Autofac injecting to Controllers loaded with RegisterControllers() - asp.net-mvc

Question

Is there a way to enable injection in controllers loaded via builder.RegisterControllers() in an external assembly? When I copy the exact same assembly in my plugin folder, I get a parameterless constructor not found error.
// This doesnt work, parameterless constructor not found!
var assemblies = new DirectoryInfo(
HttpContext.Current.Server.MapPath("~/App_Plugins/"))
.GetFiles("*.dll")
.Select(r => Assembly.LoadFrom(r.FullName)).ToArray();
// This works, injection happens correctly on constructor
var assemblies = new[] {typeof (MvcApplication).Assembly};
The second one will work, while the first one will produce the error. I have tried manualy also registering the "external" controllers but still the same problem:
builder.RegisterAssemblyTypes(assemblies)
.Where(r => r.BaseType == typeof(Controller))
.InstancePerHttpRequest();
I am using the DefaultControllerFactory of mvc 4
Stack trace is this:
No parameterless constructor defined for this object.
[MissingMethodException: No parameterless constructor defined for this object.]
System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck) +0
System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) +113
System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) +232
System.Activator.CreateInstance(Type type, Boolean nonPublic) +83
System.Activator.CreateInstance(Type type) +6
System.Web.Mvc.DefaultControllerActivator.Create(RequestContext requestContext, Type controllerType) +55
[InvalidOperationException: An error occurred when trying to create a controller of type 'TestProject.Controllers.HomeController'. Make sure that the controller has a parameterless public constructor.]
System.Web.Mvc.DefaultControllerActivator.Create(RequestContext requestContext, Type controllerType) +178
System.Web.Mvc.DefaultControllerFactory.GetControllerInstance(RequestContext requestContext, Type controllerType) +77
System.Web.Mvc.DefaultControllerFactory.CreateController(RequestContext requestContext, String controllerName) +66
System.Web.Mvc.MvcHandler.ProcessRequestInit(HttpContextBase httpContext, IController& controller, IControllerFactory& factory) +191
System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, Object state) +50
System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContext httpContext, AsyncCallback callback, Object state) +48
System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.BeginProcessRequest(HttpContext context, AsyncCallback cb, Object extraData) +16
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +301
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

Answer 1

I'm not seeing Autofac involved in the stack trace. If Autofac were unhappy the exception would look something like:
[DependencyResolutionException: None of the constructors found with 'Public binding flags' on type 'SomeApp.WebApplication.Areas.Shared.Controllers.AccountController' can be invoked with the available services and parameters:
Cannot resolve parameter 'SomeApp.WebApplication.Areas.Shared.Controllers.Slappy slappy' of constructor 'Void .ctor(SomeApp.Web.LoginService, SomeApp.Web.AccountMembership.IMembershipService, SomeApp.Infrastructure.Logging.ILog, SomeApp.WebApplication.Areas.Shared.Controllers.Slappy)'.]
Autofac.Core.Activators.Reflection.ReflectionActivator.ActivateInstance(IComponentContext context, IEnumerable`1 parameters) +377
Autofac.Core.Resolving.InstanceLookup.Activate(IEnumerable`1 parameters) +48
Autofac.Core.Resolving.InstanceLookup.Execute() +48
Autofac.Core.Resolving.ResolveOperation.GetOrCreateInstance(ISharingLifetimeScope currentOperationScope, IComponentRegistration registration, IEnumerable`1 parameters) +167
Autofac.Core.Resolving.ResolveOperation.Execute(IComponentRegistration registration, IEnumerable`1 parameters) +64
Autofac.Core.Lifetime.LifetimeScope.ResolveComponent(IComponentRegistration registration, IEnumerable`1 parameters) +163
Autofac.ResolutionExtensions.TryResolveService(IComponentContext context, Service service, IEnumerable`1 parameters, Object& instance) +70
Autofac.ResolutionExtensions.ResolveOptionalService(IComponentContext context, Service service, IEnumerable`1 parameters) +53
Autofac.Integration.Mvc.AutofacDependencyResolver.GetService(Type serviceType) +59
System.Web.Mvc.DefaultControllerActivator.Create(RequestContext requestContext, Type controllerType) +41
[InvalidOperationException: An error occurred when trying to create a controller of type 'SomeApp.WebApplication.Areas.Shared.Controllers.AccountController'. Make sure that the controller has a parameterless public constructor.]
System.Web.Mvc.DefaultControllerActivator.Create(RequestContext requestContext, Type controllerType) +179
System.Web.Mvc.DefaultControllerFactory.GetControllerInstance(RequestContext requestContext, Type controllerType) +80
System.Web.Mvc.DefaultControllerFactory.CreateController(RequestContext requestContext, String controllerName) +74
System.Web.Mvc.MvcHandler.ProcessRequestInit(HttpContextBase httpContext, IController& controller, IControllerFactory& factory) +196
System.Web.Mvc.<>c__DisplayClass6.<BeginProcessRequest>b__2() +49
System.Web.Mvc.<>c__DisplayClassb`1.<ProcessInApplicationTrust>b__a() +13
System.Web.Mvc.SecurityUtil.<GetCallInAppTrustThunk>b__0(Action f) +7
System.Web.Mvc.SecurityUtil.ProcessInApplicationTrust(Action action) +22
System.Web.Mvc.SecurityUtil.ProcessInApplicationTrust(Func`1 func) +88
System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, Object state) +98
System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContext httpContext, AsyncCallback callback, Object state) +50
System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.BeginProcessRequest(HttpContext context, AsyncCallback cb, Object extraData) +16
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +301
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155
Verify you are setting the DependencyResolver.
DependencyResolver.SetResolver(new AutofacDependencyResolver(ApplicationContainer));