商城项目十二、购物车模块开发

1.功能介绍

加入商品
更新商品数
查询商品数
移除商品
单选/取消
全选/取消
购物车列表
...

2.学习目标

购物车模块的设计思想
如何封装一个高复用购物车核心方法
解决浮点型商业运算中丢失精度的问题
...

3.数据库设计

CREATE TABLE `mmall_cart` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `user_id` int(11) NOT NULL,
  `product_id` int(11) DEFAULT NULL COMMENT '商品id',
  `quantity` int(11) DEFAULT NULL COMMENT '数量',
  `checked` int(11) DEFAULT NULL COMMENT '是否选择,1=已勾选,0=未勾选',
  `create_time` datetime DEFAULT NULL COMMENT '创建时间',
  `update_time` datetime DEFAULT NULL COMMENT '更新时间',
  PRIMARY KEY (`id`),
  KEY `user_id_index` (`user_id`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=146 DEFAULT CHARSET=utf8;

4.接口设计

[MENU]

1.购物车List列表

/cart/list.do
http://localhost:8080/cart/list.do
注意点：
需要先登录,所有的密码都是123
NEED_LOGIN(10, "NEED_LOGIN"),//需要登录的错误编码
价格的单位是元,保留小数后2位

request

无参数,需要登录状态

response

success
{
    "status": 0,
    "data": {
        "cartProductVoList": [
            {
                "id": 1,
                "userId": 13,
                "productId": 1,
                "quantity": 1,
                "productName": "iphone7",
                "productSubtitle": "双十一促销",
                "productMainImage": "mainimage.jpg",
                "productPrice": 7199.22,
                "productStatus": 1,
                "productTotalPrice": 7199.22,
                "productStock": 86,
                "productChecked": 1,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            },
            {
                "id": 2,
                "userId": 13,
                "productId": 2,
                "quantity": 1,
                "productName": "oppo R8",
                "productSubtitle": "oppo促销进行中",
                "productMainImage": "mainimage.jpg",
                "productPrice": 2999.11,
                "productStatus": 1,
                "productTotalPrice": 2999.11,
                "productStock": 86,
                "productChecked": 1,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            }
        ],
        "allChecked": true,
        "cartTotalPrice": 10198.33
    }
}

fail

{
    "status": 10,
    "msg": "用户未登录,请登录"
}

2.购物车添加商品

/cart/add.do
http://localhost:8080/cart/add.do?productId=1&count=10
请注意这个字段，超过数量会返回这样的标识"limitQuantity"
失败的：LIMIT_NUM_FAIL 成功的：LIMIT_NUM_SUCCESS

request

productId,count

response

success

{
    "status": 0,
    "data": {
        "cartProductVoList": [
            {
                "id": 1,
                "userId": 13,
                "productId": 1,
                "quantity": 12,
                "productName": "iphone7",
                "productSubtitle": "双十一促销",
                "productMainImage": "mainimage.jpg",
                "productPrice": 7199.22,
                "productStatus": 1,
                "productTotalPrice": 86390.64,
                "productStock": 86,
                "productChecked": 1,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            },
            {
                "id": 2,
                "userId": 13,
                "productId": 2,
                "quantity": 1,
                "productName": "oppo R8",
                "productSubtitle": "oppo促销进行中",
                "productMainImage": "mainimage.jpg",
                "productPrice": 2999.11,
                "productStatus": 1,
                "productTotalPrice": 2999.11,
                "productStock": 86,
                "productChecked": 1,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            }
        ],
        "allChecked": true,
        "cartTotalPrice": 89389.75
    }
}

fail

{
    "status": 10,
    "msg": "用户未登录,请登录"
}

3.更新购物车某个产品数量

/cart/update.do
http://localhost:8080/cart/update.do?productId=1&count=2

request

productId,count

response

响应同2
success

{
    "status": 0,
    "data": {
        "cartProductVoList": [
            {
                "id": 1,
                "userId": 13,
                "productId": 1,
                "quantity": 12,
                "productName": "iphone7",
                "productSubtitle": "双十一促销",
                "productMainImage": "mainimage.jpg",
                "productPrice": 7199.22,
                "productStatus": 1,
                "productTotalPrice": 86390.64,
                "productStock": 86,
                "productChecked": 1,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            },
            {
                "id": 2,
                "userId": 13,
                "productId": 2,
                "quantity": 1,
                "productName": "oppo R8",
                "productSubtitle": "oppo促销进行中",
                "productMainImage": "mainimage.jpg",
                "productPrice": 2999.11,
                "productStatus": 1,
                "productTotalPrice": 2999.11,
                "productStock": 86,
                "productChecked": 1,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            }
        ],
        "allChecked": true,
        "cartTotalPrice": 89389.75
    }
}

