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Registering AccountController with Unity IoC

Account Controller does not Register correctly
I have an ASP.NET MVC application with Individual user accounts using Identity. In my account controller I have a UserMappingService that I would like to inject.
There are two AccountController constructors, the one that was originally an empty constructor is the one that is causing issues. I need to inject the UserMappingService here. Before I added the Service to the parameters of the constructor I was able to make the controller register the empty constructor by adding this to the UnityConfig.cs
//parameterless constructor in AccountController.cs
public AccountController()
{
}
// From UnityConfig.cs in RegisterTypes method
container.RegisterType<AccountController>(new InjectionConstructor());
The problem is that once I add the service as a parameter, I get errors.
private IUserMappingService userMappingService;
//constructor with interface in the parameter AccountController.cs
public AccountController(IUserMappingService mappingService)
{
userMappingService = mappingService;
}
//From UnityConfig.cs
public static void RegisterTypes(IUnityContainer container)
{
container.RegisterType<IUserMappingService, UserMappingService>();
container.RegisterType<AccountController>(new InjectionConstructor());
}
Resulting error upon runtime is:
Error in RegisterType(Invoke.Constructor())
ArgumentException: No member matching data has been found.
I am pretty sure the (InjectionConstructor) is only good for for the default parameterless constructor, but I don't know how else to Register the controller in this case.

You can spec the dependency type like this:
var ctr = new InjectionConstructor(typeof(IUserMappingService));
container.RegisterType<AccountController>(ctr);
Or you can flag your constructor with InjectionConstructorAttribute:
[InjectionConstructor]
public AccountController(IUserMappingService mappingService)
{
userMappingService = mappingService;
}

Using Autofac with Mvc controller constructor injection

I'm having trouble with Autofac constructor injection. I'm somewhat solved my problem but I'm turning to the community for a full solution.
This works with DI
builder.RegisterControllers(typeof(MvcApplication).Assembly)
.InstancePerHttpRequest();
This does not.
builder.RegisterControllers(typeof(MvcApplication).Assembly)
.AsImplementedInterfaces()
.InstancePerHttpRequest();
Here's my controller.
public class HomeController : BaseController
{
public HomeController(IPlugin plugin)
{
}
}
I have a module to resolve the IPlugin injection. I'm wondering why I need to take the .AsImplementedInterfaces() out to make this work. I would prefer to use interfaces because I'm using MEF to import IControllers from other assemblies at runtime.
Update
Thanks to japonex (see comments below) I've updated my solution. Here's what I did to get everything working.
First my project has its own controllers, and I then use MEF to import controllers from other assemblies.
Controllers for my current project must be registered without the .AsImplementedInterfaces() call, so like so
builder.RegisterControllers(typeof(MvcApplication).Assembly).InstancePerRequest();
This will put the controllers into Autofac using the type instead of as an interface (MyProject.Controllers.HomeController instead of System.Web.Mvc.IController).
Next in my plugin project I simply had to export the types instead of as an interface.
So I use this
[Export]
[PartCreationPolicy(CreationPolicy.NonShared)]
public class HomeController : PluginController
Instead of this
[Export(typeof(IController))]
[PartCreationPolicy(CreationPolicy.NonShared)]
public class HomeController : PluginController
Notice the difference in the Export attribute.
Next I set the current DependencyResolver to the AutofacDependencyResolver.
Last, but not least, I created a custom ControllerFactory to create the controllers. Technically this isn't needed, since I'm no longer using interfaces, but I have code to check the status of the controller before creating it. This allows me to easily enable/disable a plugin from an admin area.
So the root of the problem is that Autofac needed types instead of interfaces to resolve properly. I'm sure this could be done with interfaces, but this solution works for me. The only real reason I would have wanted to use interfaces is because I could then ask for all controllers from Autofac without knowing their type.
public class MyControllerFactory : DefaultControllerFactory
{
private readonly IContainer _container;
public PortalControllerFactory(IContainer container)
{
_container = container;
}
public override IController CreateController(System.Web.Routing.RequestContext requestContext, string controllerName)
{
Type controllerType = GetControllerType(requestContext, controllerName);
if(controllerType == null)
{
throw new HttpException(404, ErrorMessages.Http404);
}
IPlugin plugin = PluginManager.Current.GetPlugin(controllerType);
if (plugin != null && plugin.Status != Common.Enums.PluginStatus.Enabled)
{
//the controller/plugin is disabled so modify the route data and return the controller
RouteData data = new RouteData();
data.Values.Add("controller", "plugin");
data.Values.Add("action", "disabled");
data.Values.Add("plugin", plugin.Name);
requestContext.RouteData = data;
return ViewRenderer.CreateController<Project.Controllers.PluginController>(data);
}
var controller = ((AutofacDependencyResolver)DependencyResolver.Current).RequestLifetimeScope.Resolve(controllerType);
return controller as IController;
}
}

