github-actions-expert（GitHub actions expert 前端）

GitHub Actions Expert

Skill para configurar GitHub Actions con detección proactiva de repos sin CI.

Proactive Detection

Al iniciar trabajo en un proyecto, verificar si existe .github/workflows/:

ls -la .github/workflows/ 2>/dev/null || echo "NO_WORKFLOWS"

Si no hay workflows → preguntar al usuario si quiere agregar CI básico.

Workflow

Phase 0: Knowledge Update

Before generating any workflow, fetch latest documentation:

1. Search for latest GitHub Actions docs via Context7 or WebSearch:

- Current action versions (checkout, setup-node, setup-python, setup-go) - Latest Node.js LTS version - Recent best practices updates

1. Version Reference (verify these are current): Action Current Version actions/checkout v4 actions/setup-node v4 actions/setup-python v5 actions/setup-go v5 actions/cache v4 actions/upload-pages-artifact v3 actions/deploy-pages v4
2. Node.js LTS: Verify current LTS version (use WebSearch if unsure)

Phase 1: Stack Detection

Detect project type and tools:

# Detect project type
ls package.json 2>/dev/null && echo "NODE_PROJECT"
ls pyproject.toml requirements.txt 2>/dev/null && echo "PYTHON_PROJECT"
ls go.mod 2>/dev/null && echo "GO_PROJECT"

# For Node.js - detect package manager
ls pnpm-lock.yaml 2>/dev/null && echo "PNPM"
ls bun.lockb 2>/dev/null && echo "BUN"
ls package-lock.json 2>/dev/null && echo "NPM"

# Detect Node version
cat .nvmrc 2>/dev/null || cat package.json | grep -A2 '"engines"'

Phase 2: Script Analysis (Node.js)

Read package.json using Read tool and detect available scripts.

Look for the scripts section and identify which scripts exist.

Common scripts to check:

• lint → Include linting step
• typecheck → Include type checking
• test → Include testing
• build → Include build step
• test:coverage → Include coverage upload

Phase 3: Workflow Selection

Present options based on detected stack:

For Node.js:

• CI Básico (lint, typecheck, test, build)
• Deploy a GitHub Pages
• Release con Tags (v*)
• Security Scans
• Coverage Upload (Codecov)

For Python:

• CI Básico (ruff, pyright/mypy, pytest)
• Coverage Upload

For Go:

• CI Básico (go vet, golangci-lint, go test)
• Release binaries

Phase 4: Generate Workflows

Load templates from references/ and customize:

1. Replace placeholders:

- {{NODE_VERSION}} → Detected or default (22.x) - {{PACKAGE_MANAGER}} → npm/pnpm/bun - {{INSTALL_COMMAND}} → npm ci / pnpm install --frozen-lockfile / bun install - {{BRANCH}} → main/master (auto-detect) - {{SCRIPTS}} → Based on available scripts

1. Always include:

- Concurrency control - Caching for dependencies - fail-fast strategy

1. Create .github/workflows/ if needed: mkdir -p.github/workflows

Phase 5: Improve Existing Workflows

If workflows exist, analyze for anti-patterns:

cat .github/workflows/*.yml

Anti-patterns to detect:

See references/anti-patterns.md for full guide.

Phase 6: Verification

After generating:

1. Validate YAML (if actionlint available): which actionlint && actionlint.github/workflows/*.yml
2. Check required permissions:

- GitHub Pages → pages: write, id-token: write - Releases → contents: write - PRs → pull-requests: write

1. Show summary: Workflows Created/Updated ========================= ✓.github/workflows/ci.yml - Triggers: push (main), pull_request - Jobs: lint, typecheck, test, build - Node: 22.x with npm Next Steps: 1. Review generated workflows 2. git add.github/workflows/ 3. git commit -m "ci: add GitHub Actions workflow" 4. Push to trigger first run

Templates Reference

Templates are in references/ directory:

Best Practices Enforced

1. Always use latest action versions (@v4 for most)
2. Use npm ci over npm install for reproducible builds
3. Enable caching in setup-node/setup-python/setup-go
4. Add concurrency control to cancel outdated runs
5. Use fail-fast: true to cancel parallel jobs on failure
6. Specify permissions explicitly when needed
7. Use Node 22.x (current LTS)

Concurrency Control Template

Always include in workflows:

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: ${{ github.ref != 'refs/heads/main' }}

This cancels outdated PR runs but never cancels main branch runs.

Package Manager Detection

Branch Detection

# Detect default branch
git symbolic-ref refs/remotes/origin/HEAD 2>/dev/null | sed 's@^refs/remotes/origin/@@'
# Or fallback
git branch -r | grep -E 'origin/(main|master)' | head -1 | sed 's@origin/@@'