| /* |
| Copyright 2017 The Kubernetes 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 flag |
| |
| import ( |
| "fmt" |
| "sort" |
| "strings" |
| ) |
| |
| // ColonSeparatedMultimapStringString supports setting a map[string][]string from an encoding |
| // that separates keys from values with ':' and separates key-value pairs with ','. |
| // A key can be repeated multiple times, in which case the values are appended to a |
| // slice of strings associated with that key. Items in the list associated with a given |
| // key will appear in the order provided. |
| // For example: `a:hello,b:again,c:world,b:beautiful` results in `{"a": ["hello"], "b": ["again", "beautiful"], "c": ["world"]}` |
| // The first call to Set will clear the map before adding entries; subsequent calls will simply append to the map. |
| // This makes it possible to override default values with a command-line option rather than appending to defaults, |
| // while still allowing the distribution of key-value pairs across multiple flag invocations. |
| // For example: `--flag "a:hello" --flag "b:again" --flag "b:beautiful" --flag "c:world"` results in `{"a": ["hello"], "b": ["again", "beautiful"], "c": ["world"]}` |
| type ColonSeparatedMultimapStringString struct { |
| Multimap *map[string][]string |
| initialized bool // set to true after the first Set call |
| } |
| |
| // NewColonSeparatedMultimapStringString takes a pointer to a map[string][]string and returns the |
| // ColonSeparatedMultimapStringString flag parsing shim for that map. |
| func NewColonSeparatedMultimapStringString(m *map[string][]string) *ColonSeparatedMultimapStringString { |
| return &ColonSeparatedMultimapStringString{Multimap: m} |
| } |
| |
| // Set implements github.com/spf13/pflag.Value |
| func (m *ColonSeparatedMultimapStringString) Set(value string) error { |
| if m.Multimap == nil { |
| return fmt.Errorf("no target (nil pointer to map[string][]string)") |
| } |
| if !m.initialized || *m.Multimap == nil { |
| // clear default values, or allocate if no existing map |
| *m.Multimap = make(map[string][]string) |
| m.initialized = true |
| } |
| for _, pair := range strings.Split(value, ",") { |
| if len(pair) == 0 { |
| continue |
| } |
| kv := strings.SplitN(pair, ":", 2) |
| if len(kv) != 2 { |
| return fmt.Errorf("malformed pair, expect string:string") |
| } |
| k := strings.TrimSpace(kv[0]) |
| v := strings.TrimSpace(kv[1]) |
| (*m.Multimap)[k] = append((*m.Multimap)[k], v) |
| } |
| return nil |
| } |
| |
| // String implements github.com/spf13/pflag.Value |
| func (m *ColonSeparatedMultimapStringString) String() string { |
| type kv struct { |
| k string |
| v string |
| } |
| kvs := make([]kv, 0, len(*m.Multimap)) |
| for k, vs := range *m.Multimap { |
| for i := range vs { |
| kvs = append(kvs, kv{k: k, v: vs[i]}) |
| } |
| } |
| // stable sort by keys, order of values should be preserved |
| sort.SliceStable(kvs, func(i, j int) bool { |
| return kvs[i].k < kvs[j].k |
| }) |
| pairs := make([]string, 0, len(kvs)) |
| for i := range kvs { |
| pairs = append(pairs, fmt.Sprintf("%s:%s", kvs[i].k, kvs[i].v)) |
| } |
| return strings.Join(pairs, ",") |
| } |
| |
| // Type implements github.com/spf13/pflag.Value |
| func (m *ColonSeparatedMultimapStringString) Type() string { |
| return "colonSeparatedMultimapStringString" |
| } |
| |
| // Empty implements OmitEmpty |
| func (m *ColonSeparatedMultimapStringString) Empty() bool { |
| return len(*m.Multimap) == 0 |
| } |