Simplify and shrink Dockerfile to use alpine

Add Makefile to simplify the build process.

Signed-off-by: Byron Ruth <b@devel.io>

Dockerfile

@@ -1,10 +1,10 @@
-FROM golang:1.7-onbuild
+FROM alpine:3.5
 
-WORKDIR /
+COPY ./dist/linux-amd64/prometheus-sql /
 
 EXPOSE 8080
 
-ENTRYPOINT ["app", "-host", "0.0.0.0"]
+ENTRYPOINT ["/prometheus-sql", "-host", "0.0.0.0"]
 
 # Default command assumes the SQL agent is linked.
 CMD ["-service", "http://sqlagent:5000"]

Makefile

@@ -0,0 +1,49 @@
+PROG_NAME := "prometheus-sql"
+IMAGE_NAME := "dbhi/prometheus-sql"
+CMD_PATH := "."
+
+GIT_SHA := $(shell git log -1 --pretty=format:"%h" .)
+GIT_TAG := $(shell git describe --tags --exact-match . 2>/dev/null)
+GIT_BRANCH := $(shell git symbolic-ref -q --short HEAD)
+GIT_VERSION := $(shell git log -1 --pretty=format:"%h (%ci)" .)
+
+build:
+	go build -ldflags "-X \"main.buildVersion=$(GIT_VERSION)\"" \
+		-o $(GOPATH)/bin/$(PROG_NAME) $(CMD_PATH)
+
+dist-build:
+	mkdir -p dist
+
+	gox -output="./dist/{{.OS}}-{{.Arch}}/$(PROG_NAME)" \
+		-ldflags "-X \"main.buildVersion=$(GIT_VERSION)\"" \
+		-os "windows linux darwin" \
+		-arch "amd64" $(CMD_PATH) > /dev/null
+
+dist-zip:
+	cd dist && zip $(PROG_NAME)-darwin-amd64.zip darwin-amd64/*
+	cd dist && zip $(PROG_NAME)-linux-amd64.zip linux-amd64/*
+	cd dist && zip $(PROG_NAME)-windows-amd64.zip windows-amd64/*
+
+dist: dist-build dist-zip
+
+docker:
+	docker build -t ${IMAGE_NAME}:${GIT_SHA} .
+	docker tag ${IMAGE_NAME}:${GIT_SHA} ${IMAGE_NAME}:${GIT_BRANCH}
+	if [ -n "${GIT_TAG}" ] ; then \
+		docker tag ${IMAGE_NAME}:${GIT_SHA} ${IMAGE_NAME}:${GIT_TAG} ; \
+	fi;
+	if [ "${GIT_BRANCH}" == "master" ]; then \
+		docker tag ${IMAGE_NAME}:${GIT_SHA} ${IMAGE_NAME}:latest ; \
+	fi;
+
+docker-push:
+	docker push ${IMAGE_NAME}:${GIT_SHA}
+	docker push ${IMAGE_NAME}:${GIT_BRANCH}
+	if [ -n "${GIT_TAG}" ]; then \
+		docker push ${IMAGE_NAME}:${GIT_TAG} ; \
+	fi;
+	if [ "${GIT_BRANCH}" == "master" ]; then \
+		docker push ${IMAGE_NAME}:latest ; \
+	fi;
+
+.PHONY: build dist-build dist