No Handler Registered CQRS-ES - structuremap

Question

I am creating a cqrs-es test application. I scan command handler against command by following code
public class StructureMapCommandHandlerFactory : ICommandHandlerFactory
{
public ICommandHandler<T> GetHandler<T>() where T : Command
{
var handlers = GetHandlerTypes<T>().ToList();
var cmdHandler = handlers.Select(handler =>
(ICommandHandler<T>)ObjectFactory.GetInstance(handler)).FirstOrDefault();
return cmdHandler;
}
private IEnumerable<Type> GetHandlerTypes<T>() where T : Command
{
var handlers = typeof(ICommandHandler<>).Assembly.GetExportedTypes()
.Where(x => x.GetInterfaces()
.Any(a => a.IsGenericType && a.GetGenericTypeDefinition() == typeof(ICommandHandler<>)))
.Where(h => h.GetInterfaces()
.Any(ii => ii.GetGenericArguments()
.Any(aa => aa == typeof(T)))).ToList();
return handlers;
}
}
I dispatches command as follows:
public class CommandBus:ICommandBus
{
private readonly ICommandHandlerFactory _commandHandlerFactory;
public CommandBus(ICommandHandlerFactory commandHandlerFactory)
{
_commandHandlerFactory = commandHandlerFactory;
}
public void Send<T>(T command) where T : Command
{
var handler = _commandHandlerFactory.GetHandler<T>();
if (handler != null)
{
handler.Execute(command);
}
else
{
throw new UnregisteredDomainCommandException("no handler registered");
}
}
}
When I run the project it throw an exception
"No Handler Registered"
My project location is https://drive.google.com/file/d/0B1rU7HOTfLwea0tVOXdIb2Nib2M/edit?usp=sharing
The Stack-Trace of this exception as follow:
[UnregisteredDomainCommandException: no handler registered]
CQRS.Infrastructure.Messaging.CommandBus.Send(T command) in f:\Video\Latest Readable\CQRS Tutorial\CQRS By Authors\HRMSystem\CQRS.Infrastructure\Messaging\CommandBus.cs:31
HRMSWeb.Facade.DiaryItemFacade.Delete(Guid id) in f:\Video\Latest Readable\CQRS Tutorial\CQRS By Authors\HRMSystem\HRMSWeb\Facade\DiaryItemFacade.cs:59
HRMSWeb.Controllers.HomeController.Delete(Guid id) in f:\Video\Latest Readable\CQRS Tutorial\CQRS By Authors\HRMSystem\HRMSWeb\Controllers\HomeController.cs:29
lambda_method(Closure , ControllerBase , Object[] ) +184
System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) +14
System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary2 parameters) +211
System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary2 parameters) +27
System.Web.Mvc.Async.<>c_DisplayClass42.b_41() +28
System.Web.Mvc.Async.<>c_DisplayClass81.<BeginSynchronous>b__7(IAsyncResult _) +10
System.Web.Mvc.Async.WrappedAsyncResult1.End() +57
System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +48
System.Web.Mvc.Async.<>c_DisplayClass39.b_33() +57
System.Web.Mvc.Async.<>c_DisplayClass4f.b_49() +223
System.Web.Mvc.Async.<>c_DisplayClass37.b_36(IAsyncResult asyncResult) +10
System.Web.Mvc.Async.WrappedAsyncResult1.End() +57
System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +48
System.Web.Mvc.Async.<>c__DisplayClass2a.<BeginInvokeAction>b__20() +24
System.Web.Mvc.Async.<>c__DisplayClass25.<BeginInvokeAction>b__22(IAsyncResult asyncResult) +102
System.Web.Mvc.Async.WrappedAsyncResult1.End() +57
System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +43
System.Web.Mvc.<>c_DisplayClass1d.b_18(IAsyncResult asyncResult) +14
System.Web.Mvc.Async.<>c_DisplayClass4.b_3(IAsyncResult ar) +23
System.Web.Mvc.Async.WrappedAsyncResult1.End() +62
System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +57
System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +23
System.Web.Mvc.Async.WrappedAsyncResult1.End() +62
System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +47
System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +10
System.Web.Mvc.<>c_DisplayClass8.b_3(IAsyncResult asyncResult) +25
System.Web.Mvc.Async.<>c_DisplayClass4.b__3(IAsyncResult ar) +23
System.Web.Mvc.Async.WrappedAsyncResult`1.End() +62
System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +47
System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9629708
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

Answer 1

The problem is on your ObjectFactory.
I don't know if you use some DI container (I can't see your code), but it can't retrieve your handlers.
You should use some kind of Typed Factory, so you could retrieve more than one commandHandler (as you do in your code).
I send you the link of my training journey into CQRS/ES: it's very similar to what you're doing and there are some articles about the journey.
I Hope it helps.