{{ message }}
Repository navigation
Expand file tree
/
Copy pathmapstructure.go
More file actions
1542 lines (1336 loc) · 43.9 KB
/
Copy pathmapstructure.go
File metadata and controls
1542 lines (1336 loc) · 43.9 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// Package mapstructure exposes functionality to convert one arbitrary
// Go type into another, typically to convert a map[string]interface{}
// into a native Go structure.
//
// The Go structure can be arbitrarily complex, containing slices,
// other structs, etc. and the decoder will properly decode nested
// maps and so on into the proper structures in the native Go struct.
// See the examples to see what the decoder is capable of.
//
// The simplest function to start with is Decode.
//
// # Field Tags
//
// When decoding to a struct, mapstructure will use the field name by
// default to perform the mapping. For example, if a struct has a field
// "Username" then mapstructure will look for a key in the source value
// of "username" (case insensitive).
//
// type User struct {
// Username string
// }
//
// You can change the behavior of mapstructure by using struct tags.
// The default struct tag that mapstructure looks for is "mapstructure"
// but you can customize it using DecoderConfig.
//
// # Renaming Fields
//
// To rename the key that mapstructure looks for, use the "mapstructure"
// tag and set a value directly. For example, to change the "username" example
// above to "user":
//
// type User struct {
// Username string `mapstructure:"user"`
// }
//
// # Embedded Structs and Squashing
//
// Embedded structs are treated as if they're another field with that name.
// By default, the two structs below are equivalent when decoding with
// mapstructure:
//
// type Person struct {
// Name string
// }
//
// type Friend struct {
// Person
// }
//
// type Friend struct {
// Person Person
// }
//
// This would require an input that looks like below:
//
// map[string]interface{}{
// "person": map[string]interface{}{"name": "alice"},
// }
//
// If your "person" value is NOT nested, then you can append ",squash" to
// your tag value and mapstructure will treat it as if the embedded struct
// were part of the struct directly. Example:
//
// type Friend struct {
// Person `mapstructure:",squash"`
// }
//
// Now the following input would be accepted:
//
// map[string]interface{}{
// "name": "alice",
// }
//
// When decoding from a struct to a map, the squash tag squashes the struct
// fields into a single map. Using the example structs from above:
//
// Friend{Person: Person{Name: "alice"}}
//
// Will be decoded into a map:
//
// map[string]interface{}{
// "name": "alice",
// }
//
// DecoderConfig has a field that changes the behavior of mapstructure
// to always squash embedded structs.
//
// # Remainder Values
//
// If there are any unmapped keys in the source value, mapstructure by
// default will silently ignore them. You can error by setting ErrorUnused
// in DecoderConfig. If you're using Metadata you can also maintain a slice
// of the unused keys.
//
// You can also use the ",remain" suffix on your tag to collect all unused
// values in a map. The field with this tag MUST be a map type and should
// probably be a "map[string]interface{}" or "map[interface{}]interface{}".
// See example below:
//
// type Friend struct {
// Name string
// Other map[string]interface{} `mapstructure:",remain"`
// }
//
// Given the input below, Other would be populated with the other
// values that weren't used (everything but "name"):
//
// map[string]interface{}{
// "name": "bob",
// "address": "123 Maple St.",
// }
//
// # Omit Empty Values
//
// When decoding from a struct to any other value, you may use the
// ",omitempty" suffix on your tag to omit that value if it equates to
// the zero value. The zero value of all types is specified in the Go
// specification.
//
// For example, the zero type of a numeric type is zero ("0"). If the struct
// field value is zero and a numeric type, the field is empty, and it won't
// be encoded into the destination type.
//
// type Source struct {
// Age int `mapstructure:",omitempty"`
// }
//
// # Unexported fields
//
// Since unexported (private) struct fields cannot be set outside the package
// where they are defined, the decoder will simply skip them.
//
// For this output type definition:
//
// type Exported struct {
// private string // this unexported field will be skipped
// Public string
// }
//
// Using this map as input:
//
// map[string]interface{}{
// "private": "I will be ignored",
// "Public": "I made it through!",
// }
//
// The following struct will be decoded:
//
// type Exported struct {
// private: "" // field is left with an empty string (zero value)
// Public: "I made it through!"
