build.yaml

name: Build
on:
  push:
    branches:
      - main
  pull_request:
  schedule:
    # every day 1pm (UTC)
    - cron: '0 13 * * *'
  workflow_dispatch:
    description: "Allows manual trigger via GitHub"

jobs:
  build:
    name: Build Job
    runs-on: ubuntu-20.04
    steps:
      - name: Check out code
        uses: actions/checkout@v3

      - name: Docker Build Cache
        id: cache
        uses: actions/cache@v3
        with:
          path: /tmp/docker-builds
          key: ${{ runner.os }}-${{ hashFiles('**/docker/build.sh') }}-${{ hashFiles('**/docker/liberica-base/Dockerfile') }}-${{ hashFiles('**/docker/liberica-jre/Dockerfile') }}-${{ hashFiles('**/.github/workflows/build.yaml') }}-${{ hashFiles('**/.github/.cache_invalidator') }}

      - name: Log into registry
        run: echo "${{ secrets.GITHUB_TOKEN }}" | docker login ghcr.io -u ${{ github.actor }} --password-stdin

      - name: Build docker images
        run: |
          mkdir -p /tmp/docker-builds
          mkdir .tmp
          cp -r /tmp/docker-builds .tmp/docker-builds.pre

          if [[ "${{ github.ref }}" == "refs/heads/main" ]]; then
            echo "Building and pushing Docker images"
            docker/build.sh push
          else
            echo "Building Docker images"
            docker/build.sh
          fi

          cp -r /tmp/docker-builds .tmp/docker-builds.post

      - name: Update cache invalidator
        if: ${{ hashFiles('**/.tmp/docker-builds.pre/*') != hashFiles('**/.tmp/docker-builds.post/*') && steps.cache.outputs.cache-hit == 'true'}}
        run: |
          dd if=/dev/urandom of=.github/.cache_invalidator bs=1K count=1

          echo "[user]
            name = GitHub Actions
            email = ci@permutive.com" >> "${HOME}/.gitconfig"

          git fetch origin
          git checkout ${{ github.head_ref || github.ref_name }}
          git add .github/.cache_invalidator
          git commit -m "Update cache invalidator"
          git push