springcloud netflix之学习Hystrix和turbine(4)

Hystrix学习

作用：提供熔断器功能，阻止分布式系统出现联动故障
注意：Feign包中已包含Hystrix

配置

pom.xml

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

application.yml

spring:
  application:
    name: eureka-feign-client
server:
  port: 8765
eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:8761/eureka/
# feign自带hystrix ，开启該功能即可。
feign:
  hystrix:
    enabled: true

client
1.HiHystrix （异常处理类）

@Component
public class HiHystrix implements EurekaClientFeign {
    @Override
    public String sayHiFromClientEureka(String name) {
        return "hi,"+name+",error!!!";
    }
}

2.EurekaClientFeign(配置访问的client和FeignConfig和异常处理类)

@FeignClient(value = "eureka-client",configuration = FeignConfig.class,fallback = HiHystrix.class)
public interface EurekaClientFeign {

    @GetMapping("/hi")
    public String sayHiFromClientEureka(@RequestParam(value = "name") String name);

}

启动类
@EnableEurekaClient
@EnableFeignClients
@EnableHystrixDashboard

turbine学习

作用：同时监控多个熔断状态

配置

pom.xml

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-turbine</artifactId>
        </dependency>

application.yml

turbine:
  aggregator:
    clusterConfig: default   # 指定聚合哪些集群，多个使用","分割，默认为default。可使用http://.../turbine.stream?cluster={clusterConfig之一}访问
  appConfig: eureka-ribbon-client,eureka-feign-client  ### 配置Eureka中的serviceId列表，表明监控哪些服务
  clusterNameExpression: new String("default")
  # 1. clusterNameExpression指定集群名称，默认表达式appName；此时：turbine.aggregator.clusterConfig需要配置想要监控的应用名称
  # 2. 当clusterNameExpression: default时，turbine.aggregator.clusterConfig可以不写，因为默认就是default
  # 3. 当clusterNameExpression: metadata['cluster']时，假设想要监控的应用配置了eureka.instance.metadata-map.cluster: ABC，则需要配置，同时turbine.aggregator.clusterConfig: ABC

client
启动类
@EnableTurbine