add docker image build

Signed-off-by: Nicklas Körtge <[email protected]>

.github/workflows/backend.yml

@@ -15,6 +15,10 @@ on:
     branches: [ "main" ]
   workflow_dispatch:
 
+env:
+  REGISTRY: "ghcr.io"
+  IMAGE_NAME: "cbomkit"
+
 jobs:
   build:
     runs-on: ubuntu-latest
@@ -56,6 +60,29 @@ jobs:
         run: mvn clean package
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+        tags: |
+          type=ref,event=branch
+          type=semver,pattern={{version}}
+          type=semver,pattern={{major}}.{{minor}}
+      - name: Log in to the Container registry
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Build and push
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
       # Optional: Uploads the full dependency graph to GitHub to improve the quality of Dependabot alerts this repository can receive
       - name: Update dependency graph
         uses: advanced-security/maven-dependency-submission-action@v4