41.Sentinel
Feign 整合 Sentinel
依赖
<!--Feign-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
<!--sentinel-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
</dependency>
application.properties
# Feign 整合 Sentinel
feign.sentinel.enabled=true
UserCenterFeignClient
@FeignClient(
name = "user-center",
// fallback = UserCenterFeignClientFallback.class
fallbackFactory = UserCenterFeignClientFallbackFactory.class
)
public interface UserCenterFeignClient {
@GetMapping("/users/{id}")
UserDTO queryById(@PathVariable("id") Integer id);
}
UserCenterFeignClientFallback
# 注意一定要加@Component
@Component
public class UserCenterFeignClientFallback implements UserCenterFeignClient {
@Override
public UserDTO queryById(Integer id) {
UserDTO userDTO = new UserDTO();
userDTO.setWxNickname("默认用户");
return userDTO;
}
}
UserCenterFeignClientFallbackFactory
@Component
@Slf4j
public class UserCenterFeignClientFallbackFactory implements FallbackFactory<UserCenterFeignClient> {
@Override
public UserCenterFeignClient create(Throwable throwable) {
return new UserCenterFeignClient() {
@Override
public UserDTO queryById(Integer id) {
log.warn("远程调用被限流/降级了", throwable);
UserDTO userDTO = new UserDTO();
userDTO.setWxNickname("默认用户");
return userDTO;
}
};
}
}
FallbackFactory 比 Fallback 更强大,可以打印更多异常信息。
源码: