build multi-arch Docker image for linux/amd64 and linux/arm64

Adds multi-arch Docker image support, and defaults to building
for linux/amd64 and linux/arm64. Uses the docker buildx plugin
along with go cross-compilation.

Closes projectcontour#2868

Signed-off-by: Steve Kriss <[email protected]>

.github/workflows/build_main.yaml

@@ -10,6 +10,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v1
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v1
+      with:
+        version: latest
     - name: Build and Push to registry
       env:
         DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
@@ -19,5 +23,5 @@ jobs:
         TAG_LATEST: "false"
       run: |
         echo "$DOCKER_PASSWORD" | docker login -u "$DOCKER_USERNAME" --password-stdin
-        make push
+        make multiarch-build-push
         docker logout

.github/workflows/build_tag.yaml

@@ -17,6 +17,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v1
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v1
+      with:
+        version: latest
     - name: Build and Push to registry
       env:
         DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}

Dockerfile

@@ -1,4 +1,6 @@
-FROM golang:1.15.2 AS build
+ARG BUILDPLATFORM=linux/amd64
+
+FROM --platform=$BUILDPLATFORM golang:1.15.2 AS build
 WORKDIR /contour
 
 ENV GOPROXY=https://proxy.golang.org
@@ -13,13 +15,16 @@ COPY Makefile Makefile
 ARG BUILD_BRANCH
 ARG BUILD_SHA
 ARG BUILD_VERSION
+ARG TARGETOS
+ARG TARGETARCH
 
-RUN make install \
+RUN make build \
 	    CGO_ENABLED=0 \
-	    GOOS=linux \
+		GOOS=${TARGETOS} \
+		GOARCH=${TARGETARCH} \
 	    BUILD_VERSION=${BUILD_VERSION} \
 	    BUILD_SHA=${BUILD_SHA} \
 	    BUILD_BRANCH=${BUILD_BRANCH}
 
 FROM scratch AS final
-COPY --from=build /go/bin/contour /bin/contour
+COPY --from=build /contour/contour /bin/contour

Makefile

@@ -16,6 +16,19 @@ JEKYLL_PORT := 4000
 JEKYLL_LIVERELOAD_PORT := 35729
 
 TAG_LATEST ?= false
+
+ifeq ($(TAG_LATEST), true)
+	IMAGE_TAGS = \
+		--tag $(IMAGE):$(VERSION) \
+		--tag $(IMAGE):latest
+else
+	IMAGE_TAGS = \
+		--tag $(IMAGE):$(VERSION)
+endif
+
+# Platforms to build the multi-arch image for.
+IMAGE_PLATFORMS ?= linux/amd64,linux/arm64
+
 # Used to supply a local Envoy docker container an IP to connect to that is running
 # 'contour serve'. On MacOS this will work, but may not on other OSes. Defining
 # LOCALIP as an env var before running 'make local' will solve that.
@@ -71,6 +84,9 @@ check: install check-test check-test-race ## Install and run tests
 .PHONY: checkall
 checkall: vendor check lint check-generate
 
+build: ## Build the contour binary
+	go build -mod=readonly -v -ldflags="$(GO_LDFLAGS)" $(GO_TAGS) $(MODULE)/cmd/contour
+
 install: ## Build and install the contour binary
 	go install -mod=readonly -v -ldflags="$(GO_LDFLAGS)" $(GO_TAGS) $(MODULE)/cmd/contour
 
@@ -84,6 +100,17 @@ download: ## Download Go modules
 vendor:
 	go mod vendor
 
+multiarch-build-push: ## Build and push a multi-arch Contour container image to the Docker registry
+	docker buildx build \
+		--platform $(IMAGE_PLATFORMS) \
+		--build-arg "BUILD_VERSION=$(BUILD_VERSION)" \
+		--build-arg "BUILD_BRANCH=$(BUILD_BRANCH)" \
+		--build-arg "BUILD_SHA=$(BUILD_SHA)" \
+		$(DOCKER_BUILD_LABELS) \
+		$(IMAGE_TAGS) \
+		--push \
+		.
+
 container: ## Build the Contour container image
 	docker build \
 		--build-arg "BUILD_VERSION=$(BUILD_VERSION)" \

hack/actions/build-and-push-release-images.sh

@@ -6,7 +6,7 @@ set -o pipefail
 
 # This scripts sets TAG_LATEST based on whether the tag currently being
 # built is the highest semantic version tag that's not a pre-release
-# (alpha, beta, rc), and calls 'make push'.
+# (alpha, beta, rc), and calls 'make multiarch-build-push'.
 #
 # This script is intended to be run only for tag builds and will no-op
 # if GITHUB_REF is not in the format "refs/tags/<tag-name>".
@@ -54,4 +54,4 @@ echo "CURRENT_TAG: $CURRENT_TAG"
 echo "HIGHEST_SEMVER_TAG: $HIGHEST_SEMVER_TAG"
 echo "TAG_LATEST: $TAG_LATEST"
 
-make push TAG_LATEST="$TAG_LATEST"
+make multiarch-build-push TAG_LATEST="$TAG_LATEST"