https://github.com/zq2599/blog_demos
经过多篇知识积累终于来到实战章节,亲爱的读者们,请将装备就位,一起动手体验SpringBoot官方带给我们的最新技术;
经过前面的知识积累,我们知道了SpringBoot-2.3新增的探针规范以及适用场景,这里做个简短的回顾:
小结完毕,接下来开始实打实的编码和操作实战,验证上述理论;
本次实战有两个环境:开发和运行环境,其中开发环境信息如下:
运行环境信息如下:
事实证明,用Ubuntu桌面版作为开发环境是可行的,体验十分顺畅,IDEA、SubLime、SSH、Chrome、微信都能正常使用,下图是我的Ubuntu开发环境:
本次实战包括以下内容:
名称 | 链接 | 备注 |
---|---|---|
项目主页 | https://github.com/zq2599/blog_demos | 该项目在GitHub上的主页 |
git仓库地址(https) | https://github.com/zq2599/blog_demos.git | 该项目源码的仓库地址,https协议 |
git仓库地址(ssh) | git@github.com:zq2599/blog_demos.git | 该项目源码的仓库地址,ssh协议 |
<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.3.0.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.bolingcavalry</groupId> <artifactId>probedemo</artifactId> <version>0.0.1-SNAPSHOT</version> <name>probedemo</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <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> <scope>test</scope> <exclusions> <exclusion> <groupId>org.junit.vintage</groupId> <artifactId>junit-vintage-engine</artifactId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>2.3.0.RELEASE</version> <!--该配置会在jar中增加layer描述文件,以及提取layer的工具--> <configuration> <layers> <enabled>true</enabled> </layers> </configuration> </plugin> </plugins> </build> </project>
package com.bolingcavalry.probedemo; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class ProbedemoApplication { public static void main(String[] args) { SpringApplication.run(ProbedemoApplication.class, args); } }
package com.bolingcavalry.probedemo.listener; import lombok.extern.slf4j.Slf4j; import org.springframework.boot.availability.AvailabilityChangeEvent; import org.springframework.boot.availability.AvailabilityState; import org.springframework.context.event.EventListener; import org.springframework.stereotype.Component; /** * description: 监听系统事件的类 <br> * date: 2020/6/4 下午12:57 <br> * author: willzhao <br> * email: zq2599@gmail.com <br> * version: 1.0 <br> */ @Component @Slf4j public class AvailabilityListener { /** * 监听系统消息, * AvailabilityChangeEvent类型的消息都从会触发此方法被回调 * @param event */ @EventListener public void onStateChange(AvailabilityChangeEvent<? extends AvailabilityState> event) { log.info(event.getState().getClass().getSimpleName() + " : " + event.getState()); } }
package com.bolingcavalry.probedemo.controller; import org.springframework.boot.availability.ApplicationAvailability; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import javax.annotation.Resource; import java.util.Date; @RestController @RequestMapping("/statereader") public class StateReader { @Resource ApplicationAvailability applicationAvailability; @RequestMapping(value="/get") public String state() { return "livenessState : " + applicationAvailability.getLivenessState() + "<br>readinessState : " + applicationAvailability.getReadinessState() + "<br>" + new Date(); } }
package com.bolingcavalry.probedemo.controller; import org.springframework.boot.availability.AvailabilityChangeEvent; import org.springframework.boot.availability.LivenessState; import org.springframework.boot.availability.ReadinessState; import org.springframework.context.ApplicationEventPublisher; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import javax.annotation.Resource; import java.util.Date; /** * description: 修改状态的controller <br> * date: 2020/6/4 下午1:21 <br> * author: willzhao <br> * email: zq2599@gmail.com <br> * version: 1.0 <br> */ @RestController @RequestMapping("/staterwriter") public class StateWritter { @Resource ApplicationEventPublisher applicationEventPublisher; /** * 将存活状态改为BROKEN(会导致kubernetes杀死pod) * @return */ @RequestMapping(value="/broken") public String broken(){ AvailabilityChangeEvent.publish(applicationEventPublisher, StateWritter.this, LivenessState.BROKEN); return "success broken, " + new Date(); } /** * 将存活状态改为CORRECT * @return */ @RequestMapping(value="/correct") public String correct(){ AvailabilityChangeEvent.publish(applicationEventPublisher, StateWritter.this, LivenessState.CORRECT); return "success correct, " + new Date(); } /** * 将就绪状态改为REFUSING_TRAFFIC(导致kubernetes不再把外部请求转发到此pod) * @return */ @RequestMapping(value="/refuse") public String refuse(){ AvailabilityChangeEvent.publish(applicationEventPublisher, StateWritter.this, ReadinessState.REFUSING_TRAFFIC); return "success refuse, " + new Date(); } /** * 将就绪状态改为ACCEPTING_TRAFFIC(导致kubernetes会把外部请求转发到此pod) * @return */ @RequestMapping(value="/accept") public String accept(){ AvailabilityChangeEvent.publish(applicationEventPublisher, StateWritter.this, ReadinessState.ACCEPTING_TRAFFIC); return "success accept, " + new Date(); } }
