Design pattern for a base controller with dependecy injection - MVC 3 + Ninject

Question

I've got this pattern

public abstract class BaseController : Controller
{
    readonly RepositoryFactory _rep;
    protected RepositoryFactory rep
    {
        get
        {
            return _rep;
        }
    }

    readonly ManageRoles _man;

    readonly ElementAvailableForUser _env;
    protected ElementAvailableForUser env
    {
        get
        {
            return _env;
        }
    }

    public BaseController()
      : this(DependencyResolver.Current.GetService<RepositoryFactory>(),
             DependencyResolver.Current.GetService<ManageRoles>(),
             DependencyResolver.Current.GetService<ElementAvailableForUser>()) { }

    public BaseController(RepositoryFactory rep, ManageRoles man, ElementAvailableForUser env)
    {
        _rep = rep;
        _man = man;
        _env = env;
    }
}

so I am able to do something like this

public class HomeController : BaseController
{
    public ActionResult Index()
    {
        return View(rep.Offers.GetAll());
    }

    public ActionResult Sections()
    {
        return View(env);
    }
}

in all my controller. I'm sure this is antipattern for DI and IoC, so I thin a solution like this

public abstract class BaseController : Controller
{
    ...

    // removed empty constructor

    public BaseController(RepositoryFactory rep, ManageRoles man, ElementAvailableForUser env)
    {
        _rep = rep;
        _man = man;
        _env = env;
    }
}

public class HomeController : BaseController
{
    public HomeController(RepositoryFactory rep, ManageRoles man, ElementAvailableForUser env) : base(rep, man, env) { }

    ...
}

but this solution requires me to insert all dependencies in all controllers and update all constructor if I need a new global variable (like rep) or a new private variable for basecontroller (like man).

Which pattern should I follow and why?

Edit I found this question, and this, but still I can't understand which design patterns should I follow.

What makes you think there's a design pattern you should follow? — bzlm, Oct 12 '11 at 15:08

score 3 · Answer 1 · answered Oct 12 '11 at 15:33

It doesn't seem like you need the BaseController in this case. I think it would be easier (and more testable) to do something like this:

    public class HomeController : Controller
    {
        private readonly IRepository<Offers> _repository;
        private readonly RoleManager _roleManager;
        private readonly UserManager _userManager;

        public HomeController(IRepository<Offers> repository, RoleManager roleManager, UserManager userManager)
        {
            _repository = repository;
            _roleManager = roleManager;
            _userManager = userManager;
        }
    }

Then you could have your IoC container wire up all of those dependencies automatically for each controller.

Yes, this could be the case, but I need to populate the object in the same way for all the controller, and I do this in actionexecuting method of base controller. — Sig. Tolleranza, Oct 12 '11 at 15:45

score 0 · Answer 2 · answered Oct 12 '11 at 15:22

0

I don't think with the thin solution you need to always declare rep, man, and env. You could take advantage of default/optional parameters.

public BaseController(RepositoryFactory rep = null, ManageRoles man = null, ElementAvailableForUser env = null)
{
    _rep = rep;
    _man = man;
    _env = env;
}

Then you can use named parameter assignments:

public class HomeController : BaseController
{
    public HomeController(ManageRoles man) : base(man: man) { }

    ...
}

answered Oct 12 '11 at 15:22

Gary.S

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Yes, but in this case the IoC doesn't work and "man" results always null if has not been explicited declared in child controller. – Sig. Tolleranza Oct 12 '11 at 15:28

Design pattern for a base controller with dependecy injection - MVC 3 + Ninject

2 Answers2