throw new ArgumentException($"{nameof(viewIdSelector)} or {nameof(viewIdsSelector)} must be provided.");
}
if (handler == null && type == ProjectionEventType.CreateAndUpdate)
{
throw new ArgumentNullException(nameof(handler));
}
EventHandler eventHandler;
if (type == ProjectionEventType.CreateAndUpdate || type == ProjectionEventType.UpdateOnly)
{
eventHandler = new EventHandler(
viewIdSelector,
viewIdsSelector,
(session, view, @event) => handler(session, view, @event as TEvent),
null,
type);
}
else
{
eventHandler = new EventHandler(
viewIdSelector,
viewIdsSelector,
null,
shouldDelete == null
? (Func <IDocumentSession, TView, object, Task <bool> >)null
: (session, view, @event) => shouldDelete(session, view, @event as TEvent),
type);
}
_handlers.Add(typeof(TEvent), eventHandler);
return(this);
}