rclone/vendor/github.com/go-ini/ini/struct.go
2017-07-23 08:51:42 +01:00

499 lines
14 KiB
Go

// Copyright 2014 Unknwon
//
// 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 ini
import (
"bytes"
"errors"
"fmt"
"reflect"
"strings"
"time"
"unicode"
)
// NameMapper represents a ini tag name mapper.
type NameMapper func(string) string
// Built-in name getters.
var (
// AllCapsUnderscore converts to format ALL_CAPS_UNDERSCORE.
AllCapsUnderscore NameMapper = func(raw string) string {
newstr := make([]rune, 0, len(raw))
for i, chr := range raw {
if isUpper := 'A' <= chr && chr <= 'Z'; isUpper {
if i > 0 {
newstr = append(newstr, '_')
}
}
newstr = append(newstr, unicode.ToUpper(chr))
}
return string(newstr)
}
// TitleUnderscore converts to format title_underscore.
TitleUnderscore NameMapper = func(raw string) string {
newstr := make([]rune, 0, len(raw))
for i, chr := range raw {
if isUpper := 'A' <= chr && chr <= 'Z'; isUpper {
if i > 0 {
newstr = append(newstr, '_')
}
chr -= ('A' - 'a')
}
newstr = append(newstr, chr)
}
return string(newstr)
}
)
func (s *Section) parseFieldName(raw, actual string) string {
if len(actual) > 0 {
return actual
}
if s.f.NameMapper != nil {
return s.f.NameMapper(raw)
}
return raw
}
func parseDelim(actual string) string {
if len(actual) > 0 {
return actual
}
return ","
}
var reflectTime = reflect.TypeOf(time.Now()).Kind()
// setSliceWithProperType sets proper values to slice based on its type.
func setSliceWithProperType(key *Key, field reflect.Value, delim string, allowShadow, isStrict bool) error {
var strs []string
if allowShadow {
strs = key.StringsWithShadows(delim)
} else {
strs = key.Strings(delim)
}
numVals := len(strs)
if numVals == 0 {
return nil
}
var vals interface{}
var err error
sliceOf := field.Type().Elem().Kind()
switch sliceOf {
case reflect.String:
vals = strs
case reflect.Int:
vals, err = key.parseInts(strs, true, false)
case reflect.Int64:
vals, err = key.parseInt64s(strs, true, false)
case reflect.Uint:
vals, err = key.parseUints(strs, true, false)
case reflect.Uint64:
vals, err = key.parseUint64s(strs, true, false)
case reflect.Float64:
vals, err = key.parseFloat64s(strs, true, false)
case reflectTime:
vals, err = key.parseTimesFormat(time.RFC3339, strs, true, false)
default:
return fmt.Errorf("unsupported type '[]%s'", sliceOf)
}
if isStrict {
return err
}
slice := reflect.MakeSlice(field.Type(), numVals, numVals)
for i := 0; i < numVals; i++ {
switch sliceOf {
case reflect.String:
slice.Index(i).Set(reflect.ValueOf(vals.([]string)[i]))
case reflect.Int:
slice.Index(i).Set(reflect.ValueOf(vals.([]int)[i]))
case reflect.Int64:
slice.Index(i).Set(reflect.ValueOf(vals.([]int64)[i]))
case reflect.Uint:
slice.Index(i).Set(reflect.ValueOf(vals.([]uint)[i]))
case reflect.Uint64:
slice.Index(i).Set(reflect.ValueOf(vals.([]uint64)[i]))
case reflect.Float64:
slice.Index(i).Set(reflect.ValueOf(vals.([]float64)[i]))
case reflectTime:
slice.Index(i).Set(reflect.ValueOf(vals.([]time.Time)[i]))
}
}
field.Set(slice)
return nil
}
func wrapStrictError(err error, isStrict bool) error {
if isStrict {
return err
}
return nil
}
// setWithProperType sets proper value to field based on its type,
// but it does not return error for failing parsing,
// because we want to use default value that is already assigned to strcut.
