亿级高并发电商项目-- 实战篇 --万达商城项目 十三（编写购物车、优化修改商品、下架商品方法、购物车模块监听修改商品、删除商品消息）

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 专栏:高并发项目 

编写购物车服务接口

用户购买商品的流程为： 搜索商品 > 查看商品详情 > 添加到购物车 > 生成商品订单 > 支 付 ，搜索商品和查看商品详情功能已经完成，接下来我们编写购物 车服务。购物车数据属于临时数据，为了节约数据库开销，我们会 将其存放到redis中。

在通用模块编写购物车服务接口：

// 购物车服务
public interface CartService {// 新增商品到购物车void addCart(Long userId, CartGoods cartGoods);// 修改购物车商品数量void handleCart(Long userId, Long goodId, Integer num);// 删除购物车商品void deleteCartOption(Long userId, Long goodId);// 获取用户购物车List<CartGoods> findCartList(Long userId);// 更新redis中的商品数据，在管理员更新商品后执行void refreshCartGoods(CartGoods cartGoods);// 删除redis中的商品数据，在管理员下架商品后执行void deleteCartGoods(CartGoods cartGoods);
}

创建购物车服务模块

1、创建名为 shopping_cart_service 的SpringBoot工程，添加相关依赖。

<dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter</artifactId></dependency><dependency><groupId>com.itbaizhan</groupId><artifactId>shopping_common</artifactId><version>0.0.1-SNAPSHOT</version></dependency><!-- dubbo --><dependency><groupId>org.apache.dubbo</groupId><artifactId>dubbo-spring-boot-starter</artifactId><version>2.7.8</version></dependency><!-- 操作zookeeper --><dependency><groupId>org.apache.curator</groupId><artifactId>curator-recipes</artifactId><version>4.2.0</version></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><!-- redis --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-redis</artifactId></dependency>
</dependencies>

 2、设置该工程的父工程为 shopping 。

<parent><groupId>com.ittxc</groupId><artifactId>shopping</artifactId><version>1.0-SNAPSHOT</version>
</parent>

3、给 shopping 工程设置子模块

<!-- 子模块 -->
<modules><!-- 购物车服务 --><module>shopping_cart_service</module>
</modules>

4、编写配置文件 application.yml

# 端口号
server:port: 9009
# 日志格式
logging:pattern:console: '%d{HH:mm:ss.SSS} %clr(%-5level) --- [%-15thread] %cyan(%-50logger{50}):%msg%n'
spring:# redisredis:host: 192.168.0.159port: 6379timeout: 30000jedis:pool:max-active: 8max-wait: -1max-idle: 8min-idle: 0
dubbo:application:name: shopping_cart_service # 项目名registry:address: zookeeper://192.168.0.159 #注册中心地址port: 2181       # 注册中心的端口timeout: 10000 # 注册到zk上超时时间，msprotocol:name: dubbo # dubbo使用的协议port: -1 # dubbo自动分配端口scan:base-packages: com.itbaizhan.shopping_cart_service.service # 包扫描

5、启动类忽略数据源自动配置

@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})
public class ShoppingCartServiceApplication {public static void main(String[] args)
{SpringApplication.run(ShoppingCartServiceApplication.class, args);}
}

创建购物车Api模块

1、创建名为 shopping_cart_customer_api 的SpringBoot工程，添加相关依赖。

<dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!-- dubbo --><dependency><groupId>org.apache.dubbo</groupId><artifactId>dubbo-spring-boot-starter</artifactId><version>2.7.8</version></dependency><!-- 操作zookeeper --><dependency><groupId>org.apache.curator</groupId><artifactId>curator-recipes</artifactId><version>4.2.0</version></dependency><dependency><groupId>com.itbaizhan</groupId><artifactId>shopping_common</artifactId><version>0.0.1-SNAPSHOT</version></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-startertest</artifactId><scope>test</scope></dependency>
</dependencies>

 2、设置该工程的父工程为 shopping 。

<parent><groupId>com.ittxc</groupId><artifactId>shopping</artifactId><version>1.0-SNAPSHOT</version>
</parent>

3、给 shopping 工程设置子模块

<!-- 子模块 -->
<modules><!-- 购物车api --><module>shopping_cart_customer_api</module>
</modules>

4、编写配置文件 application.yml

# 端口号
server:port: 8005
# 日志格式
logging:pattern:console: '%d{HH:mm:ss.SSS} %clr(%-5level) --- [%-15thread] %cyan(%-50logger{50}):%msg%n'
dubbo:application:name: shopping_cart_customer_api # 项目名registry:address: zookeeper://192.168.0.159 #注册中心地址port: 2181       # 注册中心的端口timeout: 10000 # 注册到zk上超时时间，msprotocol:name: dubbo # dubbo使用的协议port: -1 # dubbo自动分配端口

