Merge pull request #750 from weaveworks/749-version

Rationalise version handling

docker/entrypoint.sh

@@ -68,6 +68,11 @@ mkdir -p /etc/weave
 APP_ARGS=""
 PROBE_ARGS=""
 
+if [ "$1" = version ]; then
+    /home/weave/scope version
+    exit 0
+fi
+
 while true; do
     case "$1" in
         --app.*)

prog/app.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"flag"
-	"fmt"
 	"log"
 	"math/rand"
 	"net/http"
@@ -32,18 +31,12 @@ func router(c app.Collector) *mux.Router {
 // Main runs the app
 func appMain() {
 	var (
-		window       = flag.Duration("window", 15*time.Second, "window")
-		listen       = flag.String("http.address", ":"+strconv.Itoa(xfer.AppPort), "webserver listen address")
-		logPrefix    = flag.String("log.prefix", "<app>", "prefix for each log line")
-		printVersion = flag.Bool("version", false, "print version number and exit")
+		window    = flag.Duration("window", 15*time.Second, "window")
+		listen    = flag.String("http.address", ":"+strconv.Itoa(xfer.AppPort), "webserver listen address")
+		logPrefix = flag.String("log.prefix", "<app>", "prefix for each log line")
 	)
 	flag.Parse()
 
-	if *printVersion {
-		fmt.Println(app.Version)
-		return
-	}
-
 	if !strings.HasSuffix(*logPrefix, " ") {
 		*logPrefix += " "
 	}
@@ -53,6 +46,7 @@ func appMain() {
 
 	rand.Seed(time.Now().UnixNano())
 	app.UniqueID = strconv.FormatInt(rand.Int63(), 16)
+	app.Version = version
 	log.Printf("app starting, version %s, ID %s", app.Version, app.UniqueID)
 	http.Handle("/", router(app.NewCollector(*window)))
 	go func() {

prog/main.go

@@ -5,8 +5,10 @@ import (
 	"os"
 )
 
+var version = "dev" // set at build time
+
 func usage() {
-	fmt.Fprintf(os.Stderr, "usage: %s (app|probe) args...\n", os.Args[0])
+	fmt.Fprintf(os.Stderr, "usage: %s (app|probe|version) args...\n", os.Args[0])
 	os.Exit(1)
 }
 
@@ -23,6 +25,8 @@ func main() {
 		appMain()
 	case "probe":
 		probeMain()
+	case "version":
+		fmt.Println("Weave Scope version", version)
 	default:
 		usage()
 	}

prog/probe.go

@@ -29,8 +29,6 @@ import (
 	"github.com/weaveworks/scope/xfer"
 )
 
-var version = "dev" // set at build time
-
 // Main runs the probe
 func probeMain() {
 	var (
@@ -48,18 +46,12 @@ func probeMain() {
 		kubernetesInterval = flag.Duration("kubernetes.interval", 10*time.Second, "how often to do a full resync of the kubernetes data")
 		weaveRouterAddr    = flag.String("weave.router.addr", "", "IP address or FQDN of the Weave router")
 		procRoot           = flag.String("proc.root", "/proc", "location of the proc filesystem")
-		printVersion       = flag.Bool("version", false, "print version number and exit")
 		useConntrack       = flag.Bool("conntrack", true, "also use conntrack to track connections")
 		insecure           = flag.Bool("insecure", false, "(SSL) explicitly allow \"insecure\" SSL connections and transfers")
 		logPrefix          = flag.String("log.prefix", "<probe>", "prefix for each log line")
 	)
 	flag.Parse()
 
-	if *printVersion {
-		fmt.Println(version)
-		return
-	}
-
 	// Setup in memory metrics sink
 	inm := metrics.NewInmemSink(time.Minute, 2*time.Minute)
 	sig := metrics.DefaultInmemSignal(inm)

scope

@@ -102,6 +102,10 @@ case "$COMMAND" in
         launch_command "$@"
         ;;
 
+    version)
+        docker run $SCOPE_IMAGE version
+        ;;
+
     launch)
         check_not_running $SCOPE_CONTAINER_NAME $SCOPE_IMAGE_NAME
         docker rm -f $SCOPE_CONTAINER_NAME >/dev/null 2>&1 || true