How to use DI container when OwinStartup

Question

It's a Web API 2 project.

When I implement DI using Ninject, I got an error message

An error occurred when trying to create a controller of type 'TokenController'. Make sure that the controller has a parameterless public constructor.

[assembly: OwinStartup(typeof(Web.Startup))]

namespace Web
{
    public partial class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            ConfigureAuth(app);
            ConfigureWebApi(app);
        }
    }
}

public class TokenController : ApiController
{

    private IUserService _userService;

    public TokenController(IUserService userService)
    {
        this._userService = userService;
    }

    [Route("api/Token")]
    public HttpResponseMessage PostToken(UserViewModel model)
    {
        if (_userService.ValidateUser(model.Account, model.Password))
        {
            ClaimsIdentity identity = new ClaimsIdentity(Startup.OAuthBearerOptions.AuthenticationType);
            identity.AddClaim(new Claim(ClaimTypes.Name, model.Account));
            AuthenticationTicket ticket = new AuthenticationTicket(identity, new AuthenticationProperties());
            var currentUtc = new SystemClock().UtcNow;
            ticket.Properties.IssuedUtc = currentUtc;
            ticket.Properties.ExpiresUtc = currentUtc.Add(TimeSpan.FromMinutes(30));
            return new HttpResponseMessage(HttpStatusCode.OK)
            {
                Content = new ObjectContent<object>(new
                {
                    UserName = model.Account,
                    AccessToken = Startup.OAuthBearerOptions.AccessTokenFormat.Protect(ticket)
                }, Configuration.Formatters.JsonFormatter)
            };
        }

        return new HttpResponseMessage(HttpStatusCode.BadRequest);
    }
}

When I add <add key="owin:AutomaticAppStartup" value="false" /> to web.config

Ninject works fine, but Startup.OAuthBearerOptions.AccessTokenFormat becomes to null

How to use DI container with OWIN?

UPDATE

Implement IDependencyResolver and use the WebAPI Dependency Resolver as below

public void ConfigureWebApi(IAppBuilder app)
{
    HttpConfiguration config = new HttpConfiguration();

    config.DependencyResolver = new NinjectDependencyResolver(NinjectWebCommon.CreateKernel());

    app.UseWebApi(config);
}

NinjectDependencyResolver

In Simple Injector case

public void ConfigureWebApi(IAppBuilder app)
{
    HttpConfiguration config = new HttpConfiguration();

    var container = new Container();
    container.Register<IUserService, UserService>();
    config.DependencyResolver = new SimpleInjectorWebApiDependencyResolver(container);

    app.UseWebApi(config);
}

SimpleInjectorWebApiDependencyResolver

Is there a reason why you can't add an empty constructor to your controller? — Nikolai Samteladze
@NikolaiSamteladze I have already implement dependency inject in empty constructor, I just want to know how to use DI container in this case — E-Cheng Liu
There is a project which provides this support, but maybe you'll have to write the adapter for ninject yourself as it provides an out of the box implementation for autofac only. — Mat J
Try it and if it answers your question, come back and let me know, I'll make it an answer. Till then let's see if anyone can provide any better way. — Mat J

Maxime Rouiller Maxime Rouiller · Accepted Answer · 2013-12-05T14:05:03

You might want to take a look at this blog post.

It's using Unity but it should end-up being the same.

Basically, use the WebAPI Dependency Resolver. Make sure that everything is mapped properly and it should be fine.

If after setting up your DI you still have problem with your OAuth token, let me know.

Cheers

How to use DI container when OwinStartup

3 Answers