blob: 05e8fbf1fedd4834e4513f46b9df07a0d5c25840 [file] [log] [blame]
khenaidooab1f7bd2019-11-14 14:00:27 -05001package jsoniter
2
3import (
4 "fmt"
5 "github.com/modern-go/reflect2"
6 "reflect"
7 "sort"
8 "strings"
9 "unicode"
10 "unsafe"
11)
12
13var typeDecoders = map[string]ValDecoder{}
14var fieldDecoders = map[string]ValDecoder{}
15var typeEncoders = map[string]ValEncoder{}
16var fieldEncoders = map[string]ValEncoder{}
17var extensions = []Extension{}
18
19// StructDescriptor describe how should we encode/decode the struct
20type StructDescriptor struct {
21 Type reflect2.Type
22 Fields []*Binding
23}
24
25// GetField get one field from the descriptor by its name.
26// Can not use map here to keep field orders.
27func (structDescriptor *StructDescriptor) GetField(fieldName string) *Binding {
28 for _, binding := range structDescriptor.Fields {
29 if binding.Field.Name() == fieldName {
30 return binding
31 }
32 }
33 return nil
34}
35
36// Binding describe how should we encode/decode the struct field
37type Binding struct {
38 levels []int
39 Field reflect2.StructField
40 FromNames []string
41 ToNames []string
42 Encoder ValEncoder
43 Decoder ValDecoder
44}
45
46// Extension the one for all SPI. Customize encoding/decoding by specifying alternate encoder/decoder.
47// Can also rename fields by UpdateStructDescriptor.
48type Extension interface {
49 UpdateStructDescriptor(structDescriptor *StructDescriptor)
50 CreateMapKeyDecoder(typ reflect2.Type) ValDecoder
51 CreateMapKeyEncoder(typ reflect2.Type) ValEncoder
52 CreateDecoder(typ reflect2.Type) ValDecoder
53 CreateEncoder(typ reflect2.Type) ValEncoder
54 DecorateDecoder(typ reflect2.Type, decoder ValDecoder) ValDecoder
55 DecorateEncoder(typ reflect2.Type, encoder ValEncoder) ValEncoder
56}
57
58// DummyExtension embed this type get dummy implementation for all methods of Extension
59type DummyExtension struct {
60}
61
62// UpdateStructDescriptor No-op
63func (extension *DummyExtension) UpdateStructDescriptor(structDescriptor *StructDescriptor) {
64}
65
66// CreateMapKeyDecoder No-op
67func (extension *DummyExtension) CreateMapKeyDecoder(typ reflect2.Type) ValDecoder {
68 return nil
69}
70
71// CreateMapKeyEncoder No-op
72func (extension *DummyExtension) CreateMapKeyEncoder(typ reflect2.Type) ValEncoder {
73 return nil
74}
75
76// CreateDecoder No-op
77func (extension *DummyExtension) CreateDecoder(typ reflect2.Type) ValDecoder {
78 return nil
79}
80
81// CreateEncoder No-op
82func (extension *DummyExtension) CreateEncoder(typ reflect2.Type) ValEncoder {
83 return nil
84}
85
86// DecorateDecoder No-op
87func (extension *DummyExtension) DecorateDecoder(typ reflect2.Type, decoder ValDecoder) ValDecoder {
88 return decoder
89}
90
91// DecorateEncoder No-op
92func (extension *DummyExtension) DecorateEncoder(typ reflect2.Type, encoder ValEncoder) ValEncoder {
93 return encoder
94}
95
96type EncoderExtension map[reflect2.Type]ValEncoder
97
98// UpdateStructDescriptor No-op
99func (extension EncoderExtension) UpdateStructDescriptor(structDescriptor *StructDescriptor) {
100}
101
102// CreateDecoder No-op
103func (extension EncoderExtension) CreateDecoder(typ reflect2.Type) ValDecoder {
104 return nil
105}
106
107// CreateEncoder get encoder from map
108func (extension EncoderExtension) CreateEncoder(typ reflect2.Type) ValEncoder {
109 return extension[typ]
110}
111
112// CreateMapKeyDecoder No-op
113func (extension EncoderExtension) CreateMapKeyDecoder(typ reflect2.Type) ValDecoder {
114 return nil
115}
116
117// CreateMapKeyEncoder No-op
118func (extension EncoderExtension) CreateMapKeyEncoder(typ reflect2.Type) ValEncoder {
119 return nil
120}
121
122// DecorateDecoder No-op
123func (extension EncoderExtension) DecorateDecoder(typ reflect2.Type, decoder ValDecoder) ValDecoder {
124 return decoder
125}
126
127// DecorateEncoder No-op
128func (extension EncoderExtension) DecorateEncoder(typ reflect2.Type, encoder ValEncoder) ValEncoder {
