public async Task <IActionResult> GetAsync(Guid id)
{
var deck = await decksService.GetAsync(id);
var cards = await Task.WhenAll(deck.CardsIds
.Select(cardId => cardsService.GetAsync(cardId)));
return(Ok(new DeckModel
{
Id = deck.Id,
Name = deck.Name,
Cards = cards
.ToList()
}));
}