Switch docker push to be triggered on new release

.github/workflows/docker_crossbuild_publish.yml

@@ -1,11 +1,12 @@
 name: Cross-Compile Docker Build and Push
 
 on:
-  pull_request:
-    types:
-      - opened
-      - synchronize
-      - closed
+  release:
+    types: [published]
+  workflow_dispatch:
+
+env:
+  REGISTRY_IMAGE: ergoplatform/oracle-core
 
 jobs:
  build:
@@ -23,45 +24,78 @@ jobs:
        uses: actions/checkout@v3
 
      - name: Set up Docker Buildx
-       uses: docker/setup-buildx-action@v1
+       uses: docker/setup-buildx-action@v2
 
      - name: Generate Docker metadata
        id: metadata
-       uses: docker/metadata-action@v3
+       uses: docker/metadata-action@v4
        with:
-         images: greenden/oracle-core
-         tags: |
-           type=ref,event=tag
-     - name: Build images
-       uses: docker/build-push-action@v3
+         images: ${{ env.REGISTRY_IMAGE }}
+
+     - name: Login to DockerHub
+       uses: docker/login-action@v2
+       with:
+         username: ${{ secrets.DOCKERHUB_USERNAME }}
+         password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+     - name: Build and push by digest
+       id: build
+       uses: docker/build-push-action@v4
        with:
          context: .
          platforms: ${{ matrix.platform }}
-         tags: ${{ steps.metadata.outputs.tags }}
+         labels: ${{ steps.metadata.outputs.labels }}
+         outputs: type=image,name=${{ env.REGISTRY_IMAGE }},push-by-digest=true,name-canonical=true,push=true
          build-args: |
            TARGETPLATFORM=${{ matrix.platform }}
            CCARCH=${{ matrix.ccarch }}
-         push: false
-         load: true
-
- push:
+
+     - name: Export digest
+       run: |
+          mkdir -p /tmp/digests
+          digest="${{ steps.build.outputs.digest }}"
+          touch "/tmp/digests/${digest#sha256:}"
+
+     - name: Upload digest
+       uses: actions/upload-artifact@v3
+       with:
+         name: digests
+         path: /tmp/digests/*
+         if-no-files-found: error
+         retention-days: 1    
+
+ merge:
    needs: build
    runs-on: ubuntu-latest
    steps:
+     - name: Download digests
+       uses: actions/download-artifact@v3
+       with:
+         name: digests
+         path: /tmp/digests
+
      - name: Set up Docker Buildx
-       uses: docker/setup-buildx-action@v1
-
+       uses: docker/setup-buildx-action@v2
+
+     - name: Generate Docker metadata
+       id: metadata
+       uses: docker/metadata-action@v4
+       with:
+         images: ${{ env.REGISTRY_IMAGE }}
+         flavor: |
+           latest=true
+
      - name: Login to DockerHub
        uses: docker/login-action@v2
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}
 
-     - name: Combine and Push to DockerHub
-       uses: docker/build-push-action@v3
-       with:
-         context: .
-         platforms: linux/amd64,linux/arm64
-         tags: greenden/oracle-core:${{ github.ref_name }}, greenden/oracle-core:latest
-         push: true
-
+     - name: Create manifest list and push
+       working-directory: /tmp/digests
+       run: |
+         docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
+           $(printf '${{ env.REGISTRY_IMAGE }}@sha256:%s ' *)
+     - name: Inspect image
+       run: |
+         docker buildx imagetools inspect ${{ env.REGISTRY_IMAGE }}:${{ steps.metadata.outputs.version }}