120 lines
2.8 KiB
Go
120 lines
2.8 KiB
Go
/*
|
||
* Copyright (c) 2020 Alex aka mailoman <alex@webz.asia>
|
||
*
|
||
* 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.
|
||
*
|
||
* @author Alex aka mailoman <alex@webz.asia>
|
||
* @copyright Copyright (c) 2020 Alex aka mailoman <alex@webz.asia>
|
||
* @since 14.01.2020
|
||
*
|
||
*/
|
||
|
||
package fields
|
||
|
||
import (
|
||
"log"
|
||
"reflect"
|
||
"strings"
|
||
|
||
"github.com/satori/go.uuid"
|
||
)
|
||
|
||
//Convert copies field values from one struct to another based on tags setup
|
||
func Сonvert(from interface{}, kind string, to interface{}) {
|
||
if nil == from {
|
||
log.Print("nil value is not supported")
|
||
|
||
return
|
||
}
|
||
|
||
v := reflect.ValueOf(from)
|
||
vt := reflect.ValueOf(to)
|
||
t := v.Type()
|
||
|
||
if t.Kind() != reflect.Struct {
|
||
log.Printf("type %s is not supported", t.Kind())
|
||
|
||
return
|
||
}
|
||
|
||
if vt.Kind() == reflect.Ptr {
|
||
vt = reflect.ValueOf(to).Elem()
|
||
}
|
||
|
||
for i := 0; i < t.NumField(); i++ {
|
||
f := t.Field(i)
|
||
// skip unexported fields. from godoc:
|
||
// PkgPath is the package path that qualifies a lower case (unexported)
|
||
// field name. It is empty for upper case (exported) field names.
|
||
if f.PkgPath != "" && f.Name == "" {
|
||
continue
|
||
}
|
||
fv := v.Field(i)
|
||
found, omit, omitempty := readTag(f, kind)
|
||
// skip if tag "omit" set.
|
||
if omit {
|
||
continue
|
||
}
|
||
// skip empty values when "omitempty" set.
|
||
if omitempty && fv.String() == "" {
|
||
continue
|
||
}
|
||
|
||
if found {
|
||
ft := vt.FieldByName(f.Name)
|
||
if f.Name == strings.ToUpper(f.Name) && !ft.IsValid() {
|
||
// was uppercase and not valid => to Capitalize first letter
|
||
ft = vt.FieldByName(strings.Title(strings.ToLower(f.Name)))
|
||
}
|
||
|
||
if !ft.IsValid() && fv.Kind() == reflect.Struct {
|
||
Сonvert(fv.Interface(), kind, to)
|
||
} else {
|
||
if ft.IsValid() {
|
||
switch f.Type.String() {
|
||
case "uuid.UUID":
|
||
mv := fv.Interface().(uuid.UUID)
|
||
if ft.Type().String() == "uuid.UUID" {
|
||
ft.Set(fv)
|
||
} else {
|
||
ft.SetString(mv.String())
|
||
}
|
||
default:
|
||
ft.Set(fv)
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
func readTag(f reflect.StructField, kind string) (bool, bool, bool) {
|
||
val, ok := f.Tag.Lookup(ConvertTagName())
|
||
if !ok {
|
||
return false, false, false
|
||
}
|
||
opts := strings.Split(val, ",")
|
||
|
||
return indexOf(opts, kind) > -1, indexOf(opts, OmitTagName()) > -1, indexOf(opts, OmitEmptyTagName()) > -1
|
||
}
|
||
|
||
func indexOf(a []string, x string) int {
|
||
for i, n := range a {
|
||
if x == n {
|
||
return i
|
||
}
|
||
}
|
||
|
||
return -1
|
||
}
|