Docker GHA: Upload Docker images on release

.github/workflows/docker.yml

@@ -3,12 +3,41 @@ name: Docker
 on:
   push:
     branches: [ main ]
-  pull_request: {}
+  pull_request:
+    branches: [ main ]
+  release:
+    types: [ published ]
 
 jobs:
   docker:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
-    - name: Build Image
+
+    - uses: docker/metadata-action@v5
+      id: meta
+      with:
+        images: |
+          icinga/icinga-notifications
+        tags: |
+          type=ref,event=branch,enable={{is_default_branch}}
+          type=semver,pattern={{version}}
+          type=semver,pattern={{major}}.{{minor}}
+
+    - uses: docker/setup-qemu-action@v3
+
+    - uses: docker/setup-buildx-action@v3
+
+    - if: github.event_name != 'pull_request'
+      uses: docker/login-action@v3
+      with:
+        username: ${{ secrets.DOCKERHUB_USERNAME }}
+        password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+    - name: Build and push
       uses: docker/build-push-action@v6
+      with:
+        labels: ${{ steps.meta.outputs.labels }}
+        platforms: linux/amd64,linux/arm64
+        push: ${{ github.event_name != 'pull_request' }}
+        tags: ${{ steps.meta.outputs.tags }}