Using the profile read and write protobuf

Using the profile read and write protobuf

1, the preparation of proto file protobuf

Often used in the program configuration file, and the use protobuf can easily read and write the configuration file.
Write your good protobuf of proto file

syntax = "proto3";
package msgType;

enum EnumTest
{
    TEST0 = 0x00;
    TEST1 = 0x01;
    TEST2 = 0x02;
    TEST3 = 0x03;
}

message ProtoTestSub
{
    int32 test1 = 1;
    string test2 = 2;
}

message ProtoTest
{
    int32 int32_test = 1;
    string str_test = 2;
    repeated double dou_test = 3;
    repeated ProtoTestSub sub_test = 4;
    EnumTest eunm_test = 5;
    bytes bytes_test = 6;
}

2, generates the corresponding source file

root@root:/root/protobuf# protoc --cpp_out=./ ./test.proto.proto
root@root:/root/protobuf# ls
a.out  include  mybuild  protobuf_main.cpp  test.pb.cc  test.pb.h  test.proto

3, the sample program (configuration file read and write)

#include <iostream>
#include <vector>
#include <algorithm>

#include "test.pb.h"
#include <google/protobuf/text_format.h>
#include <google/protobuf/io/zero_copy_stream_impl.h>

#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <string>
#include <fstream>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>

int main(void )
{
    //1、序列化 填写基本的配置项
    msgType:: ProtoTest cls_proto_test1;
    cls_proto_test1.set_int32_test(123);
    cls_proto_test1.set_str_test("wanxuexiang");
    cls_proto_test1.add_dou_test(56.023);
    cls_proto_test1.add_dou_test(78.023);
    msgType:: ProtoTestSub * pcls_temp = cls_proto_test1.add_sub_test();
    pcls_temp->set_test1(12);
    pcls_temp->set_test2("zxcvbnm");
    pcls_temp = cls_proto_test1.add_sub_test();
    pcls_temp->set_test1(34);
    pcls_temp->set_test2("asdfghjkl");
    cls_proto_test1.set_eunm_test(msgType::TEST0);
    //protobuf调试打印函数 打印成字符串
    cls_proto_test1.PrintDebugString();
    //2、将配置写入文件之中
    std::string str_proto_test1;
    google::protobuf::TextFormat::PrintToString(cls_proto_test1, &str_proto_test1);
    std::ofstream file_proto_test1;
    file_proto_test1.open("file_proto_test1.cfg", std::ios::out| std:: ios_base::ate);

    if (!file_proto_test1.is_open())
    {
        fprintf(stderr, "open file_proto_test1.cfg fail\n");
        return -1;
    }
    file_proto_test1 << str_proto_test1;
    file_proto_test1.flush();
    file_proto_test1.close();
    system("cat file_proto_test1.cfg");
    //2、从配置文件中读取数据
    int fd = open("file_proto_test1.cfg", O_RDONLY);
    if (fd < 0)
    {
        printf("file_proto_test1.cfg:%s \n",strerror(errno));
        return false;
    }
    google::protobuf::io::FileInputStream fileInput(fd);
    fileInput.SetCloseOnDelete(true);
    msgType:: ProtoTest cls_proto_test2;;
    google::protobuf::TextFormat::Parse(&fileInput, &cls_proto_test2);
    //protobuf调试打印函数 打印成字符串
    cls_proto_test2.PrintDebugString();
    msgType:: ProtoTestSub cls_temp ;
    for(int i = 0;i < cls_proto_test2.sub_test_size();i++)
    {
        cls_temp = cls_proto_test2.sub_test(i);
        cls_temp.PrintDebugString();
    }
    while(1)
    {
        sleep(1);
    }       
    return 0;
}

4, operating results

root@ubuntu:/wan/protobuf# ./a.out 
int32_test: 123
str_test: "wanxuexiang"
dou_test: 56.023
dou_test: 78.023
sub_test {
  test1: 12
  test2: "zxcvbnm"
}
sub_test {
  test1: 34
  test2: "asdfghjkl"
}
int32_test: 123
str_test: "wanxuexiang"
dou_test: 56.023
dou_test: 78.023
sub_test {
  test1: 12
  test2: "zxcvbnm"
}
sub_test {
  test1: 34
  test2: "asdfghjkl"
}
int32_test: 123
str_test: "wanxuexiang"
dou_test: 56.023
dou_test: 78.023
sub_test {
  test1: 12
  test2: "zxcvbnm"
}
sub_test {
  test1: 34
  test2: "asdfghjkl"
}
test1: 12
test2: "zxcvbnm"
test1: 34
test2: "asdfghjkl"
^C
root@ubuntu:/wan/protobuf# ls
a.out  file_proto_test1.cfg  include  mybuild  protobuf_main.cpp  test.pb.cc  test.pb.h  test.proto
root@ubuntu:/wan/protobuf# cat file_proto_test1.cfg 
int32_test: 123
str_test: "wanxuexiang"
dou_test: 56.023
dou_test: 78.023
sub_test {
  test1: 12
  test2: "zxcvbnm"
}
sub_test {
  test1: 34
  test2: "asdfghjkl"
}