private void RegisterClient(NotifyClientAbstraction request, string userContextId, Notification notification)
        {
            foreach (var userId in request.UsersId)
            {
                var client = new Client(userId,
                                        userContextId);
                _clientRepository.Add(client);

                RegisterClientNotification(client.Id, notification.Id, userContextId);
            }
        }
        private void RegisterNotification(NotifyClientAbstraction request,
                                          string owner,
                                          int applicationId,
                                          string userContextId,
                                          out Notification notification)
        {
            notification = new Notification(request.Title,
                                            request.Message,
                                            owner,
                                            applicationId,
                                            userContextId);

            notification = _notificationRepository.Add(notification);
        }