When you use .AsImplementedInterfaces you're saying that for each concrete type, Autofac registers this type for each interface implementation.
So, you're registering all controllers in your Assembly to IController and propably because you don't have any rule (keyed or named registration) to decide which concrete type return, Autofac probably returns the last registration for IController.
Try call container.Resolve and see what you get.
Consider that if you have:
public class HomeController : BaseController
{
public HomeController(IPlugin plugin)
{
}
}
and
public class Home2Controller : BaseController
{
public Home2Controller(IPlugin plugin)
{
}
}
HomeController will be registered to IController and the
Home2Controller also will be registered to IController.
And I think the default behavior of Autofac is to use the last registration if you don't use any kind of rule (keyed or named registration)

Make sure that the controller has a parameterless public constructor error

I have followed this tutorial which has worked great, until I modified my DbContext to have an additional constructor. I am now having issues with the resolution and not sure what to do to fix this. Is there an easy way to force it to grab the parameterless constructor or I am approaching this incorrectly?
DbContext with two constructors:
public class DashboardDbContext : DbContext
{
public DashboardDbContext() : base("DefaultConnection") { }
public DashboardDbContext(DbConnection dbConnection, bool owns)
: base(dbConnection, owns) { }
}
SiteController constructor:
private readonly IDashboardRepository _repo;
public SiteController(IDashboardRepository repo)
{
_repo = repo;
}
Repository:
DashboardDbContext _context;
public DashboardRepository(DashboardDbContext context)
{
_context = context;
}
UnityResolver code:
public class UnityResolver : IDependencyResolver
{
private readonly IUnityContainer _container;
public UnityResolver(IUnityContainer container)
{
_container = container;
}
public object GetService(Type serviceType)
{
try
{
return _container.Resolve(serviceType);
}
catch (ResolutionFailedException)
{
return null;
}
}
public IEnumerable<object> GetServices(Type serviceType)
{
try
{
return _container.ResolveAll(serviceType);
}
catch (ResolutionFailedException)
{
return new List<object>();
}
}
public IDependencyScope BeginScope()
{
var child = _container.CreateChildContainer();
return new UnityResolver(child);
}
public void Dispose()
{
_container.Dispose();
}
}
WebApiConfig:
var container = new UnityContainer();
container.RegisterType<IDashboardRepository, DashboardRepository>(new HierarchicalLifetimeManager());
config.DependencyResolver = new UnityResolver(container);
Error from WebApi Call:
System.InvalidOperationException: An error occurred when trying to create a controller of type 'SiteController'. Make sure that the controller has a parameterless public constructor.
at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType)
at System.Web.Http.Controllers.HttpControllerDescriptor.CreateController(HttpRequestMessage request)
at System.Web.Http.Dispatcher.HttpControllerDispatcher.SendAsyncCore(HttpRequestMessage request, CancellationToken cancellationToken)
at System.Web.Http.Dispatcher.HttpControllerDispatcher.<SendAsync>d__0.MoveNext()
InnerException: System.ArgumentException: Type 'Dashboard.Web.Controllers.SiteController' does not have a default constructor.
at System.Linq.Expressions.Expression.New(Type type)
at System.Web.Http.Internal.TypeActivator.Create[TBase](Type instanceType)
at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.GetInstanceOrActivator(HttpRequestMessage request, Type controllerType, Func`1& activator)
at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType)
The tutorial was great and has been working well for me up until I added the second constructor.

