Java

SSH Tunnel Listener Activity Log

Demonstrates the listener-log properties KeepAcceptLog, AcceptLog, and AcceptLogPath, which record the activity of the background listener thread started by BeginAccepting.

Note: The log paths are relative to the application's current working directory. Absolute paths may also be used.

Background: Because the listener runs on a background thread, an activity log is often the only practical way to see what it is doing — which connections it accepted and when. KeepAcceptLog must be enabled for the in-memory AcceptLog to be populated; AcceptLogPath is an independent file-based log that persists across the run. This log covers the listener specifically, as distinct from the TunnelLog that records the SSH tunnel threads.

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Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    //  Demonstrates the SshTunnel listener-log properties KeepAcceptLog, AcceptLog, and AcceptLogPath.
    //  
    //  These log the activity of the background listener thread started by BeginAccepting.

    CkSshTunnel tunnel = new CkSshTunnel();

    //  Retain the listener activity log in memory so it can be read from the AcceptLog property.
    tunnel.put_KeepAcceptLog(true);

    //  Optionally also write the listener activity to a file (separate from the in-memory log).
    tunnel.put_AcceptLogPath("qa_output/accept.log");

    tunnel.put_DestHostname("db.internal.example.com");
    tunnel.put_DestPort(5432);

    int sshPort = 22;
    success = tunnel.Connect("ssh.example.com",sshPort);
    if (success == false) {
        System.out.println(tunnel.lastErrorText());
        return;
        }

    //  Normally you would not hard-code the password in source.  You should instead obtain it
    //  from an interactive prompt, environment variable, or a secrets vault.
    String password = "mySshPassword";

    success = tunnel.AuthenticatePw("mySshLogin",password);
    if (success == false) {
        System.out.println(tunnel.lastErrorText());
        return;
        }

    int listenPort = 1080;
    success = tunnel.BeginAccepting(listenPort);
    if (success == false) {
        System.out.println(tunnel.lastErrorText());
        return;
        }

    //  ... the listener accepts connections for a while ...

    //  Read the accumulated in-memory listener log.
    System.out.println(tunnel.acceptLog());

    boolean waitForThreadExit = true;
    success = tunnel.CloseTunnel(waitForThreadExit);
    if (success == false) {
        System.out.println(tunnel.lastErrorText());
        return;
        }
  }
}