From 119e3c3854ee4339cc02d7ce9b9ab9adaec7c5da Mon Sep 17 00:00:00 2001
From: Dinar Valeev <dinar.valeev@absa.africa>
Date: Mon, 25 Jan 2021 17:48:13 +0100
Subject: [PATCH] Enable docker multiarch build

Build docker image for aarch64 and combine them into a single manifest

Signed-off-by: Dinar Valeev <dinar.valeev@absa.africa>
---
 .github/workflows/release.yaml |  5 +++--
 Dockerfile                     |  4 +++-
 Makefile                       | 35 ++++++++++++++++++++++++++++++++--
 3 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/release.yaml b/.github/workflows/release.yaml
index 7ffcfa8de8..e1bdc28c63 100644
--- a/.github/workflows/release.yaml
+++ b/.github/workflows/release.yaml
@@ -19,8 +19,9 @@ jobs:
         run: |
           export PATH=~/go/bin:$PATH
           docker login -u "${DOCKER_USER}" -p "${DOCKER_PASSWORD}"
-          make docker-build
-          make docker-push
+          make docker-build-multi
+          make docker-push-multi
+          make docker-manifest
       - uses: dave-mcconnell/helm-gh-pages-microservices@master
         with:
           access-token: ${{ secrets.CR_TOKEN }}
diff --git a/Dockerfile b/Dockerfile
index f6903ee493..fb6f0ea999 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,6 +2,8 @@
 FROM golang:1.15 as builder
 
 WORKDIR /workspace
+ARG GOARCH=amd64
+
 # Copy the Go Modules manifests
 COPY go.mod go.mod
 COPY go.sum go.sum
@@ -15,7 +17,7 @@ COPY api/ api/
 COPY controllers/ controllers/
 
 # Build
-RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 GO111MODULE=on go build -a -o manager main.go
+RUN CGO_ENABLED=0 GOARCH=${GOARCH} GOOS=linux GO111MODULE=on go build -a -o manager main.go
 
 # Use distroless as minimal base image to package the manager binary
 # Refer to https://github.com/GoogleContainerTools/distroless for more details
diff --git a/Makefile b/Makefile
index 1d408d26c8..869d3694b2 100644
--- a/Makefile
+++ b/Makefile
@@ -165,15 +165,38 @@ dns-tools: ## Run temporary dnstools pod for debugging DNS issues
 dns-smoke-test:
 	kubectl -n k8gb run -it --rm --restart=Never --image=infoblox/dnstools:latest dnstools --command -- /usr/bin/dig @k8gb-coredns roundrobin.cloud.example.com
 
+# build docker images for multiple architectures
+# useful for CI
+.PHONY: docker-build-multi
+docker-build-multi: test
+	$(call docker-build-arch,amd64)
+	$(call docker-build-arch,arm64)
+
+# push docker for multiple architectures
+.PHONY: docker-push-multi
+docker-push-multi:
+	$(call docker-push-arch,amd64)
+	$(call docker-push-arch,arm64)
+
+# create and push docker manifest
+.PHONY: docker-manifest
+docker-manifest: docker-push-multi
+	docker manifest create ${IMG} \
+		${IMG}-amd64 \
+		${IMG}-arm64
+	docker manifest annotate ${IMG} ${IMG}-arm64 \
+		--os linux --arch arm64
+	docker manifest push ${IMG}
+
 # build the docker image
 .PHONY: docker-build
 docker-build: test
-	docker build . -t $(IMG)
+	$(call docker-build-arch,amd64)
 
 # push the docker image
 .PHONY: docker-push
 docker-push:
-	docker push $(IMG)
+	$(call docker-push-arch,amd64)
 
 # build and push the docker image exclusively for testing using commit hash
 .PHONY: docker-test-build-push
@@ -412,6 +435,14 @@ define install-kustomize
 	$(eval KUSTOMIZE_PATH = $(GOBIN)/kustomize)
 endef
 
+define docker-build-arch
+	docker build --build-arg GOARCH=${1} . -t ${IMG}-${1}
+endef
+
+define docker-push-arch
+	docker push ${IMG}-${1}
+endef
+
 define docker-test-build-push
 	docker build . -t k8gb:$(COMMIT_HASH)
 	docker tag k8gb:$(COMMIT_HASH) $(REPO):v$(COMMIT_HASH)