Extend Makefile for selecting architecture

Makefile

@@ -1,6 +1,8 @@
 .PHONY: all test build-binary install clean
 
 GO ?= go
+GO_OS ?= linux
+GO_ARCH ?= amd64
 GO_CMD := CGO_ENABLED=0 $(GO)
 GIT_VERSION := $(shell git describe --tags --dirty)
 VERSION := $(GIT_VERSION:v%=%)
@@ -12,7 +14,7 @@ test:
 	$(GO_CMD) test -cover ./...
 
 build-binary:
-	$(GO_CMD) build -tags netgo -ldflags "-w -X main.Version=$(VERSION) -X main.GitCommit=$(GIT_COMMIT)" -o netatmo-exporter .
+	GOOS=$(GO_OS) GOARCH=$(GO_ARCH) $(GO_CMD) build -tags netgo -ldflags "-w -X main.Version=$(VERSION) -X main.GitCommit=$(GIT_COMMIT)" -o netatmo-exporter .
 
 clean:
 	rm -f netatmo-exporter

README.md

@@ -19,14 +19,21 @@ If you have a working Go installation, getting the binary should be as simple as
 ```bash
 git clone https://github.com/xperimental/netatmo-exporter
 cd netatmo-exporter
-go build .
+make
 ```
 
-There is also a `build-arm.sh` script if you want to run the exporter on an ARMv7 device.
+If you want to build the exporter for a different OS or architecture, you can specify arguments to the Makefile:
+
+```bash
+# For 32-bit ARM on Linux
+make GO_ARCH=arm
+# For 64-bit ARM on Linux
+make GO_ARCH=arm64
+```
 
 ## NetAtmo client credentials
 
-This application tries to get data from the NetAtmo API. For that to work you will need to create an application in the [NetAtmo developer console](https://dev.netatmo.com/dev/myaccount), so that you can get a Client ID and secret.
+This application tries to get data from the NetAtmo API. For that to work you will need to create an application in the [NetAtmo developer console](https://dev.netatmo.com/apps/), so that you can get a Client ID and secret.
 
 ## Usage
 

build-arm.sh

@@ -1,9 +0,0 @@
-#!/bin/bash -e
-
-echo "Build binary..."
-GOOS=linux GOARCH=arm go build -v -ldflags="-s -w" .
-
-type upx && {
-    echo "Packing using upx..."
-    upx -9 netatmo-exporter
-} || echo "upx not available"