khenaidoo | ffe076b | 2019-01-15 16:08:08 -0500 | [diff] [blame^] | 1 | // Copyright 2015 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 | |
| 15 | package flags |
| 16 | |
| 17 | import ( |
| 18 | "errors" |
| 19 | "flag" |
| 20 | "sort" |
| 21 | "strings" |
| 22 | ) |
| 23 | |
| 24 | // NewStringsFlag creates a new string flag for which any one of the given |
| 25 | // strings is a valid value, and any other value is an error. |
| 26 | // |
| 27 | // valids[0] will be default value. Caller must be sure len(valids)!=0 or |
| 28 | // it will panic. |
| 29 | func NewStringsFlag(valids ...string) *StringsFlag { |
| 30 | return &StringsFlag{Values: valids, val: valids[0]} |
| 31 | } |
| 32 | |
| 33 | // StringsFlag implements the flag.Value interface. |
| 34 | type StringsFlag struct { |
| 35 | Values []string |
| 36 | val string |
| 37 | } |
| 38 | |
| 39 | // Set verifies the argument to be a valid member of the allowed values |
| 40 | // before setting the underlying flag value. |
| 41 | func (ss *StringsFlag) Set(s string) error { |
| 42 | for _, v := range ss.Values { |
| 43 | if s == v { |
| 44 | ss.val = s |
| 45 | return nil |
| 46 | } |
| 47 | } |
| 48 | return errors.New("invalid value") |
| 49 | } |
| 50 | |
| 51 | // String returns the set value (if any) of the StringsFlag |
| 52 | func (ss *StringsFlag) String() string { |
| 53 | return ss.val |
| 54 | } |
| 55 | |
| 56 | // StringsValueV2 wraps "sort.StringSlice". |
| 57 | type StringsValueV2 sort.StringSlice |
| 58 | |
| 59 | // Set parses a command line set of strings, separated by comma. |
| 60 | // Implements "flag.Value" interface. |
| 61 | func (ss *StringsValueV2) Set(s string) error { |
| 62 | *ss = strings.Split(s, ",") |
| 63 | return nil |
| 64 | } |
| 65 | |
| 66 | // String implements "flag.Value" interface. |
| 67 | func (ss *StringsValueV2) String() string { return strings.Join(*ss, ",") } |
| 68 | |
| 69 | // NewStringsValueV2 implements string slice as "flag.Value" interface. |
| 70 | // Given value is to be separated by comma. |
| 71 | func NewStringsValueV2(s string) (ss *StringsValueV2) { |
| 72 | if s == "" { |
| 73 | return &StringsValueV2{} |
| 74 | } |
| 75 | ss = new(StringsValueV2) |
| 76 | if err := ss.Set(s); err != nil { |
| 77 | plog.Panicf("new StringsValueV2 should never fail: %v", err) |
| 78 | } |
| 79 | return ss |
| 80 | } |
| 81 | |
| 82 | // StringsFromFlagV2 returns a string slice from the flag. |
| 83 | func StringsFromFlagV2(fs *flag.FlagSet, flagName string) []string { |
| 84 | return []string(*fs.Lookup(flagName).Value.(*StringsValueV2)) |
| 85 | } |