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Feign对Sentinel的支持

feign:
  sentinel:
    enabled: true

 3.定义Feign接口实现类（容错类&