feat(Makefile): add docker build tooling

Still needs a dockerfile

/cc @michelleN

.gitignore

 .coverage/
 bin/
+rootfs/helm
+rootfs/tiller
 vendor/
 _proto/*.pb.go

Makefile

-GO ?= go
+DOCKER_REGISTRY :=
+IMAGE_PREFIX    ?= helm
+SHORT_NAME      ?= tiller
 
+# go option
+GO        ?= go
+GOARCH    ?= $(shell go env GOARCH)
+GOOS      ?= $(shell go env GOOS)
 PKG       := $(shell glide novendor)
 TAGS      :=
 TESTS     := .
 TESTFLAGS :=
 LDFLAGS   :=
+GOFLAGS   :=
+BINDIR    := ./bin
+BINARIES  := helm tiller
 
-BINARIES := helm tiller
+include versioning.mk
 
 .PHONY: all
 all: build
 
 .PHONY: build
+build: GOFLAGS += -v -a -installsuffix cgo
 build:
 	@for i in $(BINARIES); do \
-		$(GO) build -o ./bin/$$i -v $(GOFLAGS) -tags '$(TAGS)' -ldflags '$(LDFLAGS)' ./cmd/$$i || exit 1; \
+		CGO_ENABLED=0 GOOS=$(GOOS) GOARCH=$(GOARCH) $(GO) build -o $(BINDIR)/$$i $(GOFLAGS) -tags '$(TAGS)' -ldflags '$(LDFLAGS)' ./cmd/$$i || exit 1; \
 	done
 
+.PHONY: check-docker
+check-docker:
+	@if [ -z $$(which docker) ]; then \
+	  echo "Missing \`docker\` client which is required for development"; \
+	  exit 2; \
+	fi
+
+.PHONY: docker-binary
+docker-binary: GOOS = linux
+docker-binary: GOARCH = amd64
+docker-binary: BINDIR = ./rootfs
+docker-binary: build
+
+.PHONY: docker-build
+docker-build: check-docker docker-binary
+	docker build --rm -t ${IMAGE} rootfs
+	docker tag -f ${IMAGE} ${MUTABLE_IMAGE}
+
 .PHONY: test
 test: TESTFLAGS += -race -v
 test: test-style
@@ -32,7 +60,7 @@ test-style:
 
 .PHONY: clean
 clean:
-	rm -rf ./bin
+	@rm -rf $(BINDIR)
 
 .PHONY: coverage
 coverage:

rootfs/README.md

+# RootFS
+
+This directory stores all files that should be copied to the rootfs of a
+Docker container. The files should be stored according to the correct
+directory structure of the destination container. For example:
+
+```
+rootfs/bin -> /bin
+rootfs/usr/local/share -> /usr/local/share
+```
+
+## Dockerfile
+
+A Dockerfile in the rootfs is used to build the image. Where possible,
+compilation should not be done in this Dockerfile, since we are
+interested in deploying the smallest possible images.
+
+Example:
+
+```Dockerfile
+FROM alpine:3.2
+
+COPY . /
+
+ENTRYPOINT ["/usr/local/bin/boot"]
+```
+

versioning.mk

+MUTABLE_VERSION ?= canary
+VERSION ?= git-$(shell git rev-parse --short HEAD)
+
+IMAGE := ${DOCKER_REGISTRY}${IMAGE_PREFIX}/${SHORT_NAME}:${VERSION}
+MUTABLE_IMAGE := ${DOCKER_REGISTRY}${IMAGE_PREFIX}/${SHORT_NAME}:${MUTABLE_VERSION}
+
+info:
+	@echo "Build tag:       ${VERSION}"
+	@echo "Registry:        ${DOCKER_REGISTRY}"
+	@echo "Immutable tag:   ${IMAGE}"
+	@echo "Mutable tag:     ${MUTABLE_IMAGE}"
+
+.PHONY: docker-push
+docker-push: docker-mutable-push docker-immutable-push
+
+.PHONY: docker-immutable-push
+docker-immutable-push:
+	docker push ${IMAGE}
+
+.PHONY: docker-mutable-push
+docker-mutable-push:
+	docker push ${MUTABLE_IMAGE}