public override void UserSignInEventHandler(object sender, UserSignInEventArgs e)
        {
            if (e == null)
            {
                return;
            }
            if (e.SiteUser == null)
            {
                return;
            }

            // do nothing
            log.Debug("DoNothingUserSignInHandlerProvider called for user " + e.SiteUser.Email);
        }
 public abstract void UserSignInEventHandler(
     object sender,
     UserSignInEventArgs e);