微服务Hystrix（六）

断路器

服务熔断

参考cloud-provider-dept-8001工程，创建cloud-provider-dept-hystrix-8001工程

这里只说不同的，首先是pom

    <?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">
        <parent>
            <artifactId>cloud2018</artifactId>
            <groupId>com.tzy.spring</groupId>
            <version>1.0-SNAPSHOT</version>
        </parent>
        <modelVersion>4.0.0</modelVersion>

        <artifactId>cloud-provider-dept-hystrix-8001</artifactId>

        <dependencies>
            <!-- hystrix -->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-hystrix</artifactId>
            </dependency>
            <!-- 将微服务provider侧注册进eureka -->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-eureka</artifactId>
            </dependency>
            <!-- 引入自己定义的api通用包，可以使用Dept部门Entity -->
            <dependency>
                <artifactId>cloud-api</artifactId>
                <groupId>com.tzy.spring</groupId>
                <version>1.0-SNAPSHOT</version>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-config</artifactId>
            </dependency>
            <!-- actuator监控信息完善 -->
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-actuator</artifactId>
            </dependency>
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
            </dependency>
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
            </dependency>
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid</artifactId>
            </dependency>
            <dependency>
                <groupId>ch.qos.logback</groupId>
                <artifactId>logback-core</artifactId>
            </dependency>
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-jetty</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
            </dependency>
            <!-- 修改后立即生效，热部署 -->
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>springloaded</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-devtools</artifactId>
            </dependency>
        </dependencies>
    </project>

>yml文件

server:
  port: 8001

mybatis:
  config-location: classpath:mybatis/mybatis.cfg.xml       # mybatis配置文件所在路径
  type-aliases-package: com.tzy.spring.entities           # 所有Entity别名类所在包
  mapper-locations:
  - classpath:mybatis/mapper/**/*.xml                        # mapper映射文件

spring:
   application:
    name: cloud-dept                                        # 对外暴露的微服务名字   很重要很重要很重要很重要
   datasource:
    type: com.alibaba.druid.pool.DruidDataSource            # 当前数据源操作类型
    driver-class-name: org.gjt.mm.mysql.Driver            # mysql驱动包
    url: jdbc:mysql://localhost:3306/cloudDB01              # 数据库名称
    username: root
    password: root
    dbcp2:
      min-idle: 5                                           # 数据库连接池的最小维持连接数
      initial-size: 5                                       # 初始化连接数
      max-total: 5                                          # 最大连接数
      max-wait-millis: 200                                  # 等待连接获取的最大超时时间

eureka:
  client:                                                    #客户端注册进eureka服务列表内
    service-url:
        #defaultZone: http://localhost:7001/eureka            #单机版是这样，集群是下面那样
       defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/,http://eureka7003.com:7003/eureka/
  instance:
    instance-id: cloud-dept8001-hystrix                    #自身入住服务的别名,网站中间右边的显示名
    prefer-ip-address: true                               #访问路径可以显示IP地址

info:                                                       #点击别名后返回的信息，服务发现后打印的信息
  app.name: lalala
  company.name: www.cnblogs.com/ttzzyy
  build.artifactId: $project.artifactId$
  build.version: $project.version$

> controller修改

	import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
	import com.tzy.spring.entities.Dept;
	import com.tzy.spring.service.DeptService;
	import org.springframework.beans.factory.annotation.Autowired;
	import org.springframework.web.bind.annotation.PathVariable;
	import org.springframework.web.bind.annotation.RequestMapping;
	import org.springframework.web.bind.annotation.RequestMethod;
	import org.springframework.web.bind.annotation.RestController;
	
	@RestController
	public class DeptController
	{
		@Autowired
		private DeptService service = null;
	
		@RequestMapping(value = "/dept/get/{id}", method = RequestMethod.GET)
		//一旦调用服务方法失败并抛出了错误信息后，会自动调用@HystrixCommand标注好的fallbackMethod调用类中的指定方法
		@HystrixCommand(fallbackMethod = "processHystrix_Get")
		public Dept get(@PathVariable("id") Long id)
		{
	
			Dept dept = this.service.get(id);
	
			if (null == dept) {
				throw new RuntimeException("该ID：" + id + "没有没有对应的信息");
			}
	
			return dept;
		}
	
		public Dept processHystrix_Get(@PathVariable("id") Long id)
		{
			return new Dept().setDeptno(id).setDname("该ID：" + id + "没有没有对应的信息,null--@HystrixCommand")
					.setDb_source("no this database in MySQL");
		}
	}

>启动类

package com.tzy.spring;

	import org.springframework.boot.SpringApplication;
	import org.springframework.boot.autoconfigure.SpringBootApplication;
	import org.springframework.cloud.client.circuitbreaker.EnableCircuitBreaker;
	import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
	import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
	
	@SpringBootApplication
	@EnableEurekaClient //本服务启动后会自动注册进eureka服务中
	@EnableDiscoveryClient //服务发现
	@EnableCircuitBreaker//对hystrixR熔断机制的支持
	public class DeptProvider8001_Hystrix_App
	{
		public static void main(String[] args)
		{
			SpringApplication.run(DeptProvider8001_Hystrix_App.class, args);
		}
	}	

