# Makefile for creating and uploading CoreDNS docker image.
#
# First you should do a release and then call this Makefile to create and upload
# the image.
#
# 1. Reuse the issue for this release
# 2. In an issue give the command: /docker VERSION
#    Where VERSION is the version of the release.
# 3. (to test as release /docker -t VERSION can be used.
#
# To release we run, these target from the this Makefile.docker ordered like:
# * make release
# * make docker-push
#
# Testing docker is done e.g. via:
#
# export DOCKER_PASSWORD=<pass>
# export DOCKER_LOGIN=miek
# make VERSION=x.y.z DOCKER=miek -f Makefile.docker release docker-push

ifeq (, $(shell which curl))
    $(error "No curl in $$PATH, please install")
endif

# VERSION is the version we should download and use.
VERSION:=
# DOCKER is the docker image repo we need to push to.
DOCKER:=
NAME:=coredns
GITHUB:=https://github.com/coredns/coredns/releases/download
# mips is not in LINUX_ARCH because it's not supported by docker manifest. Keep this list in sync with the one in Makefile.release
LINUX_ARCH:=amd64 arm arm64 mips64le ppc64le s390x
DOCKER_IMAGE_NAME:=$(DOCKER)/$(NAME)
DOCKER_IMAGE_LIST_VERSIONED:=$(shell echo $(LINUX_ARCH) | sed -e "s~[^ ]*~$(DOCKER_IMAGE_NAME)\-&:$(VERSION)~g")
DOCKER_IMAGE_LIST_LATEST:=$(shell echo $(LINUX_ARCH) | sed -e "s~[^ ]*~$(DOCKER_IMAGE_NAME)\-&:latest~g")

all:
	@echo Use the 'release' target to download released binaries and build containers per arch, 'docker-push' to build and push a multi arch manifest.
	echo $(DOCKER_IMAGE_LIST_VERSIONED)
	echo $(DOCKER_IMAGE_LIST_LATEST)

release: image-download docker-build

.PHONY: image-download
image-download:
ifeq ($(VERSION),)
	$(error "Please specify a version use. Use VERSION=<version>")
endif

	@rm -rf build/docker
	@mkdir -p build/docker
	@# 1. Copy appropriate coredns binary to build/docker/<arch>
	@# 2. Copy Dockerfile into the correct dir as well.
	@# 3. Unpack the tgz from github into 'coredns' binary.
	for arch in $(LINUX_ARCH); do \
		mkdir build/docker/$${arch}; \
		curl -L $(GITHUB)/v$(VERSION)/coredns_$(VERSION)_linux_$${arch}.tgz > build/docker/$${arch}/coredns.tgz && \
			( cd build/docker/$${arch}; tar xf coredns.tgz && rm coredns.tgz ); \
			cp Dockerfile build/docker/$${arch} ; \
	done

.PHONY: docker-build
docker-build:
ifeq ($(DOCKER),)
	$(error "Please specify Docker registry to use. Use DOCKER=coredns for releases")
else
	docker version
	for arch in $(LINUX_ARCH); do \
	    docker build -t $(DOCKER_IMAGE_NAME)-$${arch}:$(VERSION) build/docker/$${arch}  && \
	    docker tag $(DOCKER_IMAGE_NAME)-$${arch}:$(VERSION) $(DOCKER_IMAGE_NAME)-$${arch}:latest ;\
	done
endif

.PHONY: docker-push
docker-push:
ifeq ($(DOCKER),)
	$(error "Please specify Docker registry to use. Use DOCKER=coredns for releases")
else
	@# Pushes coredns/coredns-$arch:$version images
	@# Creates manifest for multi-arch image
	@# Pushes multi-arch image to coredns/coredns:$version
	@echo $(DOCKER_PASSWORD) | docker login -u $(DOCKER_LOGIN) --password-stdin
	@echo Pushing: $(VERSION) to $(DOCKER_IMAGE_NAME)
	for arch in $(LINUX_ARCH); do \
		docker push $(DOCKER_IMAGE_NAME)-$${arch}:$(VERSION) ;\
		docker push $(DOCKER_IMAGE_NAME)-$${arch}:latest ;\
	done
	docker manifest create --amend $(DOCKER_IMAGE_NAME):$(VERSION) $(DOCKER_IMAGE_LIST_VERSIONED)
	docker manifest create --amend $(DOCKER_IMAGE_NAME):latest $(DOCKER_IMAGE_LIST_LATEST)
	for arch in $(LINUX_ARCH); do \
		docker manifest annotate --arch $${arch} $(DOCKER_IMAGE_NAME):$(VERSION) $(DOCKER_IMAGE_NAME)-$${arch}:$(VERSION) ;\
		docker manifest annotate --arch $${arch} $(DOCKER_IMAGE_NAME):latest $(DOCKER_IMAGE_NAME)-$${arch}:latest ;\
	done
	docker manifest push --purge $(DOCKER_IMAGE_NAME):$(VERSION)
	docker manifest push --purge $(DOCKER_IMAGE_NAME):latest
endif