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How to decorate a dependency twice with StructureMap

I have a dependency configured in StructureMap and would like to decorate it twice. I have used the EnrichWith method like below but only the second decorator gets executed (ResultistAdvertisementInjector). If I switch them only the other decorator gets executed.
For<IResultListViewModelMapper<ZoekObject>>().Use<ResultListViewModelMapper<ZoekObject>>()
.EnrichWith(original => new ResultListDateSeparatorInjector<ZoekObject>(original))
.EnrichWith(original => new ResultistAdvertisementInjector<ZoekObject>(original));
How can I enrich a dependency with two decorators?

You can just nest the 'decorating' classes yourself, for example like:
For<IResultListViewModelMapper<ZoekObject>>().Use<ResultListViewModelMapper<ZoekObject>>()
.EnrichWith(original =>
new ResultListDateSeparatorInjector<ZoekObject>(
new ResultistAdvertisementInjector<ZoekObject>(original)));

Off the top of my head, I think you can do something like this:
For<IResultListViewModelMapper<ZoekObject>>()
.Use<ResultListViewModelMapper<ZoekObject>>()
.EnrichWith(original =>
new ResultListDateSeparatorInjector<ZoekObject>(
new ResultistAdvertisementInjector<ZoekObject>(original)));

Registering instances of same type with Simple Injector

I have just picked up Simple Injector and all I currently want to do is this:
Container.Register<IMessageHandler>(() => new MessageHandlerOne());
Container.Register<IMessageHandler>(() => new MessageHandlerTwo());
I'm just trying to register two message handlers, so I can later iterate through them.
To get back these registered instances, this method sounds like it would do the trick.
var instances = Container.GetAllInstances<IMessageHandler>();
//why doesn't instances contain both MessageHandlerOne, and MessageHandlerTwo ?
Instead this returns back an empty IEnumerable.
What am I doing wrong? For something named Simple Injector you would think this would work? Am I thinking about this the wrong way?

What you are trying to do should fail with an exception on the second call to Container.Register<IMessageHandler> since the Simple Injector API clearly differentiates the registration of collections.
In other words, if you want to resolve a collection, you should register a collection:
Container.Collection.Register<IMessageHandler>(
typeof(MessageHandlerOne),
typeof(MessageHandlerTwo));

Ninject: How to bind ToMethod

i want to config my bindings.
Bind<DbContext>().To<HangTagVerwaltungContext>();
Bind<IUnitOfWork>()
.ToConstructor(
x => new UnitOfWork(true, true, x.Inject<DbContext>()));
// Managers
Bind<ITagManager>().To<TagManager>();
// ViewModels
Bind<TagEditViewModel>().ToMethod(
context =>
{
IUnitOfWork unitOfWork = context.Kernel.Get<IUnitOfWork>();
ITagManager tagManager =
context.Kernel.Get<ITagManager>(
new Parameter(#"unitOfWork", unitOfWork, false));
return new TagEditViewModel(tagManager,
context.Kernel.Get<INavigationService>(), unitOfWork);
});
My Problem is, that everytime he is creating a new UnitOfWork for the TagManager and not use the Parameter i give him in the ToMethod method. What do i wrong?
Thx for the Help.
Dennis

I think you should be using ConstructorArgument instead of Parameter. The parameter name will have to match that of the constructor.
However, why are you doing this so complicated? (DI is about making things easier for you, not more complicated.) Is it because you need the same IUnitOfWork instance for tagManager and TagEditViewModel?
If that's the case, there's other ways to achieve this. You should look into scopes. They are used to make some part of the object tree use the same instance.
For the scenario you showed you might want to try .InCallScope(), but generally for IUnitOfWork there's other things which work better in the whole application, like .InRequestScope() for web projects or some other custom scope. There's other stackoverflow questions already covering this.

Having Automapper use services constructed by a Autofac with WebApi

I'm using WebAPI + Autofac + Automapper, with a repository for data access. I need to map a model to my domain entities, specifically, I need to convert an identity value to the actual entity. No big deal, right? I've done this in MVC with no problem. I will simplify what I am doing to expose the essentials.
public class EntityConverter<T> : ITypeConverter<int, T>
where T : Entity
{
public EntityConverter(IRepository<T> repository)
{
_repository = repository;
}
private readonly IRepository<T> _repository;
public T Convert(ResolutionContext context)
{
_repository.Get((int) context.SourceValue);
}
}
Repositories are registered with Autofac, and are managed as InstancePerApiRequest because of session/transaction management. So, I need to register my converter in that same scope:
builder.RegisterGeneric(typeof(EntityConverter<>))
.AsSelf()
.InstancePerApiRequest();
The Automapper config looks something like:
var container = builder.Build(); // build the Autofac container and do what you will
Mapper.Initialize(cfg => {
cfg.ConstructServicesUsing(container.Resolve); // nope nope nope
// configure mappings
cfg.CreateMap<int, TestEntity>().ConvertUsing<EntityConverter<TestEntity>>()
});
Mapper.AssertConfigurationIsValid();
So here's the part that sucks. I am to understand Automapper requires the ConstructServicesUsing guy to be set before you build your config. If you set it later, it won't be used. The example above won't work because container is the root scope. If I try and resolve EntityConverter<TestEntity>, Autofac will complain that the requested type is registered for a different scope, and the one you're in ain't it. Makes sense, I want the scope created by WebApi.
Let me pause a sec and cover one fact about WebApi dependency injection (I don't really think this is Autofac-specific). WebApi creates an IDependencyScope for the request, and stashes it in the HttpRequestMessage.Properties. I can't get it back again unless I have access to that same HttpRequestMessage instance. My AsInstancePerApiRequest scoping on IRepository and my converter thus rely on that IDependencyScope.
So, that's really the meat and potatoes of the problem, and I really frustrated with this difference from MVC. You can't do
cfg.ConstructServicesUsing(GlobalConfiguration.Configuration.DependencyResolver.GetService);
That's equivalent to using container.Resolve. I can't use
GlobalConfiguration.Configuration.DependencyResolver.BeginScope().GetService
because A) that creates a new scope next to the one I actually want B) doesn't really let me clean up the new scope I created. Using Service Locator is a new way to have the same problem; I can't get to the scope WebApi is using. If my converter and its dependencies were single instance or instance per dependency, it wouldn't be a problem, but they aren't, so it is, and changing that would create lots more problems for me.
Now, I can create AutoMapper config with Autofac and register it as a single instance. I can even create per-request IMappingEngine instances. But that doesn't do me any good if the service constructor always uses that single delegate you register at the beginning, which has no access to the current scope. If I could change that delegate per each mapping engine instance, I might be in business. But I can't.
So what can I do?

