MsgPack + ASIO

2013-06-14

Choi Wonseok

MSGPACK

MessagePack is an efficient binary serialization format.

msgpack C++ API

Data

 #include "msgpack.hpp"
 class cpx {
	double re;
	double im;
 public:
	MSGPACK_DEFINE(re, im);
	...
 };

MSGPACK c++ API

Pack (Serialization)

 cpx data; data.set_re(1.0);
 data.set_im(2.13);

 msgpack::sbuffer sbuf;
 msgpack::pack(sbuf, data);

MSGPACK C++ API

Unpack (Deserialization)

 msgpack::unpacked msg;
 msgpack::unpack(&msg, sbuf.data(), sbuf.size());

 msgpack::object obj = msg.get();

 cpx rdata;
 obj.convert(&rdata);

Boost asio

http://www.boost.org/doc/libs/1_53_0/doc/html/boost_asio.html

Boost.Asio is a cross-platform c++ library for network and low-level I/O programming...

Boost asio anatomy

The io_service represents your program's link to the operating system's I/O services.

boost asio anatomy

The io_service signals to the operating system that it should start an asynchronous connect.

Boost asio anatomy

the io_service dequeues the result of the operation, translates it into an error_code, and then passes it to your completion handler.

Boost asio buffer

buffers can be simply expressed as a tuple consisting of a pointer and a size in bytes.

streams

Many I/O objects in Boost.Asio are stream-oriented. This means that:

There are no message boundaries. The data being transferred is a continuous sequence of bytes.
Read or write operations may transfer fewer bytes than requested. This is referred to as a short read or short write. use: read(), async_read(), write(), async_write().

tcp client skeleton

 #include "boost/asio.hpp" ... using boost::asio::ip::tcp; ... int main(int argc, char *argv[]) {     ...     boost::asio::io_service io_service;     tcp::resolver resolver(io_service);     tcp::resolver::query query(argv[1], argv[2]); // addr, port
     tcp::resolver::iterator endpoint_iter = relover.resolve(query);          tcp::socket socket(io_service);     boost::asio::connect(socket, endpoint_iter);     ...

practice

build your program
and test: mts <ipaddress> <port> <your name> <id> <gpa>

example code

https://github.com/svperbeast/boost_asio_msgpack_ex