adding a docker build job.

.github/workflows/build.yaml

@@ -0,0 +1,69 @@
+name: Docker
+on:
+  push:
+    branches: [ main, sandbox ]
+    # Publish semver tags as releases.
+    tags: [ 'v*.*.*' ]
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  omnibus:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+#      - name: "Populate frontend version information"
+#        run: "cd webapp/frontend && ./git.version.sh"
+#      - name: "Generate frontend & version information"
+#        uses: addnab/docker-run-action@v3
+#        with:
+#          image: node:lts
+#          options: -v ${{ github.workspace }}:/work
+#          run: |
+#            cd /work
+#            make binary-frontend && echo "print contents of /work/dist" && ls -alt /work/dist
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+        with:
+          platforms: 'arm64,arm'
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+      # Login against a Docker registry except on PR
+      # https://github.com/docker/login-action
+      - name: Log into registry ${{ env.REGISTRY }}
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v2
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      # Extract metadata (tags, labels) for Docker
+      # https://github.com/docker/metadata-action
+      - name: Extract Docker metadata
+        id: meta
+        uses: docker/metadata-action@v4
+        with:
+          tags: |
+            type=ref,enable=true,event=branch
+            type=ref,enable=true,event=tag
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+      # Build and push Docker image with Buildx (don't push on PR)
+      # https://github.com/docker/build-push-action
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v3
+        with:
+          platforms: linux/amd64,linux/arm64
+          context: .
+          file: docker/Dockerfile
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+#          cache-from: type=gha
+#          cache-to: type=gha,mode=max