使用k8s部署项目的流程
容器交付流程
k8s部署项目的流程：
案例：交付一个java应用程序
项目地址：https://github.com/lizhenliang/tomcat-java-demo.git
1. 制作镜像
1.1 编写dockerfile
使用dockerfile的多阶段构建
FROM alpine/git:v2.32.0 as cloner
MAINTAINER "yangsx.yangsx95@qq.com"
WORKDIR /opt
# 拉取代码
RUN git clone https://github.com/lizhenliang/tomcat-java-demo.git
FROM maven:3.8-openjdk-8 as builder
MAINTAINER "yangsx.yangsx95@qq.com"
WORKDIR /opt
# 将cloner阶段的opt/tomcat-java-demo这个文件拷贝到当前阶段的/opt/路径下
COPY --from=cloner /opt/tomcat-java-demo/ /opt/
# 添加阿里云maven镜像
RUN echo '<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 https://maven.apache.org/xsd/settings-1.0.0.xsd"><localRepository>/usr/share/maven/ref/repository</localRepository><mirrors><mirror><id>aliyunmaven</id><mirrorOf>*</mirrorOf><name>阿里云公共仓库</name><url>https://maven.aliyun.com/repository/public</url></mirror></mirrors></settings>' > /opt/settings.xml
# 执行构建
RUN mvn clean package --settings=/opt/settings.xml -Dmaven.test.skip=true
FROM tomcat:8-jdk8 as runner
MAINTAINER "yangsx.yangsx95@qq.com"
WORKDIR /usr/local/tomcat/webapps/
COPY --from=builder /opt/target/*.war /usr/local/tomcat/webapps/ROOT.war1.2 构建镜像到本地
docker build -t yangsx95/hello-girl .测试镜像：
docker run --rm -it yangsx95/hello-girl -p 8080:80801.3 创建harbor项目
1.4 登录harbor
docker login 192.168.121.67注意，如果使用HTTP访问harbor，需要将harbor加入到docker的http仓库白名单中
vim /etc/docker/daemon.json { "insecure-registries": ["ip:端口"] }
1.5 推送镜像到harbor
在habor界面可以看到镜像推送的命令
给镜像打tag，并推送到harbor
docker tag yangsx95/hello-girl:latest 192.168.121.67/hello-girl/hello-girl:v1 docker push 192.168.121.67/hello-girl/hello-girl:v1查看harbor项目
1.6 配置harbor凭据到k8s Secret中
将harbor的登录凭据保存到k8s Secret中，以供k8s服务拉取镜像使用：
kubectl create secret docker-registry harbor-admin \
--docker-username=harbor \
--docker-password=Harbor12345 \
--docker-email=yangsx95@qq.com \
--docker-server=192.168.121.67可以通过如下方式在拉取镜像时使用：
imagePullSecrets:
- name: registry-auth使用kubectl get secrets可以查看Secret是否被正常创建：
kubectl get secrets
NAME TYPE DATA AGE
default-token-zl5r6 kubernetes.io/service-account-token 3 5d1h
harbor-admin kubernetes.io/dockerconfigjson 1 6s
nfs-client-provisioner-token-sntk5 kubernetes.io/service-account-token 3 2d14h2. 使用控制器部署镜像
2.1 部署项目依赖的Mysql数据库
注意，不建议在k8s中部署数据库：
Mysql 属于重量级应用（负载高、吃资源、部署复杂）
Mysql部署难度大，主要针对集群方式，每个集群的角色不同，需要使用StatefulSet
Mysql是比较稳定的服务，极少会更新，享受不到k8s的特性
对服务性能会有一定的衰减，但是Mysql对性能要求很高
可以在k8s中部署单节点，可以享受k8s的快速部署
创建如下mysql deployment资源清单文件 mysql.yml（mysql5.7版本，不支持arm64）：
# 创建Secret，为准备数据库密码配置
apiVersion: v1
kind: Secret
metadata:
name: java-demo-db
namespace: default
type: Opaque
data:
mysql-root-password: "MTIzNDU2"
mysql-password: "MTIzNDU2"
---
# 创建Deployment部署Mysql
apiVersion: apps/v1
kind: Deployment
metadata:
name: java-demo-db
namespace: default
spec:
selector:
matchLabels:
project: www
app: mysql
template:
metadata:
labels:
project: www
app: mysql
spec:
containers:
- name: db
image: mysql:5.7.30
resources:
requests:
cpu: 500m
memory: 512Mi
limits:
cpu: 500m
memory: 512Mi
env:
- name: MYSQL_ROOT_PASSWORD
valueFrom:
secretKeyRef:
name: java-demo-db
key: mysql-root-password
- name: MYSQL_PASSWORD
valueFrom:
secretKeyRef:
name: java-demo-db
key: mysql-password
- name: MYSQL_USER
value: "yangsx"
- name: MYSQL_DATABASE
value: "k8s"
ports:
- name: mysql
containerPort: 3306
livenessProbe:
exec:
command:
- sh
- -c
- "mysqladmin ping -u root -p${MYSQL_ROOT_PASSWORD}"
initialDelaySeconds: 30
periodSeconds: 10
readinessProbe:
exec:
command:
- sh
- -c
- "mysqladmin ping -u root -p${MYSQL_ROOT_PASSWORD}"
initialDelaySeconds: 5
periodSeconds: 10
volumeMounts:
- name: data
mountPath: /var/lib/mysql
volumes:
- name: data
persistentVolumeClaim:
claimName: java-demo-db
---
# 配置PVC，使用nfs动态分配PV
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: java-demo-db
namespace: default
spec:
storageClassName: "managed-nfs-storage"
accessModes:
- "ReadWriteOnce"
resources:
requests:
storage: "8Gi"
---
# 配置Service为集群其他pod提供服务
apiVersion: v1
kind: Service
metadata:
name: java-demo-db
namespace: default
spec:
type: ClusterIP
ports:
- name: mysql
port: 3306
targetPort: mysql
selector:
project: www
app: mysql执行部署并查看部署结果：
$ kubectl apply -f mysql.yaml
$ kubectl get svc java-demo-db
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
java-demo-db ClusterIP 10.103.36.119 <none> 3306/TCP 2m19s测试mysql是否正常连接（使用mysql-client镜像）：
$ kubectl run mysql-client --rm -it --image=mysql:5.7.30 -- bash
If you don't see a command prompt, try pressing enter.
