adapters.py 文件源码

def _create_stream(self, max_buffer_size, af, addr, source_ip=None,
            source_port=None):
        # Always connect in plaintext; we'll convert to ssl if necessary
        # after one connection has completed.
        source_port_bind = source_port if isinstance(source_port, int) else 0
        source_ip_bind = source_ip

        socket_obj = socket.socket(af)
        set_close_exec(socket_obj.fileno())
        try:
            stream = IOStream(socket_obj,
                              io_loop=self.io_loop,
                              max_buffer_size=max_buffer_size)

            # connect proxy
            if source_port_bind or source_ip_bind:
                @gen.coroutine
                def _(addr):
                    proxy_headers = get_proxy_headers(source_ip_bind)
                    parsed = urlparse(source_ip_bind)
                    scheme, host, port = parsed.scheme, parsed.hostname, source_port_bind
                    if 'socks' in scheme:
                        r = yield self._negotiate_socks(addr, (source_ip_bind, source_port_bind))
                        raise gen.Return(r)
                    elif scheme in ('http', 'https'):
                        r = yield stream.connect((host, port))
                        if scheme == 'https':
                            yield self._connect_tunnel(stream, addr, proxy_headers)
                        raise gen.Return(r)
                    else:
                        raise AttributeError('Unknown scheme: %s' % scheme)
                return _(addr)
            else:
                return stream.connect(addr)
        except socket.error as e:
            fu = Future()
            fu.set_exception(e)
            return fu