1 // Copyright 2019 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4 5 // Package proto provides functionality for handling protocol buffer messages.
6 // In particular, it provides marshaling and unmarshaling between a protobuf
7 // message and the binary wire format.
8 //
9 // See https://developers.google.com/protocol-buffers/docs/gotutorial for
10 // more information.
11 //
12 // Deprecated: Use the "google.golang.org/protobuf/proto" package instead.
13 package proto
14 15 import (
16 protoV2 "google.golang.org/protobuf/proto"
17 "google.golang.org/protobuf/reflect/protoreflect"
18 "google.golang.org/protobuf/runtime/protoiface"
19 "google.golang.org/protobuf/runtime/protoimpl"
20 )
21 22 const (
23 ProtoPackageIsVersion1 = true
24 ProtoPackageIsVersion2 = true
25 ProtoPackageIsVersion3 = true
26 ProtoPackageIsVersion4 = true
27 )
28 29 // GeneratedEnum is any enum type generated by protoc-gen-go
30 // which is a named int32 kind.
31 // This type exists for documentation purposes.
32 type GeneratedEnum interface{}
33 34 // GeneratedMessage is any message type generated by protoc-gen-go
35 // which is a pointer to a named struct kind.
36 // This type exists for documentation purposes.
37 type GeneratedMessage interface{}
38 39 // Message is a protocol buffer message.
40 //
41 // This is the v1 version of the message interface and is marginally better
42 // than an empty interface as it lacks any method to programatically interact
43 // with the contents of the message.
44 //
45 // A v2 message is declared in "google.golang.org/protobuf/proto".Message and
46 // exposes protobuf reflection as a first-class feature of the interface.
47 //
48 // To convert a v1 message to a v2 message, use the MessageV2 function.
49 // To convert a v2 message to a v1 message, use the MessageV1 function.
50 type Message = protoiface.MessageV1
51 52 // MessageV1 converts either a v1 or v2 message to a v1 message.
53 // It returns nil if m is nil.
54 func MessageV1(m GeneratedMessage) protoiface.MessageV1 {
55 return protoimpl.X.ProtoMessageV1Of(m)
56 }
57 58 // MessageV2 converts either a v1 or v2 message to a v2 message.
59 // It returns nil if m is nil.
60 func MessageV2(m GeneratedMessage) protoV2.Message {
61 return protoimpl.X.ProtoMessageV2Of(m)
62 }
63 64 // MessageReflect returns a reflective view for a message.
65 // It returns nil if m is nil.
66 func MessageReflect(m Message) protoreflect.Message {
67 return protoimpl.X.MessageOf(m)
68 }
69 70 // Marshaler is implemented by messages that can marshal themselves.
71 // This interface is used by the following functions: Size, Marshal,
72 // Buffer.Marshal, and Buffer.EncodeMessage.
73 //
74 // Deprecated: Do not implement.
75 type Marshaler interface {
76 // Marshal formats the encoded bytes of the message.
77 // It should be deterministic and emit valid protobuf wire data.
78 // The caller takes ownership of the returned buffer.
79 Marshal() ([]byte, error)
80 }
81 82 // Unmarshaler is implemented by messages that can unmarshal themselves.
83 // This interface is used by the following functions: Unmarshal, UnmarshalMerge,
84 // Buffer.Unmarshal, Buffer.DecodeMessage, and Buffer.DecodeGroup.
85 //
86 // Deprecated: Do not implement.
87 type Unmarshaler interface {
88 // Unmarshal parses the encoded bytes of the protobuf wire input.
89 // The provided buffer is only valid for during method call.
90 // It should not reset the receiver message.
91 Unmarshal([]byte) error
92 }
93 94 // Merger is implemented by messages that can merge themselves.
95 // This interface is used by the following functions: Clone and Merge.
96 //
97 // Deprecated: Do not implement.
98 type Merger interface {
99 // Merge merges the contents of src into the receiver message.
100 // It clones all data structures in src such that it aliases no mutable
101 // memory referenced by src.
102 Merge(src Message)
103 }
104 105 // RequiredNotSetError is an error type returned when
106 // marshaling or unmarshaling a message with missing required fields.
107 type RequiredNotSetError struct {
108 err error
109 }
110 111 func (e *RequiredNotSetError) Error() string {
112 if e.err != nil {
113 return e.err.Error()
114 }
115 return "proto: required field not set"
116 }
117 func (e *RequiredNotSetError) RequiredNotSet() bool {
118 return true
119 }
120 121 func checkRequiredNotSet(m protoV2.Message) error {
122 if err := protoV2.CheckInitialized(m); err != nil {
123 return &RequiredNotSetError{err: err}
124 }
125 return nil
126 }
127 128 // Clone returns a deep copy of src.
129 func Clone(src Message) Message {
130 return MessageV1(protoV2.Clone(MessageV2(src)))
131 }
132 133 // Merge merges src into dst, which must be messages of the same type.
134 //
135 // Populated scalar fields in src are copied to dst, while populated
136 // singular messages in src are merged into dst by recursively calling Merge.
137 // The elements of every list field in src is appended to the corresponded
138 // list fields in dst. The entries of every map field in src is copied into
139 // the corresponding map field in dst, possibly replacing existing entries.
140 // The unknown fields of src are appended to the unknown fields of dst.
141 func Merge(dst, src Message) {
142 protoV2.Merge(MessageV2(dst), MessageV2(src))
143 }
144 145 // Equal reports whether two messages are equal.
146 // If two messages marshal to the same bytes under deterministic serialization,
147 // then Equal is guaranteed to report true.
148 //
149 // Two messages are equal if they are the same protobuf message type,
150 // have the same set of populated known and extension field values,
151 // and the same set of unknown fields values.
152 //
153 // Scalar values are compared with the equivalent of the == operator in Go,
154 // except bytes values which are compared using bytes.Equal and
155 // floating point values which specially treat NaNs as equal.
156 // Message values are compared by recursively calling Equal.
157 // Lists are equal if each element value is also equal.
158 // Maps are equal if they have the same set of keys, where the pair of values
159 // for each key is also equal.
160 func Equal(x, y Message) bool {
161 return protoV2.Equal(MessageV2(x), MessageV2(y))
162 }
163 164 func isMessageSet(md protoreflect.MessageDescriptor) bool {
165 ms, ok := md.(interface{ IsMessageSet() bool })
166 return ok && ms.IsMessageSet()
167 }
168