| /* |
| Copyright 2019 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 value |
| |
| import ( |
| "fmt" |
| "reflect" |
| "strings" |
| ) |
| |
| // TODO: This implements the same functionality as https://github.com/kubernetes/kubernetes/blob/master/staging/src/k8s.io/apimachinery/pkg/runtime/converter.go#L236 |
| // but is based on the highly efficient approach from https://golang.org/src/encoding/json/encode.go |
| |
| func lookupJsonTags(f reflect.StructField) (name string, omit bool, inline bool, omitempty bool) { |
| tag := f.Tag.Get("json") |
| if tag == "-" { |
| return "", true, false, false |
| } |
| name, opts := parseTag(tag) |
| if name == "" { |
| name = f.Name |
| } |
| return name, false, opts.Contains("inline"), opts.Contains("omitempty") |
| } |
| |
| func isZero(v reflect.Value) bool { |
| switch v.Kind() { |
| case reflect.Array, reflect.Map, reflect.Slice, reflect.String: |
| return v.Len() == 0 |
| case reflect.Bool: |
| return !v.Bool() |
| case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: |
| return v.Int() == 0 |
| case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: |
| return v.Uint() == 0 |
| case reflect.Float32, reflect.Float64: |
| return v.Float() == 0 |
| case reflect.Interface, reflect.Ptr: |
| return v.IsNil() |
| case reflect.Chan, reflect.Func: |
| panic(fmt.Sprintf("unsupported type: %v", v.Type())) |
| } |
| return false |
| } |
| |
| type tagOptions string |
| |
| // parseTag splits a struct field's json tag into its name and |
| // comma-separated options. |
| func parseTag(tag string) (string, tagOptions) { |
| if idx := strings.Index(tag, ","); idx != -1 { |
| return tag[:idx], tagOptions(tag[idx+1:]) |
| } |
| return tag, tagOptions("") |
| } |
| |
| // Contains reports whether a comma-separated list of options |
| // contains a particular substr flag. substr must be surrounded by a |
| // string boundary or commas. |
| func (o tagOptions) Contains(optionName string) bool { |
| if len(o) == 0 { |
| return false |
| } |
| s := string(o) |
| for s != "" { |
| var next string |
| i := strings.Index(s, ",") |
| if i >= 0 { |
| s, next = s[:i], s[i+1:] |
| } |
| if s == optionName { |
| return true |
| } |
| s = next |
| } |
| return false |
| } |