如何利用Go语言开发点餐系统的订单管理功能

CREATE TABLE `orders` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `user_id` int(11) NOT NULL,
  `status` tinyint(4) NOT NULL DEFAULT '0' COMMENT '0：待处理，1：正在配送，2：已完成',
  `create_time` datetime NOT NULL,
  `total_price` int(11) NOT NULL,
  `delivery_address` varchar(255) DEFAULT '',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

CREATE TABLE `order_items` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `order_id` int(11) NOT NULL,
  `product_id` int(11) NOT NULL,
  `product_name` varchar(255) NOT NULL,
  `product_price` int(11) NOT NULL,
  `product_count` int(11) NOT NULL,
  `create_time` datetime NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

func AddOrder(w Http.ResponseWriter, r *http.Request) {
    // 解析请求参数
    r.ParseFORM()
    userId, _ := strconv.Atoi(r.Form.Get("user_id"))
    products := r.Form.Get("products")
    deliveryAddress := r.Form.Get("delivery_address")
    
    // 计算订单总价
    totalPrice := 0
    productIds := strings.Split(products, ",")
    for _, productId := range productIds {
        product, _ := GetProductById(productId)
        totalPrice += product.Price
    }
    
    // 添加订单到数据库
    now := time.Now().Format("2006-01-02 15:04:05")
    orderId, _ := AddOrderToDB(userId, totalPrice, deliveryAddress, now)
    
    // 添加订单详情到数据库
    for _, productId := range productIds {
        product, _ := GetProductById(productId)
        orderItem := OrderItem{
            OrderId:    orderId,
            ProductId:  productId,
            ProductName:product.Name,
            ProductPrice:product.Price,
            ProductCount:1,
            CreateTime:now,
        }
        AddOrderItemToDB(orderItem)
    }
    
    // 返回成功信息
    resp := Resp{Code: 200, Msg: "add order success"}
    WriteJSON(w, resp)
}

func GetOrderList(w http.ResponseWriter, r *http.Request) {
    // 查询数据库获取订单列表
    orders, _ := GetOrderListFromDB()

    // 构造响应数据
    resp := Resp{Code: 200, Data: orders}

    // 返回订单列表数据
    WritejsON(w, resp)
}

func UpdateOrder(w http.ResponseWriter, r *http.Request) {
    // 解析请求参数
    r.ParseForm()
    orderId, _ := strconv.Atoi(r.Form.Get("order_id"))
    deliveryAddress := r.Form.Get("delivery_address")

    // 更新订单信息到数据库中
    UpdateOrderToDB(orderId, deliveryAddress)

    // 返回成功信息
    resp := Resp{Code: 200, Msg: "update order success"}
    WriteJSON(w, resp)
}

func DeleteOrder(w http.ResponseWriter, r *http.Request) {
    // 解析请求参数
    r.ParseForm()
    orderId, _ := strconv.Atoi(r.Form.Get("order_id"))

    // 从数据库中删除订单信息
    DeleteOrderFromDB(orderId)

    // 返回成功信息
    resp := Resp{Code: 200, Msg: "delete order success"}
    WriteJSON(w, resp)
}

func UpdateOrderStatus(w http.ResponseWriter, r *http.Request) {
    // 解析请求参数
    r.ParseForm()
    orderId, _ := strconv.Atoi(r.Form.Get("order_id"))
    status, _ := strconv.Atoi(r.Form.Get("status"))

    // 更新订单状态到数据库中
    UpdateOrderStatusToDB(orderId, status)

    // 返回成功信息
    resp := Resp{Code: 200, Msg: "update order status success"}
    WriteJSON(w, resp)
}