public IActionResult GetOpenOrderByUserId(Order userId)
        {
            // 1. validate user exists
            var validUser = _usersRepository.GetUserById(userId.UserId);

            if (validUser != null)
            {
                // 2. go to repo and check to see if there are any open orders for the user
                // TODO: this should be only open orders below...
                var order = _ordersRepository.GetOpenUserOrder(userId.UserId);
                //var isEmpty = !order.Any();
                // 3a. if not, create a new order and return the id on the new order
                if (order == null)
                {
                    _ordersRepository.AddNewOrder(userId);
                    var newOrder = _ordersRepository.GetOpenUserOrder(userId.UserId);
                    return(Created("", newOrder));
                }
                // 3a. if yes, return the order id
                return(Ok(order));
            }
            return(NotFound("This user does not exist."));
        }