129 return encoder
130}
131
132type DecoderExtension map[reflect2.Type]ValDecoder
133
134// UpdateStructDescriptor No-op
135func (extension DecoderExtension) UpdateStructDescriptor(structDescriptor *StructDescriptor) {
136}
137
138// CreateMapKeyDecoder No-op
139func (extension DecoderExtension) CreateMapKeyDecoder(typ reflect2.Type) ValDecoder {
140 return nil
141}
142
143// CreateMapKeyEncoder No-op
144func (extension DecoderExtension) CreateMapKeyEncoder(typ reflect2.Type) ValEncoder {
145 return nil
146}
147
148// CreateDecoder get decoder from map
149func (extension DecoderExtension) CreateDecoder(typ reflect2.Type) ValDecoder {
150 return extension[typ]
151}
152
153// CreateEncoder No-op
154func (extension DecoderExtension) CreateEncoder(typ reflect2.Type) ValEncoder {
155 return nil
156}
157
158// DecorateDecoder No-op
159func (extension DecoderExtension) DecorateDecoder(typ reflect2.Type, decoder ValDecoder) ValDecoder {
160 return decoder
161}
162
163// DecorateEncoder No-op
164func (extension DecoderExtension) DecorateEncoder(typ reflect2.Type, encoder ValEncoder) ValEncoder {
165 return encoder
166}
167
168type funcDecoder struct {
169 fun DecoderFunc
170}
171
172func (decoder *funcDecoder) Decode(ptr unsafe.Pointer, iter *Iterator) {
173 decoder.fun(ptr, iter)
174}
175
176type funcEncoder struct {
177 fun EncoderFunc
178 isEmptyFunc func(ptr unsafe.Pointer) bool
179}
180
181func (encoder *funcEncoder) Encode(ptr unsafe.Pointer, stream *Stream) {
182 encoder.fun(ptr, stream)
183}
184
185func (encoder *funcEncoder) IsEmpty(ptr unsafe.Pointer) bool {
186 if encoder.isEmptyFunc == nil {
187 return false
188 }
189 return encoder.isEmptyFunc(ptr)
190}
191
192// DecoderFunc the function form of TypeDecoder
193type DecoderFunc func(ptr unsafe.Pointer, iter *Iterator)
194
195// EncoderFunc the function form of TypeEncoder
196type EncoderFunc func(ptr unsafe.Pointer, stream *Stream)
197
198// RegisterTypeDecoderFunc register TypeDecoder for a type with function
199func RegisterTypeDecoderFunc(typ string, fun DecoderFunc) {
200 typeDecoders[typ] = &funcDecoder{fun}
201}
202
203// RegisterTypeDecoder register TypeDecoder for a typ
204func RegisterTypeDecoder(typ string, decoder ValDecoder) {
205 typeDecoders[typ] = decoder
206}
207
208// RegisterFieldDecoderFunc register TypeDecoder for a struct field with function
209func RegisterFieldDecoderFunc(typ string, field string, fun DecoderFunc) {
210 RegisterFieldDecoder(typ, field, &funcDecoder{fun})
211}
212
213// RegisterFieldDecoder register TypeDecoder for a struct field
214func RegisterFieldDecoder(typ string, field string, decoder ValDecoder) {
215 fieldDecoders[fmt.Sprintf("%s/%s", typ, field)] = decoder
216}
217
218// RegisterTypeEncoderFunc register TypeEncoder for a type with encode/isEmpty function
219func RegisterTypeEncoderFunc(typ string, fun EncoderFunc, isEmptyFunc func(unsafe.Pointer) bool) {
220 typeEncoders[typ] = &funcEncoder{fun, isEmptyFunc}
221}
222
223// RegisterTypeEncoder register TypeEncoder for a type
224func RegisterTypeEncoder(typ string, encoder ValEncoder) {
225 typeEncoders[typ] = encoder
226}
227
228// RegisterFieldEncoderFunc register TypeEncoder for a struct field with encode/isEmpty function
229func RegisterFieldEncoderFunc(typ string, field string, fun EncoderFunc, isEmptyFunc func(unsafe.Pointer) bool) {
230 RegisterFieldEncoder(typ, field, &funcEncoder{fun, isEmptyFunc})
231}
232
233// RegisterFieldEncoder register TypeEncoder for a struct field
234func RegisterFieldEncoder(typ string, field string, encoder ValEncoder) {
235 fieldEncoders[fmt.Sprintf("%s/%s", typ, field)] = encoder
236}
237
238// RegisterExtension register extension
239func RegisterExtension(extension Extension) {
240 extensions = append(extensions, extension)
241}
242
243func getTypeDecoderFromExtension(ctx *ctx, typ reflect2.Type) ValDecoder {