5、启动类忽略数据源自动配置

@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})
public class ShoppingUserCustomerApiApplication {public static void main(String[] args)
{SpringApplication.run(ShoppingUserCustomerApiApplication.class, args);}
}

编写查询用户购物车功能

我们将用户的购物车信息保存到redis当中，所有用户的购物车作为 一个hash类型的数据保存，hash的键是用户id，hash的值是购物车商品列表。

 在购物车服务模块创建购物车服务接口的实现类，重写查询用户购物车功能

@DubboService
public class CartServiceImpl implements CartService {@Autowiredprivate RedisTemplate redisTemplate;@Overridepublic List<CartGoods> findCartList(Long userId) {Object cartList = redisTemplate.boundHashOps("cartList").get(userId);if (cartList == null) {return new ArrayList<CartGoods>();} else {return (List<CartGoods>)cartList;}}
}

 编写添加商品到购物车方法

@Override
public void addCart(Long userId, CartGoods cartGoods) {// 1.根据用户id获取用户购物车列表List<CartGoods> cartList = findCartList(userId);// 2.查询购物车是否有该商品，如果有商品，添加商品数量for (CartGoods cartGoods1 : cartList) {if(cartGoods.getGoodId().equals(cartGoods1.getGoodId())){int newNum = cartGoods1.getNum() + cartGoods.getNum();cartGoods1.setNum(newNum);redisTemplate.boundHashOps("cartList").put(userId,cartList);return;}}// 3.如果购物车没有该商品，将商品添加到购物车列表cartList.add(cartGoods);redisTemplate.boundHashOps("cartList").put(userId,cartList);
}

编写修改购物车商品数量方法

@Override
public void handleCart(Long userId, Long goodId, Integer num) {// 获取用户购物车列表List<CartGoods> cartList = findCartList(userId);// 遍历列表找到对应商品for (CartGoods cartGoods : cartList) {if(goodId.equals(cartGoods.getGoodId())) {// 改变商品数量cartGoods.setNum(num);break;}}// 将新的购物车列表保存到redis中redisTemplate.boundHashOps("cartList").put(userId, cartList);
}

编写删除购物车商品方法

@Override
public void deleteCartOption(Long userId,Long goodId) {// 获取用户购物车列表List<CartGoods> cartList = findCartList(userId);// 将商品移出列表for (CartGoods cartGoods : cartList) {if (goodId.equals(cartGoods.getGoodId())) {cartList.remove(cartGoods);break;}}// 将新的购物车列表保存到redis中redisTemplate.boundHashOps("cartList").put(userId, cartList);
}

编写购物车控制器

在进行购物车操作之前，要先获取用户的Id，而用户的令牌中只保存了用户名，所以我们要修改JWT工具类，让令牌中也保存用户的 Id：

1、修改JWT工具类

public class JWTUtil {//token过期时间，一天private static final Long EXPIRE_DATE = 1000*60*60*24L;// 秘钥private static final String SECRET = "xiaotong";// 签发者private static final String ISSUER = "XIAOTONG";/*** 签名生成* @param shoppingUser* @return*/public static String sign(ShoppingUser shoppingUser){String token = JWT.create().withIssuer(ISSUER) // 签发者.withIssuedAt(new Date())// 签发时间.withExpiresAt(new Date(new Date().getTime() + EXPIRE_DATE))// 过期时间.withSubject(shoppingUser.getUsername())// 保存用户名.withClaim("userId",shoppingUser.getId())// 保存用户id.sign(Algorithm.HMAC256(SECRET)); // 秘钥return token;}/*** 签名解析* @param token 签名字符串* @return 解析得出的用户名*/public static String verify(String token){try {String username = JWT.require(Algorithm.HMAC256(SECRET)).withIssuer(ISSUER).build().verify(token).getSubject();return username;} catch (Exception e){throw new BusException(CodeEnum.VERIFY_TOKEN_ERROR);}}/*** 签名解析，获取用户id* @param token 签名字符串* @return 用户id*/public static Long getId(String token){try {Long userId = JWT.require(Algorithm.HMAC256(SECRET)).withIssuer(ISSUER).build().verify(token).getClaim("userId").asLong();return userId;} catch (Exception e){throw new BusException(CodeEnum.VERIFY_TOKEN_ERROR);}}
}

