.PHONY: tag push BASE=debian:jessie IMAGE=guestfs default: push hash: Dockerfile DOCKER_CONTENT_TRUST=1 docker pull $(BASE) tar cf - $^ | docker build --no-cache -t $(IMAGE):build - docker run --rm $(IMAGE):build sh -c 'apt list --installed 2>/dev/null | sha1sum' | sed 's/ .*//' > hash push: hash docker pull linuxkit/$(IMAGE):$(shell cat hash) || \ (docker tag $(IMAGE):build linuxkit/$(IMAGE):$(shell cat hash) && \ docker push linuxkit/$(IMAGE):$(shell cat hash)) docker rmi $(IMAGE):build rm -f hash tag: hash docker pull linuxkit/$(IMAGE):$(shell cat hash) || \ docker tag $(IMAGE):build linuxkit/$(IMAGE):$(shell cat hash) docker rmi $(IMAGE):build rm -f hash clean: rm -f hash .DELETE_ON_ERROR: