protobuf acquaintance

protobuf data format is an efficient, platform-independent, language-independent, scalable, and can be used for continuous data storage system RPC system.

protobuf

protobuf Introduction

ProtobufIs Protocol Buffershort, it is independent of Google Inc. in 2008, a highly efficient open-source platform, language-independent, scalable data formats, as currently Protobuf interface description language specification can be used as the basis for the Go language RPC interface tool.

protobuf use

protobufA data protocol is a language-independent, so we need to write IDL file is then generated by means of a special tool to specify the language of the code to achieve serialization and de-serialization process data.

Development process substantially as follows: preparation of the specified language generated code 2. 1. IDL 3. serialization and deserialization

protobuf grammar

protobuf3 grammar guide

Compiler installation

ptotoc

protobufAgreement with c ++ compiler is written in, download the corresponding version of the operating system according to their own protoccompilers: https://github.com/protocolbuffers/protobuf/releases , after decompression copied to the GOPATH/bindirectory.

protoc-gen-go

Go installation tool generates code language

go get -u github.com/golang/protobuf/protoc-gen-go

Code written in IDL

In protobuf_demo/addressthe new one called directory person.protofile contents are as follows:

// 指定使用protobuf版本

// 此处使用v3版本

syntax = "proto3";

// 包名，通过protoc生成go文件

package address;
// 性别类型

// 枚举类型第一个字段必须为0

enum GenderType {

SECRET = 0;

FEMALE = 1;

MALE = 2;

}
// 人

message Person {

int64 id = 1;

string name = 2;

GenderType gender = 3;

string number = 4;

}
// 联系簿

message ContactBook {

repeated Person persons = 1;

}

```
生成go语言代码
在protobuf_demo/address目录下执行以下命令。
address $ protoc --go_out=. ./person.proto 
此时在当前目录下会生成一个person.pb.go文件，我们的Go语言代码里就是使用这个文件。
在protobuf_demo/main.go文件中：
package main

import (
    "fmt"
    "io/ioutil"

    "github.com/golang/protobuf/proto"

    "github.com/Q1mi/studygo/code_demo/protobuf_demo/address"
)

// protobuf demo

func main() {
    var cb address.ContactBook

    p1 := address.Person{
        Name:   "小王子",
        Gender: address.GenderType_MALE,
        Number: "7878778",
    }
    fmt.Println(p1)
    cb.Persons = append(cb.Persons, &p1)
    // 序列化
    data, err := proto.Marshal(&p1)
    if err != nil {
        fmt.Printf("marshal failed,err:%v\n", err)
        return
    }
    ioutil.WriteFile("./proto.dat", data, 0644)

    data2, err := ioutil.ReadFile("./proto.dat")
    if err != nil {
        fmt.Printf("read file failed, err:%v\n", err)
        return
    }
    var p2 address.Person
    proto.Unmarshal(data2, &p2)
    fmt.Println(p2)
}