Dart

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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Dart

import 'package:chilkat/chilkat.dart';

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

  final tunnel = CkSshTunnel();

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

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

  tunnel.destHostname = 'db.internal.example.com';
  tunnel.destPort = 5432;

  final sshPort = 22;
  try {
    tunnel.connect('ssh.example.com', sshPort);
  } on ChilkatException catch (e) {
    print(e.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.
  final password = 'mySshPassword';

  try {
    tunnel.authenticatePw('mySshLogin', password);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final listenPort = 1080;
  try {
    tunnel.beginAccepting(listenPort);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

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

  // Read the accumulated in-memory listener log.
  print(tunnel.acceptLog);

  final waitForThreadExit = true;
  try {
    tunnel.closeTunnel(waitForThreadExit);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }
}