244 decoder := _getTypeDecoderFromExtension(ctx, typ)
245 if decoder != nil {
246 for _, extension := range extensions {
247 decoder = extension.DecorateDecoder(typ, decoder)
248 }
249 decoder = ctx.decoderExtension.DecorateDecoder(typ, decoder)
250 for _, extension := range ctx.extraExtensions {
251 decoder = extension.DecorateDecoder(typ, decoder)
252 }
253 }
254 return decoder
255}
256func _getTypeDecoderFromExtension(ctx *ctx, typ reflect2.Type) ValDecoder {
257 for _, extension := range extensions {
258 decoder := extension.CreateDecoder(typ)
259 if decoder != nil {
260 return decoder
261 }
262 }
263 decoder := ctx.decoderExtension.CreateDecoder(typ)
264 if decoder != nil {
265 return decoder
266 }
267 for _, extension := range ctx.extraExtensions {
268 decoder := extension.CreateDecoder(typ)
269 if decoder != nil {
270 return decoder
271 }
272 }
273 typeName := typ.String()
274 decoder = typeDecoders[typeName]
275 if decoder != nil {
276 return decoder
277 }
278 if typ.Kind() == reflect.Ptr {
279 ptrType := typ.(*reflect2.UnsafePtrType)
280 decoder := typeDecoders[ptrType.Elem().String()]
281 if decoder != nil {
282 return &OptionalDecoder{ptrType.Elem(), decoder}
283 }
284 }
285 return nil
286}
287
288func getTypeEncoderFromExtension(ctx *ctx, typ reflect2.Type) ValEncoder {
289 encoder := _getTypeEncoderFromExtension(ctx, typ)
290 if encoder != nil {
291 for _, extension := range extensions {
292 encoder = extension.DecorateEncoder(typ, encoder)
293 }
294 encoder = ctx.encoderExtension.DecorateEncoder(typ, encoder)
295 for _, extension := range ctx.extraExtensions {
296 encoder = extension.DecorateEncoder(typ, encoder)
297 }
298 }
299 return encoder
300}
301
302func _getTypeEncoderFromExtension(ctx *ctx, typ reflect2.Type) ValEncoder {
303 for _, extension := range extensions {
304 encoder := extension.CreateEncoder(typ)
305 if encoder != nil {
306 return encoder
307 }
308 }
309 encoder := ctx.encoderExtension.CreateEncoder(typ)
310 if encoder != nil {
311 return encoder
312 }
313 for _, extension := range ctx.extraExtensions {
314 encoder := extension.CreateEncoder(typ)
315 if encoder != nil {
316 return encoder
317 }
318 }
319 typeName := typ.String()
320 encoder = typeEncoders[typeName]
321 if encoder != nil {
322 return encoder
323 }
324 if typ.Kind() == reflect.Ptr {
325 typePtr := typ.(*reflect2.UnsafePtrType)
326 encoder := typeEncoders[typePtr.Elem().String()]
327 if encoder != nil {
328 return &OptionalEncoder{encoder}
329 }
330 }
331 return nil
332}
333
334func describeStruct(ctx *ctx, typ reflect2.Type) *StructDescriptor {
335 structType := typ.(*reflect2.UnsafeStructType)
336 embeddedBindings := []*Binding{}
337 bindings := []*Binding{}
338 for i := 0; i < structType.NumField(); i++ {
339 field := structType.Field(i)
340 tag, hastag := field.Tag().Lookup(ctx.getTagKey())
341 if ctx.onlyTaggedField && !hastag && !field.Anonymous() {
342 continue
343 }
344 tagParts := strings.Split(tag, ",")
345 if tag == "-" {
346 continue
347 }
348 if field.Anonymous() && (tag == "" || tagParts[0] == "") {
349 if field.Type().Kind() == reflect.Struct {
350 structDescriptor := describeStruct(ctx, field.Type())
351 for _, binding := range structDescriptor.Fields {
352 binding.levels = append([]int{i}, binding.levels...)
353 omitempty := binding.Encoder.(*structFieldEncoder).omitempty
354 binding.Encoder = &structFieldEncoder{field, binding.Encoder, omitempty}
355 binding.Decoder = &structFieldDecoder{field, binding.Decoder}
356 embeddedBindings = append(embeddedBindings, binding)
357 }
358 continue
359 } else if field.Type().Kind() == reflect.Ptr {
360 ptrType := field.Type().(*reflect2.UnsafePtrType)
361 if ptrType.Elem().Kind() == reflect.Struct {
362 structDescriptor := describeStruct(ctx, ptrType.Elem())
363 for _, binding := range structDescriptor.Fields {
364 binding.levels = append([]int{i}, binding.levels...)