What's happening is that you're bitten by this problem. Basically, what happened is that you didn't register your controllers explicitly in your container. Unity tries to resolve unregistered concrete types for you, but because it can't resolve it (caused by an error in your configuration), it return null. It is forced to return null, because Web API forces it to do so due to the IDependencyResolver contract. Since Unity returns null, Web API will try to create the controller itself, but since it doesn't have a default constructor it will throw the "Make sure that the controller has a parameterless public constructor" exception. This exception message is misleading and doesn't explain the real cause.
You would have seen a much clearer exception message if you registered your controllers explicitly, and that's why you should always register all root types explicitly.
But of course, the configuration error comes from you adding the second constructor to your DbContext. Unity always tries to pick the constructor with the most arguments, but it has no idea how to resolve this particular constructor.
So the real cause is that you are trying to use Unity's auto-wiring capabilities to create the DbContext. DbContext is a special type that shouldn't be auto-wired. It is a framework type and you should therefore fallback to registering it using a factory delegate:
container.Register<DashboardDbContext>(
new InjectionFactory(c => new DashboardDbContext()));

In my case, it was because of exception inside the constructor of my injected dependency (in your example - inside DashboardRepository constructor). The exception was caught somewhere inside MVC infrastructure. I found this after I added logs in relevant places.

I had the same issue and I resolved it by making changes in the UnityConfig.cs file In order to resolve the dependency issue in the UnityConfig.cs file you have to add:
public static void RegisterComponents()
{
var container = new UnityContainer();
container.RegisterType<ITestService, TestService>();
DependencyResolver.SetResolver(new UnityDependencyResolver(container));
}

I had the same problem. I googled it for two days. At last I accidentally noticed that the problem was access modifier of the constructor of the Controller.
I didn’t put the public key word behind the Controller’s constructor.
public class MyController : ApiController
{
private readonly IMyClass _myClass;
public MyController(IMyClass myClass)
{
_myClass = myClass;
}
}
I add this experience as another answer maybe someone else made a similar mistake.

Sometimes because you are resolving your interface in ContainerBootstraper.cs it's very difficult to catch the error. In my case there was an error in resolving the implementation of the interface I've injected to the api controller. I couldn't find the error because I have resolve the interface in my bootstraperContainer like this:
container.RegisterType<IInterfaceApi, MyInterfaceImplementaionHelper>(new ContainerControlledLifetimeManager());
then I've adde the following line in my bootstrap container : container.RegisterType<MyController>();
so when I compile the project , compiler complained and stopped in above line and showed the error.

If you are using UnityConfig.cs to resister your type's mappings like below.
public static void RegisterTypes(IUnityContainer container)
{
container.RegisterType<IProductRepository, ProductRepository>();
}
You have to let the know **webApiConfig.cs** about Container
config.DependencyResolver = new Unity.AspNet.WebApi.UnityDependencyResolver(UnityConfig.Container);

I really, really hope this answer helps someone else from wasting a day and a half of messing around with; Ninject, MVC design pattern, Global.asax, Web Common files etc etc.
The error itself was completely misleading in my case.
My entire application was working sound with the exception of when I called one particualr controller lets call TestController.
Test controller was using Ninject to inject an interface lets call ITest like so -
public class TestController : ApiController
{
private readonly ITest _test;
public TestController (ITest test)
{
_test= test;
}
I was making a simple GET request to one of the methods in TestController and was getting the aforementioned error for this threads question.
I eventually boiled it down to the error only occuring when ITest was injected as a parameter (as I tested a different interface and it worked soundly!)
This led me to check the Test class and realsied that I had injected an instance of itself into it! Like so -
public class Test: ITest
{
private readonly ITest_test;
public Test(ITest test)
{
_test = test;
}
Thus resulting in the entire call falling over as an unhandled exception and returning a completely bizarre error that didn't help me at all!

