sentinel和openfeign整合

1.引入依赖

<!--nacos 服务注册发现-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <!--openfeign-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <!--服务容错-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
        </dependency>

2.开启sentinel支持

服务消费者配置文件中开启对Sentinel的支持

feign:
  sentinel:
    enabled: true

 3.定义Feign接口实现类（容错类），用于服务降级

package per.pz.openfeign;

import org.springframework.stereotype.Component;

@Component
public class StockFeignServiceFallback implements StockFeignService{
    @Override
    public String reduct(){
        return "Fallback,降级了";
    }
}

4.指定容错类

为OpenFeign远程调用接口添加fallback属性值指定容错类

package per.pz.openfeign;

import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.stereotype.Component;
import org.springframework.stereotype.Service;
import org.springframework.web.bind.annotation.RequestMapping;

/**
 * name指定调用rest接口所对应的服务名
 * path指定调用rest接口所在的StockController指定的RequestMapping
 */
@Service
@FeignClient(name = "stock-service",path = "/stock",fallback = StockFeignServiceFallback.class)
public interface StockFeignService {
    //声明需要调用的rest接口对应的方法
    @RequestMapping("/reduct")
    String reduct();
}

/**
 @RestController
 @RequestMapping("stock")
 public class stockController {
 //读取配置文件中的端口
 @Value("${server.port}")
 String port;
 @RequestMapping("/reduct")
 public String reduct(){
 System.out.println("扣减库存");
 return "扣减库存111"+port;
 }
 }
 */