docker.yaml

name: Build a Docker Image First
on:
  push:
    # Will trigger on MERGES (or pushes) to main branch.
    branches:
    - 'main'
  pull_request:
    # Will ALSO trigger any time a PR is opened merging to main.
    # Specify '*' here to merge on PRs being opened against ANY branch.
    branches:
    - 'main'

# This creates environment variables that can be shared between all the jobs.
env:
  # This will use docker.io for Dockerhub if empty, so we want to tell it to
  # use the github one (ghcr.io which stands for... GitHub Container Registry)
  REGISTRY: ghcr.io
  # Name the docker image after the repo: github.repository as <account>/<repo>
  IMAGE_NAME: ${{ github.repository }}

jobs:
  # First we'll build the docker image in a separate job. Then we actually
  # build the code in a separate job.
  docker:
    runs-on: ubuntu-latest
    # Note that here we DON'T have a container because github refuses to allow
    # us to do docker-in-docker. So docker build runs natively on the machine.
    # The outputs tags gives us an output variabel that can be used in other
    # jobs. In this case, it's the name of the docker file.
    outputs:
      docker_image_name: ${{ steps.meta.outputs.tags }}
    steps:
    - name: Check out repository
      # We still need to do this to actually build the docker file.
      uses: actions/checkout@v3
    - name: Set up Docker Buildx
      uses: docker/setup-buildx-action@v2
    - name: Log into registry ${{ env.REGISTRY }}
      # Github pre-populates all of these for you! So you don't have to do
      # anything fancy. Just make sure the env.REGISTRY is set to ghcr.io
      uses: docker/login-action@v2
      with:
        registry: ${{ env.REGISTRY }}
        username: ${{ github.actor }}
        password: ${{ secrets.GITHUB_TOKEN }}
    - name: Extract Docker metadata
      # This just figures out what to tag our docker file as. It's less
      # complicated than it looks, and you have a lot of flexibility in
      # how you build tags here.
      id: meta
      uses: docker/metadata-action@v5
      with:
        images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
    - name: Build and push docker
      uses: docker/build-push-action@v4
      with:
        context: toy_example_package/docker/
        file: toy_example_package/docker/Dockerfile
        push: true
        tags: ${{ steps.meta.outputs.tags }}
        labels: ${{ steps.meta.outputs.labels }}
        cache-from: type=gha
        cache-to: type=gha,mode=max

  # The name of the job is "build". All jobs run in SEPARATE containers, so
  # they may run on separate machines and have the workspace wiped inbetween.
  build:
    # You need to specify the dependency on the previous job (docker) here!
    needs: docker
    # Run on a github-hosted runner. To specify our own, select:
    # [self-hosted, linux] instead.
    runs-on: ubuntu-latest
    # This will now use the container we build above! The "needs" specifies that
    # this must be populated and finished by the other job before we can run.
    container: ${{ needs.docker.outputs.docker_image_name }}
    steps:
    # Name is optional, uses: specify which ACTION is used (basically github
    # macros). You can write your own! Use with: to specify extra parameters.
    - name: Check out repository
      uses: actions/checkout@v3
      with:
        # This path is relative to ${GITHUB_WORKSPACE}. You can also use
        # "/${HOME}/" if you want but be sure to have the leading slash.
        path: catkin_ws/src/toy_example_package
    - name: Setup workspace & install ROS dependencies
      # We can skip the other setup steps now because it's all in the docker.
      run: |
        cd ${GITHUB_WORKSPACE}/catkin_ws
        catkin init
        catkin config --extend "/opt/ros/noetic"
        catkin config --merge-devel
        rosdep update
        rosdep install --from-paths src --ignore-src -y --rosdistro noetic
        catkin config --cmake-args -DCMAKE_BUILD_TYPE=Release
      shell: bash
    - name: Catkin build
      # The working directory is reset for each individual run command, so just
      # be aware!
      run: |
        cd ${GITHUB_WORKSPACE}/catkin_ws
        catkin build --continue toy_example_package
      shell: bash