If you have an interface in your controller
public myController(IXInterface Xinstance){}
You must register them to Dependency Injection container.
container.Bind<IXInterface>().To<XClass>().InRequestScope();

I've got this error when I accidentally defined a property as a specific object type, instead of the interface type I have defined in UnityContainer.
For example:
Defining UnityContainer:
var container = new UnityContainer();
container.RegisterInstance(typeof(IDashboardRepository), DashboardRepository);
config.DependencyResolver = new UnityResolver(container);
SiteController (the wrong way - notice repo type):
private readonly DashboardRepository _repo;
public SiteController(DashboardRepository repo)
{
_repo = repo;
}
SiteController (the right way):
private readonly IDashboardRepository _repo;
public SiteController(IDashboardRepository repo)
{
_repo = repo;
}

In my case, Unity turned out to be a red herring. My problem was a result of different projects targeting different versions of .NET. Unity was set up right and everything was registered with the container correctly. Everything compiled fine. But the type was in a class library, and the class library was set to target .NET Framework 4.0. The WebApi project using Unity was set to target .NET Framework 4.5. Changing the class library to also target 4.5 fixed the problem for me.
I discovered this by commenting out the DI constructor and adding default constructor. I commented out the controller methods and had them throw NotImplementedException. I confirmed that I could reach the controller, and seeing my NotImplementedException told me it was instantiating the controller fine. Next, in the default constructor, I manually instantiated the dependency chain instead of relying on Unity. It still compiled, but when I ran it the error message came back. This confirmed for me that I still got the error even when Unity was out of the picture. Finally, I started at the bottom of the chain and worked my way up, commenting out one line at a time and retesting until I no longer got the error message. This pointed me in the direction of the offending class, and from there I figured out that it was isolated to a single assembly.

Install Nuget Package Unit.WebAP instead of Unity.MVC5 Make sure the correct unity package is installed using nuget
I Installed Unity.MVC5 and was facing similar exception "parameterless constructor"
public static void RegisterComponents()
{
var container = new UnityContainer();
// register all your components with the container here
// it is NOT necessary to register your controllers
// e.g. container.RegisterType<ITestService, TestService>();
container.RegisterType<ICar, Tesla>();
GlobalConfiguration.Configuration.DependencyResolver = new UnityDependencyResolver(container);
}

Exception is: InvalidOperationException - The current type, is an interface and cannot be constructed. Are you missing a type mapping?

In my bootstrapper:
namespace Conduit.Mam.ClientServices.Common.Initizliaer
{
public static class Initializer
{
private static bool isInitialize;
private static readonly object LockObj = new object();
private static IUnityContainer defaultContainer = new UnityContainer();
static Initializer()
{
Initialize();
}
public static void Initialize()
{
if (isInitialize)
return;
lock (LockObj)
{
IUnityContainer container = defaultContainer;
//registering Unity for MVC
DependencyResolver.SetResolver(new UnityDependencyResolver(container));
//registering Unity for web API
// GlobalConfiguration.Configuration.DependencyResolver = new Unity.WebApi.UnityDependencyResolver(container);
#region managers
container.RegisterType<ISettingsManager, SettingsManager>();
container.RegisterType<IMamDataManager, MamDataManager>();
container.RegisterType<IAppsDataManager, AppsDataManager>();
#endregion
if (!isInitialize)
{
isInitialize = true;
}
}
}
}
}
in my controller's code:
ISettingsManager sm = mUnityContainer.Resolve<ISettingsManager>();
hovering on mUnityContainer I see ISettingsManager is mapped to SettingsManager
but then I get the error:
Exception is: InvalidOperationException - The current type, is an
interface and cannot be constructed. Are you missing a type mapping?
I have also tried
ISettingsManager sm = (ISettingsManager)mUnityContainer.Resolve<>(typeof(ISettingsManager));
but no use