// }
//
// # Other Configuration
//
// mapstructure is highly configurable. See the DecoderConfig struct
// for other features and options that are supported.
package mapstructure
import (
"encoding/json"
"errors"
"fmt"
"reflect"
"sort"
"strconv"
"strings"
)
// DecodeHookFunc is the callback function that can be used for
// data transformations. See "DecodeHook" in the DecoderConfig
// struct.
//
// The type must be one of DecodeHookFuncType, DecodeHookFuncKind, or
// DecodeHookFuncValue.
// Values are a superset of Types (Values can return types), and Types are a
// superset of Kinds (Types can return Kinds) and are generally a richer thing
// to use, but Kinds are simpler if you only need those.
//
// The reason DecodeHookFunc is multi-typed is for backwards compatibility:
// we started with Kinds and then realized Types were the better solution,
// but have a promise to not break backwards compat so we now support
// both.
type DecodeHookFunc interface{}
// DecodeHookFuncType is a DecodeHookFunc which has complete information about
// the source and target types.
type DecodeHookFuncType func(reflect.Type, reflect.Type, interface{}) (interface{}, error)
// DecodeHookFuncKind is a DecodeHookFunc which knows only the Kinds of the
// source and target types.
type DecodeHookFuncKind func(reflect.Kind, reflect.Kind, interface{}) (interface{}, error)
// DecodeHookFuncValue is a DecodeHookFunc which has complete access to both the source and target
// values.
type DecodeHookFuncValue func(from reflect.Value, to reflect.Value) (interface{}, error)
// DecoderConfig is the configuration that is used to create a new decoder
// and allows customization of various aspects of decoding.
type DecoderConfig struct {
// DecodeHook, if set, will be called before any decoding and any
// type conversion (if WeaklyTypedInput is on). This lets you modify
// the values before they're set down onto the resulting struct. The
// DecodeHook is called for every map and value in the input. This means
// that if a struct has embedded fields with squash tags the decode hook
// is called only once with all of the input data, not once for each
// embedded struct.
//
// If an error is returned, the entire decode will fail with that error.
DecodeHook DecodeHookFunc
// If ErrorUnused is true, then it is an error for there to exist
// keys in the original map that were unused in the decoding process
// (extra keys).
ErrorUnused bool
// If ErrorUnset is true, then it is an error for there to exist
// fields in the result that were not set in the decoding process
// (extra fields). This only applies to decoding to a struct. This
// will affect all nested structs as well.
ErrorUnset bool
// ZeroFields, if set to true, will zero fields before writing them.
// For example, a map will be emptied before decoded values are put in
// it. If this is false, a map will be merged.
ZeroFields bool
// If WeaklyTypedInput is true, the decoder will make the following
// "weak" conversions:
//
// - bools to string (true = "1", false = "0")
// - numbers to string (base 10)
// - bools to int/uint (true = 1, false = 0)
// - strings to int/uint (base implied by prefix)
// - int to bool (true if value != 0)
// - string to bool (accepts: 1, t, T, TRUE, true, True, 0, f, F,
// FALSE, false, False. Anything else is an error)
// - empty array = empty map and vice versa
// - negative numbers to overflowed uint values (base 10)
// - slice of maps to a merged map
// - single values are converted to slices if required. Each
// element is weakly decoded. For example: "4" can become []int{4}
// if the target type is an int slice.
//
WeaklyTypedInput bool
// Squash will squash embedded structs. A squash tag may also be
// added to an individual struct field using a tag. For example:
//
// type Parent struct {
// Child `mapstructure:",squash"`
// }
Squash bool
// Metadata is the struct that will contain extra metadata about
// the decoding. If this is nil, then no metadata will be tracked.
Metadata *Metadata
// Result is a pointer to the struct that will contain the decoded
// value.
Result interface{}
// The tag name that mapstructure reads for field names. This
// defaults to "mapstructure"
TagName string
// IgnoreUntaggedFields ignores all struct fields without explicit
// TagName, comparable to `mapstructure:"-"` as default behaviour.
IgnoreUntaggedFields bool
// MatchName is the function used to match the map key to the struct
// field name or tag. Defaults to `strings.EqualFold`. This can be used
// to implement case-sensitive tag values, support snake casing, etc.
