Update build system

.dockerignore

@@ -0,0 +1 @@
+.gitignore

Dockerfile

@@ -1,29 +1,21 @@
-FROM golang:1 AS builder
+FROM golang:1.14.4-alpine AS builder
 
-RUN apt-get update && apt-get install -y upx
+RUN apk add --no-cache make git
 
 WORKDIR /build
 
-ENV LD_FLAGS="-w"
-ENV CGO_ENABLED=0
-
 COPY go.mod go.sum /build/
 RUN go mod download
 RUN go mod verify
 
 COPY . /build/
-RUN echo "-- TEST" \
- && go test -cover ./... \
- && echo "-- BUILD" \
- && go install -tags netgo -ldflags "${LD_FLAGS}" . \
- && echo "-- PACK" \
- && upx -9 /go/bin/netatmo-exporter
+RUN make
 
 FROM busybox
 LABEL maintainer="Robert Jacob <xperimental@solidproject.de>"
 
 COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
-COPY --from=builder /go/bin/netatmo-exporter /bin/netatmo-exporter
+COPY --from=builder /build/netatmo-exporter /bin/netatmo-exporter
 
 USER nobody
 EXPOSE 9210

Makefile

@@ -0,0 +1,18 @@
+.PHONY: all test build-binary install clean
+
+GO ?= go
+GO_CMD := CGO_ENABLED=0 $(GO)
+GIT_VERSION := $(shell git describe --tags --dirty)
+VERSION := $(GIT_VERSION:v%=%)
+GIT_COMMIT := $(shell git rev-parse HEAD)
+
+all: test build-binary
+
+test:
+	$(GO_CMD) test -cover ./...
+
+build-binary:
+	$(GO_CMD) build -tags netgo -ldflags "-w -X main.Version=$(VERSION) -X main.GitCommit=$(GIT_COMMIT)" -o netatmo-exporter .
+
+clean:
+	rm -f netatmo-exporter