golang使用protobuf简易教程

参考文档：https://blog.csdn.net/qq_15437667/article/details/78425151

1、安装protobuf

# 去github.com/golang/protobuf下载源码包，
# 拷贝到 $GOPATH/src/github.com/golang/protobuf

$ cd $GOPATH/src/github.com/golang/protobuf
$ go install

# 安装 protobuf-compiler
$ sudo apt-get install protobuf-compiler

2、使用protobuf

1. 编写example.proto示例文件

// example.proto
syntax = "proto2";
package example;

message LD
{
    required uint32 ip = 1;
}

message Set
{
	required uint32 id	=1;
	required string name	=2;
	repeated LD ld_list	=3;
}

2. 编译生成.pb.go文件

protoc --go_out=./ example.proto

生成的 example.pb.go文件

// Code generated by protoc-gen-go. DO NOT EDIT.
// source: example.proto

package example

import proto "github.com/golang/protobuf/proto"
import fmt "fmt"
import math "math"

// Reference imports to suppress errors if they are not otherwise used.
var _ = proto.Marshal
var _ = fmt.Errorf
var _ = math.Inf

// This is a compile-time assertion to ensure that this generated file
// is compatible with the proto package it is being compiled against.
// A compilation error at this line likely means your copy of the
// proto package needs to be updated.
const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package

type LD struct {
	Ip                   *uint32  `protobuf:"varint,1,req,name=ip" json:"ip,omitempty"`
	XXX_NoUnkeyedLiteral struct{} `json:"-"`
	XXX_unrecognized     []byte   `json:"-"`
	XXX_sizecache        int32    `json:"-"`
}

func (m *LD) Reset()         { *m = LD{} }
func (m *LD) String() string { return proto.CompactTextString(m) }
func (*LD) ProtoMessage()    {}
func (*LD) Descriptor() ([]byte, []int) {
	return fileDescriptor_example_c8b6363476e787b3, []int{0}
}
func (m *LD) XXX_Unmarshal(b []byte) error {
	return xxx_messageInfo_LD.Unmarshal(m, b)
}
func (m *LD) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
	return xxx_messageInfo_LD.Marshal(b, m, deterministic)
}
func (dst *LD) XXX_Merge(src proto.Message) {
	xxx_messageInfo_LD.Merge(dst, src)
}
func (m *LD) XXX_Size() int {
	return xxx_messageInfo_LD.Size(m)
}
func (m *LD) XXX_DiscardUnknown() {
	xxx_messageInfo_LD.DiscardUnknown(m)
}

var xxx_messageInfo_LD proto.InternalMessageInfo

func (m *LD) GetIp() uint32 {
	if m != nil && m.Ip != nil {
		return *m.Ip
	}
	return 0
}

type Set struct {
	Id                   *uint32  `protobuf:"varint,1,req,name=id" json:"id,omitempty"`
	Name                 *string  `protobuf:"bytes,2,req,name=name" json:"name,omitempty"`
	LdList               []*LD    `protobuf:"bytes,3,rep,name=ld_list" json:"ld_list,omitempty"`
	XXX_NoUnkeyedLiteral struct{} `json:"-"`
	XXX_unrecognized     []byte   `json:"-"`
	XXX_sizecache        int32    `json:"-"`
}

func (m *Set) Reset()         { *m = Set{} }
func (m *Set) String() string { return proto.CompactTextString(m) }
func (*Set) ProtoMessage()    {}
func (*Set) Descriptor() ([]byte, []int) {
	return fileDescriptor_example_c8b6363476e787b3, []int{1}
}
func (m *Set) XXX_Unmarshal(b []byte) error {
	return xxx_messageInfo_Set.Unmarshal(m, b)
}
func (m *Set) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
	return xxx_messageInfo_Set.Marshal(b, m, deterministic)
}
func (dst *Set) XXX_Merge(src proto.Message) {
	xxx_messageInfo_Set.Merge(dst, src)
}
func (m *Set) XXX_Size() int {
	return xxx_messageInfo_Set.Size(m)
}
func (m *Set) XXX_DiscardUnknown() {
	xxx_messageInfo_Set.DiscardUnknown(m)
}

var xxx_messageInfo_Set proto.InternalMessageInfo

func (m *Set) GetId() uint32 {
	if m != nil && m.Id != nil {
		return *m.Id
	}
	return 0
}

func (m *Set) GetName() string {
	if m != nil && m.Name != nil {
		return *m.Name
	}
	return ""
}

func (m *Set) GetLdList() []*LD {
	if m != nil {
		return m.LdList
	}
	return nil
}

func init() {
	proto.RegisterType((*LD)(nil), "example.LD")
	proto.RegisterType((*Set)(nil), "example.Set")
}

func init() { proto.RegisterFile("example.proto", fileDescriptor_example_c8b6363476e787b3) }

var fileDescriptor_example_c8b6363476e787b3 = []byte{
	// 109 bytes of a gzipped FileDescriptorProto
	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x09, 0x6e, 0x88, 0x02, 0xff, 0xe2, 0xe2, 0x4d, 0xad, 0x48, 0xcc,
	0x2d, 0xc8, 0x49, 0xd5, 0x2b, 0x28, 0xca, 0x2f, 0xc9, 0x17, 0x62, 0x87, 0x72, 0x95, 0x04, 0xb8,
	0x98, 0x7c, 0x5c, 0x84, 0xb8, 0xb8, 0x98, 0x32, 0x0b, 0x24, 0x18, 0x15, 0x98, 0x34, 0x78, 0x95,
	0x6c, 0xb9, 0x98, 0x83, 0x53, 0x4b, 0xc0, 0x42, 0x29, 0x10, 0x21, 0x21, 0x1e, 0x2e, 0x96, 0xbc,
	0xc4, 0xdc, 0x54, 0x09, 0x26, 0x20, 0x8f, 0x53, 0x48, 0x86, 0x8b, 0x3d, 0x27, 0x25, 0x3e, 0x27,
	0xb3, 0xb8, 0x44, 0x82, 0x59, 0x81, 0x59, 0x83, 0xdb, 0x88, 0x5b, 0x0f, 0x66, 0xb8, 0x8f, 0x0b,
	0x20, 0x00, 0x00, 0xff, 0xff, 0x2d, 0xbd, 0x0b, 0xe7, 0x69, 0x00, 0x00, 0x00,
}

特别注意: 生成的文件中的package是example, 那么文件必须放在example文件夹下! 不然会报错: “can’t load package: package example

3、写一个测试程序

package main

import (
	"fmt"
	t "./example"
	"github.com/golang/protobuf/proto"
)

func main() {
	var hw t.Set
	var ld t.LD

	ld = t.LD {
		Ip: proto.Uint32(666),
	}

	hw = t.Set {
		Id: proto.Uint32(1),
		Name: proto.String("hello"),
	}

	mData, err := proto.Marshal(&hw)

	if err != nil {
		fmt.Println("Error1:", err)
		return
	}

	var umData t.Set
	err = proto.Unmarshal(mData, &umData)

	if err != nil {
		fmt.Println("Error2:", err)
		return
	}

	fmt.Println(*umData.Id, " ", *umData.Name, " ", *ld.Ip)
}

4、编译运行

$ go build main.go
$ ./main
1   hello   666