部署到 Kubernetes

本节学习如何将 CI/CD 流水线与 Kubernetes 集成，实现自动化部署。

前置知识

💡 阅读本章前，请确保已完成：
GitHub Actions - 掌握 CI/CD 工作流配置
Deployment 详解 - 理解 Deployment 概念

部署方式概览

方式	工具	特点
推送式	kubectl, Helm	简单直接，适合入门
GitOps	ArgoCD, Flux	声明式，可追溯，生产推荐

本教程使用 kubectl 推送式 部署，适合学习和小型项目。

Kubernetes 清单文件

目录结构

k8s/
├── base/
│   ├── deployment.yaml
│   ├── service.yaml
│   └── kustomization.yaml
└── overlays/
    ├── staging/
    │   └── kustomization.yaml
    └── production/
        └── kustomization.yaml

Deployment 配置

yaml

# k8s/base/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
  labels:
    app: myapp
spec:
  replicas: 3
  selector:
    matchLabels:
      app: myapp
  template:
    metadata:
      labels:
        app: myapp
    spec:
      containers:
      - name: myapp
        image: username/myapp:latest    # 镜像会被 CI/CD 更新
        ports:
        - containerPort: 3000
        resources:
          requests:
            cpu: 100m
            memory: 128Mi
          limits:
            cpu: 500m
            memory: 512Mi
        livenessProbe:
          httpGet:
            path: /health
            port: 3000
          initialDelaySeconds: 10
          periodSeconds: 10
        readinessProbe:
          httpGet:
            path: /ready
            port: 3000
          initialDelaySeconds: 5
          periodSeconds: 5

Service 配置

yaml

# k8s/base/service.yaml
apiVersion: v1
kind: Service
metadata:
  name: myapp
spec:
  selector:
    app: myapp
  ports:
  - port: 80
    targetPort: 3000
  type: ClusterIP

配置 kubectl 访问

方式 1：使用 kubeconfig

yaml

# GitHub Actions 中配置
steps:
  - name: Configure kubectl
    run: |
      mkdir -p ~/.kube
      echo "${{ secrets.KUBE_CONFIG }}" | base64 -d > ~/.kube/config

生成 KUBE_CONFIG Secret：

bash

# 将 kubeconfig 编码为 base64
cat ~/.kube/config | base64 -w 0

方式 2：使用云服务商 Action

yaml

# Azure AKS
- uses: azure/aks-set-context@v3
  with:
    resource-group: myResourceGroup
    cluster-name: myAKSCluster

# AWS EKS
- uses: aws-actions/configure-aws-credentials@v4
  with:
    aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
    aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
    aws-region: us-east-1

- run: aws eks update-kubeconfig --name my-cluster

# GCP GKE
- uses: google-github-actions/get-gke-credentials@v2
  with:
    cluster_name: my-cluster
    location: us-central1

部署策略

1. 直接更新镜像

最简单的方式，适合开发环境：

yaml

- name: Deploy
  run: |
    kubectl set image deployment/myapp \
      myapp=username/myapp:${{ github.sha }}

2. 应用完整清单

yaml

- name: Deploy
  run: |
    # 替换镜像标签
    sed -i "s|image:.*|image: username/myapp:${{ github.sha }}|" k8s/deployment.yaml

    # 应用配置
    kubectl apply -f k8s/

3. 使用 Kustomize

yaml

# k8s/base/kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization

resources:
  - deployment.yaml
  - service.yaml

yaml

# k8s/overlays/production/kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization

resources:
  - ../../base

images:
  - name: username/myapp
    newTag: latest    # 会被 CI/CD 替换

replicas:
  - name: myapp
    count: 5

yaml

# GitHub Actions
- name: Deploy with Kustomize
  run: |
    cd k8s/overlays/production
    kustomize edit set image username/myapp=username/myapp:${{ github.sha }}
    kubectl apply -k .

