C/C++ protobuf与json互转

1. 测试环境

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

2. 协议

   syntax = "proto2";
   
   message Person{
   	optional string name = 1;
   	optional uint32 age = 2;
   	optional string address = 3;
   }
   
   

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 
   
   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;
   }
   
   

4. 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
     

5. 运行结果

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