-
Notifications
You must be signed in to change notification settings - Fork 0
/
jsonpb.go
206 lines (187 loc) · 5.89 KB
/
jsonpb.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
// Copyright (c) 2022 Gobalsky Labs Limited
//
// Use of this software is governed by the Business Source License included
// in the LICENSE.ZETA file and at https://www.mariadb.com/bsl11.
//
// Change Date: 18 months from the later of the date of the first publicly
// available Distribution of this version of the repository, and 25 June 2022.
//
// On the date above, in accordance with the Business Source License, use
// of this software will be governed by version 3 or later of the GNU General
// Public License.
package rest
import (
"bytes"
"encoding/json"
"fmt"
"io"
"reflect"
"github.com/golang/protobuf/jsonpb"
"github.com/golang/protobuf/proto"
"github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
)
// JSONPb is a runtime.Marshaler which marshals/unmarshals into/from.
type JSONPb jsonpb.Marshaler
// ContentType always returns "application/json".
func (*JSONPb) ContentType(interface{}) string {
return "application/json"
}
// Marshal marshals "v" into JSON.
func (j *JSONPb) Marshal(v interface{}) ([]byte, error) {
if _, ok := v.(proto.Message); !ok {
return j.marshalNonProtoField(v)
}
var buf bytes.Buffer
if err := j.marshalTo(&buf, v); err != nil {
return nil, err
}
return buf.Bytes(), nil
}
func (j *JSONPb) marshalTo(w io.Writer, v interface{}) error {
p, ok := v.(proto.Message)
if !ok {
buf, err := j.marshalNonProtoField(v)
if err != nil {
return err
}
_, err = w.Write(buf)
return err
}
return (*jsonpb.Marshaler)(j).Marshal(w, p)
}
// marshalNonProto marshals a non-message field of a protobuf message.
// This function does not correctly marshals arbitrary data structure into JSON,
// but it is only capable of marshaling non-message field values of protobuf,
// i.e. primitive types, enums; pointers to primitives or enums; maps from
// integer/string types to primitives/enums/pointers to messages.
func (j *JSONPb) marshalNonProtoField(v interface{}) ([]byte, error) {
rv := reflect.ValueOf(v)
for rv.Kind() == reflect.Ptr {
if rv.IsNil() {
return []byte("null"), nil
}
rv = rv.Elem()
}
if rv.Kind() == reflect.Map {
m := make(map[string]*json.RawMessage)
for _, k := range rv.MapKeys() {
buf, err := j.Marshal(rv.MapIndex(k).Interface())
if err != nil {
return nil, err
}
m[fmt.Sprintf("%v", k.Interface())] = (*json.RawMessage)(&buf)
}
if j.Indent != "" {
return json.MarshalIndent(m, "", j.Indent)
}
return json.Marshal(m)
}
if enum, ok := rv.Interface().(protoEnum); ok && !j.EnumsAsInts {
return json.Marshal(enum.String())
}
return json.Marshal(rv.Interface())
}
// Unmarshal unmarshals JSON "data" into "v".
// Currently it can only marshal proto.Message.
func (j *JSONPb) Unmarshal(data []byte, v interface{}) error {
return unmarshalJSONPb(data, v)
}
// NewDecoder returns a runtime.Decoder which reads JSON stream from "r".
func (j *JSONPb) NewDecoder(r io.Reader) runtime.Decoder {
d := json.NewDecoder(r)
return runtime.DecoderFunc(func(v interface{}) error { return decodeJSONPb(d, v) })
}
// NewEncoder returns an Encoder which writes JSON stream into "w".
func (j *JSONPb) NewEncoder(w io.Writer) runtime.Encoder {
return runtime.EncoderFunc(func(v interface{}) error { return j.marshalTo(w, v) })
}
func unmarshalJSONPb(data []byte, v interface{}) error {
d := json.NewDecoder(bytes.NewReader(data))
return decodeJSONPb(d, v)
}
func decodeJSONPb(d *json.Decoder, v interface{}) error {
p, ok := v.(proto.Message)
if !ok {
return decodeNonProtoField(d, v)
}
unmarshaler := &jsonpb.Unmarshaler{AllowUnknownFields: true}
return unmarshaler.UnmarshalNext(d, p)
}
func decodeNonProtoField(d *json.Decoder, v interface{}) error {
rv := reflect.ValueOf(v)
if rv.Kind() != reflect.Ptr {
return fmt.Errorf("%T is not a pointer", v)
}
for rv.Kind() == reflect.Ptr {
if rv.IsNil() {
rv.Set(reflect.New(rv.Type().Elem()))
}
if rv.Type().ConvertibleTo(typeProtoMessage) {
unmarshaler := &jsonpb.Unmarshaler{AllowUnknownFields: true}
return unmarshaler.UnmarshalNext(d, rv.Interface().(proto.Message))
}
rv = rv.Elem()
}
if rv.Kind() == reflect.Map {
if rv.IsNil() {
rv.Set(reflect.MakeMap(rv.Type()))
}
conv, ok := convFromType[rv.Type().Key().Kind()]
if !ok {
return fmt.Errorf("unsupported type of map field key: %v", rv.Type().Key())
}
m := make(map[string]*json.RawMessage)
if err := d.Decode(&m); err != nil {
return err
}
for k, v := range m {
result := conv.Call([]reflect.Value{reflect.ValueOf(k)})
if err := result[1].Interface(); err != nil {
return err.(error)
}
bk := result[0]
bv := reflect.New(rv.Type().Elem())
if err := unmarshalJSONPb(*v, bv.Interface()); err != nil {
return err
}
rv.SetMapIndex(bk, bv.Elem())
}
return nil
}
if _, ok := rv.Interface().(protoEnum); ok {
var repr interface{}
if err := d.Decode(&repr); err != nil {
return err
}
switch repr := repr.(type) {
case string:
return fmt.Errorf("unmarshaling of symbolic enum %s not supported: %T", repr, rv.Interface())
case float64:
rv.Set(reflect.ValueOf(int32(repr)).Convert(rv.Type()))
return nil
default:
return fmt.Errorf("cannot assign %#v into Go type %T", repr, rv.Interface())
}
}
return d.Decode(v)
}
type protoEnum interface {
fmt.Stringer
EnumDescriptor() ([]byte, []int)
}
var typeProtoMessage = reflect.TypeOf((*proto.Message)(nil)).Elem()
// Delimiter for newline encoded JSON streams.
func (j *JSONPb) Delimiter() []byte {
return []byte("\n")
}
var convFromType = map[reflect.Kind]reflect.Value{
reflect.String: reflect.ValueOf(runtime.String),
reflect.Bool: reflect.ValueOf(runtime.Bool),
reflect.Float64: reflect.ValueOf(runtime.Float64),
reflect.Float32: reflect.ValueOf(runtime.Float32),
reflect.Int64: reflect.ValueOf(runtime.Int64),
reflect.Int32: reflect.ValueOf(runtime.Int32),
reflect.Uint64: reflect.ValueOf(runtime.Uint64),
reflect.Uint32: reflect.ValueOf(runtime.Uint32),
reflect.Slice: reflect.ValueOf(runtime.Bytes),
}