public ProductService()
{
Db = new StorageDatabaseContextFactory().Create();
}
public void Reserve(ReserveReq req)
{
if (req.IsNull())
{
throw new ArgumentNullException(nameof(req));
}
if (req.ProductId.IsEmpty())
{
throw new ArgumentException(nameof(req.ProductId));
}
if (req.Quantity <= 0)
{
throw new ArgumentException(nameof(req.Quantity));
}
try
{
TransactionOptions transOpt = new TransactionOptions
{
IsolationLevel = IsolationLevel.Serializable
};
using (TransactionScope scope = new TransactionScope(TransactionScopeOption.RequiresNew, transOpt))
{
using (var context = new StorageDatabaseContextFactory().Create())
{
string sqlQuery = $"SELECT * FROM [ExpressShop.Storage].[dbo].[EntProducts] WITH (UPDLOCK) WHERE Id = '{req.ProductId}'";
var product = context.Products
.SqlQuery(sqlQuery)
.FirstOrDefault();
Logger.Write($"{Thread.CurrentThread.Name}. Получение товара из бд. Текущий остаток: {product.TotalQuantity}");
Logger.Write($"{Thread.CurrentThread.Name}. Запрос товара. Количество: {req.Quantity}");
if (product.TotalQuantity == 0)
{
Logger.Write($"{Thread.CurrentThread.Name}. Товар закончился");
scope.Complete();
return;
}
else if (product.TotalQuantity - req.Quantity < 0)
{
Logger.Write($"{Thread.CurrentThread.Name}. Количество товара, запрошенное для бронирования, больше чем есть на складе");
scope.Complete();
return;
}
else
{
product.TotalQuantity -= req.Quantity;
var reservation = new EntReservation
{
Id = Guid.NewGuid(),
Characteristics = product.Characteristics,
ProductId = product.Id,
Quantity = req.Quantity,
OwnerId = Guid.NewGuid()
};
context.Reservations.Add(reservation);
context.SaveChanges();
Logger.Write($"{Thread.CurrentThread.Name}. Создание бронирования");
Logger.Write($"{Thread.CurrentThread.Name}. Сохранение товара. Остаток: {product.TotalQuantity}");
}
}
scope.Complete();
}
}
catch (Exception ex)
{
Logger.Write($"{Thread.CurrentThread.Name}. Произошла ошибка при бронировании товара: {ex.Message}");
}
}
