How to modify tags for multiple images from docker-bake.hcl

[benbrummer]

How to set tags for multistage images for an Laravel application. The images are almost identical, apart of CMD and HEALTHCHECK

dockerfile

FROM debian AS base
...

FROM base AS laravel
...

FROM base AS worker
...

FROM base AS scheduler
...

docker-bake.hcl

target app {
...
}

target worker {
...
}

target scheduler {
...
}

I would like to generate tags, which have as an prefix the target
e.g.

app/local:major-minor-minor
app/local:major-minor-minor-worker
app/local:major-minor-minor-scheduler

At the moment I call docker/metadata-action three times with bake-target:, but it is quite redundant. I can go further with some matrix but maybe there is some build-in feature for this, which I was not yet able to identify.

My project:

• https://github.com/benbrummer/dockerfiles/blob/octane-action/.github/workflows/bake.yaml
• https://github.com/benbrummer/dockerfiles/blob/octane-action/docker-bake.hcl
• https://github.com/benbrummer/dockerfiles/blob/octane-action/Dockerfile

Similar

• How To Assign Tags To Multiple Targets From Single Bake Call? #417
• Generating tags for multiple bake targets #398 (comment), did not work in github workflow but localy the replace would work.

[crazy-max]

I would suggest to put targets to build in a bake group like:

group "builds" {
  targets = ["app", "worker", "scheduler"]
}

target app {
...
}

target worker {
...
}

target scheduler {
...
}

Then you can use a GitHub Actions matrix to distribute solved targets of this group using our matrix subaction: https://github.com/docker/bake-action/tree/master/subaction/matrix

jobs:
  prepare:
    runs-on: ubuntu-latest
    outputs:
      matrix: ${{ steps.generate.outputs.matrix }}
    steps:
      -
        name: Checkout
        uses: actions/checkout@v5
      -
        name: Generate matrix
        id: generate
        uses: docker/bake-action/subaction/matrix@v6
        with:
          target: builds

  build:
    runs-on: ubuntu-latest
    needs:
      - prepare
    strategy:
      fail-fast: false
      matrix:
        include: ${{ fromJson(needs.prepare.outputs.matrix) }}
    steps:
      -
        name: Checkout
        uses: actions/checkout@v5
      -
        name: Docker meta
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: |
            name/app
          tags: |
            type=ref,event=branch
            type=ref,event=pr
            type=semver,pattern={{version}}
          flavor: |
            suffix=-${{ matrix.target }}
      -
        name: Build
        uses: docker/bake-action@v6
        with:
          files: |
            ./docker-bake.hcl
            cwd://${{ steps.meta.outputs.bake-file }}
          targets: ${{ matrix.target }}

[benbrummer]

The suffix looks interesting 🤔

The base image is the heavy one and the app, worker and scheduler are only CMD and Healthcheck. I had the assumption that it makes more sense to have a single bake-action. But a matrix before for metadata and afterwards for merging the platforms or your proposal to have a complete matrix seam to be the way to go.

The matrix subaction is already used for the platforms, but I will see if I can extend this for the targets

The bake-action how it is creently implemented.

      - name: Build
        id: bake
        uses: docker/bake-action@v6
        with:
          files: |
            ./docker-bake.hcl
            cwd://${{ runner.temp }}/bake-meta-app.json
            cwd://${{ runner.temp }}/bake-meta-scheduler.json
            cwd://${{ runner.temp }}/bake-meta-worker.json

Thank you for your support.