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