optimize the perf and support more features

cmd/create.go

@@ -86,6 +86,9 @@ func createTarget(cli *client.Client, opts api.TargetCreateRequest) error {
 	if err != nil {
 		return err
 	}
+	if tgt == nil {
+		return fmt.Errorf("target creation returned nil")
+	}
 	fmt.Printf("Target %s successfully created\n", tgt.Name)
 	return nil
 }

cmd/daemon.go

@@ -63,18 +63,11 @@ func newDaemonCommand() *cobra.Command {
 }
 
 func createDaemon(host, driver, level string, blockMultipleHosts bool, port int) error {
-	switch level {
-	case "info":
-		log.SetLevel(log.InfoLevel)
-	case "warn":
-		log.SetLevel(log.WarnLevel)
-	case "debug":
-		log.SetLevel(log.DebugLevel)
-	case "panic", "fatal", "error":
-		log.SetLevel(log.ErrorLevel)
-	default:
-		return fmt.Errorf("unknown log level: %v", level)
+	logLevel, err := log.ParseLevel(level)
+	if err != nil {
+		return fmt.Errorf("invalid log level %q: %w", level, err)
 	}
+	log.SetLevel(logLevel)
 	config, err := config.Load(config.ConfigDir())
 	if err != nil {
 		log.Error(err)

cmd/list.go

@@ -93,6 +93,9 @@ func listTarget(cli *client.Client, opts api.TargetListOptions) error {
 	w := tabwriter.NewWriter(os.Stdout, 20, 1, 3, ' ', 0)
 	fmt.Fprintln(w, "TARGET NAME\tSTATE\tSESSIONS")
 	for _, tgt := range results {
+		if tgt == nil {
+			continue
+		}
 		status := "online"
 		if tgt.State == api.TargetReady {
 			status = "ready"