public async Task <ResponseModelBase> DoLogin([FromBody] LoginInfoRequestModel model)
        {
            if (!ModelState.IsValid)
            {
                return(ErrorModel.Of("invalid_request"));
            }

            try
            {
                var resp = await ldb.DoLogin(model.EmailAddress, model.Password);

                if (resp == null)
                {
                    return(ErrorModel.Of("unknown_error"));
                }
                return(Models.OkModel.Of(new UserSessionResponseModel(resp), "logged_in"));
            }
            catch (ArgumentException e)
            {
                return(ErrorModel.Of(e.Message));
            }
        }