feat: multi arch builds, using nonstandard workflow for now (#177)

* feat: multi arch builds, using nonstandard workflow for now

* fix: dockerfile multiarch fix

Author: rswanson

.github/workflows/ghcr.yml

@@ -3,17 +3,124 @@ name: Release GHCR
 on:
   release:
     types: [published]
-  push:
-    branches:
-      - swanny-ghcr
   workflow_dispatch:
 
-# simplest example of using the rust-base action
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
 jobs:
-  ghcr-release:
-    uses: init4tech/actions/.github/workflows/ghcr.yml@main
+  build-and-push:
+    runs-on:
+      group: ${{ matrix.group }}
     permissions:
-        contents: read
-        packages: write
-        attestations: write
-        id-token: write
+      contents: read
+      packages: write
+      attestations: write
+      id-token: write
+    strategy:
+      matrix:
+        include:
+          - platform: linux/amd64
+            group: amd64-large-runners
+          - platform: linux/arm64
+            group: arm64-large-runners
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          tags: |
+            type=ref,event=branch
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+            type=semver,pattern={{major}}
+            type=sha
+
+      - name: Build and push Docker image by digest
+        id: build
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          platforms: ${{ matrix.platform }}
+          labels: ${{ steps.meta.outputs.labels }}
+          outputs: type=image,name=${{ env.REGISTRY }}/${{ env.IMAGE_NAME }},push-by-digest=true,name-canonical=true,push=true
+          cache-from: type=gha,scope=build-${{ matrix.platform }}
+          cache-to: type=gha,mode=max,scope=build-${{ matrix.platform }}
+      - name: Export digest
+        run: |
+          mkdir -p /tmp/digests
+          digest="${{ steps.build.outputs.digest }}"
+          touch "/tmp/digests/${digest#sha256:}"
+
+      - name: Upload digest
+        uses: actions/upload-artifact@v4
+        with:
+          name: digests-${{ strategy.job-index }}
+          path: /tmp/digests/*
+          if-no-files-found: error
+          retention-days: 1
+
+  merge-and-push:
+    runs-on: ubuntu-latest
+    needs: build-and-push
+    permissions:
+      contents: read
+      packages: write
+      attestations: write
+      id-token: write
+    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 Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          tags: |
+            type=ref,event=branch
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+            type=semver,pattern={{major}}
+            type=sha
+
+      - 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 }}/${{ env.IMAGE_NAME }}@sha256:%s ' *)
+
+      - name: Inspect image
+        run: |
+          docker buildx imagetools inspect ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ steps.meta.outputs.version }}

Dockerfile

@@ -2,7 +2,7 @@
 ### STAGE 0: Create base chef image for building
 ### Use a Debian bookworm-based Rust image so GLIBC matches the final runtime (bookworm ships glibc 2.36)
 ### cargo-chef is then installed into this pinned base
-FROM --platform=$TARGETPLATFORM rust:bookworm AS chef
+FROM --platform=$BUILDPLATFORM rust:bookworm AS chef
 
 RUN cargo install cargo-chef
 
@@ -33,7 +33,7 @@ COPY --exclude=target . .
 RUN --mount=type=ssh cargo build --release --bin zenith-builder-example
 
 # Stage 3: Final image for running in the env
-FROM --platform=$TARGETPLATFORM debian:bookworm-slim
+FROM --platform=$BUILDPLATFORM debian:bookworm-slim
 RUN apt-get update && apt-get -y upgrade && apt-get install -y \
 		libssl-dev \
 		ca-certificates