Spring Cloud 入门教程6、Hystrix Dashboard监控数据聚合（Turbine）

一、前言

1、什么是Turbine？

Turbine是Netflix开源的将Server-Sent Event（SSE）的JSON数据流聚合成单个流的工具。我们可以通过Turbine将Hystrix生产的监控数据（JSON）合并到一个流中，方便我们对存在多个实例的应用进行监控。

Turbine can be used with any data source that fits the supported JSON format of key/value pairs delivered via Server Sent Events. However, it is specifically intended for aggregating streams output by Hystrix so that will be used in all examples.

2、本篇环境信息

框架	版本
Spring Boot	2.0.0.RELEASE
Spring Cloud	Finchley.RELEASE
JDK	1.8.x

3、准备工作

参考上一篇：https://ken.io/note/spring-cloud-hystrix-dashboard-quickstart
基于源码：https://github.com/ken-io/springcloud-course/tree/master/chapter-05

准备Eureka Server、服务提供者

启动Eureka Server： http://localhost:8800
启动Test Service：http://localhost:8602

服务消费者+Hystrix Dashboard准备

修改feignclient项目:支持Turbine

上一篇中提到，Hystrix Dashboard是通过指定的URL查看监控信息。
例如：http://localhost:8605/hystrix.stream 可以查看单个应用单个实例的Hystrix监控信息。
也可以通过 [ http://turbine-hostname:port/turbine.stream ] 这样的URL查看聚合的监控信息。

其中Turbine.stream实际上是Turbine（version 1.0）通过访问对应服务每个实例的 http://hystrix-app:port/actuator/hystrix.stream 地址，然后把监控信息聚合起来。所有我们需要添加对应的Servlet注解，以支持通过该URL访问hystrix.stream信息

修改 HystrixConfiguration.java
增加 servletTurbineRegistrationBean() 满足Turbine的读取规则

package io.ken.springcloud.feignclient.configuration;

import com.netflix.hystrix.contrib.metrics.eventstream.HystrixMetricsStreamServlet;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class HystrixConfiguration {

    @Bean(name = "hystrixRegistrationBean")
    public ServletRegistrationBean servletRegistrationBean() {
        ServletRegistrationBean registration = new ServletRegistrationBean(
                new HystrixMetricsStreamServlet(), "/hystrix.stream");
        registration.setName("hystrixServlet");
        registration.setLoadOnStartup(1);
        return registration;
    }

    @Bean(name = "hystrixForTurbineRegistrationBean")
    public ServletRegistrationBean servletTurbineRegistrationBean() {
        ServletRegistrationBean registration = new ServletRegistrationBean(
                new HystrixMetricsStreamServlet(), "/actuator/hystrix.stream");
        registration.setName("hystrixForTurbineServlet");
        registration.setLoadOnStartup(1);
        return registration;
    }
}

启动FeignClient：http://localhost:8605，http://localhost:8606，http://localhost:8607

为了满足测试需要，这次我们启动三个实例。

二、监控数据聚合：Turbine

1、创建Turbine项目

按照惯例，使用maven-archtype-quickstart模板创建项目

项	说明
GroupId	io.ken.springcloud.turbine
ArtifactId	turbine

修改pom.xml 引入相关依赖

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>io.ken.springcloud.turbine</groupId>
    <artifactId>turbine</artifactId>
    <version>1.0-SNAPSHOT</version>

    <name>turbine</name>
    <url>http://ken.io</url>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.0.RELEASE</version>
    </parent>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Finchley.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>

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

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>

    </dependencies>

    <build>
        <finalName>turbine</finalName>
    </build>

</project>

2、配置启动类

修改\src\main\java\io\ken\springcloud\turbine\App.java

@EnableTurbine：启用Turbine
@EnableHystrixDashboard：启用Hystrix Dashboard

package io.ken.springcloud.turbine;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.netflix.hystrix.dashboard.EnableHystrixDashboard;
import org.springframework.cloud.netflix.turbine.EnableTurbine;

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

3、配置Turbine

在\src\main下创建文件夹resources文件夹并设置为Resources Root

在resources文件夹下创建application.yml文件并配置Turbine

server:
  port: 8801

spring:
  application:
    name: turbine

eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:8800/eureka/

turbine:
  app-config: feignclient
  cluster-name-expression: new String("default")
  combine-host-port: true

参数说明：

参数	ken.io的说明
turbine.app-config	指定需要监控的servicename，多个service以,间隔
turbine.cluster-name-expression	指定集群名称，默认为default，当设立了多个集群时，可以在Hystrix指定集群名称来查看监控
turbine.combine-host-port	合并同一个host多个端口的数据