private static async void PingServerAsync()

in iothub/device/src/Transport/Mqtt/MqttIotHubAdapter.cs [463:516]
41 lines of code
12 McCabe index (conditional complexity)

        private static async void PingServerAsync(object ctx)
        {
            if (Logging.IsEnabled)
                Logging.Enter(ctx, $"Scheduled check to see if a ping request should be sent.", nameof(PingServerAsync));

            var context = (IChannelHandlerContext)ctx;
            try
            {
                var self = (MqttIotHubAdapter)context.Handler;

                if (!self.IsInState(StateFlags.Connected))
                {
                    return;
                }

                TimeSpan idleTime = DateTime.UtcNow - self._lastChannelActivityTime;
                if (Logging.IsEnabled)
                    Logging.Info(context, $"Idle time currently is {idleTime}.", nameof(PingServerAsync));

                if (idleTime > self._pingRequestInterval)
                {
                    // We've been idle for too long, send a ping!
                    await WriteMessageAsync(context, PingReqPacket.Instance, s_shutdownOnWriteErrorHandler).ConfigureAwait(true);

                    if (Logging.IsEnabled)
                        Logging.Info(context, $"Idle time was {idleTime}, so ping request was sent.", nameof(PingServerAsync));

                    // Wait to capture the ping response semaphore, which is released when a PINGRESP packet is received.
                    bool receivedPingResponse = await s_pingResponseSemaphore.WaitAsync(s_pingResponseTimeout).ConfigureAwait(true);
                    if (!receivedPingResponse)
                    {
                        if (Logging.IsEnabled)
                            Logging.Info(context, $"The ping response wasn't received in {s_pingResponseTimeout}, will shut down.", nameof(PingServerAsync));

                        ShutdownOnErrorAsync(context, new TimeoutException($"The ping response wasn't received in {s_pingResponseTimeout}"));
                    }

                    if (Logging.IsEnabled)
                        Logging.Info(context, $"Ping response was received successfully.", nameof(PingServerAsync));
                }

                self.ScheduleKeepConnectionAliveAsync(context);
            }
            catch (Exception ex) when (!ex.IsFatal())
            {
                if (Logging.IsEnabled)
                    Logging.Error(context, $"A non-fatal exception occurred while sending a ping request, will shut down: {ex}", nameof(ConnectAsync));

                ShutdownOnErrorAsync(context, ex);
            }

            if (Logging.IsEnabled)
                Logging.Exit(ctx, $"Scheduled check to see if a ping request should be sent.", nameof(PingServerAsync));
        }