fail

{
    "status": 10,
    "msg": "用户未登录,请登录"
}

4.移除购物车某个产品

/cart/delete_product.do
http://localhost:8080/cart/delete_product.do?productIds=1,3

request

productIds

response

success

{
    "status": 0,
    "data": {
        "cartProductVoList": [
            {
                "id": 2,
                "userId": 13,
                "productId": 2,
                "quantity": 1,
                "productName": "oppo R8",
                "productSubtitle": "oppo促销进行中",
                "productMainImage": "mainimage.jpg",
                "productPrice": 2999.11,
                "productStatus": 1,
                "productTotalPrice": 2999.11,
                "productStock": 86,
                "productChecked": 1,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            }
        ],
        "allChecked": true,
        "cartTotalPrice": 2999.11
    }
}

fail

{
    "status": 10,
    "msg": "用户未登录,请登录"
}

5.购物车选中某个商品

/cart/select.do
http://localhost:8080/cart/select.do?productId=1

request

productId

response

success

{
    "status": 0,
    "data": {
        "cartProductVoList": [
            {
                "id": 2,
                "userId": 13,
                "productId": 2,
                "quantity": 1,
                "productName": "oppo R8",
                "productSubtitle": "oppo促销进行中",
                "productMainImage": "mainimage.jpg",
                "productPrice": 2999.11,
                "productStatus": 1,
                "productTotalPrice": 2999.11,
                "productStock": 86,
                "productChecked": 1,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            }
        ],
        "allChecked": true,
        "cartTotalPrice": 2999.11
    }
}

fail

{
    "status": 10,
    "msg": "用户未登录,请登录"
}

6.购物车取消选中某个商品

/cart/un_select.do
http://localhost:8080/cart/un_select.do?productId=2
注意返回值中的cartTotalPrice，如果反选之后总价的变化

request

productId

response

success

{
    "status": 0,
    "data": {
        "cartProductVoList": [
            {
                "id": 2,
                "userId": 13,
                "productId": 2,
                "quantity": 1,
                "productName": "oppo R8",
                "productSubtitle": "oppo促销进行中",
                "productMainImage": "mainimage.jpg",
                "productPrice": 2999.11,
                "productStatus": 1,
                "productTotalPrice": 2999.11,
                "productStock": 86,
                "productChecked": 0,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            }
        ],
        "allChecked": true,
        "cartTotalPrice": 0
    }
}

fail

{
    "status": 10,
    "msg": "用户未登录,请登录"
}

7.查询在购物车里的产品数量

/cart/get_cart_product_count.do
http://localhost:8080/cart/get_cart_product_count.do
未登录返回0

request

无

response

success

{
    "status": 0,
    "data": 0
}

fail

{
    "status": 10,
    "msg": "出现异常"
}

8.购物车全选

/cart/select_all.do
http://localhost:8080/cart/select_all.do
注意返回值中的cartTotalPrice的变化

request

无

response

success

{
    "status": 0,
    "data": {
        "cartProductVoList": [
            {
                "id": 2,
                "userId": 13,
                "productId": 2,
                "quantity": 1,
                "productName": "oppo R8",
                "productSubtitle": "oppo促销进行中",
                "productMainImage": "mainimage.jpg",
                "productPrice": 2999.11,
                "productStatus": 1,
                "productTotalPrice": 2999.11,
                "productStock": 86,
                "productChecked": 0,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            }
        ],
        "allChecked": true,
        "cartTotalPrice": 2999.11
    }
}

fail

{
    "status": 10,
    "msg": "用户未登录,请登录"
}

9.购物车取消全选

/cart/un_select_all.do
http://localhost:8080/cart/un_select_all.do
注意返回值中的cartTotalPrice总价的变化

request

无

response

success

{
    "status": 0,
    "data": {
        "cartProductVoList": [
            {
                "id": 2,
                "userId": 13,
                "productId": 2,
                "quantity": 1,
                "productName": "oppo R8",
                "productSubtitle": "oppo促销进行中",
                "productMainImage": "mainimage.jpg",
                "productPrice": 2999.11,
                "productStatus": 1,
                "productTotalPrice": 2999.11,
                "productStock": 86,
                "productChecked": 0,
                "limitQuantity": "LIMIT_NUM_SUCCESS"
            }
        ],
        "allChecked": true,
        "cartTotalPrice": 0
    }
}

fail

{
    "status": 10,
    "msg": "用户未登录,请登录"
}