public async Task <IActionResult> Index()
        {
            string accessToken = "";

            using (var httpClient = _httpClientFactory.CreateClient())
            {
                var dictionary = _configuration.GetSection("AzureAd").GetChildren()
                                 .Select(item => new KeyValuePair <string, string>(item.Key, item.Value))
                                 .ToDictionary(x => x.Key, x => x.Value);

                dictionary["userName"] = User.Identity.Name;

                try
                {
                    //obtain an access token if it exists in the token cache.
                    //if no access token exists in the token cache an error will be thrown
                    accessToken = await _tokenHandler.GetAccessTokenSilently(dictionary);
                }
                catch (Exception e)
                {
                    //catches error thrown if no token exists in the token cache. Will cause a redirect to sign the user in
                    //and run through the authN process to ensure an access token is loaded into the token cache
                    return(RedirectToAction("SignIn", "Account"));
                }

                //uses access token to call ModernAuth_API
                httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", accessToken);
                var response = await httpClient.GetAsync(_configuration["apiURL"] + dictionary["userName"]);

                var responseContent = await response.Content.ReadAsStringAsync();

                //Deserializes user data returned from Graph API, which is called by ModernAuth_API.
                var userBody = JsonConvert.DeserializeObject <User>(responseContent);

                return(View(userBody));
            }
        }