Switch to cross multiarch build

Author: randomairborne

.github/workflows/build.yml

@@ -1,49 +1,97 @@
-name: Build Service
+name: Build container
+
 on:
   push:
-    branches:
-      - main
   workflow_dispatch:
 
+env:
+  REGISTRY_IMAGE: ghcr.io/randomairborne/tinylevel
+
 permissions:
-  contents: read
   packages: write
+  contents: read
 
 jobs:
   check:
     uses: ./.github/workflows/check.yml
+
   build:
-    needs: [check]
+    needs: [ check ]
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        platform:
+          - docker: linux/amd64
+            llvm: x86_64
+          - docker: linux/arm64
+            llvm: aarch64
     steps:
-      - name: Correct env
-        run: echo "REPO=${GITHUB_REPOSITORY,,}" >>${GITHUB_ENV}
-
-      - name: Check out code into the proper directory
+      - name: Check out code
         uses: actions/checkout@v4
 
       - name: Set up Docker Buildx
-        id: buildx
         uses: docker/setup-buildx-action@v3
 
-      - name: Login to GitHub Container Registry
+      - name: Log in to GitHub Container Registry
         uses: docker/login-action@v3
         with:
           registry: ghcr.io
           username: ${{ github.repository_owner }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
-      - name: Build container
-        uses: docker/build-push-action@v5
+      - name: Build and push by digest
+        id: build
+        uses: docker/build-push-action@v6
         with:
           context: .
-          push: true
-          tags: ghcr.io/${{ env.REPO }}:latest,ghcr.io/${{ env.REPO }}:git-${{ github.sha }}
-          platforms: linux/amd64
-          cache-from: type=gha
-          cache-to: type=gha,mode=max
+          platforms: ${{ matrix.platform.docker }}
+          build-args: |
+            LLVMTARGETARCH=${{ matrix.platform.llvm }}
+          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/${digest#sha256:}"
+
+      - name: Upload digest
+        uses: actions/upload-artifact@v4
+        with:
+          name: digests-${{ matrix.platform.llvm }}
+          path: /tmp/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: /tmp/digests
+          pattern: digests-*
+          merge-multiple: true
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to GitHub Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Create manifest list and push
+        working-directory: /tmp/digests
+        run: |
+          docker buildx imagetools create --tag ${{ env.REGISTRY_IMAGE }}:latest --tag ${{ env.REGISTRY_IMAGE }}:git-${{ github.sha }} $(printf '${{ env.REGISTRY_IMAGE }}@sha256:%s ' *)
+
   deploy:
-    needs: [build]
+    needs: [ merge ]
     runs-on: ubuntu-latest
     steps:
       - name: Correct env

Dockerfile

@@ -1,32 +1,28 @@
-FROM ghcr.io/randomairborne/asset-squisher:latest AS client-builder
-
-COPY /assets/ /uncompressed-assets/
+ARG LLVMTARGETARCH
+FROM --platform=${BUILDPLATFORM} ghcr.io/randomairborne/cross-cargo-${LLVMTARGETARCH}:latest AS server-builder
 
-RUN asset-squisher /uncompressed-assets/ /assets/
-
-FROM rust:alpine AS server-builder
+ARG LLVMTARGETARCH
 
 WORKDIR /build
+
 COPY . .
 
-RUN apk add musl-dev
+RUN cargo build --release --target ${LLVMTARGETARCH}-unknown-linux-musl
 
-RUN cargo version
+FROM ghcr.io/randomairborne/asset-squisher:latest AS client-builder
 
-RUN \
-    --mount=type=cache,target=/build/target/ \
-    --mount=type=cache,target=/usr/local/cargo/registry/ \
-    cargo build --release && cp /build/target/release/mcping /build/mcping
+COPY /assets/ /uncompressed-assets/
 
-FROM alpine:latest
+RUN asset-squisher /uncompressed-assets/ /assets/
+
+FROM scratch
+ARG LLVMTARGETARCH
 
 WORKDIR /
 
-COPY --from=server-builder /build/mcping /usr/bin/mcping
+COPY --from=server-builder /build/target/${LLVMTARGETARCH}-unknown-linux-musl/release/mcping /usr/bin/mcping
 COPY --from=client-builder /assets/ /var/www/mcping/
 
-EXPOSE 8080
-ENV ASSET_DIR="/var/www/mcping/"
-
-CMD ["/usr/bin/mcping"]
+COPY --from=builder /build/target/${LLVMTARGETARCH}-unknown-linux-musl/release/mcping /usr/bin/mcping
 
+ENTRYPOINT ["/usr/bin/mcping"]