CI/CD 파이프라인 구축

name: NestJS quality gate and deploy

on:
  pull_request:
    branches: [main]
  push:
    branches: [main]

env:
  NODE_VERSION: '24'
  IMAGE_NAME: nestjs-app

permissions:
  contents: read

jobs:
  verify:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v7
        with:
          persist-credentials: false

      - name: Set up Node.js
        uses: actions/setup-node@v6
        with:
          node-version: ${{ env.NODE_VERSION }}
          cache: npm

      - name: Install locked dependencies
        run: npm ci

      - name: Lint without rewriting source
        run: npm run lint -- --no-fix

      - name: Test
        run: npm run test -- --runInBand

      - name: Build NestJS
        run: npm run build

  image:
    needs: verify
    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
    runs-on: ubuntu-latest
    outputs:
      repository: ${{ steps.image-meta.outputs.repository }}
      digest: ${{ steps.image-build.outputs.digest }}
    steps:
      - name: Checkout repository
        uses: actions/checkout@v7
        with:
          persist-credentials: false

      - name: Define image repository
        id: image-meta
        env:
          DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
        run: echo "repository=docker.io/${DOCKER_USERNAME}/${IMAGE_NAME}" >> "$GITHUB_OUTPUT"

      - name: Log in to Docker Hub
        uses: docker/login-action@v4
        with:
          registry: docker.io
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

      - name: Build and push once
        id: image-build
        uses: docker/build-push-action@v7
        with:
          context: .
          push: true
          tags: ${{ steps.image-meta.outputs.repository }}:${{ github.sha }}
          cache-from: type=gha
          cache-to: type=gha,mode=max

  deploy:
    needs: image
    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
    runs-on: ubuntu-latest
    timeout-minutes: 10
    environment:
      name: production
    concurrency:
      group: production
      cancel-in-progress: false
    steps:
      - name: Deploy exact digest and run bounded health gate
        env:
          EC2_HOST: ${{ secrets.EC2_HOST }}
          EC2_USERNAME: ${{ secrets.EC2_USERNAME }}
          EC2_SSH_KEY: ${{ secrets.EC2_SSH_KEY }}
          EC2_SSH_KNOWN_HOSTS: ${{ secrets.EC2_SSH_KNOWN_HOSTS }}
          IMAGE_REF: ${{ needs.image.outputs.repository }}@${{ needs.image.outputs.digest }}
        run: |
          install -d -m 700 "$HOME/.ssh"
          printf '%s\n' "$EC2_SSH_KEY" > "$HOME/.ssh/id_ed25519"
          chmod 600 "$HOME/.ssh/id_ed25519"
          printf '%s\n' "$EC2_SSH_KNOWN_HOSTS" > "$HOME/.ssh/known_hosts"
          chmod 600 "$HOME/.ssh/known_hosts"

          ssh \
            -i "$HOME/.ssh/id_ed25519" \
            -o BatchMode=yes \
            -o StrictHostKeyChecking=yes \
            -o ConnectTimeout=10 \
            -o ServerAliveInterval=15 \
            -o ServerAliveCountMax=2 \
            "${EC2_USERNAME}@${EC2_HOST}" \
            bash -s -- "$IMAGE_REF" <<'REMOTE'
          set -euo pipefail

          IMAGE_REF="$1"
          cd /opt/nestjs-app

          sudo env IMAGE="$IMAGE_REF" docker compose pull app
          sudo env IMAGE="$IMAGE_REF" docker compose up -d --no-deps app

          healthy=false
          for attempt in $(seq 1 12); do
            if curl --fail --silent --show-error --max-time 2 \
              http://127.0.0.1:3000/health > /dev/null; then
              healthy=true
              break
            fi
            sleep 5
          done

          if [ "$healthy" != "true" ]; then
            echo "Health gate failed; release is not accepted."
            echo "Rollback is explicit: redeploy a previously approved digest."
            exit 1
          fi
          REMOTE