微服务架构：使用Docker+Kubernetes部署应用

微服务架构使用DockerKubernetes部署应用大家好我是欧阳瑞Rich Own。今天想和大家聊聊微服务架构以及如何使用Docker和Kubernetes进行部署。作为一个全栈开发者我经历过单体应用到微服务的转型深刻体会到微服务带来的好处。什么是微服务架构微服务架构是一种将应用程序拆分成多个小型、独立服务的架构风格。每个服务独立部署独立扩展拥有自己的数据库通过API进行通信微服务的优势优势说明独立部署一个服务更新不会影响其他服务技术多样性不同服务可以使用不同技术栈弹性扩展可以根据需求独立扩展每个服务容错性单个服务故障不会导致整个系统崩溃团队自治每个团队可以独立负责一个服务Docker入门什么是DockerDocker是一个容器化平台可以将应用及其依赖打包成一个独立的容器。安装Docker# Ubuntu/Debian curl -fsSL https://get.docker.com -o get-docker.sh sudo sh get-docker.sh # Mac brew install docker # 验证安装 docker --version创建Dockerfile# 使用Node.js官方镜像作为基础镜像 FROM node:18-alpine # 设置工作目录 WORKDIR /app # 复制package.json和package-lock.json COPY package*.json ./ # 安装依赖 RUN npm ci --onlyproduction # 复制应用代码 COPY . . # 暴露端口 EXPOSE 3000 # 启动命令 CMD [node, server.js]构建和运行容器# 构建镜像 docker build -t my-node-app . # 运行容器 docker run -p 3000:3000 my-node-app # 后台运行 docker run -d -p 3000:3000 my-node-app # 查看运行中的容器 docker ps # 查看日志 docker logs container-idDocker Compose什么是Docker ComposeDocker Compose可以定义和运行多个容器的应用。创建docker-compose.ymlversion: 3.8 services: web: build: . ports: - 3000:3000 environment: - NODE_ENVproduction - DATABASE_URLpostgres://user:passworddb:5432/mydb depends_on: - db restart: unless-stopped db: image: postgres:15-alpine volumes: - postgres_data:/var/lib/postgresql/data environment: - POSTGRES_USERuser - POSTGRES_PASSWORDpassword - POSTGRES_DBmydb restart: unless-stopped volumes: postgres_data:运行Docker Compose# 启动所有服务 docker-compose up -d # 查看服务状态 docker-compose ps # 查看日志 docker-compose logs -f # 停止服务 docker-compose downKubernetes入门什么是KubernetesKubernetes简称K8s是一个容器编排平台可以自动化部署、扩展和管理容器化应用。安装Minikube本地开发# 安装Minikube curl -LO https://storage.googleapis.com/minikube/releases/latest/minikube-darwin-amd64 sudo install minikube-darwin-amd64 /usr/local/bin/minikube # 启动Minikube minikube start # 安装kubectl brew install kubectl # 验证安装 kubectl cluster-info创建Deployment# deployment.yaml apiVersion: apps/v1 kind: Deployment metadata: name: web-deployment labels: app: web spec: replicas: 3 selector: matchLabels: app: web template: metadata: labels: app: web spec: containers: - name: web image: my-node-app:latest ports: - containerPort: 3000 env: - name: NODE_ENV value: production - name: DATABASE_URL value: postgres://user:passwordpostgres-service:5432/mydb resources: requests: memory: 128Mi cpu: 250m limits: memory: 256Mi cpu: 500m创建Service# service.yaml apiVersion: v1 kind: Service metadata: name: web-service spec: selector: app: web ports: - port: 80 targetPort: 3000 type: LoadBalancer创建StatefulSet数据库# statefulset.yaml apiVersion: apps/v1 kind: StatefulSet metadata: name: postgres spec: serviceName: postgres-service replicas: 1 selector: matchLabels: app: postgres template: metadata: labels: app: postgres spec: containers: - name: postgres image: postgres:15-alpine ports: - containerPort: 5432 env: - name: POSTGRES_USER value: user - name: POSTGRES_PASSWORD value: password - name: POSTGRES_DB value: mydb volumeMounts: - name: postgres-data mountPath: /var/lib/postgresql/data volumeClaimTemplates: - metadata: name: postgres-data spec: accessModes: [ ReadWriteOnce ] resources: requests: storage: 10Gi应用配置# 应用Deployment kubectl apply -f deployment.yaml # 应用Service kubectl apply -f service.yaml # 应用StatefulSet