HomeController_extract01.cs

using OfficeDevPnP.Core.WebAPI;

//...

[SharePointContextFilter]
public ActionResult Register()
{
   try
   {
       // Register the BusinessDocuments API
       WebAPIHelper.RegisterWebAPIService(this.HttpContext, "/api/BusinessDocuments");
       return Json(new { message = "Web API registered" });
   }
   catch (Exception ex)
   {
       return Json(ex);
   }
}