Just for others (like me) who might have faced the above error. The solution in simple terms.
You might have missed to register your Interface and class (which implements that inteface) registration in your code.
e.g if the error is
"The current type, xyznamespace. Imyinterfacename, is an interface and cannot be constructed. Are you missing a type mapping?"
Then you must register the class which implements the Imyinterfacename in the UnityConfig class in the Register method. using code like below
container.RegisterType<Imyinterfacename, myinterfaceimplclassname>();

You are incorrectly using Dependency Injection. The proper way is to have your controllers take the dependencies they need and leave to the dependency injection framework inject the concrete instances:
public class HomeController: Controller
{
private readonly ISettingsManager settingsManager;
public HomeController(ISettingsManager settingsManager)
{
this.settingsManager = settingsManager;
}
public ActionResult Index()
{
// you could use the this.settingsManager here
}
}
As you can see in this example the controller doesn't know anything about the container. And that's how it should be.
All the DI wiring should happen in your Bootstraper. You should never use container.Resolve<> calls in your code.
As far as your error is concerned, probably the mUnityContainer you are using inside your controller is not the same instance as the one constructed in your Bootstraper. But since you shouldn't be using any container code in your controllers, this shouldn't be a problem anymore.

In my case, I was getting this error despite registering an existing instance for the interface in question.
Turned out, it was because I was using Unity in WebForms by way of the Unity.WebForms Nuget package, and I had specified a Hierarchical Lifetime manager for the dependency I was providing an instance for, yet a Transient lifetime manager for a subsequent type that depended on the previous type - not usually an issue - but with Unity.WebForms, the lifetime managers work a little differently... your injected types seem to require a Hierarchical lifetime manager, but a new container is still created for every web request (because of the architecture of web forms I guess) as explained excellently in this post.
Anyway, I resolved it by simply not specifying a lifetime manager for the types/instances when registering them.
i.e.
container.RegisterInstance<IMapper>(MappingConfig.GetMapper(), new HierarchicalLifetimeManager());
container.RegisterType<IUserContext, UserContext>(new TransientLifetimeManager());
becomes
container.RegisterInstance<IMapper>(MappingConfig.GetMapper());
container.RegisterType<IUserContext, UserContext>();
So that IMapper can be resolved successfully here:
public class UserContext : BaseContext, IUserContext
{
public UserContext(IMapper _mapper) : base(_mapper)
{
}
...
}

In my case, I have used 2 different context with Unitofwork and Ioc container so i see this problem insistanting while service layer try to make inject second repository to DI. The reason is that exist module has containing other module instance and container supposed to gettng a call from not constractured new repository.. i write here for whome in my shooes

May be You are not registering the Controllers.
Try below code:
Step 1.
Write your own controller factory class
ControllerFactory :DefaultControllerFactory by implementing defaultcontrollerfactory
in models folder
public class ControllerFactory :DefaultControllerFactory
{
protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
{
try
{
if (controllerType == null)
throw new ArgumentNullException("controllerType");
if (!typeof(IController).IsAssignableFrom(controllerType))
throw new ArgumentException(string.Format(
"Type requested is not a controller: {0}",
controllerType.Name),
"controllerType");
return MvcUnityContainer.Container.Resolve(controllerType) as IController;
}
catch
{
return null;
}
}
public static class MvcUnityContainer
{
public static UnityContainer Container { get; set; }
}
}
Step 2:Regigster it in BootStrap:
inBuildUnityContainer method
private static IUnityContainer BuildUnityContainer()
{
var container = new UnityContainer();
// register all your components with the container here
// it is NOT necessary to register your controllers
// e.g. container.RegisterType<ITestService, TestService>();
//RegisterTypes(container);
container = new UnityContainer();
container.RegisterType<IProductRepository, ProductRepository>();
MvcUnityContainer.Container = container;
return container;
}
Step 3:
In Global Asax.
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
WebApiConfig.Register(GlobalConfiguration.Configuration);
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
AuthConfig.RegisterAuth();
Bootstrapper.Initialise();
ControllerBuilder.Current.SetControllerFactory(typeof(ControllerFactory));
}
And you are done

