在 Kubernetes 中部署 SpringBoot 应用

不念不忘少年蓝@ 2022-05-04 08:30 309阅读 0赞

# 在 Kubernetes 中部署 SpringBoot 应用 #

> 在 Kubernetes 中通过yaml 配置文件预先声明部署 SpringBoot 应用

> 代码地址 [https://github.com/helloworlde/k8s-service][https_github.com_helloworlde_k8s-service]

## 创建 SpringBoot 应用 ##

*  创建名为 k8s-service 的 SpringBoot 应用
 *  添加 REST API
    
     *  K8sController.java

package cn.com.hellowood.k8sservice.controller;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    @RestController
    @RequestMapping("/")
    public class K8sController { 
    
        @GetMapping("/")
        public String root() { 
            return "Hello Kubernetes";
        }
    
        @GetMapping("/healthz")
        public String healthz() { 
            return "ok";
        }
    }

*  添加 Dockerfile

FROM openjdk:8-jdk-alpine
    VOLUME /tmp
    ENV TZ=Asia/Shanghai
    RUN ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && echo $TZ > /etc/timezone
    ARG JAR_FILE
    ADD ${JAR_FILE} app.jar
    ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom", "-Duser.timezone=GMT+08", "-jar","/app.jar"]

*  编译打包

./gradlew clean build -x test

*  生成并推送镜像

./gradlew dockerPush -i

## 在 Kubernetes 中添加服务 ##

*  添加 k8s-demo.yaml

apiVersion: v1
    kind: Service
    metadata:
      name: k8s-service
      namespace: default
      labels:
        app: k8s-service
    spec:
      type: NodePort
      ports:
      - port: 8080
        nodePort: 30002
      selector:
        app: k8s-service
    
    ---
    
    apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: k8s-service
      labels:
        app: k8s-service
    spec:
      replicas: 1
      selector:
        matchLabels:
          app: k8s-service
      template:
        metadata:
          labels:
            app: k8s-service
        spec:
          containers:
          - name: k8s-service
            image: registry.cn-qingdao.aliyuncs.com/hellowoodes/k8s-service
            imagePullPolicy: IfNotPresent
            ports:
            - containerPort: 8080
            livenessProbe:
              httpGet:
                port: 8080
                path: /healthz
                scheme: HTTP
              periodSeconds: 15
              initialDelaySeconds: 30

*  创建服务

kubectl apply -f k8s-service.yaml

*  等待服务启动之后访问 `${NodeIP}:30002`，会返回 `Hello Kubernetes`，部署完成

[https_github.com_helloworlde_k8s-service]: https://github.com/helloworlde/k8s-service