/// <summary> /// Validate refresh token /// </summary> /// <returns>if token is valid - (true, null), otherwise (false, [reason])</returns> private async Task <bool> ValidaateRefreshToken(string userName, string sessionId, string refreshTokenToVerify) { IAuthToken savedRefreshToken = await _userStore.GetRefreshToken(userName, sessionId); //retrieve the refresh token from data storage if (savedRefreshToken == null || savedRefreshToken.Token != refreshTokenToVerify || savedRefreshToken.ExpireDate < DateTime.UtcNow) { return(false); } return(true); }