Use docker buildx to create multi-arch image (#2)

.github/workflows/docker-image.yml

@@ -11,10 +11,61 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
-    - name: Build and push Docker images
-      uses: docker/build-push-action@v1.1.0
+
+    - name: Prepare
+      id: prepare
+      run: |
+        DOCKER_IMAGE=averagemarcus/kube-image-prefetch
+        DOCKER_PLATFORMS=linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64,linux/386,linux/ppc64le,linux/s390x
+
+        VERSION=latest
+        if [[ $GITHUB_REF == refs/tags/* ]]; then
+          VERSION=${GITHUB_REF#refs/tags/v}
+        fi
+
+        TAGS="--tag ${DOCKER_IMAGE}:${VERSION}"
+        if [[ $VERSION =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]]; then
+          TAGS="$TAGS --tag ${DOCKER_IMAGE}:latest"
+        fi
+
+        echo ::set-output name=tags::${TAGS}
+        echo ::set-output name=platforms::${DOCKER_PLATFORMS}
+
+    - name: Set up Docker Buildx
+      uses: crazy-max/ghaction-docker-buildx@v3
+
+    - name: Cache Docker layers
+      uses: actions/cache@v2
+      id: cache
       with:
-        username: averagemarcus
-        password: ${{ secrets.DOCKER_TOKEN }}
-        repository: averagemarcus/kube-image-prefetch
-        tag_with_ref: true
+        path: /tmp/.buildx-cache
+        key: ${{ runner.os }}-buildx-${{ github.sha }}
+        restore-keys: |
+          ${{ runner.os }}-buildx-
+
+    - name: Docker Buildx (build)
+      run: |
+        docker buildx build \
+          --cache-from "type=local,src=/tmp/.buildx-cache" \
+          --cache-to "type=local,dest=/tmp/.buildx-cache" \
+          --platform ${{ steps.prepare.outputs.platforms }} \
+          --output "type=image,push=false" \
+          ${{ steps.prepare.outputs.tags }} \
+          .
+
+    - name: Docker Login
+      env:
+        DOCKER_USERNAME: averagemarcus
+        DOCKER_PASSWORD: ${{ secrets.DOCKER_TOKEN }}
+      run: |
+        echo "${DOCKER_PASSWORD}" | docker login --username "${DOCKER_USERNAME}" --password-stdin
+
+    - name: Docker Buildx (push)
+      run: |
+        docker buildx build \
+          --cache-from "type=local,src=/tmp/.buildx-cache" \
+          --cache-to "type=local,dest=/tmp/.buildx-cache" \
+          --platform ${{ steps.prepare.outputs.platforms }} \
+          --output "type=image,push=true" \
+          ${{ steps.prepare.outputs.tags }} \
+          .

Dockerfile

@@ -1,9 +1,11 @@
-FROM golang:1.14-alpine AS builder
+FROM --platform=${BUILDPLATFORM:-linux/amd64} tonistiigi/xx:golang AS xgo
+FROM --platform=${BUILDPLATFORM:-linux/amd64} golang:1.14-alpine AS builder
+COPY --from=xgo / /
 WORKDIR /app/
 ADD . .
-RUN GOOS=linux GOARCH=amd64 CGO_ENABLED=0 go build -ldflags="-w -s" -o kube-image-prefetch main.go
+RUN CGO_ENABLED=0 go build -ldflags="-w -s" -o kube-image-prefetch main.go
 
-FROM scratch
+FROM --platform=${TARGETPLATFORM:-linux/amd64} scratch
 WORKDIR /app/
 COPY --from=builder /app/kube-image-prefetch /app/kube-image-prefetch
 ENTRYPOINT ["/app/kube-image-prefetch"]

Makefile

@@ -2,6 +2,8 @@
 
 IMAGE ?= averagemarcus/kube-image-prefetch:latest
 
+export DOCKER_CLI_EXPERIMENTAL=enabled
+
 .PHONY: test # Run all tests, linting and format checks
 test: lint check-format run-tests
 
@@ -31,11 +33,20 @@ build: lint check-format fetch-deps
 
 .PHONY: docker-build # Build the docker image
 docker-build:
-	@docker build -t $(IMAGE) .
+	@docker buildx create --use --name=crossplat --node=crossplat && \
+	docker buildx build \
+		--output "type=docker,push=false" \
+		--tag $(IMAGE) \
+		.
 
 .PHONY: docker-publish # Push the docker image to the remote registry
 docker-publish:
-	@docker push $(IMAGE)
+	@docker buildx create --use --name=crossplat --node=crossplat && \
+	docker buildx build \
+		--platform linux/386,linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64,linux/ppc64le,linux/s390x \
+		--output "type=image,push=true" \
+		--tag $(IMAGE) \
+		.
 
 .PHONY: run # Run the application
 run: