deploy-single-docker-image.yml

name: Build and push single docker image

on:
  workflow_call:
    inputs:
      image_name:
        description: 'Name of the image to build and push'
        required: true
        type: string
      directory:
        description: 'Directory containing the Dockerfile'
        required: true
        type: string
      docker_file_name:
        description: 'Name of the Dockerfile'
        required: false
        default: 'Dockerfile'
        type: string
      docker_registry:
        description: 'Docker registry to push to'
        required: true
        default: 'ghcr.io'
        type: string
      github_ref_before:
        description: 'Github ref before the change'
        required: true
        type: string
      github_ref_after:
        description: 'Github ref after the change'
        required: true
        type: string
      force_rebuild:
        description: 'Forces rebuild of docker image, even if no changes are detected'
        default: false
        type: boolean
      platforms:
        description: 'Platforms to build for'
        default: |
          linux/amd64
          linux/arm64
          linux/arm/v7
        type: string
      depends_on_paths:
        description: 'Directories that need to be checked for changes before building this image'
        required: false
        type: string
      build_args:
        description: 'Build arguments for the Dockerfile'
        required: false
        type: string
    outputs:
      rebuild:
        description: 'Whether the image is rebuilt or not'
        value: ${{ jobs.check.outputs.rebuild }}
      image_tags:
        description: 'Tags of the deployed image with image name'
        value: ${{ jobs.build-and-push.outputs.image_tags }}
      one_image_tag_short:
        description: 'One tag of the deployed image without image name'
        value: ${{ jobs.build-and-push.outputs.one_image_tag_short }}
      one_image_tag_long:
        description: 'One tag of the deployed image with image name'
        value: ${{ jobs.build-and-push.outputs.one_image_tag_long }}
    secrets:
      SA_GITHUB_PAT:
        description: 'Github PAT with access to the repository'
        required: true
      SA_GITHUB_USERNAME:
        description: 'Github username'
        required: true

jobs:
  check:
    name: Check for changes
    outputs:
      rebuild: ${{ steps.set-outputs.outputs.rebuild }}
    runs-on: ubuntu-24.04
    steps:
    - name: Checkout Dockerfile
      if: ${{ inputs.force_rebuild == false }}
      uses: actions/checkout@v4
      with:
        repository: ${{ github.repository }} 
        path: source
        ref: ${{ inputs.github_ref_after }}
        token: ${{secrets.SA_GITHUB_PAT}}
        fetch-depth: 0
    - name: Validate github_ref_before and github_ref_after
      if: ${{ inputs.force_rebuild == false }}
      id: validate-inputs
      run: |
        echo "Check validity of github_ref_before.."
        if git cat-file -e ${{ inputs.github_ref_before }}^{commit}; then
          echo "github_ref_before='${{ inputs.github_ref_before }}' is a commit!✅"
        else
          echo "github_ref_before='${{ inputs.github_ref_before }}' is not a commit!❌ -> Rebuild image!"
          echo "validation_failed=true" >> $GITHUB_OUTPUT
          exit 0
        fi
        echo "Check validity of github_ref_after.."
        if git cat-file -e ${{ inputs.github_ref_after }}^{commit}; then
          echo "github_ref_after='${{ inputs.github_ref_after }}' is a commit!✅"
        else
          echo "github_ref_after='${{ inputs.github_ref_after }}' is not a commit!❌ -> Rebuild image!"
          echo "validation_failed=true" >> $GITHUB_OUTPUT
          exit 0
        fi
        echo "validation_failed=false" >> $GITHUB_OUTPUT
      working-directory: source
    - name: Parse depends_on_paths
      if: ${{  inputs.force_rebuild == false && steps.validate-inputs.outputs.validation_failed == 'false' }}
      id: setup-regex
      shell: python3 {0}
      working-directory: source
      run: |
        import os
        list_of_paths = """${{ inputs.depends_on_paths }}""".split("\n")
        # remove all empty lines
        list_of_paths = list(filter(None, list_of_paths))
        for path in list_of_paths:
          if os.path.isdir(f"{path}"):
            path = f"{path}/*"
          elif os.path.isfile(f"{path}"):
            path = f"{path}"
          else:
            print(f"Path {path} does not exist!❌")
            exit(1)
        if not "${{ inputs.directory }}" in list_of_paths:
          list_of_paths.append("${{ inputs.directory }}/*")
        regex = "|".join(list_of_paths)
        # set the regex as an output
        with open(os.environ["GITHUB_OUTPUT"], "a") as f:
          f.write(f"regex={regex}\n")
        print(f"Set regex={regex}")
    - name: Get changed files
      if: ${{ inputs.force_rebuild == false && steps.validate-inputs.outputs.validation_failed == 'false' }}
      id: check
      run: |
        echo "Checking for changes in paths ${{ steps.setup-regex.outputs.regex }}.."
        EXIT_CODE=0
        changed_files="$(git diff --name-only ${{ inputs.github_ref_before }} ${{ inputs.github_ref_after }} | grep -E '${{ steps.setup-regex.outputs.regex }}')" || EXIT_CODE=$?
        if [ $EXIT_CODE -eq 1 ]; then
          echo "No changes detected in ${{ steps.setup-regex.outputs.regex }}!🔍"
          echo "changes_detected=false" >> $GITHUB_OUTPUT
          exit 0
        elif [ $EXIT_CODE -ne 0 ]; then
          echo "Error while checking for changes in ${{ steps.setup-regex.outputs.regex }}!❌"
          exit $EXIT_CODE
        else
          echo "🔍 Changes detected with regex ${{ steps.setup-regex.outputs.regex }} in the following files:"
          echo "$changed_files"
          echo "changes_detected=true" >> $GITHUB_OUTPUT
        fi
      working-directory: source
    - name: Set outputs
      if: ${{ inputs.force_rebuild == false }}
      id: set-outputs
      run: |
        echo "rebuild=${{ steps.check.outputs.changes_detected == 'true' || steps.validate-inputs.outputs.validation_failed == 'true' }}" >> $GITHUB_OUTPUT

