tornadoを使ったPeercastのAtom構造解析

main.py

#!/usr/bin/python3
# vim: set sw=4 sts=4 ts=4 expandtab:

from tornado.tcpserver import TCPServer
from tornado.iostream import StreamClosedError
from tornado import gen
import tornado.ioloop

import struct


address_state = dict()


class PCPServer(TCPServer):

    """PCPパケットを読みとって単純にその内容を表示するサーバーです。"""

    @gen.coroutine
    def handle_stream(self, stream, address):
        """パケットを受けとった時に処理する関数です。"""
        while True:
            try:
                command = yield stream.read_bytes(4)
                command = command.decode("utf-8")
                print("PCP: %s" % command)
                length = yield stream.read_bytes(4)
                length = struct.unpack("<1I", length)
                if length[0] > 0x7fffffff:  # HAS CHILD
                    length = length[0] & 0x7fffffff  # 符号反転
                    print("CHILD: %s" % length)
                else:
                    length = length[0]
                    print("LEN: %s" % length)
                    data = yield stream.read_bytes(length)
                    print("DATA READ")
            except StreamClosedError:
                break


if __name__ == "__main__":
    server = PCPServer()
    server.bind(7146)
    server.start(0)
    tornado.ioloop.IOLoop.current().start()