1，微服務之間是通過Fegin進行呼叫，建立了一個呼叫介面，當開啟熔斷機制之後，會造成無法啟動和編譯

2，託底函式問題就出現在託底函式上面

 1 @FeignClient(name = "service-vod",fallback = VodFileDegradeFeignClient.class)
 2 @Component
 3 public interface VodClient {
 4 
 5     /**
 6      * 根據視訊id刪除網路視訊,（遠端呼叫）
 7      * @param videoId
 8      * @return
 9      */
10     @DeleteMapping("/eduvod/video/delete/{videoId}")
 
11     R removeVideo(@PathVariable("videoId") String videoId);
12 
13 
14     /**
15      * 根據id列表刪除網路視訊,(遠端呼叫)
16      * @param videoIdList
17      * @return
18      */
19     @DeleteMapping("/eduvod/video/deleteBatch")
20     R deleteBatch(@RequestParam("videoIdList") List<String> videoIdList);
21
 
 
22 }

3，報錯情況，原因是找不到託底函式

1 Caused by: java.lang.IllegalStateException: No fallback instance of type class com.jouyo.eduservice.client.VodFileDegradeFeignClient found for feign client service-vod
2     at org.springframework.cloud.openfeign.HystrixTargeter.getFromContext(HystrixTargeter.java:81)
3     at org.springframework.cloud.openfeign.HystrixTargeter.targetWithFallback(HystrixTargeter.java:72)
 
4     at org.springframework.cloud.openfeign.HystrixTargeter.target(HystrixTargeter.java:49)
5     at org.springframework.cloud.openfeign.FeignClientFactoryBean.loadBalance(FeignClientFactoryBean.java:253)
6     at org.springframework.cloud.openfeign.FeignClientFactoryBean.getTarget(FeignClientFactoryBean.java:282)
7     at org.springframework.cloud.openfeign.FeignClientFactoryBean.getObject(FeignClientFactoryBean.java:262)
8     at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:171)
9     ... 59 common frames omitted

4，解決方案，在你的遠端呼叫實現類上加上註解

1 @Service
2 public class VodFileDegradeFeignClient implements VodClient {
3     //*********
4 }