MatchName func(mapKey, fieldName string) bool
}
// A Decoder takes a raw interface value and turns it into structured
// data, keeping track of rich error information along the way in case
// anything goes wrong. Unlike the basic top-level Decode method, you can
// more finely control how the Decoder behaves using the DecoderConfig
// structure. The top-level Decode method is just a convenience that sets
// up the most basic Decoder.
type Decoder struct {
config *DecoderConfig
}
// Metadata contains information about decoding a structure that
// is tedious or difficult to get otherwise.
type Metadata struct {
// Keys are the keys of the structure which were successfully decoded
Keys []string
// Unused is a slice of keys that were found in the raw value but
// weren't decoded since there was no matching field in the result interface
Unused []string
// Unset is a slice of field names that were found in the result interface
// but weren't set in the decoding process since there was no matching value
// in the input
Unset []string
}
// Decode takes an input structure and uses reflection to translate it to
// the output structure. output must be a pointer to a map or struct.
func Decode(input interface{}, output interface{}) error {
config := &DecoderConfig{
Metadata: nil,
Result: output,
}
decoder, err := NewDecoder(config)
if err != nil {
return err
}
return decoder.Decode(input)
}
// WeakDecode is the same as Decode but is shorthand to enable
// WeaklyTypedInput. See DecoderConfig for more info.
func WeakDecode(input, output interface{}) error {
config := &DecoderConfig{
Metadata: nil,
Result: output,
WeaklyTypedInput: true,
}
decoder, err := NewDecoder(config)
if err != nil {
return err
}
return decoder.Decode(input)
}
// DecodeMetadata is the same as Decode, but is shorthand to
// enable metadata collection. See DecoderConfig for more info.
func DecodeMetadata(input interface{}, output interface{}, metadata *Metadata) error {
config := &DecoderConfig{
Metadata: metadata,
Result: output,
}
decoder, err := NewDecoder(config)
if err != nil {
return err
}
return decoder.Decode(input)
}
// WeakDecodeMetadata is the same as Decode, but is shorthand to
// enable both WeaklyTypedInput and metadata collection. See
// DecoderConfig for more info.
func WeakDecodeMetadata(input interface{}, output interface{}, metadata *Metadata) error {
config := &DecoderConfig{
Metadata: metadata,
Result: output,
WeaklyTypedInput: true,
}
decoder, err := NewDecoder(config)
if err != nil {
return err
}
return decoder.Decode(input)
}
// NewDecoder returns a new decoder for the given configuration. Once
// a decoder has been returned, the same configuration must not be used
// again.
func NewDecoder(config *DecoderConfig) (*Decoder, error) {
val := reflect.ValueOf(config.Result)
if val.Kind() != reflect.Ptr {
return nil, errors.New("result must be a pointer")
}
val = val.Elem()
if !val.CanAddr() {
return nil, errors.New("result must be addressable (a pointer)")
}
if config.Metadata != nil {
if config.Metadata.Keys == nil {
config.Metadata.Keys = make([]string, 0)
}
if config.Metadata.Unused == nil {
config.Metadata.Unused = make([]string, 0)
}
if config.Metadata.Unset == nil {
config.Metadata.Unset = make([]string, 0)
}
}
if config.TagName == "" {
config.TagName = "mapstructure"
}
if config.MatchName == nil {
config.MatchName = strings.EqualFold
}
result := &Decoder{
config: config,
}
return result, nil
}
// Decode decodes the given raw interface to the target pointer specified
// by the configuration.
func (d *Decoder) Decode(input interface{}) error {
return d.decode("", input, reflect.ValueOf(d.config.Result).Elem())
}
// Decodes an unknown data type into a specific reflection value.
func (d *Decoder) decode(name string, input interface{}, outVal reflect.Value) error {
var inputVal reflect.Value
if input != nil {
inputVal = reflect.ValueOf(input)
// We need to check here if input is a typed nil. Typed nils won't
// match the "input == nil" below so we check that here.
if inputVal.Kind() == reflect.Ptr && inputVal.IsNil() {
input = nil
}
}
if input == nil {
// If the data is nil, then we don't set anything, unless ZeroFields is set
// to true.
if d.config.ZeroFields {
outVal.Set(reflect.Zero(outVal.Type()))
if d.config.Metadata != nil && name != "" {
d.config.Metadata.Keys = append(d.config.Metadata.Keys, name)
}
}
return nil
}
if !inputVal.IsValid() {
// If the input value is invalid, then we just set the value
// to be the zero value.
