private TableOperation PrepareDeleteOperationFor(string userId)
        {
            var userToDelete = new StoredUser {
                UserName = userId
            };

            return(TableOperation.Delete(userToDelete));
        }
        private TableOperation PrepareStoreOperationFor(IUser <string> user)
        {
            var userToStore = new StoredUser(user);

            return(TableOperation.InsertOrMerge(userToStore));
        }