Add functionality to bind custom IP address for Etcd metrics endpoint (#2750)

* Add functionality to bind custom IP address for Etcd metrics endpoint

Signed-off-by: yuriydzobak <yurii.dzobak@lotusflare.com>

pkg/cli/cmds/server.go

@@ -60,6 +60,7 @@ type Server struct {
 	StartupHooks             []func(context.Context, <-chan struct{}, string) error
 	EtcdSnapshotName         string
 	EtcdDisableSnapshots     bool
+	EtcdExposeMetrics        bool
 	EtcdSnapshotDir          string
 	EtcdSnapshotCron         string
 	EtcdSnapshotRetention    int
@@ -210,6 +211,11 @@ func NewServerCommand(action func(*cli.Context) error) cli.Command {
 				Destination: &ServerConfig.DatastoreKeyFile,
 				EnvVar:      version.ProgramUpper + "_DATASTORE_KEYFILE",
 			},
+			&cli.BoolFlag{
+				Name:        "etcd-expose-metrics",
+				Usage:       "(db) Expose etcd metrics to client interface. (Default false)",
+				Destination: &ServerConfig.EtcdExposeMetrics,
+			},
 			&cli.BoolFlag{
 				Name:        "etcd-disable-snapshots",
 				Usage:       "(db) Disable automatic etcd snapshots",

pkg/cli/server/server.go

@@ -116,6 +116,7 @@ func run(app *cli.Context, cfg *cmds.Server) error {
 	serverConfig.ControlConfig.EtcdSnapshotDir = cfg.EtcdSnapshotDir
 	serverConfig.ControlConfig.EtcdSnapshotRetention = cfg.EtcdSnapshotRetention
 	serverConfig.ControlConfig.EtcdDisableSnapshots = cfg.EtcdDisableSnapshots
+	serverConfig.ControlConfig.EtcdExposeMetrics = cfg.EtcdExposeMetrics
 
 	if cfg.ClusterResetRestorePath != "" && !cfg.ClusterReset {
 		return errors.New("Invalid flag use. --cluster-reset required with --cluster-reset-restore-path")

pkg/daemons/config/types.go

@@ -132,6 +132,7 @@ type Control struct {
 	TLSCipherSuites          []uint16
 	EtcdSnapshotName         string
 	EtcdDisableSnapshots     bool
+	EtcdExposeMetrics        bool
 	EtcdSnapshotDir          string
 	EtcdSnapshotCron         string
 	EtcdSnapshotRetention    int

pkg/etcd/etcd.go

@@ -482,6 +482,14 @@ func (e *ETCD) clientURL() string {
 	return fmt.Sprintf("https://%s:2379", e.address)
 }
 
+// metricsURL returns the metrics access address
+func (e *ETCD) metricsURL(expose bool) string {
+	if expose {
+		return fmt.Sprintf("http://%s:2381", e.address)
+	}
+	return "http://127.0.0.1:2381"
+}
+
 // cluster returns ETCDConfig for a cluster
 func (e *ETCD) cluster(ctx context.Context, forceNew bool, options executor.InitialOptions) error {
 	return executor.ETCD(executor.ETCDConfig{
@@ -489,7 +497,7 @@ func (e *ETCD) cluster(ctx context.Context, forceNew bool, options executor.Init
 		InitialOptions:      options,
 		ForceNewCluster:     forceNew,
 		ListenClientURLs:    fmt.Sprintf(e.clientURL() + ",https://127.0.0.1:2379"),
-		ListenMetricsURLs:   "http://127.0.0.1:2381",
+		ListenMetricsURLs:   e.metricsURL(e.config.EtcdExposeMetrics),
 		ListenPeerURLs:      e.peerURL(),
 		AdvertiseClientURLs: e.clientURL(),
 		DataDir:             etcdDBDir(e.config),