docker-push.yml

name: "Docker Push"

on:
  release:
    types: [published]
  workflow_dispatch:
    inputs:
      force_rebuild:
        description: 'Force container rebuild'
        required: true
        type: choice
        options: [yes, no]
  schedule:
    - cron: '30 12 * * *'

permissions:
  packages: write
  contents: read

env:
  IMAGE_NAME: ${{ github.repository }}

jobs:
  Docker:
    name: Docker Build & Publish
    runs-on: ubuntu-latest

    env:
      DOCKER_FILE: alpine

    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Login to DockerHub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

      - name: Login to GitHub Container Registry
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Checkout the latest tag
        run: |
          rev=$(git rev-list --tags --max-count=1)
          tag=$(git describe --tags "$rev")

          if [[ -z "$tag" ]] ; then
            echo "::error::Can't find the latest tag"
            exit 1
          fi

          echo -e "\033[34mRev:\033[0m $rev"
          echo -e "\033[34mTag:\033[0m $tag"

          git checkout "$tag"

      - name: Prepare metadata for build
        id: metadata
        run: |
          rev=$(git rev-list --tags --max-count=1)
          version=$(git describe --tags "$rev" | tr -d 'v')

          if [[ -z "$version" ]] ; then
            echo "::error::Can't find version info"
            exit 1
          fi

          docker_file=".docker/${{env.DOCKER_FILE}}.docker"
          base_image=$(grep 'FROM ' $docker_file | grep -v 'builder' | sed 's#${REGISTRY}/##' | tail -1 | cut -f2 -d' ')

          if [[ -z "$base_image" ]] ; then
            echo "::error::Can't extract base image info"
            exit 1
          fi

          echo "version=$version" >> $GITHUB_OUTPUT
          echo "dockerfile=$docker_file" >> $GITHUB_OUTPUT
          echo "baseimage=$base_image" >> $GITHUB_OUTPUT

          echo -e "\033[34mVersion:\033[0m    $version"
          echo -e "\033[34mDockerfile:\033[0m $docker_file"
          echo -e "\033[34mBase image:\033[0m $base_image"

      - name: Check if build/rebuild is required
        id: build_check
        run: |
          if [[ "${{github.event_name}}" == "release" ]] ; then
            echo "build=true" >> $GITHUB_OUTPUT
            exit 0
          fi

          if [[ "${{ github.event.inputs.force_rebuild }}" == "true" ]] ; then
            echo "::warning::Rebuild is required (reason: forced rebuild)"
            echo "build=true" >> $GITHUB_OUTPUT
            exit 0
          fi

          echo -e "::group::\033[34mDownloading built image…\033[0m"

          if ! docker pull ghcr.io/${{env.IMAGE_NAME}}:latest ; then
            echo "::error::Can't download image ghcr.io/${{env.IMAGE_NAME}}:latest"
            exit 1
          fi

          echo "::endgroup::"
          echo -e "::group::\033[34mDownloading base image…\033[0m"

          if ! docker pull ${{steps.metadata.outputs.baseimage}} ; then
            echo "::error::Can't download image ${{steps.metadata.outputs.baseimage}}"
            exit 1
          fi

          echo "::endgroup::"

          base_layer=$(docker inspect "${{steps.metadata.outputs.baseimage}}" | jq -r '.[0].RootFS.Layers[-1]')

          if [[ -z "$base_layer" ]] ; then
            echo "::error::Can't extract layers info from base image"
            exit 1
          fi

          if ! docker inspect "ghcr.io/${{env.IMAGE_NAME}}:latest" | jq -r '.[0].RootFS.Layers' | grep -q "$base_layer" ; then
            echo "::warning::Rebuild image (reason: base image rebuilt)"
            echo "build=true" >> $GITHUB_OUTPUT
            exit 0
          fi

      - name: Build and push Docker images (Docker)
        if: ${{ steps.build_check.outputs.build == 'true' }}
        uses: docker/build-push-action@v5
        with:
          push: true
          context: .
          file: ${{steps.metadata.outputs.dockerfile}}
          build-args: |
            REGISTRY=docker.io
          tags: |
            ${{env.IMAGE_NAME}}:${{steps.metadata.outputs.version}}
            ${{env.IMAGE_NAME}}:latest

      - name: Build and push Docker images (GHCR)
        if: ${{ steps.build_check.outputs.build == 'true' }}
        uses: docker/build-push-action@v5
        with:
          push: true
          context: .
          file: ${{steps.metadata.outputs.dockerfile}}
          build-args: |
            REGISTRY=ghcr.io
          tags: |
            ghcr.io/${{env.IMAGE_NAME}}:${{steps.metadata.outputs.version}}
            ghcr.io/${{env.IMAGE_NAME}}:latest

      - name: Show info about built Docker image
        if: ${{ steps.build_check.outputs.build == 'true' }}
        uses: essentialkaos/docker-info-action@v1
        with:
          image: ghcr.io/${{env.IMAGE_NAME}}:latest
          show-labels: true