MVC Controller inside ApiController with ControllerContext - asp.net-mvc

Question

Short story about what I am doing and why. I had been doing view to string conversion in Mvc project, but suddenly all project moved to the REST API. But I had to use razor engine to convert my view with all model data there, so I was trying to use directly from api, but it didn't work for me, so I decided to create a Mvc controller and call it directly from API, what is missing, only ControllerContext, because when I create controller directly, it appears to be null.
Here is my Api controller
public class AttachmentController : ApiController
{
[HttpGet]
public async Task<IHttpActionResult> Get(long id)
{
try
{
var mvcController = new AttachmentMvcController();
var result = await mvcController.Get();
return Ok(result);
}
catch (Exception e)
{
return InternalServerError(e);
}
}
}
and this is my Mvc Controller
public class AttachmentMvcController : Controller
{
public AttachmentMvcController(){ }
public async Task<byte[]> Get()
{
string result;
// !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
// HERE IS MY PROBLEM, I NEED this.ControllerContext, but it is null !!!
if (ControllerContext == null)
{
// create it and do task
var factory = DependencyResolver.Current.GetService<IControllerFactory>() ?? new DefaultControllerFactory();
AttachmentMvcController controller = factory.CreateController(ctx.RequestContext, "AttachmentMvc") as AttachmentMvcController;
RouteData route = new RouteData();
route.Values.Add("action", "ActionThatUsesControllerContext"); // ActionName, but it not required
ControllerContext newContext = new ControllerContext(new HttpContextWrapper(System.Web.HttpContext.Current), route, controller);
controller.ControllerContext = newContext;
result = await controller.ActionThatUsesControllerContext(id);
}
else
{
result = await this.ActionThatUsesControllerContext(id);
}
return result;
}
private async Task<byte[]> ActionThatUsesControllerContext()
{
{....}
// here I am trying to use helper that uses that controller context
string viewAsString = ControllerContext.RenderPartialToString("MyView", requestModel);
{....}
}
}
If anyone has idea how to get that ControllerContext or any other ways to get my razor engine render view inside ApiController, please share.