365 omitempty := binding.Encoder.(*structFieldEncoder).omitempty
366 binding.Encoder = &dereferenceEncoder{binding.Encoder}
367 binding.Encoder = &structFieldEncoder{field, binding.Encoder, omitempty}
368 binding.Decoder = &dereferenceDecoder{ptrType.Elem(), binding.Decoder}
369 binding.Decoder = &structFieldDecoder{field, binding.Decoder}
370 embeddedBindings = append(embeddedBindings, binding)
371 }
372 continue
373 }
374 }
375 }
376 fieldNames := calcFieldNames(field.Name(), tagParts[0], tag)
377 fieldCacheKey := fmt.Sprintf("%s/%s", typ.String(), field.Name())
378 decoder := fieldDecoders[fieldCacheKey]
379 if decoder == nil {
380 decoder = decoderOfType(ctx.append(field.Name()), field.Type())
381 }
382 encoder := fieldEncoders[fieldCacheKey]
383 if encoder == nil {
384 encoder = encoderOfType(ctx.append(field.Name()), field.Type())
385 }
386 binding := &Binding{
387 Field: field,
388 FromNames: fieldNames,
389 ToNames: fieldNames,
390 Decoder: decoder,
391 Encoder: encoder,
392 }
393 binding.levels = []int{i}
394 bindings = append(bindings, binding)
395 }
396 return createStructDescriptor(ctx, typ, bindings, embeddedBindings)
397}
398func createStructDescriptor(ctx *ctx, typ reflect2.Type, bindings []*Binding, embeddedBindings []*Binding) *StructDescriptor {
399 structDescriptor := &StructDescriptor{
400 Type: typ,
401 Fields: bindings,
402 }
403 for _, extension := range extensions {
404 extension.UpdateStructDescriptor(structDescriptor)
405 }
406 ctx.encoderExtension.UpdateStructDescriptor(structDescriptor)
407 ctx.decoderExtension.UpdateStructDescriptor(structDescriptor)
408 for _, extension := range ctx.extraExtensions {
409 extension.UpdateStructDescriptor(structDescriptor)
410 }
411 processTags(structDescriptor, ctx.frozenConfig)
412 // merge normal & embedded bindings & sort with original order
413 allBindings := sortableBindings(append(embeddedBindings, structDescriptor.Fields...))
414 sort.Sort(allBindings)
415 structDescriptor.Fields = allBindings
416 return structDescriptor
417}
418
419type sortableBindings []*Binding
420
421func (bindings sortableBindings) Len() int {
422 return len(bindings)
423}
424
425func (bindings sortableBindings) Less(i, j int) bool {
426 left := bindings[i].levels
427 right := bindings[j].levels
428 k := 0
429 for {
430 if left[k] < right[k] {
431 return true
432 } else if left[k] > right[k] {
433 return false
434 }
435 k++
436 }
437}
438
439func (bindings sortableBindings) Swap(i, j int) {
440 bindings[i], bindings[j] = bindings[j], bindings[i]
441}
442
443func processTags(structDescriptor *StructDescriptor, cfg *frozenConfig) {
444 for _, binding := range structDescriptor.Fields {
445 shouldOmitEmpty := false
446 tagParts := strings.Split(binding.Field.Tag().Get(cfg.getTagKey()), ",")
447 for _, tagPart := range tagParts[1:] {
448 if tagPart == "omitempty" {
449 shouldOmitEmpty = true
450 } else if tagPart == "string" {
451 if binding.Field.Type().Kind() == reflect.String {
452 binding.Decoder = &stringModeStringDecoder{binding.Decoder, cfg}
453 binding.Encoder = &stringModeStringEncoder{binding.Encoder, cfg}
454 } else {
455 binding.Decoder = &stringModeNumberDecoder{binding.Decoder}
456 binding.Encoder = &stringModeNumberEncoder{binding.Encoder}
457 }
458 }
459 }
460 binding.Decoder = &structFieldDecoder{binding.Field, binding.Decoder}
461 binding.Encoder = &structFieldEncoder{binding.Field, binding.Encoder, shouldOmitEmpty}
462 }
463}
464
465func calcFieldNames(originalFieldName string, tagProvidedFieldName string, wholeTag string) []string {
466 // ignore?
467 if wholeTag == "-" {
468 return []string{}
469 }
470 // rename?
471 var fieldNames []string
472 if tagProvidedFieldName == "" {
473 fieldNames = []string{originalFieldName}
474 } else {
475 fieldNames = []string{tagProvidedFieldName}
476 }
477 // private?
478 isNotExported := unicode.IsLower(rune(originalFieldName[0]))
479 if isNotExported {
480 fieldNames = []string{}
481 }
482 return fieldNames
483}