caching-strategy-optimizer

缓存策略优化器

借助智能缓存，大幅加快 CI 流水线。

缓存键策略

包管理器缓存

# NPM - Hash package-lock.json
- uses: actions/cache@v3
  with:
    path: ~/.npm
    key: ${{ runner.os }}-npm-${{ hashFiles('**/package-lock.json') }}
    restore-keys: |
      ${{ runner.os }}-npm-

# pnpm - More aggressive caching
- uses: pnpm/action-setup@v2
  with:
    version: 8

- uses: actions/cache@v3
  with:
    path: |
      ~/.pnpm-store
      node_modules
    key: ${{ runner.os }}-pnpm-${{ hashFiles('**/pnpm-lock.yaml') }}
    restore-keys: |
      ${{ runner.os }}-pnpm-

# Python pip
- uses: actions/cache@v3
  with:
    path: ~/.cache/pip
    key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}

# Cargo/Rust
- uses: actions/cache@v3
  with:
    path: |
      ~/.cargo/bin/
      ~/.cargo/registry/index/
      ~/.cargo/registry/cache/
      ~/.cargo/git/db/
      target/
    key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}

Docker 层缓存

使用 Buildx

- name: Set up Docker Buildx
  uses: docker/setup-buildx-action@v3

- name: Build with cache
  uses: docker/build-push-action@v5
  with:
    context: .
    cache-from: type=gha
    cache-to: type=gha,mode=max

基于 Registry 的缓存

- name: Build with registry cache
  uses: docker/build-push-action@v5
  with:
    context: .
    cache-from: type=registry,ref=myapp:buildcache
    cache-to: type=registry,ref=myapp:buildcache,mode=max

构建输出缓存

# Next.js cache
- uses: actions/cache@v3
  with:
    path: |
      ${{ github.workspace }}/.next/cache
    key: ${{ runner.os }}-nextjs-${{ hashFiles('**/package-lock.json') }}-${{ hashFiles('**/*.js', '**/*.jsx', '**/*.ts', '**/*.tsx') }}
    restore-keys: |
      ${{ runner.os }}-nextjs-${{ hashFiles('**/package-lock.json') }}-
      ${{ runner.os }}-nextjs-

# Webpack cache
- uses: actions/cache@v3
  with:
    path: node_modules/.cache/webpack
    key: ${{ runner.os }}-webpack-${{ hashFiles('webpack.config.js') }}-${{ hashFiles('src/**') }}

# TypeScript build cache
- uses: actions/cache@v3
  with:
    path: |
      dist
      tsconfig.tsbuildinfo
    key: ${{ runner.os }}-tsc-${{ hashFiles('**/*.ts') }}

测试结果缓存

# Jest cache
- uses: actions/cache@v3
  with:
    path: /tmp/jest_rt
    key: ${{ runner.os }}-jest-${{ hashFiles('**/*.test.ts') }}

# Pytest cache
- uses: actions/cache@v3
  with:
    path: .pytest_cache
    key: ${{ runner.os }}-pytest-${{ hashFiles('**/*test*.py') }}

优化前后指标

## Before Optimization

- Total time: 12 minutes
- npm ci: 4 minutes
- Build: 5 minutes
- Tests: 3 minutes

## After Caching

- Total time: 3 minutes
- npm ci: 30 seconds (cache hit)
- Build: 1 minute (incremental)
- Tests: 1.5 minutes (cache hit)

**Improvement: 75% faster (12m → 3m)**

缓存命中率监控

- name: Check cache hit
  id: cache
  uses: actions/cache@v3
  with:
    path: node_modules
    key: ${{ runner.os }}-deps-${{ hashFiles('package-lock.json') }}

- name: Log cache status
  run: |
    if [ "${{ steps.cache.outputs.cache-hit }}" == "true" ]; then
      echo "✅ Cache hit - saved $(date -u -d @$SECONDS +%M:%S)"
    else
      echo "❌ Cache miss - installing from scratch"
    fi

最佳实践

1. 精确的键：将所有依赖项纳入哈希
2. 恢复键：回退到部分匹配
3. 多个路径：将相关文件一起缓存
4. 大小限制：GitHub Actions 的限制为 10GB
5. 过期时间：缓存会在 7 天后过期
6. Mode=max：使用 Docker 缓存模式以获得更高的命中率
7. 监控命中情况：跟踪缓存效果

常见陷阱

❌ 键过于宽泛：key: deps（始终命中） ✅ 指定具体键：key: deps-${{ hashFiles('package-lock.json') }}

❌ 缺少 restore-keys：轻微变更也会导致缓存未命中 ✅ 恢复键：提供部分匹配回退

❌ 使用错误的锁文件缓存 node_modules ✅ 匹配锁文件：对正确的锁文件计算哈希

输出检查清单

• 已配置包管理器缓存
• 已配置构建输出缓存
• 已配置 Docker 层缓存（如适用）
• 已配置测试缓存
• 缓存键使用文件哈希
• 已设置用于回退的恢复键
• 已记录优化前后指标
• 已监控缓存命中情况