public BackendEventModel GetBackendEventModel(EventModel eventModel)
        {
            var backendEventModel = BackendEventModel.ConvertToBackendEventModel(eventModel);

            var owner = JsonConvert.DeserializeObject <BackendEventModel>(
                _redisUsersDatabase.StringGet(eventModel.Owner.Id));

            var visitors = new List <string>();

            if (eventModel.Visitors != null)
            {
                foreach (var e in eventModel.Visitors)
                {
                    visitors.Add(e.Id);
                }
            }

            backendEventModel.Owner    = owner.Id;
            backendEventModel.Visitors = visitors.ToArray();

            return(backendEventModel);
        }