func setWithProperType(t reflect.Type, key *Key, field reflect.Value, delim string, allowShadow, isStrict bool) error {
switch t.Kind() {
case reflect.String:
if len(key.String()) == 0 {
return nil
}
field.SetString(key.String())
case reflect.Bool:
boolVal, err := key.Bool()
if err != nil {
return wrapStrictError(err, isStrict)
}
field.SetBool(boolVal)
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
durationVal, err := key.Duration()
// Skip zero value
if err == nil && int(durationVal) > 0 {
field.Set(reflect.ValueOf(durationVal))
return nil
}
intVal, err := key.Int64()
if err != nil {
return wrapStrictError(err, isStrict)
}
field.SetInt(intVal)
// byte is an alias for uint8, so supporting uint8 breaks support for byte
case reflect.Uint, reflect.Uint16, reflect.Uint32, reflect.Uint64:
durationVal, err := key.Duration()
// Skip zero value
if err == nil && int(durationVal) > 0 {
field.Set(reflect.ValueOf(durationVal))
return nil
}
uintVal, err := key.Uint64()
if err != nil {
return wrapStrictError(err, isStrict)
}
field.SetUint(uintVal)
case reflect.Float32, reflect.Float64:
floatVal, err := key.Float64()
if err != nil {
return wrapStrictError(err, isStrict)
}
field.SetFloat(floatVal)
case reflectTime:
timeVal, err := key.Time()
if err != nil {
return wrapStrictError(err, isStrict)
}
field.Set(reflect.ValueOf(timeVal))
case reflect.Slice:
return setSliceWithProperType(key, field, delim, allowShadow, isStrict)
default:
return fmt.Errorf("unsupported type '%s'", t)
}
return nil
}
func parseTagOptions(tag string) (rawName string, omitEmpty bool, allowShadow bool) {
opts := strings.SplitN(tag, ",", 3)
rawName = opts[0]
if len(opts) > 1 {
omitEmpty = opts[1] == "omitempty"
}
if len(opts) > 2 {
allowShadow = opts[2] == "allowshadow"
}
return rawName, omitEmpty, allowShadow
}
func (s *Section) mapTo(val reflect.Value, isStrict bool) error {
if val.Kind() == reflect.Ptr {
val = val.Elem()
}
typ := val.Type()
for i := 0; i < typ.NumField(); i++ {
field := val.Field(i)
tpField := typ.Field(i)
tag := tpField.Tag.Get("ini")
if tag == "-" {
continue
}
rawName, _, allowShadow := parseTagOptions(tag)
fieldName := s.parseFieldName(tpField.Name, rawName)
if len(fieldName) == 0 || !field.CanSet() {
continue
}
isAnonymous := tpField.Type.Kind() == reflect.Ptr && tpField.Anonymous
isStruct := tpField.Type.Kind() == reflect.Struct
if isAnonymous {
field.Set(reflect.New(tpField.Type.Elem()))
}
if isAnonymous || isStruct {
if sec, err := s.f.GetSection(fieldName); err == nil {
if err = sec.mapTo(field, isStrict); err != nil {
return fmt.Errorf("error mapping field(%s): %v", fieldName, err)
}
continue
}
}
if key, err := s.GetKey(fieldName); err == nil {
delim := parseDelim(tpField.Tag.Get("delim"))
if err = setWithProperType(tpField.Type, key, field, delim, allowShadow, isStrict); err != nil {
return fmt.Errorf("error mapping field(%s): %v", fieldName, err)
}
}
}
return nil
}
// MapTo maps section to given struct.
func (s *Section) MapTo(v interface{}) error {
typ := reflect.TypeOf(v)
val := reflect.ValueOf(v)
if typ.Kind() == reflect.Ptr {
typ = typ.Elem()
val = val.Elem()
} else {
return errors.New("cannot map to non-pointer struct")
}
return s.mapTo(val, false)
}
// MapTo maps section to given struct in strict mode,
// which returns all possible error including value parsing error.
func (s *Section) StrictMapTo(v interface{}) error {
typ := reflect.TypeOf(v)
val := reflect.ValueOf(v)
if typ.Kind() == reflect.Ptr {
typ = typ.Elem()
val = val.Elem()
} else {
return errors.New("cannot map to non-pointer struct")
}
return s.mapTo(val, true)
}
// MapTo maps file to given struct.
func (f *File) MapTo(v interface{}) error {
return f.Section("").MapTo(v)
}
// MapTo maps file to given struct in strict mode,
// which returns all possible error including value parsing error.
func (f *File) StrictMapTo(v interface{}) error {
return f.Section("").StrictMapTo(v)
}
// MapTo maps data sources to given struct with name mapper.
func MapToWithMapper(v interface{}, mapper NameMapper, source interface{}, others ...interface{}) error {
cfg, err := Load(source, others...)
if err != nil {
return err
}
cfg.NameMapper = mapper
return cfg.MapTo(v)
}
// StrictMapToWithMapper maps data sources to given struct with name mapper in strict mode,
// which returns all possible error including value parsing error.
func StrictMapToWithMapper(v interface{}, mapper NameMapper, source interface{}, others ...interface{}) error {
cfg, err := Load(source, others...)
if err != nil {
return err
}
cfg.NameMapper = mapper
return cfg.StrictMapTo(v)
}
// MapTo maps data sources to given struct.
func MapTo(v, source interface{}, others ...interface{}) error {
return MapToWithMapper(v, nil, source, others...)
}
// StrictMapTo maps data sources to given struct in strict mode,
// which returns all possible error including value parsing error.
func StrictMapTo(v, source interface{}, others ...interface{}) error {
return StrictMapToWithMapper(v, nil, source, others...)