2、在购物车Api模块编写购物车控制器

/**
* 购物车
*/
@RestController
@RequestMapping("/user/cart")
public class CartController {@DubboReferenceprivate CartService cartService;/*** 查询用户购物车* @param token 用户令牌* @return 用户购物车列表*/@GetMapping("/findCartList")public BaseResult<List<CartGoods>> findCartList(@RequestHeader String token){Long userId = JWTUtil.getId(token); // 获取用户idList<CartGoods> cartList = cartService.findCartList(userId);return BaseResult.ok(cartList);}/*** 新增商品到购物车* @param cartGoods 购物车商品* @param token 用户令牌* @return 操作结果*/@PostMapping("/addCart")public BaseResult addCart(@RequestBody CartGoods cartGoods,@RequestHeader String token){Long userId = JWTUtil.getId(token); // 获取用户idcartService.addCart(userId,cartGoods);return BaseResult.ok();}/*** 修改购物车商品数量* @param token 用户令牌* @param goodId 商品id* @param num 修改后的数量* @return 操作结果*/@GetMapping("/handleCart")public BaseResult addCart(@RequestHeader String token,Long goodId,Integer num){Long userId = JWTUtil.getId(token); // 获取用户idcartService.handleCart(userId,goodId,num);return BaseResult.ok();}/*** 删除购物车商品* @param token 用户令牌* @param goodId 商品id* @return 操作结果*/@DeleteMapping("/deleteCart")public BaseResult addCart(@RequestHeader String token,Long goodId){Long userId = JWTUtil.getId(token); // 获取用户idcartService.deleteCartOption(userId,goodId);return BaseResult.ok();}
}

编写修改所有用户购物车商品方法

当管理员修改了商品的价格等数据后，需要将数据同步到用户购物车中，所以我们要编写给所有用户的购物车中修改某件商品的方法。

@Override
public void refreshCartGoods(CartGoods
cartGoods) {// 获取所有用户购物车商品BoundHashOperations cartList = redisTemplate.boundHashOps("cartList");Map<Long,List<CartGoods>> allCartGoods = cartList.entries();Set<Map.Entry<Long, List<CartGoods>>> entries = allCartGoods.entrySet();// 遍历所有用户的购物车for (Map.Entry<Long, List<CartGoods>> entry : entries) {List<CartGoods> goodsList = entry.getValue();// 遍历一个用户购物车的所有商品for (CartGoods goods : goodsList) {// 如果该商品是被更新的商品，修改商品数据if(cartGoods.getGoodId().equals(goods.getGoodId())){goods.setGoodsName(cartGoods.getGoodsName());goods.setHeaderPic(cartGoods.getHeaderPic());goods.setPrice(cartGoods.getPrice());}}}// 将改变后所有用户购物车重新放入redisredisTemplate.delete("cartList");redisTemplate.boundHashOps("cartList").putAll(allCartGoods);
}

编写删除所有用户购物车商品方法

当管理员下架某件商品后，所有用户的购物车中该商品也应该被删除，所以我们要编写给所有用户的购物车中删除某件商品的方法。

@Override
public void deleteCartGoods(CartGoods cartGoods) {BoundHashOperations cartList = redisTemplate.boundHashOps("cartList");// 所有用户的购物车Map<String,List<CartGoods>> allCartGoods = cartList.entries();Set<Map.Entry<String, List<CartGoods>>> entries = allCartGoods.entrySet();// 遍历所有用户的购物车for (Map.Entry<String, List<CartGoods>> entry : entries) {List<CartGoods> goodsList = entry.getValue();// 遍历一个用户购物车的所有商品for (CartGoods goods : goodsList) {// 如果该商品是被删除的商品if (cartGoods.getGoodId().equals(goods.getGoodId())){goodsList.remove(goods);break;}}}// 将改变后的map重新放入redisredisTemplate.delete("cartList");redisTemplate.boundHashOps("cartList").putAll(allCartGoods);
}

