docker.yml

#
name: Build Docker image and push to GitHub Packages

# This workflow file is adapted from the example at https://docs.github.com/en/packages/managing-github-packages-using-github-actions-workflows/publishing-and-installing-a-package-with-github-actions#upgrading-a-workflow-that-accesses-a-registry-using-a-personal-access-token
on:
  push:
    branches:
      - main
    # Only rebuild if the Dockerfile or dependencies change.
    paths:
      - '.devcontainer/**'
      - 'python/servo/platform/linux_packages/**'
  workflow_dispatch:

jobs:
  devcontainer_ubuntu:
    runs-on: ubuntu-latest
    # We probably don't want to spam the package registry of every developer
    # thats working on servo and has actions enabled on their fork.
    # You can comment this if to test changes to the workflow locally in your fork,
    # use manual workflow dispatch in your fork.
    if: github.repository_owner == 'servo' || github.event_name == 'workflow_dispatch'
    permissions:
      packages: write
      contents: read
    env:
      IMAGE_NAME: devcontainer-ubuntu
    steps:
      - uses: actions/checkout@v6

      - name: Build image
        run: docker build . --file .devcontainer/Ubuntu.Dockerfile --tag ${{ env.IMAGE_NAME }} --label "runnumber=${GITHUB_RUN_ID}"

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

      - name: Push image
        run: |
          IMAGE_ID=ghcr.io/${{ github.repository_owner }}/servo/$IMAGE_NAME

          # This changes all uppercase characters to lowercase.
          IMAGE_ID=$(echo $IMAGE_ID | tr '[A-Z]' '[a-z]')
          # This strips the git ref prefix from the version.
          VERSION=$(echo "${{ github.ref }}" | sed -e 's,.*/\(.*\),\1,')

          # This uses the Docker `latest` tag convention.
          [ "$VERSION" == "main" ] && VERSION=latest
          echo IMAGE_ID=$IMAGE_ID
          echo VERSION=$VERSION
          # Todo: It would be nice to add another tag here, that has a version number, or a date-tag.
          docker tag $IMAGE_NAME $IMAGE_ID:$VERSION
          docker push $IMAGE_ID:$VERSION