snapshot.yml

name: Publish Snapshot

# Publishes a -SNAPSHOT build to GitHub Packages on every push to main.
# Only the starter library is deployed; the sample application is skipped
# via <maven.deploy.skip>true</maven.deploy.skip> in its POM.
#
# Consumers can resolve snapshots by adding to their build:
#   repository: https://maven.pkg.github.com/patbaumgartner/embabel-workflow-visualizer
#   (requires a GitHub PAT with read:packages scope)

on:
  push:
    branches: [main]

permissions:
  contents: read
  packages: write

jobs:
  publish:
    name: Deploy Snapshot (Java 21)
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Set up JDK 21
        uses: actions/setup-java@v4
        with:
          distribution: temurin
          java-version: '21'
          cache: maven
          # Writes ~/.m2/settings.xml with <server id="github"> credentials
          # so that mvn deploy can authenticate with GitHub Packages.
          server-id: github
          server-username: GITHUB_ACTOR
          server-password: GITHUB_TOKEN

      - name: Guard — only deploy snapshots
        run: |
          VERSION=$(mvn help:evaluate -Dexpression=project.version -q -DforceStdout)
          if [[ "$VERSION" != *-SNAPSHOT ]]; then
            echo "::notice::Skipping deploy — '$VERSION' is not a -SNAPSHOT version."
            exit 0
          fi
          echo "Deploying snapshot $VERSION"

      - name: Deploy
        run: mvn -B -DskipTests deploy
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}