Github actions: build for arm too

.github/workflows/build.yml

@@ -7,27 +7,101 @@ on:
   workflow_dispatch:
 
 jobs:
-  docker:
-    runs-on: ubuntu-latest
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-24.04-arm
+            platform: arm64
+          - os: ubuntu-24.04
+            platform: amd64
+
+    runs-on: ${{ matrix.os }}
     steps:
-      - name: Checkout
-        uses: actions/checkout@v4
+      - name: Prepare
+        run: |
+          platform=${{ matrix.platform }}
+          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV
+
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: |
+            ${{ vars.DOCKERHUB_REPO }}
 
       - name: Login to Docker Hub
         uses: docker/login-action@v3
         with:
-          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          username: ${{ vars.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
 
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
 
-      - name: Build and push
+      - name: Build and push by digest
+        id: build
         uses: docker/build-push-action@v6
         with:
-          context: .
-          push: true
+          platforms: "${{ matrix.platform }}"
+          labels: ${{ steps.meta.outputs.labels }}
+          outputs: type=image,"name=${{ vars.DOCKERHUB_REPO }}",push-by-digest=true,name-canonical=true,push=true
+
+      - name: Export digest
+        run: |
+          mkdir -p ${{ runner.temp }}/digests
+          digest="${{ steps.build.outputs.digest }}"
+          touch "${{ runner.temp }}/digests/${digest#sha256:}"
+
+      - name: Upload digest
+        uses: actions/upload-artifact@v4
+        with:
+          name: digests-${{ env.PLATFORM_PAIR }}
+          path: ${{ runner.temp }}/digests/*
+          if-no-files-found: error
+          retention-days: 1
+  merge:
+    runs-on: ubuntu-latest
+    needs:
+      - build
+    steps:
+      - name: Download digests
+        uses: actions/download-artifact@v4
+        with:
+          path: ${{ runner.temp }}/digests
+          pattern: digests-*
+          merge-multiple: true
+
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ vars.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: |
+            ${{ vars.DOCKERHUB_REPO }}
           tags: |
-            liv2/amiga-gcc:latest
-            liv2/amiga-gcc:${{ github.ref_name }}
-            liv2/amiga-gcc:${{ github.sha }}
+            type=raw,value=latest,enable=${{ github.ref == format('refs/heads/{0}', 'main') }}
+            type=sha
+            type=ref,event=branch
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}            
+
+      - name: Create manifest list and push
+        working-directory: ${{ runner.temp }}/digests
+        run: |
+          docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
+            $(printf '${{ vars.DOCKERHUB_REPO }}@sha256:%s ' *)       
+
+      - name: Inspect image
+        run: |
+          docker buildx imagetools inspect ${{ vars.DOCKERHUB_REPO }}:${{ steps.meta.outputs.version }}