outVal.Set(reflect.Zero(outVal.Type()))
if d.config.Metadata != nil && name != "" {
d.config.Metadata.Keys = append(d.config.Metadata.Keys, name)
}
return nil
}
if d.config.DecodeHook != nil {
// We have a DecodeHook, so let's pre-process the input.
var err error
input, err = DecodeHookExec(d.config.DecodeHook, inputVal, outVal)
if err != nil {
return fmt.Errorf("error decoding '%s': %w", name, err)
}
}
var err error
outputKind := getKind(outVal)
addMetaKey := true
switch outputKind {
case reflect.Bool:
err = d.decodeBool(name, input, outVal)
case reflect.Interface:
err = d.decodeBasic(name, input, outVal)
case reflect.String:
err = d.decodeString(name, input, outVal)
case reflect.Int:
err = d.decodeInt(name, input, outVal)
case reflect.Uint:
err = d.decodeUint(name, input, outVal)
case reflect.Float32:
err = d.decodeFloat(name, input, outVal)
case reflect.Struct:
err = d.decodeStruct(name, input, outVal)
case reflect.Map:
err = d.decodeMap(name, input, outVal)
case reflect.Ptr:
addMetaKey, err = d.decodePtr(name, input, outVal)
case reflect.Slice:
err = d.decodeSlice(name, input, outVal)
case reflect.Array:
err = d.decodeArray(name, input, outVal)
case reflect.Func:
err = d.decodeFunc(name, input, outVal)
default:
// If we reached this point then we weren't able to decode it
return fmt.Errorf("%s: unsupported type: %s", name, outputKind)
}
// If we reached here, then we successfully decoded SOMETHING, so
// mark the key as used if we're tracking metainput.
if addMetaKey && d.config.Metadata != nil && name != "" {
d.config.Metadata.Keys = append(d.config.Metadata.Keys, name)
}
return err
}
// This decodes a basic type (bool, int, string, etc.) and sets the
// value to "data" of that type.
func (d *Decoder) decodeBasic(name string, data interface{}, val reflect.Value) error {
if val.IsValid() && val.Elem().IsValid() {
elem := val.Elem()
// If we can't address this element, then its not writable. Instead,
// we make a copy of the value (which is a pointer and therefore
// writable), decode into that, and replace the whole value.
copied := false
if !elem.CanAddr() {
copied = true
// Make *T
copy := reflect.New(elem.Type())
// *T = elem
copy.Elem().Set(elem)
// Set elem so we decode into it
elem = copy
}
// Decode. If we have an error then return. We also return right
// away if we're not a copy because that means we decoded directly.
if err := d.decode(name, data, elem); err != nil || !copied {
return err
}
// If we're a copy, we need to set te final result
val.Set(elem.Elem())
return nil
}
dataVal := reflect.ValueOf(data)
// If the input data is a pointer, and the assigned type is the dereference
// of that exact pointer, then indirect it so that we can assign it.
// Example: *string to string
if dataVal.Kind() == reflect.Ptr && dataVal.Type().Elem() == val.Type() {
dataVal = reflect.Indirect(dataVal)
}
if !dataVal.IsValid() {
dataVal = reflect.Zero(val.Type())
}
dataValType := dataVal.Type()
if !dataValType.AssignableTo(val.Type()) {
return fmt.Errorf(
"'%s' expected type '%s', got '%s'",
name, val.Type(), dataValType)
}
val.Set(dataVal)
return nil
}
func (d *Decoder) decodeString(name string, data interface{}, val reflect.Value) error {
dataVal := reflect.Indirect(reflect.ValueOf(data))
dataKind := getKind(dataVal)
converted := true
switch {
case dataKind == reflect.String:
val.SetString(dataVal.String())
case dataKind == reflect.Bool && d.config.WeaklyTypedInput:
if dataVal.Bool() {
val.SetString("1")
} else {
val.SetString("0")
}
case dataKind == reflect.Int && d.config.WeaklyTypedInput:
val.SetString(strconv.FormatInt(dataVal.Int(), 10))
case dataKind == reflect.Uint && d.config.WeaklyTypedInput:
