public async Task SepeteUrunEkle(int musteriId, int urunId, int adet)
        {
            var entity = await GetirMusteriSepetiEntity(musteriId);

            var sepet = MusteriSepetiEntityToMusteriSepetiOrDefault(musteriId, entity);

            sepet.UrunEkle(urunId, adet);

            if (entity == null)
            {
                entity = new MusteriSepetiEntity()
                {
                    MusteriId = musteriId,
                    Items     = sepet.Items
                };
                await _context.MusteriSepeti.InsertOneAsync(entity);
            }
            else
            {
                entity.Items = sepet.Items;

                await _context.MusteriSepeti.ReplaceOneAsync(
                    x => x.MusteriId == musteriId,
                    entity
                    );
            }
        }
        private MusteriSepeti MusteriSepetiEntityToMusteriSepetiOrDefault(int musteriId, MusteriSepetiEntity entity)
        {
            var sepet = new MusteriSepeti(musteriId);

            if (entity != null)
            {
                sepet.Items = entity.Items;
            }

            return(sepet);
        }