Add support for znode flag

README.md

@@ -14,6 +14,7 @@ Name                            | Description
 web.listen-address              | Address to listen on for web interface and telemetry.
 web.telemetry-path              | Path under which to expose metrics.
 exporter.aurora-url             | [URL](#aurora-url) to an Aurora scheduler or ZooKeeper ensemble.
+zk.path                         | The path for the aurora scheduler znode, this defaults to `/aurora/scheduler`
 exporter.bypass-leader-redirect | Don't follow redirects to the leader instance.
 
 #### Aurora URL

finder.go

@@ -14,22 +14,20 @@ import (
 	"github.com/samuel/go-zookeeper/zk"
 )
 
-const (
-	zkPath         = "/aurora/scheduler"
-	zkLeaderPrefix = "singleton_candidate_"
-)
+const zkLeaderPrefix = "singleton_candidate_"
+
 
 type finder interface {
 	leaderURL() (string, error)
 }
 
-func newFinder(url string) (f finder, err error) {
+func newFinder(url, znode string) (f finder, err error) {
 	if strings.HasPrefix(url, "http") {
 		f = &httpFinder{url: url}
 	}
 
 	if strings.HasPrefix(url, "zk://") {
-		f = newZkFinder(url)
+		f = newZkFinder(url, znode)
 	}
 
 	if f == nil {
@@ -86,7 +84,7 @@ type zkFinder struct {
 	leaderIP string
 }
 
-func newZkFinder(url string) *zkFinder {
+func newZkFinder(url, znode string) *zkFinder {
 	zkSrvs, err := hostsFromURL(url)
 	if err != nil {
 		panic(err)
@@ -104,12 +102,12 @@ func newZkFinder(url string) *zkFinder {
 	}()
 
 	f := zkFinder{conn: conn}
-	go f.watch()
+	go f.watch(znode)
 
 	return &f
 }
 
-func (f *zkFinder) leaderzNode() (string, error) {
+func (f *zkFinder) leaderzNode(zkPath string) (string, error) {
 	children, stat, err := f.conn.Children(zkPath)
 	if stat == nil {
 		err = errors.New("zkFinder: children returned nil stat")
@@ -157,9 +155,9 @@ func (f *zkFinder) leaderURL() (string, error) {
 	return fmt.Sprintf("http://%s:8081", f.leaderIP), nil
 }
 
-func (f *zkFinder) watch() {
+func (f *zkFinder) watch(znode string) {
 	for _ = range time.NewTicker(1 * time.Second).C {
-		zNode, err := f.leaderzNode()
+		zNode, err := f.leaderzNode(znode)
 		if err != nil {
 			glog.Warning(err)
 			continue

main.go

@@ -21,6 +21,7 @@ var (
 	addr           = flag.String("web.listen-address", ":9113", "Address to listen on for web interface and telemetry.")
 	auroraURL      = flag.String("exporter.aurora-url", "http://127.0.0.1:8081", "URL to an Aurora scheduler or ZooKeeper ensemble")
 	metricPath     = flag.String("web.telemetry-path", "/metrics", "Path under which to expose metrics.")
+	zkPath     = flag.String("zk.path", "/aurora/scheduler", "zkNode that aurora maintains master election.")
 	bypassRedirect = flag.Bool("exporter.bypass-leader-redirect", false,
 		"When scraping a HTTP scheduler url, don't follow redirects to the leader instance.")
 )
@@ -220,7 +221,7 @@ func newRequest(method, urlStr string, body io.Reader, bypass bool) (*http.Reque
 func main() {
 	flag.Parse()
 
-	finder, err := newFinder(*auroraURL)
+	finder, err := newFinder(*auroraURL, *zkPath)
 	if err != nil {
 		log.Fatal(err)
 	}