Feign中使用hystrix

在前面Feign整合Ribbon负载均衡的基础上（Feign整合Ribbon负载均衡），Feigin再整合Hystrix断路

一、backend_show_consumer工程

该工程的依赖如下

1、工程中的application.yml中增加配置

feign:
  hystrix:
    enabled: true

　　

2、增加接口ProviderApi，对应backend_show_provider中的提供的两个接口

@FeignClient(name = "hello-service-provider",
        path = "/provider",
        fallback = ProviderFallbackAPIImpl.class
public interface ProviderApi {

    @RequestMapping(value = "/sayhello")
    String invokerProviderController(@RequestParam("message")String message);

    @RequestMapping(value = "/{providerId}/sayhello", method = RequestMethod.POST)
    String invokerProvider(
            @RequestHeader("author") String author,
            @PathVariable("providerId") String providerId,
            @RequestBody UserModel json);
}

　　设置fallback = ProviderFallbackAPIImpl.class

3、降级实现：ProviderFallbackAPIImpl类

//降级实现
@Component
public class ProviderFallbackAPIImpl implements  ProviderApi {
    @Override
    public String invokerProviderController(String message) {
        return "invokerProviderController fallback message=" +message;
    }

    @Override
    public String invokerProvider(String author, String providerId, UserModel json) {
        return "invokerProvider fallback auth=" +author + ",providerId=" + providerId +",json=" +json;
    }

　　

4、Controller方法

@Slf4j
@RestController
public class ConsumerController {

    @Resource
    private ConsumerServiceAPI serviceAPI;

    @Resource
    private ProviderApi providerApi;

    @RequestMapping(value = "/sayhello/feign")
    public String sayHelloFeign(String message){
        System.out.println("feign message=" + message);
        return  providerApi.invokerProviderController(message);
    }

    @RequestMapping(value = "/sayhello/post")
    public String sayHelloPost( String author,
                                 String providerId,
                                UserModel json){
        log.info("author:{},providerId;{}, userModel:{}", author, providerId, json);

        return  providerApi.invokerProvider(author, providerId, json);
    }

    @RequestMapping(value = "/sayhello")
    public String sayHello(String message){
        return  serviceAPI.sayHello(message);
    }

}

　　

二、启动eureka服务（略）

三、启动backend_show_provider

四、测试

1、此时访问正常

或者

此时说明Feign整合Ribbon负载均衡器

2、停止backend_show_provider服务，这样backend_show_customer访问backend_show_provider就会超时，触发熔断

此时说明Feign整合Hystrix断路器

五、另外一种实现方式fallbackFactory

1、增加fallbackFactory配置

2、FallbackFactory 实现如下

@Component
public class FallbackFactory implements feign.hystrix.FallbackFactory {
    @Override
    public ProviderApi create(Throwable throwable) {
        return new ProviderApi() {
            @Override
            public String invokerProviderController(String message) {
                  return "invokerProviderController FallbackFactory message=" +message;
            }

            @Override
            public String invokerProvider(String author, String providerId, UserModel json) {
                return "invokerProvider FallbackFactory auth=" +author + ",providerId=" + providerId +",json=" +json;

            }
        };
    }
}

　　

3、调用