1// Copyright 2018 The etcd Authors 2// 3// Licensed under the Apache License, Version 2.0 (the "License"); 4// you may not use this file except in compliance with the License. 5// You may obtain a copy of the License at 6// 7// http://www.apache.org/licenses/LICENSE-2.0 8// 9// Unless required by applicable law or agreed to in writing, software 10// distributed under the License is distributed on an "AS IS" BASIS, 11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12// See the License for the specific language governing permissions and 13// limitations under the License. 14 15package flags 16 17import ( 18 "flag" 19 "sort" 20 "strings" 21) 22 23// StringsValue wraps "sort.StringSlice". 24type StringsValue sort.StringSlice 25 26// Set parses a command line set of strings, separated by comma. 27// Implements "flag.Value" interface. 28func (ss *StringsValue) Set(s string) error { 29 *ss = strings.Split(s, ",") 30 return nil 31} 32 33// String implements "flag.Value" interface. 34func (ss *StringsValue) String() string { return strings.Join(*ss, ",") } 35 36// NewStringsValue implements string slice as "flag.Value" interface. 37// Given value is to be separated by comma. 38func NewStringsValue(s string) (ss *StringsValue) { 39 if s == "" { 40 return &StringsValue{} 41 } 42 ss = new(StringsValue) 43 if err := ss.Set(s); err != nil { 44 plog.Panicf("new StringsValue should never fail: %v", err) 45 } 46 return ss 47} 48 49// StringsFromFlag returns a string slice from the flag. 50func StringsFromFlag(fs *flag.FlagSet, flagName string) []string { 51 return []string(*fs.Lookup(flagName).Value.(*StringsValue)) 52} 53