async_gevent_uwsgi.py 文件源码

def wait(self):
        """Waits and returns received messages.
        If running in compatibility mode for older uWSGI versions,
        it also sends messages that have been queued by send().
        A return value of None means that connection was closed.
        This must be called repeatedly. For uWSGI < 2.1.x it must
        be called from the main greenlet."""
        while True:
            if self._req_ctx is not None:
                try:
                    msg = uwsgi.websocket_recv(request_context=self._req_ctx)
                except IOError:  # connection closed
                    return None
                return self._decode_received(msg)
            else:
                # we wake up at least every 3 seconds to let uWSGI
                # do its ping/ponging
                event_set = self._event.wait(timeout=3)
                if event_set:
                    self._event.clear()
                    # maybe there is something to send
                    msgs = []
                    while True:
                        try:
                            msgs.append(self._send_queue.get(block=False))
                        except gevent.queue.Empty:
                            break
                    for msg in msgs:
                        self._send(msg)
                # maybe there is something to receive, if not, at least
                # ensure uWSGI does its ping/ponging
                try:
                    msg = uwsgi.websocket_recv_nb()
                except IOError:  # connection closed
                    self._select_greenlet.kill()
                    return None
                if msg:  # message available
                    return self._decode_received(msg)