Add version

Makefile

@@ -6,6 +6,8 @@ GOARCH ?= $(shell go env GOARCH)
 GOPKG = github.com/longsleep/realtimetraffic
 GOPATH = "$(CURDIR)/vendor:$(CURDIR)"
 SYSTEM_GOPATH = /usr/share/gocode/src/
+VERSION = $(shell git describe --tags --dirty 2>/dev/null || git rev-parse --short HEAD 2>/dev/null || echo git)
+BUILDSTAMP = $(shell date -u '+%Y-%m-%dT%T%z')
 
 DIST := $(PWD)/dist
 DIST_SRC := $(DIST)/src
@@ -40,7 +42,13 @@ generate-dev:
 	GOPATH=$(GOPATH) $(CURDIR)/vendor/bin/go-bindata -dev -prefix "client/static/" -pkg client -o client/bindata.go client/static/...; fi
 
 binary-%: generate
-	GOPATH=$(GOPATH) GOOS=linux GOARCH=$(GOARCH) GOARM=$(GOARM) CGO_ENABLED=0 go build -ldflags="-s -w" -o bin/realtimetrafficd-$(GOARCH) realtimetrafficd/*.go
+	GOPATH=$(GOPATH) GOOS=linux GOARCH=$(GOARCH) GOARM=$(GOARM) CGO_ENABLED=0 \
+		go build \
+			-ldflags="-s -w \
+				-X main.Version=$(VERSION) \
+				-X main.BuildStamp=$(BUILDSTAMP) \
+			" \
+			-o bin/realtimetrafficd-$(GOARCH) realtimetrafficd/*.go
 
 binary: binary-$(GOARCH)
 	mv bin/realtimetrafficd-$(GOARCH) bin/realtimetrafficd

realtimetrafficd/main.go

@@ -19,16 +19,16 @@ package main
 
 import (
 	"flag"
+	"fmt"
 	"log"
 	"net/http"
+	"runtime"
 
 	"github.com/longsleep/realtimetraffic/client"
 
 	"github.com/gorilla/websocket"
 )
 
-var listenAddr *string
-
 func serveClient(w http.ResponseWriter, r *http.Request) {
 	if r.Method != "GET" && r.Method != "HEAD" {
 		http.Error(w, "Method nod allowed", 405)
@@ -68,15 +68,26 @@ func serveWs(w http.ResponseWriter, r *http.Request) {
 func main() {
 	var err error
 
-	listenAddr = flag.String("listen", "127.0.0.1:8088", "Listen address.")
-
+	listenAddr := flag.String("listen", "127.0.0.1:8088", "Listen address.")
+	versionFlag := flag.Bool("version", false, "Version")
 	flag.Parse()
+
+	if *versionFlag {
+		fmt.Println("Version    :", Version)
+		fmt.Println("Build time :", BuildStamp)
+		fmt.Println("Go         :", runtime.Version())
+		return
+	}
+
 	go h.run()
 	http.HandleFunc("/", serveClient)
 	http.HandleFunc("/realtimetraffic", serveWs)
 
+	log.Printf("starting realtimetrafficd %s on %sn", Version, *listenAddr)
 	err = http.ListenAndServe(*listenAddr, nil)
 	if err != nil {
-		log.Fatal("ListenAndServe: ", err)
+		log.Fatal(err.Error())
 	}
+
+	defer log.Println("exiting")
 }

realtimetrafficd/version.go

@@ -0,0 +1,4 @@
+package main
+
+var Version = "0.0.0"
+var BuildStamp = "not set"