| // Copyright 2015 The etcd Authors |
| // |
| // 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 flags |
| |
| import ( |
| "errors" |
| "flag" |
| "sort" |
| "strings" |
| ) |
| |
| // NewStringsFlag creates a new string flag for which any one of the given |
| // strings is a valid value, and any other value is an error. |
| // |
| // valids[0] will be default value. Caller must be sure len(valids)!=0 or |
| // it will panic. |
| func NewStringsFlag(valids ...string) *StringsFlag { |
| return &StringsFlag{Values: valids, val: valids[0]} |
| } |
| |
| // StringsFlag implements the flag.Value interface. |
| type StringsFlag struct { |
| Values []string |
| val string |
| } |
| |
| // Set verifies the argument to be a valid member of the allowed values |
| // before setting the underlying flag value. |
| func (ss *StringsFlag) Set(s string) error { |
| for _, v := range ss.Values { |
| if s == v { |
| ss.val = s |
| return nil |
| } |
| } |
| return errors.New("invalid value") |
| } |
| |
| // String returns the set value (if any) of the StringsFlag |
| func (ss *StringsFlag) String() string { |
| return ss.val |
| } |
| |
| // StringsValueV2 wraps "sort.StringSlice". |
| type StringsValueV2 sort.StringSlice |
| |
| // Set parses a command line set of strings, separated by comma. |
| // Implements "flag.Value" interface. |
| func (ss *StringsValueV2) Set(s string) error { |
| *ss = strings.Split(s, ",") |
| return nil |
| } |
| |
| // String implements "flag.Value" interface. |
| func (ss *StringsValueV2) String() string { return strings.Join(*ss, ",") } |
| |
| // NewStringsValueV2 implements string slice as "flag.Value" interface. |
| // Given value is to be separated by comma. |
| func NewStringsValueV2(s string) (ss *StringsValueV2) { |
| if s == "" { |
| return &StringsValueV2{} |
| } |
| ss = new(StringsValueV2) |
| if err := ss.Set(s); err != nil { |
| plog.Panicf("new StringsValueV2 should never fail: %v", err) |
| } |
| return ss |
| } |
| |
| // StringsFromFlagV2 returns a string slice from the flag. |
| func StringsFromFlagV2(fs *flag.FlagSet, flagName string) []string { |
| return []string(*fs.Lookup(flagName).Value.(*StringsValueV2)) |
| } |