websocket.py 文件源码

def __init__(self, io_loop, request, on_message_callback=None,
                 compression_options=None):
        self.compression_options = compression_options
        self.connect_future = TracebackFuture()
        self.protocol = None
        self.read_future = None
        self.read_queue = collections.deque()
        self.key = base64.b64encode(os.urandom(16))
        self._on_message_callback = on_message_callback
        self.close_code = self.close_reason = None

        scheme, sep, rest = request.url.partition(':')
        scheme = {'ws': 'http', 'wss': 'https'}[scheme]
        request.url = scheme + sep + rest
        request.headers.update({
            'Upgrade': 'websocket',
            'Connection': 'Upgrade',
            'Sec-WebSocket-Key': self.key,
            'Sec-WebSocket-Version': '13',
        })
        if self.compression_options is not None:
            # Always offer to let the server set our max_wbits (and even though
            # we don't offer it, we will accept a client_no_context_takeover
            # from the server).
            # TODO: set server parameters for deflate extension
            # if requested in self.compression_options.
            request.headers['Sec-WebSocket-Extensions'] = (
                'permessage-deflate; client_max_window_bits')

        self.tcp_client = TCPClient(io_loop=io_loop)
        super(WebSocketClientConnection, self).__init__(
            io_loop, None, request, lambda: None, self._on_http_response,
            104857600, self.tcp_client, 65536, 104857600)