部署验证

等待 Rollout 完成

yaml

- name: Wait for deployment
  run: |
    kubectl rollout status deployment/myapp --timeout=300s

验证部署健康

yaml

- name: Verify deployment
  run: |
    # 检查 Pod 状态
    kubectl get pods -l app=myapp

    # 检查 Pod 是否 Ready
    kubectl wait --for=condition=ready pod -l app=myapp --timeout=120s

    # 检查副本数
    READY=$(kubectl get deployment myapp -o jsonpath='{.status.readyReplicas}')
    DESIRED=$(kubectl get deployment myapp -o jsonpath='{.spec.replicas}')

    if [ "$READY" != "$DESIRED" ]; then
      echo "Deployment not healthy: $READY/$DESIRED ready"
      exit 1
    fi

运行冒烟测试

yaml

- name: Smoke test
  run: |
    # 端口转发
    kubectl port-forward svc/myapp 8080:80 &
    sleep 5

    # 健康检查
    curl -f http://localhost:8080/health || exit 1

    # 清理
    pkill -f "port-forward"

回滚机制

自动回滚

yaml

- name: Deploy with auto-rollback
  run: |
    # 记录当前版本
    CURRENT_IMAGE=$(kubectl get deployment myapp -o jsonpath='{.spec.template.spec.containers[0].image}')

    # 更新镜像
    kubectl set image deployment/myapp myapp=username/myapp:${{ github.sha }}

    # 等待 rollout，失败则回滚
    if ! kubectl rollout status deployment/myapp --timeout=300s; then
      echo "Deployment failed, rolling back..."
      kubectl rollout undo deployment/myapp
      exit 1
    fi

部署流程图

完整部署工作流

yaml

# .github/workflows/deploy.yml
name: Deploy to Kubernetes

on:
  push:
    branches: [main]

env:
  REGISTRY: docker.io
  IMAGE_NAME: myapp

jobs:
  build:
    runs-on: ubuntu-latest
    outputs:
      image-tag: ${{ steps.meta.outputs.tags }}

    steps:
    - uses: actions/checkout@v4

    - uses: docker/setup-buildx-action@v3

    - uses: docker/login-action@v3
      with:
        username: ${{ secrets.DOCKERHUB_USERNAME }}
        password: ${{ secrets.DOCKERHUB_TOKEN }}

    - id: meta
      uses: docker/metadata-action@v5
      with:
        images: ${{ env.REGISTRY }}/${{ secrets.DOCKERHUB_USERNAME }}/${{ env.IMAGE_NAME }}
        tags: type=sha

    - uses: docker/build-push-action@v5
      with:
        context: .
        push: true
        tags: ${{ steps.meta.outputs.tags }}
        cache-from: type=gha
        cache-to: type=gha,mode=max

  deploy:
    needs: build
    runs-on: ubuntu-latest
    environment: production

    steps:
    - uses: actions/checkout@v4

    - uses: azure/setup-kubectl@v3

    - name: Configure kubectl
      run: |
        mkdir -p ~/.kube
        echo "${{ secrets.KUBE_CONFIG }}" | base64 -d > ~/.kube/config

    - name: Deploy
      run: |
        kubectl set image deployment/myapp \
          myapp=${{ needs.build.outputs.image-tag }}

    - name: Wait for rollout
      run: |
        kubectl rollout status deployment/myapp --timeout=300s

    - name: Verify deployment
      run: |
        kubectl get pods -l app=myapp
        kubectl wait --for=condition=ready pod -l app=myapp --timeout=120s

    - name: Rollback on failure
      if: failure()
      run: |
        kubectl rollout undo deployment/myapp
        echo "::error::Deployment failed, rolled back to previous version"

环境管理

多环境部署

yaml

jobs:
  deploy-staging:
    runs-on: ubuntu-latest
    environment: staging
    steps:
      - name: Deploy to staging
        run: kubectl apply -k k8s/overlays/staging

  deploy-production:
    needs: deploy-staging
    runs-on: ubuntu-latest
    environment: production
    steps:
      - name: Deploy to production
        run: kubectl apply -k k8s/overlays/production

