测试环境

• ubuntu16.04 64bit
• protocbuf：3.9.1 （支持json转换需>=3.0.0）

协议

syntax = "proto2";

message Person{
	optional string name = 1;
	optional uint32 age = 2;
	optional string address = 3;
}

测试代码

//protobuf >= 3.0.0

#include "person.pb.h"
#include "google/protobuf/stubs/stringpiece.h"
#include "google/protobuf/util/json_util.h"
#include <iostream>

bool proto_to_json(const google::protobuf::Message& message, std::string& json) {
    google::protobuf::util::JsonPrintOptions options;
    // options.add_whitespace = true;
    return MessageToJsonString(message, &json, options).ok();
}

bool json_to_proto(const std::string& json, google::protobuf::Message& message) {
    google::protobuf::util::JsonParseOptions options;
    return JsonStringToMessage(json, &message, options).ok();
}

int main(int argc, char* argv[]){
    std::string person_json;

    Person person;
    person.set_name("hb");
    person.set_age(20);
    person.set_address("sjz");

    if (!proto_to_json(person, person_json)) {
        std::cout << "pb to json failed!" << std::endl;
    }else{
        std::cout << "pb to json:" << person_json << std::endl;
    }

    person.Clear();
    person_json.clear();
    person_json = "{\"name\": \"HB\", \"age\": 22, \"address\": \"SJZ\" }";
    if (!json_to_proto(person_json, person)) {
        std::cout << "json to pb failed!" << std::endl;
    }else{
        std::cout << "json to pb: name:" << person.name() << " age:" << person.age() << " address:" << person.address() << std::endl;
    }
    return 0;
}

编译

• 编译协议

  protoc --cpp_out=. person.proto 
  

• 编译代码

  g++ person.pb.cc demo.cpp -lprotobuf -lpthread -o demo && ./demo
  

运行结果

pb to json:{"name":"hb","age":20,"address":"sjz"}
json to pb: name:HB age:22 address:SJZ