Another option, this time it's built-in, is to use the per-map options:
Mapper.Map<Source, Destination>(dest, opt => opt.ConstructServicesUsing(type => Request.GetDependencyScope().GetService(typeof(YourServiceTypeToConstruct))));
Don't bother with setting up the global IoC config in your mapping configuration.
Another option is to use your IoC tool to configure how to instantiate the MappingEngine:
public MappingEngine(
IConfigurationProvider configurationProvider,
IDictionary<TypePair, IObjectMapper> objectMapperCache,
Func<Type, object> serviceCtor)
The first one is just Mapper.Configuration, the second should probably be a singleton, and the third you can fill in with the current nested container's resolution. This would simplify from having to call the Map overload every time.

Update: Automapper was updated to support that feature. See #Jimmy Bogard 's answer
This solution could be not very nice, but it works. The solution relates to WebAPI 2, I'm not sure about previous versions.
In WebAPI 2 you can get current IDependencyScope from current HttpRequestMessage via GetDependencyScope() extension method. Current HttpRequestMessage is stored in the Items property of the current HttpContext. Knowing that your factory could look like:
Mapper.Initialize(cfg =>
{
cfg.ConstructServicesUsing(serviceTypeToConstruct =>
{
var httpRequestMessage = HttpContext.Current.Items["MS_HttpRequestMessage"] as HttpRequestMessage;
var currentDependencyScope = httpRequestMessage.GetDependencyScope();
return currentDependencyScope.GetService(serviceTypeToConstruct);
});
// configure mappings
// ...
});

This may or may not be suitable for you.. but here goes:
We recently did this.. for model binders in MVC. Our model binders (on GET requests) now use Ninject-managed Services to build models.
Basically, we inject a factory (using Ninject's Factories extension.. perhaps there is a similar one for Autofac) into an "AutomapperBootstrapper" class, which in turn creates Automapper mapping Profile's and adds them to Automapper. Somewhat like this:
Mapper.Initialize(cfg =>
{
cfg.AddProfile(_factory.CreateServiceViewModelMappingProfile());
// etc..
});
The mappings Profile's themselves use MapFrom(), which is evaluated each time a mapping occurs. Something like this:
Mapper.CreateMap<Service, ServiceViewModel>()
.ForMember(x => x.Regions,
opt =>
opt.MapFrom(x => getRegions()))
private IEnumerable<Region> getRegions() {
return _factory.CreateTheService().GetRegions();
}
Each time the model binder is fired up, Ninject still wires up all dependencies for the request and it all filters down.
(For those interested, this setup basically lets us do this: /Area/Controller/Action/12, and our controller action method is this:
[HttpGet]
public ActionResult Action(ServiceViewModel model) {
// ...
}
).

Structure Map 2.6.1

In my current project I'm currently trying to replace the Windsor IoC in favour of structure map (2.6.1). But having a bit of problem registering some generic types. How would I register IFilterConverter<T> to use FilterConverter<SomeSpecificType>. I've tried ConnectImplementationsToTypesClosing(IFilterConverter) but from what I've read (Jimmy Bogard's article) I would need a concrete type defined like so:- SomeConcreteType : IFilterConverter<SomeSpecificType> for that to work and I don't have that.
So to reiterate if I have a type that takes a constructor argument IFilterConverter<SomeSpecificType>, I want structure map to provide me with FilterConverter<SomeSpecificType>.
With Windsor I was using the XML config option (which I want to get away from) But all I did was just set up the configuration like so:
<component id="IFilterConverter" service="SomeNamespace.IFilterConverter`1, SomeNamespace" type="SomeNamespace.FilterConverter`1, SomeNamespace" lifestyle="PerWebRequest">
How do I do the equivalent in SM (using code, not XML config files)
Thanks

I think this should do it.
_container = new Container();
_container.Configure(x =>
{
x.For(typeof (IFilterConverter<>)).Use(typeof (FilterConverter<>));
});