I had this problem, and the cause was that I had not added the Microsoft.Owin.Host.SystemWeb NuGet package to my project. Although the code in my startup class was correct, it was not being executed.
So if you're trying to solve this problem, put a breakpoint in the code where you do the Unity registrations. If you don't hit it, your dependency injection isn't going to work.

Below code will be helpful for you
public static IUnityContainer Initialise(IUnityContainer container = null)
{
if (container == null)
{
container = new UnityContainer();
}
container.RegisterType<ISettingsManager, SettingsManager>();
container.Resolve<SettingsManager>();
container.RegisterType<SettingsManagerController>(new InjectionProperty("_SettingManagerProvider", new ResolvedParameter<ISettingManager>()));
return container;
}

Make sure that the controller has a parameterless public constructor in Unity

I got this problem with the Controller:
An error occurred when trying to create a controller of type '*.WebMvc.Controllers.HomeController'. Make sure that the controller has a parameterless public constructor.
Find the solution for the ApiController, but didn't find anything about normal Controller.
Created new MVC 4 project from scratch.
HomeController.cs:
public class HomeController : Controller
{
private IAccountingUow _uow;
public HomeController(IAccountingUow uow)
{
_uow = uow;
}
UnityDependencyResoler.cs:
public class UnityDependencyResolver : IDependencyResolver
{
private IUnityContainer _container;
public UnityDependencyResolver(IUnityContainer container)
{
_container = container;
RegisterTypes();
}
public object GetService(Type serviceType)
{
try
{
return _container.Resolve(serviceType);
}catch
{
return null;
}
}
public IEnumerable<object> GetServices(Type serviceType)
{
try
{
return _container.ResolveAll(serviceType);
}catch
{
return null;
}
}
private void RegisterTypes()
{
_container.RegisterType<IAccountingUow, AccountingUow>();
}
}
Global.asax
protected void Application_Start()
{
//Omitted
DependencyResolver.SetResolver( new UnityDependencyResolver( new UnityContainer()));
}
Debugged and found out, that there are even no attempts to resolve IAccountingUow.
What i'm doing wrong?
Thinking about it whole day.

Found where is the issue. Maybe some one will face the same.
The problem is that Unity could not resolve the IAccountingUow, because of hierarchical dependancy on interfaces.
AccountingUow class has two contuctors
public AccountingUow( IRepositoryProvider repositoryProvider)
{
Init(repositoryProvider);
}
public AccountingUow()
{
Init( new RepositoryProvider(new RepositoryFactories()) );
}
Dependency Resolver is not smart enought to take the default parametless contructor. It tries to take interface dependant contructor and fails to resolve it, cause there are no rules for resolving it.
I commented out interface dependant constructor and everything worked fine.
I will post later resolver for the first contructor, maybe someone will use it.

This can also be due to an exception in the parameter-injected constructor of the outer type that is being resolved. The dependencies of that type's constructor might be getting resolved successfully, but if there is an exception in the outer constructor, Unity will report it as "Type Test.Controllers.MyControllerWithInjectedDependencies does not have a default constructor".

Install Nuget Package Unit.WebAP instead of Unity.MVC5 Make sure the correct unity package is installed using nuget
I Installed Unity.MVC5 and was facing similar exception "parameterless constructor"