📘 第21课：测试环境

Docker Compose

🧪 用Compose搭建测试环境

自动化测试需要隔离、可复现、可并行的环境。Compose让测试环境的搭建和销毁变得快速且一致。

📝 测试环境配置

# docker-compose.test.yml ✅
services:
  sut:    # System Under Test
    build:
      context: .
      target: test
    environment:
      - NODE_ENV=test
      - DB_URL=postgres://test:test@db:5432/myapp_test
      - REDIS_URL=redis://redis:6379/1
    depends_on:
      db:
        condition: service_healthy
      redis:
        condition: service_started
    command: npm test

  db:
    image: postgres:16-alpine
    environment:
      POSTGRES_USER: test
      POSTGRES_PASSWORD: test
      POSTGRES_DB: myapp_test
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U test"]
      interval: 2s
      timeout: 2s
      retries: 10

  redis:
    image: redis:7-alpine

# 运行测试 ✅
docker compose -f docker-compose.test.yml up --abort-on-container-exit --exit-code-from sut

🔄 CI/CD集成

# GitHub Actions集成 ✅
name: Test
on: [push, pull_request]
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: Run tests
        run: |
          docker compose -f docker-compose.test.yml up --abort-on-container-exit
          docker compose -f docker-compose.test.yml down -v

# GitLab CI集成
test:
  stage: test
  script:
    - docker compose -f docker-compose.test.yml up --abort-on-container-exit --exit-code-from sut
    - docker compose -f docker-compose.test.yml down -v
  after_script:
    - docker compose -f docker-compose.test.yml down -v

📊 测试类型与策略

# 单元测试——不需要数据库等外部依赖
services:
  unit-test:
    build: .
    command: npm run test:unit

# 集成测试——需要真实外部服务 ✅
services:
  integration-test:
    build: .
    depends_on:
      db:
        condition: service_healthy
    command: npm run test:integration

# E2E测试——需要完整环境
services:
  e2e:
    build:
      context: ./e2e
    depends_on:
      - app
    command: npx playwright test

# 性能测试
services:
  k6:
    image: grafana/k6
    volumes:
      - ./tests/perf:/scripts
    command: run /scripts/load-test.js

🧹 测试数据管理

# 初始化测试数据 ✅
services:
  db:
    image: postgres:16-alpine
    volumes:
      - ./tests/fixtures:/docker-entrypoint-initdb.d  # 自动执行SQL

# 测试前重置数据
services:
  db:
    image: postgres:16-alpine
    tmpfs:
      - /var/lib/postgresql/data   # 使用内存，每次干净

❓ 常见问题

📚 深度补充：测试环境进阶要点

【Compose编排阶段】生产环境注意事项

常见误区与避坑指南

1. 过度配置：不是所有服务都需要高可用，根据实际需求选择架构复杂度，避免过度工程
2. 忽略日志：日志是排障的关键，确保日志格式统一、级别合理、采集完整
3. 资源超卖：容器资源限制不是摆设，超卖会导致性能下降甚至OOM Kill
4. 安全忽视：默认配置不等于安全配置，生产环境必须加固（非root、只读FS、最小能力）
5. 监控缺失：没有监控等于盲飞，至少要有基础的健康检查和资源监控
6. 手动运维：能自动化的绝不手动，手动操作容易出错且不可追溯
7. 忽略网络策略：默认所有容器互通不安全，应按最小权限原则配置网络

进阶阅读与参考

• Docker官方文档：https://docs.docker.com/
• Docker最佳实践指南：Dev Best Practices
• CIS Docker Benchmark：容器安全基线检查标准
• 12-Factor App方法论：https://12factor.net/
• Google SRE Book：运维可靠性工程实践
• Kubernetes官方文档：https://kubernetes.io/docs/

Docker命令速查卡

# 容器生命周期
docker create/start/stop/restart/rm/pause/unpause
docker logs/top/stats/inspect/exec diff

# 镜像构建
docker build/pull/push/tag/rmi/images/history
docker save/load/import/manifest

# 网络与存储
docker network create/ls/inspect/connect/disconnect/rm/prune
docker volume create/ls/inspect/rm/prune

# Docker Compose
docker compose up/down/ps/logs/build/exec
docker compose config/stop/start/scale/top/cp

# 系统维护
docker system df/prune/info
docker builder prune
docker container/prune/image prune

# K8s常用命令
kubectl get/describe/logs/exec/apply/delete
kubectl rollout status/undo/history
kubectl scale/autoscale/set

本阶段知识脉络

Compose文件完整结构

version: "3.8"            # Compose文件版本

services:                  # 服务定义（必填）
  web:
    image: nginx:alpine    # 或 build: .
    ports:
      - "8080:80"
    environment:
      - KEY=VALUE
    volumes:
      - ./html:/usr/share/nginx/html:ro
    networks:
      - frontend
    depends_on:
      - api
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost/"]
      interval: 30s
    deploy:
      replicas: 2
      resources:
        limits:
          cpus: '0.5'
          memory: 256M
    restart: unless-stopped

networks:                  # 网络定义
  frontend:
    driver: bridge

volumes:                   # 卷定义
  db-data:

secrets:                   # 密钥定义
  db_password:
    file: ./db_password.txt

configs:                   # 配置定义
  nginx_config:
    file: ./nginx.conf

Compose项目生命周期

实战案例：故障排查流程

# Step 1: 检查容器状态
docker ps -a                          # 查看所有容器
docker inspect <container>            # 查看详细配置

# Step 2: 查看日志
docker logs --tail 100 <container>    # 最近100行日志
docker logs --since 1h <container>    # 最近1小时

# Step 3: 进入容器排查
docker exec -it <container> sh        # 进入容器shell

# Step 4: 检查资源
docker stats --no-stream              # 资源使用概览
docker system df                      # 磁盘使用

# Step 5: 网络排查
docker network ls                     # 网络列表
docker exec <c> ping <target>        # 网络连通性
docker exec <c> nslookup <svc>       # DNS解析

# Step 6: 检查健康状态
docker inspect --format '{{.State.Health}}' <c>
docker inspect --format '{{.State.ExitCode}}' <c>
docker inspect --format '{{.State.OOMKilled}}' <c>

Dockerfile模板：多语言通用

# 通用最佳实践模板
FROM alpine:3.19 AS builder
# ... 构建步骤 ...

FROM alpine:3.19
RUN addgroup -S appgroup && adduser -S appuser -G appgroup
WORKDIR /app
COPY --from=builder /app/output .
USER appuser
HEALTHCHECK --interval=30s --timeout=3s --retries=3 \
  CMD wget -qO- http://localhost:8080/health || exit 1
EXPOSE 8080
CMD ["./app"]

Docker Compose健康检查模板

services:
  app:
    build: .
    healthcheck:
      test: ["CMD", "wget", "-qO-", "http://localhost:8080/health"]
      interval: 30s
      timeout: 5s
      retries: 3
      start_period: 30s
    restart: unless-stopped
    deploy:
      resources:
        limits:
          cpus: '1'
          memory: 512M

性能调优要点