Unity - The current type is an interface and cannot be constructed. Generic repository DI

Question

I have generic repository:

public interface IRepository<T> where T : class
{
    void Add(T entity);
    void Update(T entity);
    void Delete(T entity);
    void Delete(Expression<Func<T, bool>> where);
    T GetById(long id);
    T GetById(string id);
    T Get(Expression<Func<T, bool>> where);
    IEnumerable<T> GetAll();
    IEnumerable<T> GetMany(Expression<Func<T, bool>> where);
}

And realized class:

public abstract class BaseRepository<T> where T : class 
{
    private ApplicationDbContext _context;
    private readonly IDbSet<T> dbset;

    protected BaseRepository(IDatabaseFactory databaseFactory)
    {
        DatabaseFactory = databaseFactory;
        dbset = _context.Set<T>();
    }

    protected IDatabaseFactory DatabaseFactory
    {
        get;
        private set;
    }

    protected ApplicationDbContext DataContext
    {
        get { return _context ?? (_context = DatabaseFactory.Get()); }
    }

    //methods below..
}

And I have UserRepository with interface:

public interface IUserRepository : IRepository<UserRepository>
{

}

public class UserRepository : BaseRepository<UserRepository>, IUserRepository
{
    public UserRepository(IDatabaseFactory databaseFactory) : base(databaseFactory)
    {

    }
}

And I'm using BaseController to get my Identity currentUser in any controller extended from Base:

BaseController :

public class BaseController : Controller
{
    protected readonly IUserRepository userRepository;
    public UserAccountModel currentUser { get; private set; }

    public BaseController(IUserRepository UserRepository)
    {
        this.userRepository = UserRepository;
    }

    //Initialize
}

And HomeController :

public class HomeController : BaseController
{
    protected readonly IUserRepository userRepository;

    public HomeController(IUserRepository UserRepository) : base(UserRepository)
    {
        this.userRepository = UserRepository;
    }

    //actions
}

I'm using Unity IoC, and my UnityConfig.cs looks like this:

private static void RegisterTypes(IUnityContainer container)
{
    container.RegisterType<IUnitOfWork, UnitOfWork>();
    container.RegisterType<IDatabaseFactory, DatabaseFactory>();
    container.RegisterType<ApplicationDbContext>();
    container.RegisterType<ApplicationSignInManager>();
    container.RegisterType<ApplicationUserManager>();

    container.RegisterType<IAuthenticationManager>(
            new InjectionFactory(c => HttpContext.Current.GetOwinContext().Authentication));

    container.RegisterType<IUserStore<ApplicationUser>, UserStore<ApplicationUser>>(
        new InjectionConstructor(typeof(ApplicationDbContext)));

    container.RegisterType(typeof(IRepository<>), typeof(BaseRepository<UserRepository>));
}

On run, I'm getting error:

The current type, ProjectName.Data.Repository.IUserRepository, is an interface and cannot be constructed. Are you missing a type mapping?

I think my problem is wrong type registration, but I'm already broke my head on it...

Jim Patterson Jim Patterson · Accepted Answer · 2016-12-13T17:23:39

Looks to me like you need a mapping between IUserRepository and UserRepository. e.g.:

container.RegisterType<IUserRepository, UserRepository>();

Unity - The current type is an interface and cannot be constructed. Generic repository DI

2 Answers