'multi-arch' windows-gmsa-webhook container image to support arm64.

[chengliangli0918]

Currently windows-gmsa-webhook container image in upstream only supports amd64. AKS supports ARM64 Ubuntu/Mariner nodes. So when customer creates an AKS cluster with windows-gmsa enabled (e.g. az aks create --enable-windows-gmsa --node-vm-size <arm64_SKU>...), the windows-gmsa-webhook pod cannot start on arm64 Linux nodes. We need 'multi-arch' windows-gmsa-webhook container image so that windows-gmsa feature can work properly on AKS arm64 cluster, just like any other addon container images used on AKS linux nodes.

Use coredns 'multi-arch' container images as an example blow.

[jsturtevant]

This might just work if we update the GOARCH variable to be configurable in the dockerfile, pass that through the makefile, and create a manfest in the makefile when pushing.

windows-gmsa/admission-webhook/dockerfiles/Dockerfile

Line 16 in fa115c8

RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -ldflags="-w -s -X main.version=${VERSION}"

windows-gmsa/admission-webhook/make/image.mk

Lines 10 to 17 in fa115c8

	image_build:
	$(DOCKER_BUILD) -f dockerfiles/Dockerfile -t $(WEBHOOK_IMG):$(TAG)
	docker tag $(WEBHOOK_IMG):$(TAG) $(WEBHOOK_IMG):latest
	.PHONY: image_push
	image_push:
	docker push $(WEBHOOK_IMG):$(TAG)
	docker push $(WEBHOOK_IMG):latest

We might want a CI job eventually, but I don't think github actions supports ARM64 right now.

[chengliangli0918]

azure-cni seems to use github action to build, they started to build 'multi-arch' container images 20 months ago since this PR
Azure/azure-container-networking#1030

[marosset]

This might just work if we update the GOARCH variable to be configurable in the dockerfile, pass that through the makefile, and create a manfest in the makefile when pushing.

I tested this by setting GOARCH=arm64 and it looks like everything build correctly.

I can work on building / publishing a multi-arch image with linux/amd64 and linux/arm64 arches but I probably won't be able to do it until next week (week of May 15)

[jsturtevant]

azure-cni seems to use github action to build, they started to build 'multi-arch' container images 20 months ago since this PR

building on github actions should work, but we won't be able to run CI tests against it.

[chengliangli0918]

@marosset any update on 'multi-arch' windows-gmsa-webhook' container image?

[marosset]

Working on it now :)