val.SetString(strconv.FormatUint(dataVal.Uint(), 10))
case dataKind == reflect.Float32 && d.config.WeaklyTypedInput:
val.SetString(strconv.FormatFloat(dataVal.Float(), 'f', -1, 64))
case dataKind == reflect.Slice && d.config.WeaklyTypedInput,
dataKind == reflect.Array && d.config.WeaklyTypedInput:
dataType := dataVal.Type()
elemKind := dataType.Elem().Kind()
switch elemKind {
case reflect.Uint8:
var uints []uint8
if dataKind == reflect.Array {
uints = make([]uint8, dataVal.Len())
for i := range uints {
uints[i] = dataVal.Index(i).Interface().(uint8)
}
} else {
uints = dataVal.Interface().([]uint8)
}
val.SetString(string(uints))
default:
converted = false
}
default:
converted = false
}
if !converted {
return fmt.Errorf(
"'%s' expected type '%s', got unconvertible type '%s', value: '%v'",
name, val.Type(), dataVal.Type(), data)
}
return nil
}
func (d *Decoder) decodeInt(name string, data interface{}, val reflect.Value) error {
dataVal := reflect.Indirect(reflect.ValueOf(data))
dataKind := getKind(dataVal)
dataType := dataVal.Type()
switch {
case dataKind == reflect.Int:
val.SetInt(dataVal.Int())
case dataKind == reflect.Uint:
val.SetInt(int64(dataVal.Uint()))
case dataKind == reflect.Float32:
val.SetInt(int64(dataVal.Float()))
case dataKind == reflect.Bool && d.config.WeaklyTypedInput:
if dataVal.Bool() {
val.SetInt(1)
} else {
val.SetInt(0)
}
case dataKind == reflect.String && d.config.WeaklyTypedInput:
str := dataVal.String()
if str == "" {
str = "0"
}
i, err := strconv.ParseInt(str, 0, val.Type().Bits())
if err == nil {
val.SetInt(i)
} else {
return fmt.Errorf("cannot parse '%s' as int: %s", name, err)
}
case dataType.PkgPath() == "encoding/json" && dataType.Name() == "Number":
jn := data.(json.Number)
i, err := jn.Int64()
if err != nil {
return fmt.Errorf(
"error decoding json.Number into %s: %s", name, err)
}
val.SetInt(i)
default:
return fmt.Errorf(
"'%s' expected type '%s', got unconvertible type '%s', value: '%v'",
name, val.Type(), dataVal.Type(), data)
}
return nil
}
func (d *Decoder) decodeUint(name string, data interface{}, val reflect.Value) error {
dataVal := reflect.Indirect(reflect.ValueOf(data))
dataKind := getKind(dataVal)
dataType := dataVal.Type()
switch {
case dataKind == reflect.Int:
i := dataVal.Int()
if i < 0 && !d.config.WeaklyTypedInput {
return fmt.Errorf("cannot parse '%s', %d overflows uint",
name, i)
}
val.SetUint(uint64(i))
case dataKind == reflect.Uint:
val.SetUint(dataVal.Uint())
case dataKind == reflect.Float32:
f := dataVal.Float()
if f < 0 && !d.config.WeaklyTypedInput {
return fmt.Errorf("cannot parse '%s', %f overflows uint",
name, f)
}
val.SetUint(uint64(f))
case dataKind == reflect.Bool && d.config.WeaklyTypedInput:
if dataVal.Bool() {
val.SetUint(1)
} else {
val.SetUint(0)
}
case dataKind == reflect.String && d.config.WeaklyTypedInput:
str := dataVal.String()
if str == "" {
str = "0"
}
i, err := strconv.ParseUint(str, 0, val.Type().Bits())
if err == nil {
val.SetUint(i)
} else {
return fmt.Errorf("cannot parse '%s' as uint: %s", name, err)
}
case dataType.PkgPath() == "encoding/json" && dataType.Name() == "Number":
jn := data.(json.Number)
i, err := strconv.ParseUint(string(jn), 0, 64)
if err != nil {
return fmt.Errorf(
"error decoding json.Number into %s: %s", name, err)
}
val.SetUint(i)
default:
return fmt.Errorf(
"'%s' expected type '%s', got unconvertible type '%s', value: '%v'",
name, val.Type(), dataVal.Type(), data)
}
return nil
}
func (d *Decoder) decodeBool(name string, data interface{}, val reflect.Value) error {
dataVal := reflect.Indirect(reflect.ValueOf(data))
dataKind := getKind(dataVal)
switch {