package com.bolingcavalry.probedemo.controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import java.net.Inet4Address; import java.net.InetAddress; import java.net.NetworkInterface; import java.net.SocketException; import java.util.ArrayList; import java.util.Date; import java.util.Enumeration; import java.util.List; /** * description: hello demo <br> * date: 2020/6/4 下午4:38 <br> * author: willzhao <br> * email: zq2599@gmail.com <br> * version: 1.0 <br> */ @RestController public class Hello { /** * 返回的是当前服务器IP地址,在k8s环境就是pod地址 * @return * @throws SocketException */ @RequestMapping(value="/hello") public String hello() throws SocketException { List<Inet4Address> addresses = getLocalIp4AddressFromNetworkInterface(); if(null==addresses || addresses.isEmpty()) { return "empty ip address, " + new Date(); } return addresses.get(0).toString() + ", " + new Date(); } public static List<Inet4Address> getLocalIp4AddressFromNetworkInterface() throws SocketException { List<Inet4Address> addresses = new ArrayList<>(1); Enumeration e = NetworkInterface.getNetworkInterfaces(); if (e == null) { return addresses; } while (e.hasMoreElements()) { NetworkInterface n = (NetworkInterface) e.nextElement(); if (!isValidInterface(n)) { continue; } Enumeration ee = n.getInetAddresses(); while (ee.hasMoreElements()) { InetAddress i = (InetAddress) ee.nextElement(); if (isValidAddress(i)) { addresses.add((Inet4Address) i); } } } return addresses; } /** * 过滤回环网卡、点对点网卡、非活动网卡、虚拟网卡并要求网卡名字是eth或ens开头 * @param ni 网卡 * @return 如果满足要求则true,否则false */ private static boolean isValidInterface(NetworkInterface ni) throws SocketException { return !ni.isLoopback() && !ni.isPointToPoint() && ni.isUp() && !ni.isVirtual() && (ni.getName().startsWith("eth") || ni.getName().startsWith("ens")); } /** * 判断是否是IPv4,并且内网地址并过滤回环地址. */ private static boolean isValidAddress(InetAddress address) { return address instanceof Inet4Address && address.isSiteLocalAddress() && !address.isLoopbackAddress(); } }
以上就是该SpringBoot工程的所有代码了,请确保可以编译运行;
# 指定基础镜像,这是分阶段构建的前期阶段 FROM openjdk:8u212-jdk-stretch as builder # 执行工作目录 WORKDIR application # 配置参数 ARG JAR_FILE=target/*.jar # 将编译构建得到的jar文件复制到镜像空间中 COPY ${JAR_FILE} application.jar # 通过工具spring-boot-jarmode-layertools从application.jar中提取拆分后的构建结果 RUN java -Djarmode=layertools -jar application.jar extract # 正式构建镜像 FROM openjdk:8u212-jdk-stretch WORKDIR application # 前一阶段从jar中提取除了多个文件,这里分别执行COPY命令复制到镜像空间中,每次COPY都是一个layer COPY --from=builder application/dependencies/ ./ COPY --from=builder application/spring-boot-loader/ ./ COPY --from=builder application/snapshot-dependencies/ ./ COPY --from=builder application/application/ ./ ENTRYPOINT ["java", "org.springframework.boot.loader.JarLauncher"]
mvn clean package -U -DskipTests
sudo docker build -t bolingcavalry/probedemo:0.0.1 .
SpringBoot的镜像准备完毕,接下来要让kubernetes环境用上这个镜像;
此时的镜像保存在开发环境的电脑上,可以有以下三种方式加载到kubernetes环境:
以上三种方法的优缺点整理如下:
我的kubernetes环境只有一台电脑,因此用的是方法三,参考命令如下(建议安装sshpass,就不用每次输入帐号密码了):
# 将镜像保存为tar文件 sudo docker save bolingcavalry/probedemo:0.0.1 > probedemo.tar # scp到kubernetes服务器 sshpass -p 888888 scp ./probedemo.tar root@192.168.50.135:/root/temp/202006/04/ # 远程执行ssh命令,加载docker镜像 sshpass -p 888888 ssh root@192.168.50.135 "docker load < /root/temp/202006/04/probedemo.tar"
apiVersion: v1 kind: Service metadata: name: probedemo spec: type: NodePort ports: - port: 8080 nodePort: 30080 selector: name: probedemo --- apiVersion: extensions/v1beta1 kind: Deployment metadata: name: probedemo spec: replicas: 2 template: metadata: labels: name: probedemo spec: containers: - name: probedemo image: bolingcavalry/probedemo:0.0.1 tty: true livenessProbe: httpGet: path: /actuator/health/liveness port: 8080 initialDelaySeconds: 5 failureThreshold: 10 timeoutSeconds: 10 periodSeconds: 5 readinessProbe: httpGet: path: /actuator/health/readiness port: 8080 initialDelaySeconds: 5 timeoutSeconds: 10 periodSeconds: 5 ports: - containerPort: 8080 resources: requests: memory: "512Mi" cpu: "100m" limits: memory: "1Gi" cpu: "500m"
至此,从编码到部署都完成了,接下来验证SpringBoot-2.3.0.RELEASE的探针技术;
kubernetes所在机器的IP地址是192.168.50.135,因此SpringBoot服务的访问地址是http://192.168.50.135:30080/xxx
访问地址http://192.168.50.135:30080/actuator/health/liveness,返回码如下图红框,可见存活探针已开启:
curl http://10.233.90.195:8080/statewriter/accept
https://github.com/zq2599/blog_demos