Unity how to pass Request in Controller's constructor from Unity - asp.net-mvc

Question

The old controller code with Concrete dependencies:
public SomeController: Controller
{
public SomeController()
{
}
public ActionResult Default()
{
**Something something = new Something(Request.ServerVariables["HTTP_X_REWRITE_URL"].ToString());**
something.SomeMethod();
}
}
The new Controller code with TDD focus:
public SomeControllerNew: Controller
{
private readonly ISomething _something;
public SomeControllerNew(ISomething something)
{
_something = something;
}
public ActionResult Default()
{
_something.SomeMethod();
}
}
PROBLEM:
Now in new TDD approach i need to invoke constructor where I am registering the Interface. I have put it in UnityBootstraper common file, Something like:
var container = new UnityContainer();
container.RegisterType();
**Something something = new Something(Request.ServerVariables["HTTP_X_REWRITE_URL"].ToString());**
something.SomeMethod();
This is not working here. Error is quite clear:
Object reference required for non-static field, method, property 'System.Web.Mvc.Controller.Request.get'.
I can't figure out how i can access http request here in UnityBootstrapper?
Edit:
Trying to do all this in RegisterRoutes.
public class RouteConfig
{
public static void RegisterRoutes(RouteCollection routes)
{
DependencyResolver.SetResolver(new Unity.Mvc3.UnityDependencyResolver(UnityBootstrapper.Initialise()));
var container = new UnityContainer();
container.RegisterType<ISometing, Something>();
}
}

Answer 1

One way to do it is to create an abstract factory like this:
public interface ISomethingFactory
{
ISomething Create(string url);
}
public class SomethingFactory : ISomethingFactory
{
public ISomething Create(string url)
{
return new Something(url);
}
}
And make your controller depend on it like this:
public class SomeControllerNew: Controller
{
private readonly ISomething _something;
public SomeControllerNew(ISomethingFactory somethingFactory)
{
_something = somethingFactory.Create(Request.ServerVariables["HTTP_X_REWRITE_URL"].ToString();
}
public ActionResult Default()
{
_something.SomeMethod();
}
}
A better approach (IMO) is to use a custom Controller Factory instead of using the Dependency Resolver like this:
public class CustomFactory : DefaultControllerFactory
{
public override IController CreateController(RequestContext requestContext, string controllerName)
{
var request = requestContext.HttpContext.Request; //Here we have access to the request
if (controllerName == "Some") //Name of controller
{
//Use the container to resolve and return the controller.
//When you resolve, you can use ParameterOverride to specify the value of the string dependency that you need to inject into Something
}
return base.CreateController(requestContext, controllerName);
}
}
This way you don't have to introduce the ISomethingFactory, and your controller would still depend on ISomething directly.
You would need to tell the MVC framework about this custom controller factory like this (in Application_Start):
ControllerBuilder.Current.SetControllerFactory(new CustomFactory());