Hystrix监控面板dashboard

1.版本描述

• spring-boot：2.1.9.RELEASE
• spring-cloud: Greenwich.SR3

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2.示例结构

结构图.png

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3.代码

3.1eureka注册中心

• 主要依赖

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

• 启动类

@EnableEurekaServer
@SpringBootApplication
public class EurekaServerApplication {
    public static void main(String[] args) {
        SpringApplication.run(EurekaServerApplication.class, args);
    }
}

• application.properties

spring.application.name=eureka-server
server.port=8761
eureka.client.service-url.defaultZone=http://localhost:8761/eureka/
eureka.client.register-with-eureka=false
eureka.client.fetch-registry=false
eureka.server.enable-self-preservation=false

访问http://localhost:8761/启动eureka注册中心

3.2服务提供端(一共有两个)

3.2.1 第一个

• 主要依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
 </dependency>

• 启动类

@EnableEurekaClient
@SpringBootApplication
public class ScProviderApplication {
    public static void main(String[] args) {
        SpringApplication.run(ScProviderApplication.class, args);
    }
}

• 接口层

@Slf4j
@RestController
public class MultiplyController {

    @Value("${spring.application.name}")
    private String name;

    @Value("${server.port}")
    private String port;

    @RequestMapping(value = "/multi",method = RequestMethod.GET)
    public Integer multiply(@RequestParam("a") int a,@RequestParam("b") int b){

        log.info("{}服务-端口：{}的multiply方法被调用---"+ LocalDateTime.now(),name,port);
        return a*b;
    }
}

• application.properties

spring.application.name=service-multiply
server.port=7777
eureka.instance.prefer-ip-address=true
eureka.instance.instance-id=${spring.cloud.client.ip-address}:${server.port}
eureka.client.service-url.defaultZone=http://localhost:8761/eureka/

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3.2.2 第二个

• 主要依赖
  与第一个相同
• 启动类
  与第一个相同
• 接口层
  与第一个相同
• application.properties

spring.application.name=service-multiply
server.port=7778
eureka.instance.prefer-ip-address=true
eureka.instance.instance-id=${spring.cloud.client.ip-address}:${server.port}
eureka.client.service-url.defaultZone=http://localhost:8761/eureka/

启动两个服务端

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3.3服务消费端

• 主要依赖

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <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.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
            <version>2.1.3.RELEASE</version>
        </dependency>

• 启动类

@EnableFeignClients
@SpringCloudApplication
public class ScFeignApplication {
    public static void main(String[] args) {
        SpringApplication.run(ScFeignApplication.class, args);
    }
}

• 接口层

@Slf4j
@RestController
public class MultiplyController {

    @Autowired
    private GetMultiply getMultiply;

    @Autowired
    private ServiceInstance serviceInstance;

    @RequestMapping(value = "/multi",method = RequestMethod.GET)
    public Integer multiply(){

        log.info("{}服务-端口：{}的multiply方法被调用---"+ LocalTime.now(),serviceInstance.getServiceId(),serviceInstance.getPort());
        return getMultiply.multiply(1,2);
    }
}

• GetMultiply 类

@FeignClient(value = "service-multiply",fallback = GetMultiplyImpl.class)
public interface GetMultiply {
    @RequestMapping(value = "/multi",method = RequestMethod.GET)
    Integer multiply(@RequestParam("a") int a, @RequestParam("b") int b);
}

• GetMultiplyImpl类

@Slf4j
@Component
public class GetMultiplyImpl implements GetMultiply {

    @Autowired
    private ServiceInstance serviceInstance;

    @Override
    public Integer multiply(int a, int b) {
        log.error("{}服务-端口：{}调用报错！！",serviceInstance.getServiceId(),serviceInstance.getPort());
        return 0;
    }
}

• application.properties

spring.application.name=feign
server.port=8887
eureka.instance.prefer-ip-address=true
eureka.instance.instance-id=${spring.cloud.client.ip-address}:${server.port}
eureka.client.service-url.defaultZone=http://localhost:8761/eureka/
feign.hystrix.enabled=true
management.endpoints.enabled-by-default=true
management.endpoints.web.exposure.include=*

启动消费端

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3.4Hystrix-dashboard

• 主要依赖

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

• 启动类

@EnableEurekaClient
@EnableHystrixDashboard
@SpringBootApplication
public class SpringCloudDashboardApplication {
    public static void main(String[] args) {
        SpringApplication.run(SpringCloudDashboardApplication.class, args);
    }
}

• application.properties

spring.application.name=hystrix-dashboard
server.port=9999
eureka.instance.prefer-ip-address=true
eureka.instance.instance-id=${spring.cloud.client.ip-address}:${server.port}
eureka.client.service-url..defaultZone=http://localhost:8761/eureka/

启动hystrix-dashboard，访问http://localhost:9999/hystrix将进入监控面板主页面，页面如下：

hystrix-dashboard主页面.png

在监控地址中输入http://localhost:8887/actuator/hystrix.stream

• Dalay:延迟时间
• Title： 显示的标题
  点击Monitor Stream，进入页面如下：
  bashboard监控页面.png

如果页面展示的是loading...，那么需要先访问一下服务消费端的接口，此demo的是http://localhost:8887/multi,然后监控页面就会显示正常

对于页面各部分代表的含义，可以参考管网wiki，部分截图如下：

代表含义.png

4.本demo中可能出现的bug

描述：Unable to connect to Command Metric Stream.
问题所在：
没有给监控的服务添加如下依赖：

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

然后启动类如下：

@EnableFeignClients
@SpringCloudApplication
public class ScFeignApplication {
    public static void main(String[] args) {
        SpringApplication.run(ScFeignApplication.class, args);
    }
}

启动类中的@EnableFeignClients不是必要的，根据自己的需要决定，此demo中用了两个服务生产者，所以使用了feign，重点是要有开启断路器的注解@EnableCircuitBreaker,@SpringCloudApplication注解的源代码如下：

@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@SpringBootApplication
@EnableDiscoveryClient
@EnableCircuitBreaker
public @interface SpringCloudApplication {

}

同时要注意application.properties文件是有有开启断路器的配置

feign.hystrix.enabled=true

现在hystrix-dashboard基本都是和turbine一起使用的，毕竟hystrix-dashboard只能监控单体应用，而turbine可以监控多个，有兴趣的话可以参考spring cloud 聚合监控Turbine这篇文章，这篇文章也是建立在本文的基础之上的。

5.代码地址
eureka：https://gitee.com/xiongzelin/eureka-seever.git
服务提供端：

• 第一个：https://gitee.com/xiongzelin/sc-provider.git
• 第二个: https://gitee.com/xiongzelin/sc-provider-peer1.git
  服务消费端：https://gitee.com/xiongzelin/sc-feign.git
  hystrix-bashboard:https://gitee.com/xiongzelin/spring-cloud-dashboard.git