move port splitting to common place; add to node resource location

pkg/util/port_split.go

@@ -0,0 +1,40 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package util
+
+import (
+	"strings"
+)
+
+// Takes a string of the form "name:port" or "name".
+//  * If id is of the form "name" or "name:", then return (name, "", true)
+//  * If id is of the form "name:port", then return (name, port, true)
+//  * Otherwise, return ("", "", false)
+// Additionally, name must be non-empty or valid will be returned false.
+//
+// Port is returned as a string, and it is not required to be numeric (could be
+// used for a named port, for example).
+func SplitPort(id string) (name, port string, valid bool) {
+	parts := strings.Split(id, ":")
+	if len(parts) > 2 {
+		return "", "", false
+	}
+	if len(parts) == 2 {
+		return parts[0], parts[1], len(parts[0]) > 0
+	}
+	return id, "", len(id) > 0
+}