-
Notifications
You must be signed in to change notification settings - Fork 0
/
encoder.go
399 lines (341 loc) · 8.61 KB
/
encoder.go
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
package gql_auto
import (
"fmt"
"reflect"
"strings"
"unicode"
"github.com/graphql-go/graphql"
)
type Encoder struct {
types map[string]graphql.Type
}
func NewEncoder() *Encoder {
return &Encoder{
types: make(map[string]graphql.Type),
}
}
var DefaultEncoder = NewEncoder()
func (enc *Encoder) Struct(obj interface{}, options ...Option) (*graphql.Object, error) {
t := reflect.TypeOf(obj)
return enc.StructOf(t, options...)
}
func (enc *Encoder) Args(obj interface{}) (graphql.FieldConfigArgument, error) {
t := reflect.TypeOf(obj)
return enc.ArgsOf(t)
}
func toLowerCamelCase(input string) string {
fieldName := []rune(input)
lastUppercase := false
for i := 0; i < len(fieldName); i++ {
lowerCase := true
hasAnotherLetter := len(fieldName) > i+1
// The first letter will always be lower case
if i > 0 {
if hasAnotherLetter {
// Keep only the final capital letter of the start of word
// i.e. ACTTest -> actTest
// If the next character is upper
lowerCase = unicode.IsUpper(fieldName[i+1])
}
if (len(fieldName) == (i + 2)) && lastUppercase {
lowerCase = true
}
}
lastUppercase = unicode.IsUpper(fieldName[i])
if lowerCase {
fieldName[i] = unicode.ToLower(fieldName[i])
}
}
return string(fieldName)
}
// StructOf returns a `*graphql.Object` with the description extracted from the
// obj passed.
//
// This method extracts the information needed from the fields of the obj
// informed. All fields tagged with "graphql" are added.
//
// The "graphql" tag can be defined as:
//
// ```
//
// type T struct {
// field string `graphql:"fieldname"`
// }
//
// ```
//
// * fieldname: The name of the field.
func (enc *Encoder) StructOf(t reflect.Type, options ...Option) (*graphql.Object, error) {
if r, ok := enc.getType(t); ok {
if d, ok := r.(*graphql.Object); ok {
return d, nil
}
return nil, fmt.Errorf("%s is not an graphql.Object", r)
}
name := t.Name()
if t.Kind() == reflect.Ptr {
name = t.Elem().Name()
}
objCfg := graphql.ObjectConfig{
Name: name,
Fields: graphql.Fields{},
}
// Apply options
for _, opt := range options {
err := opt.Apply(&objCfg)
if err != nil {
return nil, err
}
}
r := graphql.NewObject(objCfg)
enc.registerType(t, r)
if t.Kind() == reflect.Ptr {
t = t.Elem()
}
// Goes field by field of the object.
for i := 0; i < t.NumField(); i++ {
field := t.Field(i)
// if the field is not exported, ignore it
if field.PkgPath != "" {
continue
}
tag, ok := field.Tag.Lookup("graphql")
// if there is no graphql tag look for a json tag
if !ok {
tag, ok = field.Tag.Lookup("json")
if ok {
tag = strings.Replace(tag, ",omitempty", "", -1)
}
}
// if is tagged with graphql or json, but is not exported, ignore it
if ok && tag == "-" {
continue
}
objectType, ok := enc.getType(field.Type)
if !ok {
ot, err := enc.buildFieldType(field.Type)
if err != nil {
return nil, NewErrTypeNotRecognizedWithStruct(err, t, field)
}
objectType = ot
enc.registerType(field.Type, ot)
}
// If the tag starts with "!" it is a NonNull type.
if len(tag) > 0 && tag[0] == '!' {
objectType = graphql.NewNonNull(objectType)
tag = tag[1:]
}
resolve := fieldResolve(field)
gqlField := &graphql.Field{
Type: objectType,
Resolve: resolve,
}
// check the field name
fieldName := tag
// if the field name was set by the tag, use it
if fieldName == "" {
// if the field name was not set by the tag
// build the field name by creating a camel case from the struct field name
fieldNameRunes := []rune(field.Name)
if len(tag) > 0 {
fieldNameRunes = []rune(tag)
}
fieldName = toLowerCamelCase(string(fieldNameRunes))
}
gqlField.Name = fieldName
AddField(r, gqlField)
}
return r, nil
}
func (enc *Encoder) FieldOf(t reflect.Type, options ...Option) (graphql.Field, error) {
r := graphql.Field{}
fieldType, err := enc.StructOf(t)
if err != nil {
return graphql.Field{}, err
}
r.Type = fieldType
for _, option := range options {
err = option.Apply(&r)
if err != nil {
return graphql.Field{}, err
}
}
return r, nil
}
func (enc *Encoder) Field(t interface{}, options ...Option) (graphql.Field, error) {
return enc.FieldOf(reflect.TypeOf(t), options...)
