FluentFTP.Monitors AsyncFtpMonitor issue

[h4z0rQ]

Hello, is there an issue with StartTimer(PollInterval) in AsyncFtpMonitor? It seems like PollInterval is not working correctly — the server is being polled continuously without any delay.

I changed the StartTimer implementation from:

internal void StartTimer(TimerCallback callback)
{
    _timer = new Timer(callback, null, TimeSpan.Zero, PollInterval);
}

To this:

internal void StartTimer(TimerCallback callback)
{
    _timer = new Timer(callback, null, TimeSpan.FromSeconds(1), PollInterval);
}

After this change, the timer behaves as expected and polls the server every second. PollInterval value is completly ignored.

[FanDjango]

The last two parameters are "dueTime" and "period".

A dueTime of TimeSpan.Zero means: First execution of callback is done immediately.

A period of PollInterval means: From the first execution onwards, repeat execution of callback every PollInterval.

So I believe the original code to be correct. You might want to check your PollInterval setting.

[FanDjango]

Perhaps some proof of your problem, logs etc. would help?

[h4z0rQ]

The logic seems to be broken when declaring the Timer in StartTimer, where polling starts immediately with TimeSpan.Zero. Then, in the PollFolder callback, StopTimer is called, which disposes the Timer. At the end of the function, StartTimer is invoked again, creating a loop delayed by dueTime.

Behaviours:

  private async void TestMonitor()
  {
      
      FluentFTP.AsyncFtpClient monasyncFtp = new FluentFTP.AsyncFtpClient("127.0.0.1", networkCredential, 21);
      var testMonitor = new FluentFTP.Monitors.AsyncFtpMonitor(monasyncFtp, new List<string>() { "/" });
     
      //Ignored PollInterval
      testMonitor.PollInterval = TimeSpan.FromHours(10);
      await testMonitor.Start();
}

Polling log:

Behaviours while override StartMonitor:

 public class MyAsyncMonitor : BaseFtpMonitor
 {  
        
       public TimeSpan DueTime;
        public MyAsyncMonitor(AsyncFtpClient ftpClient, List<string> folderPaths, TimeSpan dueTime)
        {
            _ftpClient = ftpClient;
            FolderPaths = folderPaths;
            DueTime = dueTime;
        }

        public new void StartTimer(TimerCallback callback)
        {
            _timer = new System.Threading.Timer(callback, null, DueTime, PollInterval);
        }
}

var testMonitor = new MyAsyncMonitor(monasyncFtp, new List<string>() { "/" }, TimeSpan.FromSeconds(10));

Polling log:

[FanDjango]

Ah, I see.

creating a loop delayed by dueTime.

Funny to code it that way. Needs looking into.