root@mysql-client:/# mysql -h 10.101.140.88 -uroot -p123456
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 99
Server version: 5.7.30 MySQL Community Server (GPL)
Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| k8s |
| mysql |
| performance_schema |
| sys |
+--------------------+
5 rows in set (0.07 sec)2.2 导入项目sql文件
准备sql文件：https://github.com/lizhenliang/tomcat-java-demo/blob/master/db/tables_ly_tomcat.sql
将该sql文件下载并拷贝到mysql-client中：
kubectl cp tables_ly_tomcat.sql mysql-client:/在mysql-client中使用mysql命令导入到数据库中：
mysql> create database test;
Query OK, 1 row affected (0.09 sec)
mysql> use test;
Database changed
mysql> source /tables_ly_tomcat.sql
Query OK, 1 row affected, 1 warning (0.02 sec)
Database changed
Query OK, 0 rows affected (0.12 sec)
Query OK, 0 rows affected (0.00 sec)
mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| user |
+----------------+
1 row in set (0.01 sec)2.3 创建ConfigMap保存项目配置文件
创建一个ConfigMap，它拥有一个 application.yml键，用于对应spring-boot项目的根配置，其内容拷贝自https://github.com/lizhenliang/tomcat-java-demo/blob/master/src/main/resources/application.yml：
apiVersion: v1
kind: ConfigMap
metadata:
name: java-demo-config
data:
application.yml: |
server:
port: 8080
spring:
datasource:
url: jdbc:mysql://localhost:3306/test?characterEncoding=utf-8
username: root
password: 123456789
driver-class-name: com.mysql.jdbc.Driver
freemarker:
allow-request-override: false
cache: true
check-template-location: true
charset: UTF-8
content-type: text/html; charset=utf-8
expose-request-attributes: false
expose-session-attributes: false
expose-spring-macro-helpers: false
suffix: .ftl
template-loader-path:
- classpath:/templates/
2.4 创建deployment
apiVersion: apps/v1
kind: Deployment
metadata:
name: java-demo
spec:
replicas: 1
selector:
matchLabels:
project: www
app: java-demo
template:
metadata:
labels:
project: www
app: java-demo
spec:
# 指定镜像拉取的所需要的secret
imagePullSecrets:
- name: registry-auth
containers:
- image: 192.168.121.67/microservice/java-demo:v1
name: java-demo
volumeMounts:
- name: config
mountPath: "/usr/local/tomcat/webapps/ROOT/WEB-INF/classes/application.yml"
subPath: application.yml
resources:
requests:
cpu: 0.5
memory: 500Mi
limits:
cpu: 1
memory: 1Gi
livenessProbe:
httpGet:
path: /
port: 8080
initialDelaySeconds: 50
periodSeconds: 10
readinessProbe:
httpGet:
path: /
port: 8080
initialDelaySeconds: 50
periodSeconds: 10
volumes:
- name: config
configMap:
name: java-demo-config
items:
- key: "application.yml"
path: "application.yml"
一般必须配置的几个属性：
环境变量
资源配额 （重要）
健康检查
卷挂载点
3. 对外暴露应用
3.1 配置Service
apiVersion: v1
kind: Service
metadata:
name: java-demo
spec:
selector:
project: www
app: java-demo
ports:
- protocol: TCP
port: 80
targetPort: 8080 3.2 配置Ingress
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: java-demo
annotations:
kubernetes.io/ingress.class: "nginx"
spec:
rules:
- host: hello.girl.com # 将域名映射到 java-web 服务
http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: java-web # 将所有请求发送到 java-web 服务的 8080 端口
port:
number: 8080 3.3 增加公网负载均衡
upstream ingress-controller {
server 192.168.121.11:80;
server 192.168.121.12:80;
}
server {
listen 80;
server_name: _;
location /{
proxy_pass http://ingress-controller;
proxy_set_header Host $Host; # $Host是浏览器访问网址时指定的域名
}
}最后更新于