}
func (enc *Encoder) ArrayOf(t reflect.Type, options ...Option) (graphql.Type, error) {
if t.Kind() == reflect.Ptr {
// If pointer, get the Type of the pointer
t = t.Elem()
}
var typeBuilt graphql.Type
if cachedType, ok := enc.getType(t); ok {
return graphql.NewList(cachedType), nil
}
if t.Kind() == reflect.Struct {
bt, err := enc.StructOf(t, options...)
if err != nil {
return nil, err
}
typeBuilt = bt
} else {
ttt, err := enc.buildFieldType(t)
if err != nil {
return nil, err
}
typeBuilt = ttt
}
enc.registerType(t, typeBuilt)
return graphql.NewList(typeBuilt), nil
}
func (enc *Encoder) InputObjectFieldMap(t reflect.Type) (graphql.InputObjectConfigFieldMap, error) {
r := graphql.InputObjectConfigFieldMap{}
if t.Kind() == reflect.Ptr {
t = t.Elem()
}
if t.Kind() != reflect.Struct {
return r, fmt.Errorf("cannot build args from a non struct")
}
// Goes field by field of the object.
for i := 0; i < t.NumField(); i++ {
field := t.Field(i)
tag, ok := field.Tag.Lookup("graphql")
// if is tagged with graphql, but is not exported, ignore it
if ok && tag == "-" {
continue
}
objectType, ok := enc.getType(field.Type)
if !ok {
ot, err := enc.buildFieldType(field.Type)
if err != nil {
return nil, NewErrTypeNotRecognizedWithStruct(err, t, field)
}
objectType = ot
enc.registerType(field.Type, ot)
}
// If the tag starts with "!" it is a NonNull type.
if len(tag) > 0 && tag[0] == '!' {
objectType = graphql.NewNonNull(objectType)
tag = tag[1:]
}
inputField := &graphql.InputObjectFieldConfig{
Type: objectType,
}
fieldName := []rune(field.Name)
if len(tag) > 0 {
fieldName = []rune(tag)
}
fieldNameS := toLowerCamelCase(string(fieldName))
r[fieldNameS] = inputField
}
return r, nil
}
func (enc *Encoder) ArgsOf(t reflect.Type) (graphql.FieldConfigArgument, error) {
r := graphql.FieldConfigArgument{}
if t.Kind() == reflect.Ptr {
t = t.Elem()
}
if t.Kind() != reflect.Struct {
return r, fmt.Errorf("cannot build args from a non struct")
}
// Goes field by field of the object.
for i := 0; i < t.NumField(); i++ {
field := t.Field(i)
tag, ok := field.Tag.Lookup("graphql")
// if is tagged with graphql, but is not exported, ignore it
if ok && tag == "-" {
continue
}
objectType, ok := enc.getType(field.Type)
if !ok {
ot, err := enc.buildFieldType(field.Type)
if err != nil {
return nil, NewErrTypeNotRecognizedWithStruct(err, t, field)
}
objectType = ot
enc.registerType(field.Type, ot)
}
// If the tag starts with "!" it is a NonNull type.
if len(tag) > 0 && tag[0] == '!' {
objectType = graphql.NewNonNull(objectType)
tag = tag[1:]
}
graphQLArgument := &graphql.ArgumentConfig{
Type: objectType,
}
fieldName := []rune(field.Name)
if len(tag) > 0 {
fieldName = []rune(tag)
}
fieldNameS := toLowerCamelCase(string(fieldName))
r[fieldNameS] = graphQLArgument
}
return r, nil
}
func (enc *Encoder) getType(t reflect.Type) (graphql.Type, bool) {
name := t.Name()
if t.Kind() == reflect.Ptr {
name = t.Elem().Name()
}
if len(name) > 0 {
gt, ok := enc.types[name]
return gt, ok
}
return nil, false
}
func (enc *Encoder) registerType(t reflect.Type, r graphql.Type) {
name := t.Name()
if t.Kind() == reflect.Ptr {
name = t.Elem().Name()
}
if len(name) > 0 {
enc.types[name] = r
}
}
func Struct(obj interface{}) *graphql.Object {
r, err := DefaultEncoder.Struct(obj)
if err != nil {
panic(err.Error())
}
return r
}
func InputObject(name string, obj interface{}) *graphql.InputObject {
t := reflect.TypeOf(obj)
r, err := DefaultEncoder.InputObjectFieldMap(t)
if err != nil {
panic(err.Error())
}
return graphql.NewInputObject(
graphql.InputObjectConfig{
Name: name,
Fields: r,
},
)
}
// Args Obtain the arguments property of a mutation object
func Args(obj interface{}) graphql.FieldConfigArgument {
r, err := DefaultEncoder.Args(obj)
if err != nil {
panic(err.Error())
}
return r
}
func ArgsOf(t reflect.Type) graphql.FieldConfigArgument {
r, err := DefaultEncoder.ArgsOf(t)
if err != nil {
panic(err.Error())
}
return r
}
func FieldOf(t reflect.Type, options ...Option) (graphql.Field, error) {
return DefaultEncoder.FieldOf(t, options...)
}
func Field(t interface{}, options ...Option) graphql.Field {
r, err := DefaultEncoder.Field(t, options...)
if err != nil {
panic(err.Error())
}
return r
}