How to make FluentFTP to log to log4net log?

Question

I couldn't find any information on how to do it. Basically FluentFTP is using System.Diagnostics to log their messages. FluentFtp expose the following static method:

FtpTrace.AddListener(TraceListener listener);

However I don't know if there is any way to implement (or use existing implementation, which?) TraceListener in the way it relays everything to log4net engine.

Any hints or ideas?

Thanks, Radek

Answer 1

You can attach a listener to the OnLogEvent method that FluentFTP exposes.

private static readonly log4net.ILog Log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

public static void UploadFTP(FileInfo localFile, string remoteFileLocation, string remoteServer, NetworkCredential credentials)
{
    FtpClient client = new FtpClient(remoteServer, credentials);
    client.RetryAttempts = 3;
    client.OnLogEvent = OnFTPLogEvent;

    client.Connect();

    if (!client.UploadFile(localFile.FullName, remoteFileLocation, FtpExists.Overwrite, false, FtpVerify.Retry | FtpVerify.Throw))
    {
        throw new Exception($"Could not Upload File {localFile.Name}. See Logs for more information");
    }
}

private static void OnFTPLogEvent(FtpTraceLevel ftpTraceLevel, string logMessage)
{
    switch (ftpTraceLevel)
    {
        case FtpTraceLevel.Error:
            Log.Error(logMessage);
            break;
        case FtpTraceLevel.Verbose:
            Log.Debug(logMessage);
            break;
        case FtpTraceLevel.Warn:
            Log.Warn(logMessage);
            break;
        case FtpTraceLevel.Info:
        default:
            Log.Info(logMessage);
            break;
    }
}

The method OnFTPLogEvent will be called every-time the OnLogEvent action will be called allowing you to extend any logging you have already built into your application.