public async Task <ActionResult <DeliveryItem> > PostDeliveryItem(DeliveryItem delivery)
{
if (delivery == null)
{
throw new System.ArgumentNullException(nameof(delivery));
}
else if (delivery.OrderItems == null)
{
throw new System.ArgumentNullException(nameof(delivery.OrderItems));
}
// Retrieving all orders from delivery
ICollection <OrderItem> orders = await CommonOperations.ExtractOrders(delivery, _context);
delivery.OrderItems = orders;
delivery.Status = "created";
_context.DeliveryItems.Add(delivery);
await _context.SaveChangesAsync();
return(CreatedAtAction(nameof(GetDeliveryItem), new { id = delivery.DeliveryId }, delivery));
}