环境保护规则

在 GitHub 仓库设置中配置：

Settings → Environments → New environment
配置保护规则：
- Required reviewers（需要审批）
- Wait timer（等待时间）
- Deployment branches（限制分支）

部署通知

Slack 通知

yaml

- name: Notify Slack
  if: always()
  uses: 8398a7/action-slack@v3
  with:
    status: ${{ job.status }}
    fields: repo,message,commit,author,action,eventName,ref,workflow
  env:
    SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK }}

部署状态徽章

在 README.md 中添加：

markdown

![Deploy](https://github.com/username/repo/actions/workflows/deploy.yml/badge.svg)

实战练习

完整示例项目结构

myapp/
├── .github/
│   └── workflows/
│       └── ci-cd.yml
├── k8s/
│   ├── deployment.yaml
│   └── service.yaml
├── src/
│   └── index.js
├── Dockerfile
├── package.json
└── README.md

部署清单

yaml

# k8s/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
spec:
  replicas: 2
  selector:
    matchLabels:
      app: myapp
  template:
    metadata:
      labels:
        app: myapp
    spec:
      containers:
      - name: myapp
        image: username/myapp:latest
        ports:
        - containerPort: 3000
        env:
        - name: NODE_ENV
          value: production
---
apiVersion: v1
kind: Service
metadata:
  name: myapp
spec:
  selector:
    app: myapp
  ports:
  - port: 80
    targetPort: 3000
  type: LoadBalancer

本地测试部署

bash

# 1. 构建镜像
docker build -t myapp:test .

# 2. 加载到 Minikube
minikube image load myapp:test

# 3. 更新清单中的镜像
sed -i 's|username/myapp:latest|myapp:test|' k8s/deployment.yaml

# 4. 部署
kubectl apply -f k8s/

# 5. 验证
kubectl get pods
kubectl get svc

# 6. 访问应用（Minikube）
minikube service myapp

小结

kubectl 是最简单的部署方式，适合学习
配置 kubeconfig 或使用云服务商 Action 连接集群
使用 rollout status 等待部署完成
实现 自动回滚 保证部署安全
环境保护 确保生产部署可控
添加通知及时了解部署状态

下一步

恭喜你完成了 CI/CD 章节！现在你已经掌握了从代码到部署的完整流程。

建议接下来：

在实际项目中实践 CI/CD 流水线
探索 GitOps 工具（ArgoCD、Flux）
学习 Kubernetes 监控和日志

返回 Kubernetes 教程首页

部署到 Kubernetes ​

前置知识 ​

部署方式概览 ​

Kubernetes 清单文件 ​

目录结构 ​

Deployment 配置 ​

Service 配置 ​

配置 kubectl 访问 ​

方式 1：使用 kubeconfig ​

方式 2：使用云服务商 Action ​

部署策略 ​

1. 直接更新镜像 ​

2. 应用完整清单 ​

3. 使用 Kustomize ​

部署验证 ​

等待 Rollout 完成 ​

验证部署健康 ​

运行冒烟测试 ​

回滚机制 ​

自动回滚 ​

部署流程图 ​

完整部署工作流 ​

环境管理 ​

多环境部署 ​

环境保护规则 ​

部署通知 ​

Slack 通知 ​

部署状态徽章 ​

实战练习 ​

完整示例项目结构 ​

部署清单 ​

本地测试部署 ​

小结 ​

下一步 ​

部署到 Kubernetes

前置知识

部署方式概览

Kubernetes 清单文件

目录结构

Deployment 配置

Service 配置

配置 kubectl 访问

方式 1：使用 kubeconfig

方式 2：使用云服务商 Action

部署策略

1. 直接更新镜像

2. 应用完整清单

3. 使用 Kustomize

部署验证

等待 Rollout 完成

验证部署健康

运行冒烟测试

回滚机制

自动回滚

部署流程图

完整部署工作流

环境管理

多环境部署

环境保护规则

部署通知

Slack 通知

部署状态徽章

实战练习

完整示例项目结构

部署清单

本地测试部署

小结

下一步