forked from grpc-ecosystem/grpc-gateway
-
Notifications
You must be signed in to change notification settings - Fork 0
/
fieldmask.go
165 lines (141 loc) · 4.58 KB
/
fieldmask.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
package runtime
import (
"encoding/json"
"fmt"
"io"
"sort"
"google.golang.org/genproto/protobuf/field_mask"
"google.golang.org/protobuf/proto"
"google.golang.org/protobuf/reflect/protoreflect"
)
func getFieldByName(fields protoreflect.FieldDescriptors, name string) protoreflect.FieldDescriptor {
fd := fields.ByName(protoreflect.Name(name))
if fd != nil {
return fd
}
return fields.ByJSONName(name)
}
// FieldMaskFromRequestBody creates a FieldMask printing all complete paths from the JSON body.
func FieldMaskFromRequestBody(r io.Reader, msg proto.Message) (*field_mask.FieldMask, error) {
fm := &field_mask.FieldMask{}
var root interface{}
if err := json.NewDecoder(r).Decode(&root); err != nil {
if err == io.EOF {
return fm, nil
}
return nil, err
}
queue := []fieldMaskPathItem{{node: root, msg: msg.ProtoReflect()}}
for len(queue) > 0 {
// dequeue an item
item := queue[0]
queue = queue[1:]
m, ok := item.node.(map[string]interface{})
switch {
case ok:
// if the item is an object, then enqueue all of its children
for k, v := range m {
if item.msg == nil {
return nil, fmt.Errorf("JSON structure did not match request type")
}
fd := getFieldByName(item.msg.Descriptor().Fields(), k)
if fd == nil {
return nil, fmt.Errorf("could not find field %q in %q", k, item.msg.Descriptor().FullName())
}
if isDynamicProtoMessage(fd.Message()) {
for _, p := range buildPathsBlindly(k, v) {
newPath := p
if item.path != "" {
newPath = item.path + "." + newPath
}
queue = append(queue, fieldMaskPathItem{path: newPath})
}
continue
}
if isProtobufAnyMessage(fd.Message()) {
_, hasTypeField := v.(map[string]interface{})["@type"]
if hasTypeField {
queue = append(queue, fieldMaskPathItem{path: k})
continue
} else {
return nil, fmt.Errorf("could not find field @type in %q in message %q", k, item.msg.Descriptor().FullName())
}
}
child := fieldMaskPathItem{
node: v,
}
if item.path == "" {
child.path = string(fd.FullName().Name())
} else {
child.path = item.path + "." + string(fd.FullName().Name())
}
switch {
case fd.IsList(), fd.IsMap():
// As per: https://github.com/protocolbuffers/protobuf/blob/master/src/google/protobuf/field_mask.proto#L85-L86
// Do not recurse into repeated fields. The repeated field goes on the end of the path and we stop.
fm.Paths = append(fm.Paths, child.path)
case fd.Message() != nil:
child.msg = item.msg.Get(fd).Message()
fallthrough
default:
queue = append(queue, child)
}
}
case len(item.path) > 0:
// otherwise, it's a leaf node so print its path
fm.Paths = append(fm.Paths, item.path)
}
}
// Sort for deterministic output in the presence
// of repeated fields.
sort.Strings(fm.Paths)
return fm, nil
}
func isProtobufAnyMessage(md protoreflect.MessageDescriptor) bool {
return md != nil && (md.FullName() == "google.protobuf.Any")
}
func isDynamicProtoMessage(md protoreflect.MessageDescriptor) bool {
return md != nil && (md.FullName() == "google.protobuf.Struct" || md.FullName() == "google.protobuf.Value")
}
// buildPathsBlindly does not attempt to match proto field names to the
// json value keys. Instead it relies completely on the structure of
// the unmarshalled json contained within in.
// Returns a slice containing all subpaths with the root at the
// passed in name and json value.
func buildPathsBlindly(name string, in interface{}) []string {
m, ok := in.(map[string]interface{})
if !ok {
return []string{name}
}
var paths []string
queue := []fieldMaskPathItem{{path: name, node: m}}
for len(queue) > 0 {
cur := queue[0]
queue = queue[1:]
m, ok := cur.node.(map[string]interface{})
if !ok {
// This should never happen since we should always check that we only add
// nodes of type map[string]interface{} to the queue.
continue
}
for k, v := range m {
if mi, ok := v.(map[string]interface{}); ok {
queue = append(queue, fieldMaskPathItem{path: cur.path + "." + k, node: mi})
} else {
// This is not a struct, so there are no more levels to descend.
curPath := cur.path + "." + k
paths = append(paths, curPath)
}
}
}
return paths
}
// fieldMaskPathItem stores a in-progress deconstruction of a path for a fieldmask
type fieldMaskPathItem struct {
// the list of prior fields leading up to node connected by dots
path string
// a generic decoded json object the current item to inspect for further path extraction
node interface{}
// parent message
msg protoreflect.Message
}