case dataKind == reflect.Bool:
val.SetBool(dataVal.Bool())
case dataKind == reflect.Int && d.config.WeaklyTypedInput:
val.SetBool(dataVal.Int() != 0)
case dataKind == reflect.Uint && d.config.WeaklyTypedInput:
val.SetBool(dataVal.Uint() != 0)
case dataKind == reflect.Float32 && d.config.WeaklyTypedInput:
val.SetBool(dataVal.Float() != 0)
case dataKind == reflect.String && d.config.WeaklyTypedInput:
b, err := strconv.ParseBool(dataVal.String())
if err == nil {
val.SetBool(b)
} else if dataVal.String() == "" {
val.SetBool(false)
} else {
return fmt.Errorf("cannot parse '%s' as bool: %s", name, err)
}
default:
return fmt.Errorf(
"'%s' expected type '%s', got unconvertible type '%s', value: '%v'",
name, val.Type(), dataVal.Type(), data)
}
return nil
}
func (d *Decoder) decodeFloat(name string, data interface{}, val reflect.Value) error {
dataVal := reflect.Indirect(reflect.ValueOf(data))
dataKind := getKind(dataVal)
dataType := dataVal.Type()
switch {
case dataKind == reflect.Int:
val.SetFloat(float64(dataVal.Int()))
case dataKind == reflect.Uint:
val.SetFloat(float64(dataVal.Uint()))
case dataKind == reflect.Float32:
val.SetFloat(dataVal.Float())
case dataKind == reflect.Bool && d.config.WeaklyTypedInput:
if dataVal.Bool() {
val.SetFloat(1)
} else {
val.SetFloat(0)
}
case dataKind == reflect.String && d.config.WeaklyTypedInput:
str := dataVal.String()
if str == "" {
str = "0"
}
f, err := strconv.ParseFloat(str, val.Type().Bits())
if err == nil {
val.SetFloat(f)
} else {
return fmt.Errorf("cannot parse '%s' as float: %s", name, err)
}
case dataType.PkgPath() == "encoding/json" && dataType.Name() == "Number":
jn := data.(json.Number)
i, err := jn.Float64()
if err != nil {
return fmt.Errorf(
"error decoding json.Number into %s: %s", name, err)
}
val.SetFloat(i)
default:
return fmt.Errorf(
"'%s' expected type '%s', got unconvertible type '%s', value: '%v'",
name, val.Type(), dataVal.Type(), data)
}
return nil
}
func (d *Decoder) decodeMap(name string, data interface{}, val reflect.Value) error {
valType := val.Type()
valKeyType := valType.Key()
valElemType := valType.Elem()
// By default we overwrite keys in the current map
valMap := val
// If the map is nil or we're purposely zeroing fields, make a new map
if valMap.IsNil() || d.config.ZeroFields {
// Make a new map to hold our result
mapType := reflect.MapOf(valKeyType, valElemType)
valMap = reflect.MakeMap(mapType)
}
// Check input type and based on the input type jump to the proper func
dataVal := reflect.Indirect(reflect.ValueOf(data))
switch dataVal.Kind() {
case reflect.Map:
return d.decodeMapFromMap(name, dataVal, val, valMap)
case reflect.Struct:
return d.decodeMapFromStruct(name, dataVal, val, valMap)
case reflect.Array, reflect.Slice:
if d.config.WeaklyTypedInput {
return d.decodeMapFromSlice(name, dataVal, val, valMap)
}
fallthrough
default:
return fmt.Errorf("'%s' expected a map, got '%s'", name, dataVal.Kind())
}
}
func (d *Decoder) decodeMapFromSlice(name string, dataVal reflect.Value, val reflect.Value, valMap reflect.Value) error {
// Special case for BC reasons (covered by tests)
if dataVal.Len() == 0 {
val.Set(valMap)
return nil
}
for i := 0; i < dataVal.Len(); i++ {
err := d.decode(
name+"["+strconv.Itoa(i)+"]",
dataVal.Index(i).Interface(), val)
if err != nil {
return err
}
}
return nil
}
func (d *Decoder) decodeMapFromMap(name string, dataVal reflect.Value, val reflect.Value, valMap reflect.Value) error {
valType := val.Type()
valKeyType := valType.Key()
valElemType := valType.Elem()
// Accumulate errors
errors := make([]string, 0)
// If the input data is empty, then we just match what the input data is.
