public ActionResult Index()
        {
            var spContext = SharePointContextProvider.Current.GetSharePointContext(HttpContext);

            using (var clientContext = spContext.CreateUserClientContextForSPHost())
            {
                if (clientContext != null)
                {
                    ViewBag.SiteName = _cache.GetFromCache <string>("SiteTitle", () =>
                    {
                        return(GetSiteTitle(clientContext));
                    });
                }
            }

            return(View());
        }