OpenFeign整合Sentinel

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <!-- nacos服务发现 -->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
    </dependency>
 
    <!-- openfeign 服务调用 -->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-openfeign</artifactId>
    </dependency>
    <!--sentinel 服务保护 -->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
    </dependency>
</dependencies>

spring:
  application:
    name: order-feign-sentinel
  cloud:
    nacos:
      server-addr: 127.0.0.1:8847
      discovery:
        username: nacos
        password: nacos
 
# springboot 默认日志级别是info  因此 feign的debug日志级别就不会输出
logging:
  level:
    com.learning.springcloud.order.feign: debug
 
# openfeign 整合 sentinel
feign:
  sentinel:
    enabled: true

stock-nacos 接口类
@RestController
@RequestMapping("/stock")
public class StockController {
    @Value("${server.port}")
    String serverPort;
 
    @RequestMapping("/reduct2")
    public Object reductStock2() {
        int a = 1 / 0; // 故意制造异常
        System.out.println(serverPort + ":扣减库存2成功了");
        return "reduct2 stock success. stock service port:" + serverPort;
    }
}
OpenFeigin 接口类

@FeignClient(name = "stock-nacos", path = "/stock", configuration = FeignConfig.class)
public interface StockFeignService {
    
    @RequestMapping("/reduct2")
    String reductStock2();
}
服务降级处理类  实现OpenFeigin 接口类 并 托管Spring容器

@Component
public class StockFeignServiceForback implements StockFeignService {
    @Override
    public String reductStock2() {
        return "降级了!!!";
    }
}
OpenFeign 接口类 增加  fallback 属性， 值为服务降级处理类

// fallback = StockFeignServiceForback.class
@FeignClient(name = "stock-nacos", path = "/stock", configuration = FeignConfig.class,
        fallback = StockFeignServiceForback.class)
public interface StockFeignService {
    @RequestMapping("/reduct2")
    String reductStock2();
}