Google.Protobuf工具在C#中的使用方法

第Google.Protobuf工具在C#中的使用方法protobuf是一个语言无关、平台无关的序列化协议，由谷歌开源提供。再加上其高性能、存储占用更小等特点，在云原生的应用中越来越广泛。

在C#中主要有两种方法来使用protobuf协议，nuget包分别为Google.Protobuf和protobuf-net，其中Google.Protobuf由谷歌官方提供。本文简要记录和展示Google.Protobuf的使用方法和特点。

项目资料及文档

项目官网：/protocol-buffershl=zh-cn

github主页：/protocolbuffers/protobuf/

官方文档：/protocol-buffers/docs/overviewhl=zh-cn

该nuget包支持.NETFramework4.5、.NETStandard1.1、.net5等

需要用到的nuget有如下两个：Google.Protobuf、Google.Protobuf.Tools，其中Google.Protobuf是主类库，运行时要用到。Google.Protobuf.Tools提供了命令行工具，用于根据.proto文件转为目标语言的类型，仅开发时使用，运行时不需要。

本次Demo使用的.proto文件内容如下：

syntax="proto3";

optioncc_enable_arenas=true;

packageTccc.Demo.Protobuf;

messageErrorLog{

stringLogID=1;

stringContext=2;

stringStack=3;

}

首先需要根据.proto文件生成目标类型，操作如下：

./tobuf.tools\3.19.1\tools\windows_x64\protoc.exe--csharp_out=./generatedCode./proto/ErrorLto

其中--csharp_out选项是生成C#语言的目标类型，运行protoc.exe-h查看帮助信息，可以看到还支持一下几种选项：

--proto_path=PATH

--cpp_out=OUT_DIRGenerateC++headerandsource.

--csharp_out=OUT_DIRGenerateC#sourcefile.

--java_out=OUT_DIRGenerateJavasourcefile.

--js_out=OUT_DIRGenerateJavaScriptsource.

--kotlin_out=OUT_DIRGenerateKotlinfile.

--objc_out=OUT_DIRGenerateObjective-Cheaderandsource.

--php_out=OUT_DIRGeneratePHPsourcefile.

--python_out=OUT_DIRGeneratePythonsourcefile.

--ruby_out=OUT_DIRGenerateRubysourcefile.

运行上述命令，会根据指定的ErrorLto文件生成ErrorLog.cs文件，文件中就是C#类型ErrorLog。生成的代码中会给此类型增加方法voidWriteTo(CodedOutputStreamoutput)和只读属性Parser，接下来进行序列化和反序列化的关键。

生成的ErrorLog类的完整代码：

//auto-generated

//Generatedbytheprotocolbuffercompiler.DONOTEDIT!

//source:ProtoFiles/ErrorLto

///auto-generated

#pragmawarningdisable1591,0612,3021

#regionDesignergeneratedcode

usingpb=global::Google.Protobuf;

usingpbc=global::Google.Protobuf.Collections;

usingpbr=global::Google.Protobuf.Reflection;

usingscg=global::System.Collections.Generic;

namespaceTccc.Demo.Protobuf{

///summaryHolderforreflectioninformationgeneratedfromProtoFiles/ErrorLto/summary

publicstaticpartialclassErrorLogReflection{

#regionDescriptor

///summaryFiledescriptorforProtoFiles/ErrorLto/summary

publicstaticpbr::FileDescriptorDescriptor{

get{returndescriptor;}

privatestaticpbr::FileDescriptordescriptor;

staticErrorLogReflection(){

byte[]descriptorData=global::System.Convert.FromBase64String(

string.Concat(

"ChlQcm90b0ZpbGVzL0Vycm9yTG9nLnByb3RvEhJUY2NjLkRlbW8uUHJvdG9i",

"dWYiOQoIRXJyb3JMb2cSDQoFTG9nSUQYASABKAkSDwoHQ29udGV4dBgCIAEo",

"CRINCgVTdGFjaxgDIAEoCUID+AEBYgZwcm90bzM="));

descriptor=pbr::FileDescriptor.FromGeneratedCode(descriptorData,

newpbr::FileDescriptor[]{},

newpbr::GeneratedClrTypeInfo(null,null,newpbr::GeneratedClrTypeInfo[]{

newpbr::GeneratedClrTypeInfo(typeof(global::Tccc.Demo.Protobuf.ErrorLog),global::Tccc.Demo.Protobuf.ErrorLog.Parser,new[]{"LogID","Context","Stack"},null,null,null,null)

}));

#endregion

#regionMessages

publicsealedpartialclassErrorLog:pb::IMessageErrorLog

#if!GOOGLE_PROTOBUF_REFSTRUCT_COMPATIBILITY_MODE

,pb::IBufferMessage

#endif

privatestaticreadonlypb::MessageParserErrorLog_parser=newpb::MessageParserErrorLog(()=newErrorLog());

privatepb::UnknownFieldSet_unknownFields;

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicstaticpb::MessageParserErrorLogParser{get{return_parser;}}