kubectl apply -f statefulset.yaml # 查看Pod状态 kubectl get pods # 查看Service kubectl get services # 查看日志 kubectl logs pod-name # 进入Pod kubectl exec -it pod-name -- /bin/shKubernetes进阶水平自动扩展# hpa.yaml apiVersion: autoscaling/v2 kind: HorizontalPodAutoscaler metadata: name: web-hpa spec: scaleTargetRef: apiVersion: apps/v1 kind: Deployment name: web-deployment minReplicas: 3 maxReplicas: 10 metrics: - type: Resource resource: name: cpu target: type: Utilization averageUtilization: 70 - type: Resource resource: name: memory target: type: Utilization averageUtilization: 80配置管理# configmap.yaml apiVersion: v1 kind: ConfigMap metadata: name: app-config data: NODE_ENV: production API_URL: https://api.example.com# secret.yaml apiVersion: v1 kind: Secret metadata: name: app-secret type: Opaque data: DATABASE_PASSWORD: cGFzc3dvcmQ # base64 encoded健康检查apiVersion: apps/v1 kind: Deployment metadata: name: web-deployment spec: template: spec: containers: - name: web image: my-node-app:latest ports: - containerPort: 3000 livenessProbe: httpGet: path: /health port: 3000 initialDelaySeconds: 30 periodSeconds: 10 readinessProbe: httpGet: path: /ready port: 3000 initialDelaySeconds: 5 periodSeconds: 5完整的微服务架构示例架构图┌─────────────────────────────────────────────────────────────┐ │ Load Balancer │ └───────────────────────────┬─────────────────────────────────┘ │ ┌───────────────┼───────────────┐ ▼ ▼ ▼ ┌───────────┐ ┌───────────┐ ┌───────────┐ │ API GW │ │ API GW │ │ API GW │ └─────┬─────┘ └─────┬─────┘ └─────┬─────┘ │ │ │ ┌─────┴─────────────────┴─────────────────┴─────┐ │ │ ┌───▼───┐ ┌───────┐ ┌─────────┐ ┌─────────┐ │ User │ │ Order │ │ Product │ │ Payment │ │Service│ │Service│ │ Service │ │ Service │ └───┬───┘ └───┬───┘ └────┬────┘ └────┬────┘ │ │ │ │ ▼ ▼ ▼ ▼ ┌─────────────────────────────────────────────────┐ │ PostgreSQL Cluster │ └─────────────────────────────────────────────────┘服务间通信// 使用gRPC进行服务间通信 const grpc require(grpc/grpc-js); const protoLoader require(grpc/proto-loader); const packageDefinition protoLoader.loadSync(order.proto); const orderProto grpc.loadPackageDefinition(packageDefinition); const client new orderProto.OrderService( order-service:50051, grpc.credentials.createInsecure() ); client.createOrder({ userId: 123, items: [item1] }, (error, response) { if (!error) { console.log(Order created:, response); } });CI/CD集成# .github/workflows/deploy.yml name: Deploy to Kubernetes on: push: branches: - main jobs: build: runs-on: ubuntu-latest steps: - uses: actions/checkoutv3 - name: Build Docker image run: | docker build -t ${{ secrets.DOCKER_REGISTRY }}/my-app:${{ github.sha }} . - name: Push Docker image run: | echo ${{ secrets.DOCKER_PASSWORD }} | docker login ${{ secrets.DOCKER_REGISTRY }} -u ${{ secrets.DOCKER_USERNAME }} --password-stdin docker push ${{ secrets.DOCKER_REGISTRY }}/my-app:${{ github.sha }} - name: Deploy to Kubernetes run: | kubectl set image deployment/web-deployment web${{ secrets.DOCKER_REGISTRY }}/my-app:${{ github.sha }}总结微服务架构配合Docker和Kubernetes可以构建出高度可扩展、高可用的应用系统。虽然学习曲线比较陡峭但一旦掌握就能体会到它带来的巨大优势。我的鬃狮蜥Hash对微服务也有自己的理解——它把晒太阳、吃饭、睡觉分成了三个独立的服务每个服务都能独立运行互不影响。这也许就是微服务的精髓吧如果你对微服务或Kubernetes有任何问题欢迎留言交流我是欧阳瑞极客之路永无止境技术栈Docker · Kubernetes · Docker Compose · Minikube · gRPC