public async Task <Item> CreateItemAsync(string itemName, string url, string[] emails)
        {
            var itemToCreate = new ItemPOCO
            {
                Id   = Guid.NewGuid().ToString(),
                Name = itemName,
                Url  = url,
                SubscribersEmails = emails
            };

            context.Items.Add(itemToCreate);

            await context.SaveChangesAsync();

            return(itemToCreate.ToItem());
        }
        public async Task <Item> AddSubscriberToItemAsync(Item item, string email)
        {
            ItemPOCO itemInDb = context.Items.First(i => i.Id == item.Id);

            if (itemInDb.SubscribersEmails.Contains(email))
            {
                return(itemInDb.ToItem());
            }

            itemInDb.SubscribersEmails = itemInDb.SubscribersEmails.Append(email).ToArray();

            context.Items.Update(itemInDb);

            await context.SaveChangesAsync();

            return(itemInDb.ToItem());
        }