Add GitHub Actions workflow to publish Docker image (#5)

Author: balhoff

.github/workflows/publish-docker-image.yaml

@@ -0,0 +1,55 @@
+name: Publish docker image
+
+on:
+  release:
+    types: [published]
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+
+  build:
+
+    runs-on: ubuntu-latest
+
+    permissions:
+      contents: read
+      packages: write
+      attestations: write
+      id-token: write
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v4
+
+    - name: Log in to the Container registry
+      uses: docker/login-action@65b78e6e13532edd9afa3aa52ac7964289d1a9c1
+      with:
+        registry: ${{ env.REGISTRY }}
+        username: ${{ github.actor }}
+        password: ${{ secrets.GITHUB_TOKEN }}
+
+    - name: Extract metadata (tags, labels) for Docker
+      id: meta
+      uses: docker/metadata-action@9ec57ed1fcdbf14dcef7dfbe97b2010124a938b7
+      with:
+        images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+
+    - name: Build and push Docker image
+      id: push
+      uses: docker/build-push-action@f2a1d5e99d037542a71f64918e516c093c6f3fc4
+      with:
+        context: .
+        push: true
+        tags: ${{ steps.meta.outputs.tags }}
+        labels: ${{ steps.meta.outputs.labels }}
+
+
+    - name: Generate artifact attestation
+      uses: actions/attest-build-provenance@v1
+      with:
+        subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME}}
+        subject-digest: ${{ steps.push.outputs.digest }}
+        push-to-registry: true