  build-and-push:
    name: Build and push
    needs: check
    runs-on: ubuntu-24.04
    outputs:
      image_tags: ${{ steps.meta.outputs.tags }}
      one_image_tag_short: ${{ steps.extract-one-tag.outputs.tag_short }}
      one_image_tag_long: ${{ steps.extract-one-tag.outputs.tag_long }}
    steps:
    - name: Checkout Dockerfile
      uses: actions/checkout@v4
      with:
        repository: ${{ github.repository }} 
        path: source
        ref: ${{github.ref}}
        token: ${{secrets.SA_GITHUB_PAT}}
        fetch-depth: 0
    - name: Get context / Path of Dockerfile
      id: get-context
      run: |
        if [ -f source/${{ inputs.directory }}/${{ inputs.docker_file_name }} ]; then
          echo "path=source/${{ inputs.directory }}" >> $GITHUB_OUTPUT
        elif [ -f source/${{ inputs.directory }}/.devcontainer/${{ inputs.docker_file_name }} ]; then
          echo "path=source/${{ inputs.directory }}/.devcontainer" >> $GITHUB_OUTPUT
        else
          echo "No Dockerfile found for image ${{ inputs.image_name }} in dokcer_directory ${{ inputs.directory }} with docker_file_name ${{ inputs.docker_file_name }}!"
          exit 1
        fi
    - name: Parse platforms
      id: parse-platforms
      run: |
        # remove all empty lines
        result=$(echo "${{ inputs.platforms }}" | sed '/^$/d')
        # replace newlines with commas, remove trailing comma
        result=$(echo "${result}" | tr '\n' ',' | sed 's/,$//')
        echo "platforms=${result}" >> $GITHUB_OUTPUT
    - name: Extract metadata
      id: meta
      uses: docker/metadata-action@v5
      with:
        sep-tags: ','
        images: |
          ${{ inputs.docker_registry }}/${{ github.repository_owner }}/${{ inputs.image_name }}
    - name: Set up QEMU
      uses: docker/setup-qemu-action@v3
      if: ${{ needs.check.outputs.rebuild == 'true' || inputs.force_rebuild }}
      with:
        image: tonistiigi/binfmt:latest
        platforms: all
    - name: Set up Docker Buildx
      uses: docker/setup-buildx-action@v3
      if: ${{ needs.check.outputs.rebuild == 'true' || inputs.force_rebuild }}
    - name: Login to DockerHub
      uses: docker/login-action@v3
      if: ${{ needs.check.outputs.rebuild == 'true' || inputs.force_rebuild }}
      with:
        registry: ${{ inputs.docker_registry }}
        username: ${{ secrets.SA_GITHUB_USERNAME }}
        password: ${{ secrets.SA_GITHUB_PAT }}
    - name: Build and push
      uses: docker/build-push-action@v6
      if: ${{ needs.check.outputs.rebuild == 'true' || inputs.force_rebuild }}
      with:
        context: ${{ steps.get-context.outputs.path }}
        file: ${{ steps.get-context.outputs.path }}/${{ inputs.docker_file_name }}
        push: true
        tags: ${{ steps.meta.outputs.tags }}
        labels: ${{ steps.meta.outputs.labels }}    
        platforms: ${{ steps.parse-platforms.outputs.platforms }}
        cache-from: type=gha
        cache-to: type=gha,mode=max
        build-args: ${{ inputs.build_args }}
    - name: Extract one image tag
      id: extract-one-tag
      shell: python3 {0}
      run: |
        import os
        tags = "${{ steps.meta.outputs.tags }}".split(",")
        tags_short = [tag.split(":")[-1] for tag in tags]
        if len(tags_short) == 0:
          print("No tags found!❌")
          exit(1)
        tag_short = None
        for t in tags_short:
          if t.startswith("v"):
            tag_short = t
            break
        if tag_short is None:
          for t in tags_short:
            if not t.startswith("latest"):
              tag_short = t
              break
        if tag_short is None:
          tag_short = tags_short[0]
        if tag_short is None:
          print("No tag found!❌")
          exit(1)
        for t in tags:
          if t.endswith(tag_short):
            tag_long = t
            break
        with open(os.environ["GITHUB_OUTPUT"], "a") as f:
          f.write(f"tag_short={tag_short}\n")
          print(f"Set tag_short={tag_short}")
          f.write(f"tag_long={tag_long}\n")
          print(f"Set tag_long={tag_long}")