}
// reflectSliceWithProperType does the opposite thing as setSliceWithProperType.
func reflectSliceWithProperType(key *Key, field reflect.Value, delim string) error {
slice := field.Slice(0, field.Len())
if field.Len() == 0 {
return nil
}
var buf bytes.Buffer
sliceOf := field.Type().Elem().Kind()
for i := 0; i < field.Len(); i++ {
switch sliceOf {
case reflect.String:
buf.WriteString(slice.Index(i).String())
case reflect.Int, reflect.Int64:
buf.WriteString(fmt.Sprint(slice.Index(i).Int()))
case reflect.Uint, reflect.Uint64:
buf.WriteString(fmt.Sprint(slice.Index(i).Uint()))
case reflect.Float64:
buf.WriteString(fmt.Sprint(slice.Index(i).Float()))
case reflectTime:
buf.WriteString(slice.Index(i).Interface().(time.Time).Format(time.RFC3339))
default:
return fmt.Errorf("unsupported type '[]%s'", sliceOf)
}
buf.WriteString(delim)
}
key.SetValue(buf.String()[:buf.Len()-1])
return nil
}
// reflectWithProperType does the opposite thing as setWithProperType.
func reflectWithProperType(t reflect.Type, key *Key, field reflect.Value, delim string) error {
switch t.Kind() {
case reflect.String:
key.SetValue(field.String())
case reflect.Bool:
key.SetValue(fmt.Sprint(field.Bool()))
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
key.SetValue(fmt.Sprint(field.Int()))
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
key.SetValue(fmt.Sprint(field.Uint()))
case reflect.Float32, reflect.Float64:
key.SetValue(fmt.Sprint(field.Float()))
case reflectTime:
key.SetValue(fmt.Sprint(field.Interface().(time.Time).Format(time.RFC3339)))
case reflect.Slice:
return reflectSliceWithProperType(key, field, delim)
default:
return fmt.Errorf("unsupported type '%s'", t)
}
return nil
}
// CR: copied from encoding/json/encode.go with modifications of time.Time support.
// TODO: add more test coverage.
func isEmptyValue(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 reflectTime:
return v.Interface().(time.Time).IsZero()
case reflect.Interface, reflect.Ptr:
return v.IsNil()
}
return false
}
func (s *Section) reflectFrom(val reflect.Value) error {
if val.Kind() == reflect.Ptr {
val = val.Elem()
}
typ := val.Type()
for i := 0; i < typ.NumField(); i++ {
field := val.Field(i)
tpField := typ.Field(i)
tag := tpField.Tag.Get("ini")
if tag == "-" {
continue
}
opts := strings.SplitN(tag, ",", 2)
if len(opts) == 2 && opts[1] == "omitempty" && isEmptyValue(field) {
continue
}
fieldName := s.parseFieldName(tpField.Name, opts[0])
if len(fieldName) == 0 || !field.CanSet() {
continue
}
if (tpField.Type.Kind() == reflect.Ptr && tpField.Anonymous) ||
(tpField.Type.Kind() == reflect.Struct && tpField.Type.Name() != "Time") {
// Note: The only error here is section doesn't exist.
sec, err := s.f.GetSection(fieldName)
if err != nil {
// Note: fieldName can never be empty here, ignore error.
sec, _ = s.f.NewSection(fieldName)
}
if err = sec.reflectFrom(field); err != nil {
return fmt.Errorf("error reflecting field (%s): %v", fieldName, err)
}
continue
}
// Note: Same reason as secion.
key, err := s.GetKey(fieldName)
if err != nil {
key, _ = s.NewKey(fieldName, "")
}
if err = reflectWithProperType(tpField.Type, key, field, parseDelim(tpField.Tag.Get("delim"))); err != nil {
return fmt.Errorf("error reflecting field (%s): %v", fieldName, err)
}
}
return nil
}
// ReflectFrom reflects secion from given struct.
func (s *Section) ReflectFrom(v interface{}) error {
typ := reflect.TypeOf(v)
val := reflect.ValueOf(v)
if typ.Kind() == reflect.Ptr {
typ = typ.Elem()
val = val.Elem()
} else {
return errors.New("cannot reflect from non-pointer struct")
}
return s.reflectFrom(val)
}
// ReflectFrom reflects file from given struct.
func (f *File) ReflectFrom(v interface{}) error {
return f.Section("").ReflectFrom(v)
}
// ReflectFrom reflects data sources from given struct with name mapper.
func ReflectFromWithMapper(cfg *File, v interface{}, mapper NameMapper) error {
cfg.NameMapper = mapper
return cfg.ReflectFrom(v)
}
// ReflectFrom reflects data sources from given struct.
func ReflectFrom(cfg *File, v interface{}) error {
return ReflectFromWithMapper(cfg, v, nil)
}