build.yml

name: build

# Publishes images to GitHub Container Registry. By default only the slim image
# (org.openprojectx.* Maven artifacts) is built. The full image (full Maven build with all
# deps + jars) is opt-in: trigger the workflow manually with "build_full" enabled.
on:
  push:
    branches: [ main, master ]
    tags: [ 'v*' ]
  pull_request:
  workflow_dispatch:
    inputs:
      build_full:
        description: 'Also build and push the full (heavy) image'
        type: boolean
        default: false

env:
  REGISTRY: ghcr.io
  IMAGE_NAME: ${{ github.repository }}
  # Print the full, uncollapsed output of every build instruction (no TUI grouping).
  BUILDKIT_PROGRESS: plain

jobs:
  build:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      # Push everywhere except on pull requests (PRs from forks can't access GHCR).
      - name: Log in to GitHub Container Registry
        if: github.event_name != 'pull_request'
        uses: docker/login-action@v3
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      # First 8 characters of the commit hash, used as an image tag.
      - name: Short commit SHA
        id: vars
        run: echo "short_sha=${GITHUB_SHA:0:8}" >> "$GITHUB_OUTPUT"

      # Full image: opt-in only (manual run with build_full=true). Disabled by default.
      - name: Docker metadata
        id: meta
        if: ${{ inputs.build_full }}
        uses: docker/metadata-action@v5
        with:
          # metadata-action lowercases the image name, so mixed-case owners are fine.
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=ref,event=branch
            type=ref,event=tag
            type=sha
            type=raw,value=${{ steps.vars.outputs.short_sha }}
            type=raw,value=latest,enable={{is_default_branch}}

      # The Dockerfile runs `mvn install` (install the deps and build in the image build),
      # keeping the downloaded deps, built jars and source inside the published image.
      - name: Build and push image
        if: ${{ inputs.build_full }}
        uses: docker/build-push-action@v6
        with:
          context: .
          push: ${{ github.event_name != 'pull_request' }}
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          cache-from: type=gha
          cache-to: type=gha,mode=max

      # Same image repo, tags suffixed with -slim (e.g. latest-slim, <shortsha>-slim).
      - name: Docker metadata (slim)
        id: meta-slim
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          flavor: |
            suffix=-slim,onlatest=true
          tags: |
            type=ref,event=branch
            type=ref,event=tag
            type=sha
            type=raw,value=${{ steps.vars.outputs.short_sha }}
            type=raw,value=latest,enable={{is_default_branch}}

      # The slim image only populates the Maven local repo with the org.openprojectx.* artifacts.
      - name: Build and push slim image
        uses: docker/build-push-action@v6
        with:
          context: .
          file: Dockerfile.slim
          push: ${{ github.event_name != 'pull_request' }}
          tags: ${{ steps.meta-slim.outputs.tags }}
          labels: ${{ steps.meta-slim.outputs.labels }}
          cache-from: type=gha,scope=slim
          cache-to: type=gha,mode=max,scope=slim