完成基本下单的学习

stock-service/src/main/java/cn/mayiming/App.java

@@ -1,13 +1,21 @@
 package cn.mayiming;
 
+import org.mybatis.spring.annotation.MapperScan;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.transaction.annotation.EnableTransactionManagement;
+
 /**
  * Hello world!
  *
  */
+@SpringBootApplication
+@EnableTransactionManagement
+@MapperScan("cn.mayiming.Mapper")
 public class App 
 {
     public static void main( String[] args )
     {
-        System.out.println( "Hello World!" );
+        SpringApplication.run(App.class, args);
     }
 }

stock-service/src/main/java/cn/mayiming/Controller/stockController.java

@@ -0,0 +1,23 @@
+package cn.mayiming.Controller;
+
+
+import cn.mayiming.Entity.StockDeductDTO;
+import cn.mayiming.Service.stockService;
+import jakarta.validation.Valid;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("/stock")
+public class stockController {
+    @Autowired
+    stockService stockService;
+
+    @PostMapping("/deduct")
+    public int deductstock(@Valid @RequestBody StockDeductDTO stockDeductDTO) {
+        return stockService.deductStock(stockDeductDTO.getId(),stockDeductDTO.getDeductNum());
+    }
+}

stock-service/src/main/java/cn/mayiming/Entity/StockDeductDTO.java

@@ -0,0 +1,17 @@
+package cn.mayiming.Entity;
+
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import jakarta.validation.constraints.NotNull;
+import lombok.Data;
+
+@Data
+public class StockDeductDTO {
+    @NotNull
+    @JsonProperty("id")
+    private Long id;
+
+    @NotNull
+    @JsonProperty("deductnum")
+    private Integer deductNum;
+}

stock-service/src/main/java/cn/mayiming/Mapper/StockMapper.java

@@ -0,0 +1,16 @@
+package cn.mayiming.Mapper;
+
+import feign.Param;
+import org.apache.ibatis.annotations.Select;
+import org.apache.ibatis.annotations.Update;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface StockMapper {
+
+    @Select("SELECT stock_num FROM t_stock WHERE goods_id = #{goodsId}")
+    Integer selectStockByGoodsId(@Param("goodsId") Long goodsId);
+
+    @Update("UPDATE t_stock SET stock_num = stock_num - #{deductNum} WHERE goods_id = #{goodsId} AND stock_num >= #{deductNum}")
+    int deductStock(@Param("goodsId") Long goodsId, @Param("deductNum") Integer deductNum);
+}

stock-service/src/main/java/cn/mayiming/Service/stockService.java

@@ -0,0 +1,18 @@
+package cn.mayiming.Service;
+
+
+import cn.mayiming.Mapper.StockMapper;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Service
+public class stockService {
+    @Autowired
+    StockMapper stockMapper;
+
+    @Transactional(rollbackFor = Exception.class)
+    public int deductStock(Long goodsId, int i) {
+        return stockMapper.deductStock(goodsId, i);
+    }
+}

stock-service/src/main/resources/application.yml

@@ -0,0 +1,52 @@
+server:
+  port: 9094
+spring:
+  application:
+    name: stock-service
+  cloud:
+    nacos:
+      # 服务注册发现配置
+      discovery:
+        server-addr: localhost:8848  # Nacos 服务地址（默认端口 8848）
+        namespace: public            # 命名空间（默认 public，自定义需先在 Nacos 控制台创建）
+        group: DEFAULT_GROUP         # 分组（默认 DEFAULT_GROUP）
+        service: stock-service        # 注册到 Nacos 的服务名（建议和子项目 artifactId 一致）
+      # 配置管理配置（如果引入了 config 依赖才需要）
+      config:
+        server-addr: localhost:8848  # 和 discovery 一致
+        file-extension: yaml
+        namespace: public
+        group: DEFAULT_GROUP
+  config:
+    import: nacos:${spring.application.name}.${spring.cloud.nacos.config.file-extension}?server-addr=${spring.cloud.nacos.config.server-addr}
+  datasource:
+    # 数据库驱动类（MySQL 8.x 用 com.mysql.cj.jdbc.Driver，5.x 用 com.mysql.jdbc.Driver）
+    driver-class-name: com.mysql.cj.jdbc.Driver
+    # 数据库连接 URL（替换为你的数据库地址、端口、库名，如 user_db）
+    url: jdbc:mysql://rm-f8z6oc5a03331500p8o.mysql.rds.aliyuncs.com:3306/stock_db?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=Asia/Shanghai&allowPublicKeyRetrieval=true
+    # 数据库用户名（默认 root，根据实际情况修改）
+    username: root
+    # 数据库密码（替换为你的 MySQL 密码）
+    password: Root123456
+    # 可选：连接池配置（推荐使用 HikariCP，Spring Boot 2.x 默认）
+    hikari:
+      # 连接池最大连接数
+      maximum-pool-size: 10
+      # 连接池最小空闲连接数
+      minimum-idle: 2
+      # 连接超时时间（毫秒）
+      connection-timeout: 30000
+      # 连接最大存活时间（毫秒）
+      max-lifetime: 1800000
+#rocketmq:
+#  # NameServer 地址（替换为你的 RocketMQ 服务器IP）
+#  name-server: 127.0.0.1:9876
+#  consumer:
+#    # 消费者组名（必须唯一，建议按服务+用途命名）
+#    group: order-service-consumer
+#    # 消费模式：CONCURRENTLY（并发消费，默认）/ORDERLY（顺序消费）
+#    consume-mode: CONCURRENTLY
+#    # 批量消费最大条数（默认1，单条消费）
+#    consume-message-batch-max-size: 1
+#    # 最大重试次数（消费失败后自动重试，超过次数进入死信队列）
+#    max-reconsume-times: 3