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Protobuf-RPC for C++

Install

Install CMake and VS2010(Windows)/gcc(Unix)
cd ${protorpc_root}/protobuf and build with cmake

Add xml support (with `--cxx_out` option):

New API for message:

// Parse a protocol buffer contained in a string.
bool ParseFromXmlString(const string& data);
// Like ParseFromXmlString(), but accepts messages that are missing
// required fields.
bool ParsePartialFromXmlString(const string& data);

// Serialize the message and store it in the given string.  All required
// fields must be set.
bool SerializeToXmlString(string* output) const;
// Like SerializeToXmlString(), but allows missing required fields.
bool SerializePartialToXmlString(string* output) const;

Here is the simple code(${protorpc_root}/protobuf/src/google/protobuf/xml/example/xmltest.cc):

#include <stdio.h>

#include "./xml.pb/XmlTest.pb.h"

int main() {
	google::protobuf::xml::PbXmlTest pb1;
	google::protobuf::xml::PbXmlTest pb2;
	
	pb1.set_b(true);
	pb1.set_i(1001);
	pb1.set_f(0.123f);
	pb1.set_e(google::protobuf::xml::PB_VALUE_TYPE_INT);
	pb1.mutable_m()->set_b(false);
	pb1.mutable_m()->set_i(145);
	
	std::string xmlString;
	bool rv1 = pb1.SerializeToXmlString(&xmlString);
	printf("pb1 xml:\n%s\n", xmlString.c_str());
	
	bool b = pb2.ParseFromXmlString(xmlString);
	printf("pb2 dbg string:\n%s\n", pb2.DebugString().c_str());
	
	return 0;
}

Implement `Protobuf-RPC` (with `--cxx_out` option):

C++ use the same protocol as Go, so we can communication with C++ and Go with Protobuf-RPC.

Here is a simple proto file(${protorpc_root}/protobuf/src/google/protobuf/rpc/service.pb):

package service;

option cc_generic_services = true;
option java_generic_services = true;
option py_generic_services = true;

message EchoRequest {
	optional string msg = 1;
}

message EchoResponse {
	optional string msg = 1;
}

service EchoService {
	rpc echo (EchoRequest) returns (EchoResponse);
}

service EchoServiceA {
	rpc echo (EchoRequest) returns (EchoResponse);
}

service EchoServiceB {
	rpc echo (EchoRequest) returns (EchoResponse);
}

Then use new protoc with --cxx_out option to generate "arith.pb.{h|cc}" file(include rpc stub):

${protorpc_root}/protobuf/bin/protoc --cxx_out=. echo.proto

The server calls (for TCP service):

#include "echo.pb.h"

class EchoService: public service::EchoService {
public:
	inline EchoService() {}
	virtual ~EchoService() {}

	virtual const google::protobuf::rpc::Error Echo(
		const service::EchoRequest* request,
		service::EchoResponse* response
	) {
		response->set_msg(request->msg());
		return google::protobuf::rpc::Error::Nil();
	}
};

int main() {
	google::protobuf::rpc::Server server;

	server.AddService(new EchoService, true);

	server.Serve(9527);
}

At this point, clients can see a service EchoService with methods EchoService.Echo. To invoke one, a client first dials the server:

#include <google/protobuf/rpc/rpc_server.h>
#include <google/protobuf/rpc/rpc_client.h>

#include "arith.pb.h"

int main() {
	google::protobuf::rpc::Client client("127.0.0.1", 9527);
	
	service::EchoService::Stub echoStub(&client);

	service::EchoRequest echoArgs;
	service::EchoResponse echoReply;
	google::protobuf::rpc::Error err;

	// EchoService.echo
	echoArgs.set_msg("Hello Protobuf-RPC!");
	err = echoStub.echo(&echoArgs, &echoReply);
	if(!err.IsNil()) {
		fprintf(stderr, "echoStub.echo: %s\n", err.String().c_str());
		return -1;
	}
	if(echoReply.msg() != echoArgs.msg()) {
		fprintf(stderr, "echoStub.echo: expected = \"%s\", got = \"%s\"\n",
			echoArgs.msg().c_str(), echoReply.msg().c_str()
		);
		return -1;
	}

	// EchoService.echo: Use Client
	echoArgs.set_msg("Hello Protobuf-RPC!");
	err = client.CallMethod("EchoService.Echo", &echoArgs, &echoReply);
	if(!err.IsNil()) {
		fprintf(stderr, "EchoService.echo: %s\n", err.String().c_str());
		return -1;
	}
	if(echoReply.msg() != echoArgs.msg()) {
		fprintf(stderr, "EchoService.echo: expected = \"%s\", got = \"%s\"\n",
			echoArgs.msg().c_str(), echoReply.msg().c_str()
		);
		return -1;
	}

	return 0;
}