service/vendor/github.com/clbanning/mxj/v2/rename.go

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2023-12-21 22:17:40 +08:00
package mxj
import (
"errors"
"strings"
)
// RenameKey renames a key in a Map.
// It works only for nested maps.
// It doesn't work for cases when the key is in a list.
func (mv Map) RenameKey(path string, newName string) error {
var v bool
var err error
if v, err = mv.Exists(path); err == nil && !v {
return errors.New("RenameKey: path not found: " + path)
} else if err != nil {
return err
}
if v, err = mv.Exists(parentPath(path) + "." + newName); err == nil && v {
return errors.New("RenameKey: key already exists: " + newName)
} else if err != nil {
return err
}
m := map[string]interface{}(mv)
return renameKey(m, path, newName)
}
func renameKey(m interface{}, path string, newName string) error {
val, err := prevValueByPath(m, path)
if err != nil {
return err
}
oldName := lastKey(path)
val[newName] = val[oldName]
delete(val, oldName)
return nil
}
// returns a value which contains a last key in the path
// For example: prevValueByPath("a.b.c", {a{b{c: 3}}}) returns {c: 3}
func prevValueByPath(m interface{}, path string) (map[string]interface{}, error) {
keys := strings.Split(path, ".")
switch mValue := m.(type) {
case map[string]interface{}:
for key, value := range mValue {
if key == keys[0] {
if len(keys) == 1 {
return mValue, nil
} else {
// keep looking for the full path to the key
return prevValueByPath(value, strings.Join(keys[1:], "."))
}
}
}
}
return nil, errors.New("prevValueByPath: didn't find path " + path)
}