Feign 组件的 fallback 操作
开启hystrix 熔断器
application.yml
feign:
hystrix:
enabled: true
方式一：简单，但无法获取异常信息和异常号
FeignClient类
@FeignClient(value = "eureka-client-express-message", fallback = MessageClientHystrix.class)
public interface MessageClient {
@GetMapping("/express-message/getMessageUnRead/{account}")
R getMessageUnRead(@PathVariable String account);
@GetMapping("/express-message/test")
String test();
}
Hystrix类：重写方法用于当接口访问异常时，即调用的接口抛出异常时调用对应的重写方法，一般用于容错返回和输出异常
@Slf4j
@Component
public class MessageClientHystrix implements MessageClient {
@Override
public R getMessageUnRead(String account) {
return R.failed();
}
@Override
public String test() {
log.error("Hystrix error ! ");
return "";
}
}
被调用服务的控制器
@RestController
public class TestController {
@GetMapping("/test")
public String test() {
throw new RuntimeException("服务端测试异常！");
// return "test";
}
}
调用方服务的控制器
@RestController
public class TestController {
@Resource
MessageClient messageClient;
@GetMapping("/test")
public String test(){
return messageClient.test();
}
}
方式二：用Factory，可以获取异常信息和异常号
MessageFeignFactory类
@Component
public class MessageFeignFactory implements FallbackFactory<MessageClient> {
private final MessageClientHystrix messageClientHystrix;
public MessageFeignFactory(MessageClientHystrix messageClientHystrix) {
this.messageClientHystrix = messageClientHystrix;
}
@Override
public MessageClient create(Throwable throwable) {
throwable.printStackTrace();
return messageClientHystrix;
}
}
修改@FeignClient 注解
@FeignClient(value = "eureka-client-express-message", fallbackFactory = MessageFeignFactory.class)
public interface MessageClient {
@GetMapping("/express-message/getMessageUnRead/{account}")
R getMessageUnRead(@PathVariable String account);
@GetMapping("/express-message/test")
String test();
}
其他的不用修改
运行结果
可以看到抛出的异常有状态号信息等
