springcloud中feign声明式服务和hystrix请求熔断和服务降级

一、配置

pom文件引入依赖

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
</dependency>

启动类配置

@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
@EnableCircuitBreaker
public class StartCloudFeignApplication {
    public static void main(String[] args) {
        SpringApplication.run(StartCloudFeignApplication.class,args);
    }
}

feign常用配置

feign:
  hystrix:
    enabled: true #在Feign中开启Hystrix
  compression:
    request:
      enabled: false #是否对请求进行GZIP压缩
      mime-types: text/xml,application/xml,application/json #指定压缩的请求数据类型
      min-request-size: 2048 #超过该大小的请求会被压缩
    response:
      enabled: false #是否对响应进行GZIP压缩

hystrix:

  command:
    default:  #default全局有效，service id指定应用有效
      execution:
        timeout:
          enabled: false
        isolation:
          thread:
            timeoutInMilliseconds: 3000 #断路器超时时间，默认1000ms

 二、服务降级示例

@FeignClient(name = "cloud-web1",fallback = CloudWebHystrixImpl.class)
public interface ICloudWebFeign {
    @GetMapping("/test1")
    public String test1();
}

@Component
public class CloudWebHystrixImpl implements ICloudWebFeign {
    @Override
    public String test1() {
        return "调用失败，服务降级";
    }
}