Renew access token method

gistfile1.txt

namespace Com.Example.Controllers
{
    [Authorize]
    public class HomeController : Controller
    {
        public HomeController()
        {
        }
        
        //Use Refresh Token to generate new Access Token
        public async Task<AccessTokenVM> GetNewAccessToken() {
            
            var client = new DiscoveryClient("http://localhost:5000");

            var disco = await client.GetAsync();
            if (disco.IsError) throw new Exception(disco.Error);

            //Connect to token endpoint (Security Server)
            var tokenClient = new TokenClient(disco.TokenEndpoint, "<clientId>", "<clientSecret>");
            //Get Refresh Token
            var rt = await HttpContext.Authentication.GetTokenAsync("refresh_token");
            //Get new Access Token
            var tokenResult = await tokenClient.RequestRefreshTokenAsync(rt);

            if (!tokenResult.IsError)
            {
                var old_id_token = await HttpContext.Authentication.GetTokenAsync("id_token");
                var new_access_token = tokenResult.AccessToken;
                var new_refresh_token = tokenResult.RefreshToken;

                //Store the tokens
                var tokens = new List<AuthenticationToken>();
                tokens.Add(new AuthenticationToken { Name = OpenIdConnectParameterNames.IdToken, Value = old_id_token });
                tokens.Add(new AuthenticationToken { Name = OpenIdConnectParameterNames.AccessToken, Value = new_access_token });
                tokens.Add(new AuthenticationToken { Name = OpenIdConnectParameterNames.RefreshToken, Value = new_refresh_token });

                var expiresAt = DateTime.UtcNow + TimeSpan.FromSeconds(tokenResult.ExpiresIn);
                tokens.Add(new AuthenticationToken { Name = "expires_at", Value = expiresAt.ToString("o", CultureInfo.InvariantCulture) });
                var info = await HttpContext.Authentication.GetAuthenticateInfoAsync("Cookies");
                info.Properties.StoreTokens(tokens);
                await HttpContext.Authentication.SignInAsync("Cookies", info.Principal, info.Properties);

                return new AccessTokenVM { Success = true, AccessToken = new_access_token, ExpiresAt = expiresAt};
            }
            return new AccessTokenVM { Success = false, Error = tokenResult.Error };
        }

        //Return the initial SPA (single page application) view
        public async Task<ActionResult> Index()
        {
            ...
        }
        
        [HttpPost]
        public async Task LogOff()
        {
            ...
        }
    }
}