 优化修改商品、下架商品方法

接下来我们修改商品服务模块代码，在修改商品后发送消息同步修 改购物车数据；在下架商品后发送消息同步删除购物车数据：

1、在MQ配置文件创建队列，绑定队列到交换机：

@Configuration
public class RabbitConfig {// 交换机private final String GOODS_EXCHANGE = "goods_exchange";// 同步商品数据队列private final String SYNC_GOODS_QUEUE = "sync_goods_queue";// 删除商品数据队列private final String DEL_GOODS_QUEUE = "del_goods_queue";// 向购物车同步商品队列private final String SYNC_CART_QUEUE = "sync_cart_queue";// 向购物车删除商品队列private final String DEL_CART_QUEUE = "del_cart_queue";// 创建交换机@Bean(GOODS_EXCHANGE)public Exchange getExchange() {return ExchangeBuilder.topicExchange(GOODS_EXCHANGE) // 交换机类型.durable(true) // 是否持久化.build();}// 创建队列@Bean(SYNC_GOODS_QUEUE)public Queue getQueue1() {return new Queue(SYNC_GOODS_QUEUE); // 队列名}@Bean(DEL_GOODS_QUEUE)public Queue getQueue2() {return new Queue(DEL_GOODS_QUEUE);// 队列名}@Bean(SYNC_CART_QUEUE)public Queue getQueue3() {return new Queue(SYNC_CART_QUEUE);// 队列名}@Bean(DEL_CART_QUEUE)public Queue getQueue4() {return new Queue(DEL_CART_QUEUE);
// 队列名}// 交换机绑定队列@Beanpublic Binding bindQueue1(@Qualifier(GOODS_EXCHANGE) Exchange exchange,@Qualifier(SYNC_GOODS_QUEUE) Queue queue){return BindingBuilder.bind(queue).to(exchange).with("#.sync_goods.#").noargs();}@Beanpublic Binding bindQueue2(@Qualifier(GOODS_EXCHANGE) Exchange exchange,@Qualifier(DEL_GOODS_QUEUE) Queue queue) {return BindingBuilder.bind(queue).to(exchange).with("#.del_goods.#").noargs();}@Beanpublic Binding
bindQueue3(@Qualifier(GOODS_EXCHANGE)
Exchange exchange,@Qualifier(SYNC_CART_QUEUE) Queue queue)
{return BindingBuilder.bind(queue).to(exchange).with("#.sync_cart.#").noargs();}@Beanpublic Binding bindQueue4(@Qualifier(GOODS_EXCHANGE) Exchange exchange,@Qualifier(DEL_CART_QUEUE) Queue queue) {return BindingBuilder.bind(queue).to(exchange).with("#.del_cart.#").noargs();}
}

@DubboService
public class GoodsServiceImpl implements
GoodsService {@Autowiredprivate GoodsMapper goodsMapper;@Autowiredprivate GoodsImageMapper goodsImageMapper;@Autowiredprivate RabbitTemplate rabbitTemplate;@Overridepublic void update(Goods goods) {// 删除旧图片数据Long goodsId = goods.getId(); //商品idQueryWrapper<GoodsImage> queryWrapper = new QueryWrapper();queryWrapper.eq("goodsId",goodsId);goodsImageMapper.delete(queryWrapper);// 删除旧规格项数据goodsMapper.deleteGoodsSpecificationOption(goodsId);// 插入商品数据goodsMapper.updateById(goods);// 插入图片数据List<GoodsImage> images = goods.getImages(); // 商品图片for (GoodsImage image : images) {image.setGoodsId(goodsId); // 给图片设置商品idgoodsImageMapper.insert(image); // 插入图片}// 插入商品_规格项数据List<Specification> specifications = goods.getSpecifications(); // 获取规格List<SpecificationOption> options = new ArrayList(); // 规格项集合// 遍历规格，获取规格中的所有规格项for (Specification specification : specifications) {options.addAll(specification.getSpecificationOptions());}// 遍历规格项，插入商品_规格项数据for (SpecificationOption option : options) {goodsMapper.addGoodsSpecificationOption(goodsId,option.getId());}rabbitTemplate.convertAndSend("goods_exchange","sync_goods",findById(goodsId));// 将商品修改数据同步到用户购物车CartGoods cartGoods = new CartGoods();cartGoods.setGoodId(goods.getId());cartGoods.setGoodsName(goods.getGoodsName());cartGoods.setHeaderPic(goods.getHeaderPic());cartGoods.setPrice(goods.getPrice());rabbitTemplate.convertAndSend("goods_exchange","sync_cart",cartGoods);}@Overridepublic void putAway(Long id, Boolean isMarketable) {goodsMapper.putAway(id,isMarketable);if (isMarketable){// 上架时同步到ESrabbitTemplate.convertAndSend("goods_exchange","sync_goods",findById(id));}else{// 下架删除ES数据rabbitTemplate.convertAndSend("goods_exchange","del_goods",id);// 商品下架删除用户购物车CartGoods cartGoods = new CartGoods();cartGoods.setGoodId(id);rabbitTemplate.convertAndSend("goods_exchange","del_cart",cartGoods);}}
}

购物车模块监听修改商品、删除商品消息

1、在购物车服务模块添加RabbitMQ依赖

<!-- RabbitMQ -->
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-amqp</artifactId>
</dependency>

2、添加RabbitMQ配置

spring:# redisredis:host: 192.168.0.159port: 6379timeout: 30000jedis:pool:max-active: 8max-wait: -1max-idle: 8min-idle: 0# rabbitmqrabbitmq:host: 192.168.0.159port: 5672username: guestpassword: guestvirtual-host: /

3、修改购物车服务接口实现类，监听队列 

@DubboService
@Service
public class CartServiceImpl implements CartService {@Autowiredprivate RedisTemplate redisTemplate;// 监听修改购物车商品队列@RabbitListener(queues = "sync_cart_queue")public void listenSyncQueue(CartGoods cartGoods){refreshCartGoods(cartGoods);}// 监听删除购物车商品队列@RabbitListener(queues = "del_cart_queue")public void listenDelQueue(CartGoods cartGoods){deleteCartGoods(cartGoods);}
}

4、测试管理员修改商品、下架商品，看用户购物车是否发生改变。