mpagenko | af80163 | 2020-07-03 10:00:42 +0000 | [diff] [blame] | 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 | } |