Method periodic_ping

tornado/websocket.py:1354–1385

Send a ping and wait for a pong if ping_timeout is configured. Called periodically if the websocket_ping_interval is set and non-zero.

(self)

        return max(0, last_ping_time + interval - now)

    async def periodic_ping(self) -> None:
        """Send a ping and wait for a pong if ping_timeout is configured.

        Called periodically if the websocket_ping_interval is set and non-zero.
        """
        interval = self.ping_interval
        timeout = self.ping_timeout

        await asyncio.sleep(interval)

        while True:
            # send a ping
            self._received_pong = False
            ping_time = IOLoop.current().time()
            self.write_ping(b"")

            # wait until the ping timeout
            await asyncio.sleep(timeout)

            # make sure we received a pong within the timeout
            if timeout > 0 and not self._received_pong:
                self.close(reason="ping timed out")
                return

            # wait until the next scheduled ping
            await asyncio.sleep(
                self.ping_sleep_time(
                    last_ping_time=ping_time,
                    interval=interval,
                    now=IOLoop.current().time(),
                )
            )


class WebSocketClientConnection(simple_httpclient._HTTPConnection):