>测试看看哇,启动7001-3,当前这个工程，和80工程 [http://localhost/consumer/dept/get/2](http://localhost/consumer/dept/get/2) [http://localhost/consumer/dept/get/255](http://localhost/consumer/dept/get/255)  

服务降级

好了改造工程，首先在消费端打开熔断器，配置yml文件，cloud-consumer-dept-feign工程

server:
  port: 80

feign:
  hystrix:
    enabled: true
  
eureka:
  client:
    register-with-eureka: false    #取消注册自己
    service-url: 
      defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/,http://eureka7003.com:7003/eureka/  

>然后修改cloud-api工程，针对在之前的DeptClientService.java写一个熔断器统一管理， 

	import com.tzy.spring.entities.Dept;
	import feign.hystrix.FallbackFactory;
	import org.springframework.stereotype.Component;
	
	import java.util.List;
	
	@Component // 不要忘记添加，不要忘记添加
	public class DeptClientServiceFallbackFactory implements FallbackFactory<DeptClientService>
	{
		@Override
		public DeptClientService create(Throwable throwable)
		{
			return new DeptClientService() {
				@Override
				public Dept get(long id)
				{
					return new Dept().setDeptno(id).setDname("该ID：" + id + "没有没有对应的信息,Consumer客户端提供的降级信息,此刻服务Provider已经关闭")
							.setDb_source("no this database in MySQL");
				}
	
				@Override
				public List<Dept> list()
				{
					return null;
				}
	
				@Override
				public boolean add(Dept dept)
				{
					return false;
				}
			};
		}
	}

>修改之前的service,指定其需要使用的熔断器

	import com.tzy.spring.entities.Dept;
	import org.springframework.cloud.netflix.feign.FeignClient;
	import org.springframework.web.bind.annotation.PathVariable;
	import org.springframework.web.bind.annotation.RequestMapping;
	import org.springframework.web.bind.annotation.RequestMethod;
	import java.util.List;
	
	
	/**
	 * @Description: 修改cloud-api工程，根据已经有的DeptClientService接口
	 *新建一个实现了FallbackFactory接口的类DeptClientServiceFallbackFactory
	 */
	//@FeignClient(value = "CLOUD-DEPT")
	@FeignClient(value = "CLOUD-DEPT",fallbackFactory=DeptClientServiceFallbackFactory.class)
	public interface DeptClientService
	{
		@RequestMapping(value = "/dept/get/{id}", method = RequestMethod.GET)
		public Dept get(@PathVariable("id") long id);
	
		@RequestMapping(value = "/dept/list", method = RequestMethod.GET)
		public List<Dept> list();
	
		@RequestMapping(value = "/dept/add", method = RequestMethod.POST)
		public boolean add(Dept dept);
	}

>启动7001-3,8001,feign,使用[http://localhost/consumer/dept/get/2](http://localhost/consumer/dept/get/2),访问数据没有问题，然后8001宕机，在次访问  >说明hystrix熔断起了作用。

微服务监控图形化展示

首先我们要把这个大管家搭起来

pom

    <?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">
        <parent>
            <artifactId>cloud2018</artifactId>
            <groupId>com.tzy.spring</groupId>
            <version>1.0-SNAPSHOT</version>
        </parent>
        <modelVersion>4.0.0</modelVersion>

        <artifactId>cloud-provider-dept-hystrix-9001</artifactId>
        <dependencies>
            <!-- 引入自己定义的api通用包，可以使用Dept部门Entity -->
            <dependency>
                <artifactId>cloud-api</artifactId>
                <groupId>com.tzy.spring</groupId>
                <version>1.0-SNAPSHOT</version>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
            <!-- 修改后立即生效，热部署 -->
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>springloaded</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-devtools</artifactId>
            </dependency>
            <!-- Ribbon相关 -->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-eureka</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-ribbon</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-config</artifactId>
            </dependency>
            <!-- feign相关 -->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-feign</artifactId>
            </dependency>
            <!-- hystrix和 hystrix-dashboard相关 -->
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-hystrix</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-hystrix-dashboard</artifactId>
            </dependency>
        </dependencies>

    </project>

>yml

server:
      port: 9001

>启动类

	import org.springframework.boot.SpringApplication;
	import org.springframework.boot.autoconfigure.SpringBootApplication;
	import org.springframework.cloud.netflix.hystrix.dashboard.EnableHystrixDashboard;
	
	@SpringBootApplication
	@EnableHystrixDashboard
	public class DeptProvider9001_Hystrix_App
	{
		public static void main(String[] args)
		{
			SpringApplication.run(DeptProvider9001_Hystrix_App.class, args);
		}
	}

管家配置好了，管谁呢，8001-3，检查这三个工程是否有如下引用。代表被管理

可以启动了
出现下图证明hystrix配置成功http://localhost:9001/hystrix

来看看管家怎么用哇

启动7001-3,hystrix-8001,hystrix-9001
http://localhost:8001/dept/get/2
http://localhost:9001/hystrix
http://localhost:8001/hystrix.stream
发现数据不停的刷新，这是什么呢

看不懂啊，想要图形化的


图形化出来了。爽吧，还是一脸懵逼，怎么看呢？

在使用8001查询，错的查，正确的查 就能看出问题了。

膜拜spring