//Scenario

//You work for an e-commerce company that has an order processing API built in .NET. Recently, users have reported slow response times when they place orders, 

//especially during peak hours. The client has requested that the API’s response time be reduced to under 200ms, as any delay directly impacts user experience and sales.

​

​

public async Task<IActionResult> ProcessOrder(OrderRequest request)

{

    // Step 1: Retrieve product details from the microservice

    var product = await _productService.GetProductDetailsAsync(request.ProductId);

    if (product == null)

        return BadRequest("Product not found.");

​

    // Step 2: Check stock availability

    if (product.Stock < request.Quantity)

        return BadRequest("Insufficient stock.");

​

    // Step 3: Calculate total price

    var totalPrice = product.Price * request.Quantity;

    if (request.ApplyDiscount && product.IsDiscountEligible)

    {

        totalPrice *= 0.9; // Apply a 10% discount

    }

​

    // Step 4: Save order to database

    var order = new Order

    {

        ProductId = product.Id,

        Quantity = request.Quantity,

        TotalPrice = totalPrice,

        OrderDate = DateTime.UtcNow

    };

    _dbContext.Orders.Add(order);

    await _dbContext.SaveChangesAsync();

​

    // Step 5: Send confirmation email

    await _emailService.SendOrderConfirmationAsync(request.UserEmail, order);

​

    return Ok("Order processed successfully.");

}

​