ci(docker): add initial workflow for creating multi platform Docker images (#8732)

Refs #5815

.github/workflows/docker-build-push.yml

@@ -0,0 +1,107 @@
+# inspired by https://securitylab.github.com/research/github-actions-preventing-pwn-requests/
+name: Build & Push SwaggerUI multi platform Docker image
+
+on:
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: Git tag
+        type: string
+        required: true
+
+env:
+  REGISTRY_IMAGE: swaggerapi/swagger-ui
+
+jobs:
+  build:
+    name: Build & Push SwaggerUI platform specific Docker images
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        platform:
+          # linux/amd64 is already built by Jenkins
+          - linux/arm/v6
+          - linux/arm/v7
+          - linux/arm64/v8
+          - linux/386
+          - linux/ppc64le
+          - linux/s390x
+
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          ref: ${{ inputs.tag }}
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v4
+        with:
+          images: ${{ env.REGISTRY_IMAGE }}
+
+      - name: Log in to DockerHub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKERHUB_SB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_SB_PASSWORD }}
+
+      - name: Build and push by digest
+        id: build
+        uses: docker/build-push-action@v4
+        with:
+          context: .
+          platforms: ${{ matrix.platform }}
+          outputs: type=image,name=${{ env.REGISTRY_IMAGE }},push-by-digest=true,name-canonical=true,push=true
+
+      - 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:
+    name: Merge platform specific Docker image into multi platform image
+    runs-on: ubuntu-latest
+    needs:
+      - build
+
+    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@v2
+
+      - name: Login to Docker Hub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKERHUB_SB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_SB_PASSWORD }}
+
+      - name: Create manifest list and push
+        working-directory: /tmp/digests
+        run: |
+          docker buildx imagetools create -t ${{ env.REGISTRY_IMAGE }}:${{ inputs.tag }} \
+            ${{ env.REGISTRY_IMAGE }}:${{ inputs.tag }} \
+            $(printf '${{ env.REGISTRY_IMAGE }}@sha256:%s ' *)
+
+      - name: Inspect image
+        run: |
+          docker buildx imagetools inspect ${{ env.REGISTRY_IMAGE }}:${{ inputs.tag }}