if dataVal.Len() == 0 {
if dataVal.IsNil() {
if !val.IsNil() {
val.Set(dataVal)
}
} else {
// Set to empty allocated value
val.Set(valMap)
}
return nil
}
for _, k := range dataVal.MapKeys() {
fieldName := name + "[" + k.String() + "]"
// First decode the key into the proper type
currentKey := reflect.Indirect(reflect.New(valKeyType))
if err := d.decode(fieldName, k.Interface(), currentKey); err != nil {
errors = appendErrors(errors, err)
continue
}
// Next decode the data into the proper type
v := dataVal.MapIndex(k).Interface()
currentVal := reflect.Indirect(reflect.New(valElemType))
if err := d.decode(fieldName, v, currentVal); err != nil {
errors = appendErrors(errors, err)
continue
}
valMap.SetMapIndex(currentKey, currentVal)
}
// Set the built up map to the value
val.Set(valMap)
// If we had errors, return those
if len(errors) > 0 {
return &Error{errors}
}
return nil
}
func (d *Decoder) decodeMapFromStruct(name string, dataVal reflect.Value, val reflect.Value, valMap reflect.Value) error {
typ := dataVal.Type()
for i := 0; i < typ.NumField(); i++ {
// Get the StructField first since this is a cheap operation. If the
// field is unexported, then ignore it.
f := typ.Field(i)
if f.PkgPath != "" {
continue
}
// Next get the actual value of this field and verify it is assignable
// to the map value.
v := dataVal.Field(i)
if !v.Type().AssignableTo(valMap.Type().Elem()) {
return fmt.Errorf("cannot assign type '%s' to map value field of type '%s'", v.Type(), valMap.Type().Elem())
}
tagValue := f.Tag.Get(d.config.TagName)
keyName := f.Name
if tagValue == "" && d.config.IgnoreUntaggedFields {
continue
}
// If Squash is set in the config, we squash the field down.
squash := d.config.Squash && v.Kind() == reflect.Struct && f.Anonymous
v = dereferencePtrToStructIfNeeded(v, d.config.TagName)
// Determine the name of the key in the map
if index := strings.Index(tagValue, ","); index != -1 {
if tagValue[:index] == "-" {
continue
}
// If "omitempty" is specified in the tag, it ignores empty values.
if strings.Contains(tagValue[index+1:], "omitempty") && isEmptyValue(v) {
continue
}
// If "squash" is specified in the tag, we squash the field down.
squash = squash || strings.Contains(tagValue[index+1:], "squash")
if squash {
// When squashing, the embedded type can be a pointer to a struct.
if v.Kind() == reflect.Ptr && v.Elem().Kind() == reflect.Struct {
v = v.Elem()
}
// The final type must be a struct
if v.Kind() != reflect.Struct {
return fmt.Errorf("cannot squash non-struct type '%s'", v.Type())
}
}
if keyNameTagValue := tagValue[:index]; keyNameTagValue != "" {
keyName = keyNameTagValue
}
} else if len(tagValue) > 0 {
if tagValue == "-" {
continue
}
keyName = tagValue
}
switch v.Kind() {
// this is an embedded struct, so handle it differently
case reflect.Struct:
x := reflect.New(v.Type())
x.Elem().Set(v)
vType := valMap.Type()
vKeyType := vType.Key()
vElemType := vType.Elem()
mType := reflect.MapOf(vKeyType, vElemType)
vMap := reflect.MakeMap(mType)
// Creating a pointer to a map so that other methods can completely
// overwrite the map if need be (looking at you decodeMapFromMap). The
// indirection allows the underlying map to be settable (CanSet() == true)
// where as reflect.MakeMap returns an unsettable map.
addrVal := reflect.New(vMap.Type())
reflect.Indirect(addrVal).Set(vMap)
err := d.decode(keyName, x.Interface(), reflect.Indirect(addrVal))
if err != nil {
return err
}
// the underlying map may have been completely overwritten so pull
// it indirectly out of the enclosing value.
vMap = reflect.Indirect(addrVal)
if squash {
for _, k := range vMap.MapKeys() {
valMap.SetMapIndex(k, vMap.MapIndex(k))
You can’t perform that action at this time.