dockerhub support (#1)

.github/workflows/release.yml

@@ -1,6 +1,7 @@
 name: release
 
 on:
+  workflow_dispatch: ~
   push:
     branches: [main]
 
@@ -52,3 +53,43 @@ jobs:
           subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
           subject-digest: ${{ steps.docker-push.outputs.digest }}
           push-to-registry: true
+
+  docker-hub:
+    runs-on: ubuntu-latest
+    env:
+      REGISTRY: index.docker.io
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Extract metadata (tags, labels)
+        id: docker-meta
+        uses: docker/metadata-action@8e5442c4ef9f78752691e2d8f8d19755c6f78e81  # v5.5.1
+        with:
+          images: ${{ secrets.DOCKERHUB_USERNAME }}/${{ github.event.repository.name }}
+          tags: |
+            type=raw,value=latest,enable=true
+            type=ref,enable=true,prefix=,suffix=,event=tag
+
+      - name: Build and push image
+        id: docker-push
+        uses: docker/build-push-action@2cdde995de11925a030ce8070c3d77a52ffcf1c0  # v5.3.0
+        with:
+          context: .
+          push: true
+          tags: ${{ steps.docker-meta.outputs.tags }}
+          labels: ${{ steps.docker-meta.outputs.labels }}
+
+      - name: Attest image
+        uses: github-early-access/generate-build-provenance@main
+        with:
+          subject-name: ${{ env.REGISTRY }}/${{ secrets.DOCKERHUB_USERNAME }}/${{ github.event.repository.name }}
+          subject-digest: ${{ steps.docker-push.outputs.digest }}
+          push-to-registry: true

Dockerfile

@@ -1,2 +1,2 @@
-FROM ubuntu:22.04
+FROM alpine:latest
 RUN echo 'Hello, World!'