Ninject not working in Web API contructor in ASP.NET MVC 4 - asp.net-mvc-4

Question

I am new to ASP.NET Web API.
I have upgraded my ASP.NET MVC 3 project to ASP.NET MVC 4 by using this tutorial.
Now I am trying to use Web Api here, as you can see I am trying to use ninject here, but when I declare ProductsController constructor in such a way, this does not work.
public class ProductsController : ApiController
{
private readonly IProductService _productService;
public ProductsController(IProductService productService)
{
this._productService = productService;
}
public List<Product> GetProducts()
{
return _productService.GetAllProducts();
}
}
Please help me on this.
If I add this constructor there is no call made to Web Api methods, I confirmed this by using breakpoints and it makes call otherwise.
Browser shows an xml error which reads
<Error><Message>An error has occurred.</Message></Error>
My NinjectWebCommon.cs class code is
[assembly: WebActivator.PreApplicationStartMethod(typeof(Web.App_Start.NinjectWebCommon), "Start")]
[assembly: WebActivator.ApplicationShutdownMethodAttribute(typeof(Web.App_Start.NinjectWebCommon), "Stop")]
namespace Web.App_Start
{
public static class NinjectWebCommon
{
private static readonly Bootstrapper bootstrapper = new Bootstrapper();
/// <summary>
/// Starts the application
/// </summary>
public static void Start()
{
DynamicModuleUtility.RegisterModule(typeof(OnePerRequestHttpModule));
DynamicModuleUtility.RegisterModule(typeof(NinjectHttpModule));
bootstrapper.Initialize(CreateKernel);
}
/// <summary>
/// Stops the application.
/// </summary>
public static void Stop()
{
bootstrapper.ShutDown();
}
/// <summary>
/// Creates the kernel that will manage your application.
/// </summary>
/// <returns>The created kernel.</returns>
private static IKernel CreateKernel()
{
var kernel = new StandardKernel();
kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();
RegisterServices(kernel);
return kernel;
}
/// <summary>
/// Load your modules or register your services here!
/// </summary>
/// <param name="kernel">The kernel.</param>
private static void RegisterServices(IKernel kernel)
{
kernel.Bind<IProductService>().To<ProductService>();
}
}
}

Answer 1

You can follow these steps to get WebApi and Ninject up and running:
1 Create a new WebApi project
2 Add the following code for a field and a constructor to the default ValuesController:
private IFooService _foo;
public ValuesController(IFooService foo)
{
_foo = foo;
}
3 Create an interface IFooService and a class FooService
public interface IFooService
{
}
public class FooService : IFooService
{
}
4 Run the following command in your Nuget Packag Manager Console to install Ninject
Install-Package Ninject.MVC3
5 Add the following binding to App_Start\NinjectWebCommon.cs in method RegisterServices(IKernel kernel)
kernel.Bind<IFooService>().To<FooService>().InRequestScope();
In your code, you are probably not calling the NInject configuration at the right moment. When you use the Nuget package you get the following lines at the top of your Ninject file:
[assembly: WebActivator.PreApplicationStartMethod(typeof(WebApiNinjectTest.App_Start.NinjectWebCommon), "Start")]
[assembly: WebActivator.ApplicationShutdownMethodAttribute(typeof(WebApiNinjectTest.App_Start.NinjectWebCommon), "Stop")]
These lines will make sure your code is executed at the right time.

Answer 2

Update : A super awesome explanation at : http://www.strathweb.com/2012/05/using-ninject-with-the-latest-asp-net-web-api-source/, Now I no longer have to use ProductsController(): this(new ProductService()).
Ah alas got this working now :)
Here is what I did...
I have two constructor of each of my WebApiController. For example for my ProductsController now the constructor I needed to define were as follows...
public class ProductsController : ApiController
{
private readonly IProductService _productService;
public ProductsController(): this(new ProductService())
{
}
public ProductsController(IFolderService productService)
{
this._polderService = productService;
}
public List<Product> GetProducts()
{
return _productService.GetAllProducts();
}
}
:)