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
|
// Copyright (C) MongoDB, Inc. 2017-present.
//
// 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
package bsoncodec
import (
"reflect"
"go.mongodb.org/mongo-driver/bson/bsonoptions"
"go.mongodb.org/mongo-driver/bson/bsonrw"
"go.mongodb.org/mongo-driver/bson/bsontype"
"go.mongodb.org/mongo-driver/bson/primitive"
)
// EmptyInterfaceCodec is the Codec used for interface{} values.
type EmptyInterfaceCodec struct {
DecodeBinaryAsSlice bool
}
var (
defaultEmptyInterfaceCodec = NewEmptyInterfaceCodec()
_ ValueCodec = defaultEmptyInterfaceCodec
_ typeDecoder = defaultEmptyInterfaceCodec
)
// NewEmptyInterfaceCodec returns a EmptyInterfaceCodec with options opts.
func NewEmptyInterfaceCodec(opts ...*bsonoptions.EmptyInterfaceCodecOptions) *EmptyInterfaceCodec {
interfaceOpt := bsonoptions.MergeEmptyInterfaceCodecOptions(opts...)
codec := EmptyInterfaceCodec{}
if interfaceOpt.DecodeBinaryAsSlice != nil {
codec.DecodeBinaryAsSlice = *interfaceOpt.DecodeBinaryAsSlice
}
return &codec
}
// EncodeValue is the ValueEncoderFunc for interface{}.
func (eic EmptyInterfaceCodec) EncodeValue(ec EncodeContext, vw bsonrw.ValueWriter, val reflect.Value) error {
if !val.IsValid() || val.Type() != tEmpty {
return ValueEncoderError{Name: "EmptyInterfaceEncodeValue", Types: []reflect.Type{tEmpty}, Received: val}
}
if val.IsNil() {
return vw.WriteNull()
}
encoder, err := ec.LookupEncoder(val.Elem().Type())
if err != nil {
return err
}
return encoder.EncodeValue(ec, vw, val.Elem())
}
func (eic EmptyInterfaceCodec) getEmptyInterfaceDecodeType(dc DecodeContext, valueType bsontype.Type) (reflect.Type, error) {
isDocument := valueType == bsontype.Type(0) || valueType == bsontype.EmbeddedDocument
if isDocument {
if dc.defaultDocumentType != nil {
// If the bsontype is an embedded document and the DocumentType is set on the DecodeContext, then return
// that type.
return dc.defaultDocumentType, nil
}
if dc.Ancestor != nil {
// Using ancestor information rather than looking up the type map entry forces consistent decoding.
// If we're decoding into a bson.D, subdocuments should also be decoded as bson.D, even if a type map entry
// has been registered.
return dc.Ancestor, nil
}
}
rtype, err := dc.LookupTypeMapEntry(valueType)
if err == nil {
return rtype, nil
}
if isDocument {
// For documents, fallback to looking up a type map entry for bsontype.Type(0) or bsontype.EmbeddedDocument,
// depending on the original valueType.
var lookupType bsontype.Type
switch valueType {
case bsontype.Type(0):
lookupType = bsontype.EmbeddedDocument
case bsontype.EmbeddedDocument:
lookupType = bsontype.Type(0)
}
rtype, err = dc.LookupTypeMapEntry(lookupType)
if err == nil {
return rtype, nil
}
}
return nil, err
}
func (eic EmptyInterfaceCodec) decodeType(dc DecodeContext, vr bsonrw.ValueReader, t reflect.Type) (reflect.Value, error) {
if t != tEmpty {
return emptyValue, ValueDecoderError{Name: "EmptyInterfaceDecodeValue", Types: []reflect.Type{tEmpty}, Received: reflect.Zero(t)}
}
rtype, err := eic.getEmptyInterfaceDecodeType(dc, vr.Type())
if err != nil {
switch vr.Type() {
case bsontype.Null:
return reflect.Zero(t), vr.ReadNull()
default:
return emptyValue, err
}
}
decoder, err := dc.LookupDecoder(rtype)
if err != nil {
return emptyValue, err
}
elem, err := decodeTypeOrValue(decoder, dc, vr, rtype)
if err != nil {
return emptyValue, err
}
if eic.DecodeBinaryAsSlice && rtype == tBinary {
binElem := elem.Interface().(primitive.Binary)
if binElem.Subtype == bsontype.BinaryGeneric || binElem.Subtype == bsontype.BinaryBinaryOld {
elem = reflect.ValueOf(binElem.Data)
}
}
return elem, nil
}
// DecodeValue is the ValueDecoderFunc for interface{}.
func (eic EmptyInterfaceCodec) DecodeValue(dc DecodeContext, vr bsonrw.ValueReader, val reflect.Value) error {
if !val.CanSet() || val.Type() != tEmpty {
return ValueDecoderError{Name: "EmptyInterfaceDecodeValue", Types: []reflect.Type{tEmpty}, Received: val}
}
elem, err := eic.decodeType(dc, vr, val.Type())
if err != nil {
return err
}
val.Set(elem)
return nil
}
|
