Springcloud-hystrix断路器实现springcloud（慕课网廖师兄SpringCloud微服务实战）

• 核心依赖

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

• 启用hystrix 断路器

添加@EnableCircuitBreaker注解

@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
@EnableCircuitBreaker
public class MsaWeatherReportServerApplication {

	public static void main(String[] args) {
		SpringApplication.run(MsaWeatherReportServerApplication.class, args);
	}
}

• 注解使用

当服务可用，会走默认的逻辑访问cityClient 当服务不可用，会调用defaultCities方法

• 与feign整合使用

/**
 * @author gaowenfeng
 * @package com.gwf.weather.service
 * @describe Feign访问城市数据API服务接口
 * @date 2018/2/21
 * @FeignClient value 为访问的API名称 fallback 断路器调用，其参数类需要实现DataClient，提供相同的方法调用
 */
@FeignClient(value = "micro-weather-eureka-client",fallback = DataClientFallback.class)
public interface DataClient {

    /**
     * 访问 micro-weather-eureka-client API网关获取城市数据
     * @return
     * @throws Exception
     */
    @GetMapping("city/cities")
    List<City> listCities() throws Exception;

    /**
     * 访问micro-weather-eureka-client API网关 获取天气数据
     * @param cityId
     * @return
     */
    @GetMapping("data/weather/cityId/{cityId}")
    WeatherResponse getDataByCityId(@PathVariable("cityId") String cityId);

}

断路器类

@Component
public class DataClientFallback implements DataClient{
    @Override
    public List<City> listCities() {
        List<City> list = new ArrayList<>();
        City city1 = City.builder().cityId("101280601").cityName("深圳").build();
        City city2 = City.builder().cityId("101280301").cityName("惠州").build();
        list.add(city1);list.add(city2);
        return list;
    }

    @Override
    public WeatherResponse getDataByCityId(String cityId) {
        return null;
    }
}

application.yml

feign:
  client:
    config:
      feignName:
        connectTimeout: 50000
        readTimeout: 50000
  # 启用 feign 的 hystrix断路器  
  hystrix:
    enabled: true