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicstaticpbr::MessageDescriptorDescriptor{

get{returnglobal::Tccc.Demo.Protobuf.ErrorLogReflection.Descriptor.MessageTypes[0];}

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

pbr::MessageDescriptorpb::IMessage.Descriptor{

get{returnDescriptor;}

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicErrorLog(){

OnConstruction();

partialvoidOnConstruction();

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicErrorLog(ErrorLogother):this(){

logID_=other.logID_;

context_=other.context_;

stack_=other.stack_;

_unknownFields=pb::UnknownFieldSet.Clone(other._unknownFields);

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicErrorLogClone(){

returnnewErrorLog(this);

///summaryFieldnumberforthe"LogID"field./summary

publicconstintLogIDFieldNumber=1;

privatestringlogID_="";

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicstringLogID{

get{returnlogID_;}

set{

logID_=pb::ProtoPreconditions.CheckNotNull(value,"value");

///summaryFieldnumberforthe"Context"field./summary

publicconstintContextFieldNumber=2;

privatestringcontext_="";

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicstringContext{

get{returncontext_;}

set{

context_=pb::ProtoPreconditions.CheckNotNull(value,"value");

///summaryFieldnumberforthe"Stack"field./summary

publicconstintStackFieldNumber=3;

privatestringstack_="";

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicstringStack{

get{returnstack_;}

set{

stack_=pb::ProtoPreconditions.CheckNotNull(value,"value");

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicoverrideboolEquals(objectother){

returnEquals(otherasErrorLog);

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicboolEquals(ErrorLogother){

if(ReferenceEquals(other,null)){

returnfalse;

if(ReferenceEquals(other,this)){

returntrue;

if(LogID!=other.LogID)returnfalse;

if(Context!=other.Context)returnfalse;

if(Stack!=other.Stack)returnfalse;

returnEquals(_unknownFields,other._unknownFields);

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicoverrideintGetHashCode(){

inthash=1;

if(LogID.Length!=0)hash^=LogID.GetHashCode();

if(Context.Length!=0)hash^=Context.GetHashCode();

if(Stack.Length!=0)hash^=Stack.GetHashCode();

if(_unknownFields!=null){

hash^=_unknownFields.GetHashCode();

returnhash;

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicoverridestringToString(){

returnpb::JsonFormatter.ToDiagnosticString(this);

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicvoidWriteTo(pb::CodedOutputStreamoutput){

#if!GOOGLE_PROTOBUF_REFSTRUCT_COMPATIBILITY_MODE

output.WriteRawMessage(this);

#else

if(LogID.Length!=0){

output.WriteRawTag(10);

output.WriteString(LogID);

if(Context.Length!=0){

output.WriteRawTag(18);

output.WriteString(Context);

if(Stack.Length!=0){

output.WriteRawTag(26);

output.WriteString(Stack);

if(_unknownFields!=null){

_unknownFields.WriteTo(output);

#endif

#if!GOOGLE_PROTOBUF_REFSTRUCT_COMPATIBILITY_MODE

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

voidpb::IBufferMessage.InternalWriteTo(refpb::WriteContextoutput){

if(LogID.Length!=0){

output.WriteRawTag(10);

output.WriteString(LogID);

if(Context.Length!=0){

output.WriteRawTag(18);

output.WriteString(Context);

if(Stack.Length!=0){

output.WriteRawTag(26);

output.WriteString(Stack);

if(_unknownFields!=null){

_unknownFields.WriteTo(refoutput);

#endif

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicintCalculateSize(){

intsize=0;

if(LogID.Length!=0){

size+=1+pb::CodedOutputStream.ComputeStringSize(LogID);

if(Context.Length!=0){

size+=1+pb::CodedOutputStream.ComputeStringSize(Context);

if(Stack.Length!=0){

size+=1+pb::CodedOutputStream.ComputeStringSize(Stack);

if(_unknownFields!=null){

size+=_unknownFields.CalculateSize();

returnsize;

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicvoidMergeFrom(ErrorLogother){

if(other==null){

return;

if(other.LogID.Length!=0){

LogID=other.LogID;

if(other.Context.Length!=0){

Context=other.Context;

if(other.Stack.Length!=0){

Stack=other.Stack;

_unknownFields=pb::UnknownFieldSet.MergeFrom(_unknownFields,other._unknownFields);

[global::System.Diagnostics.DebuggerNonUserCodeAttribute]

[global::System.CodeDom.Compiler.GeneratedCode("protoc",null)]

publicvoidMergeFrom(pb::CodedInputStreaminput){

#if!GOOGLE_PROTOBUF_REFSTRUCT_COMPATIBILITY_MODE

input.ReadRawMessage(this);

#else

uinttag;

while((tag=input.ReadTag())!=0){

switch(tag){

default:

_unknownFields=pb::UnknownFieldSet.MergeFieldFrom(_unknownFields,input);

break;

case10:{

LogID=input.ReadString();

break;

case18:{

Context=input.ReadString();

break;

case26:{

Stack=input.ReadString();

break;