Delphi ActiveX

Close an IMAP SSH Tunnel

Demonstrates the Chilkat Imap.SshCloseTunnel method, which closes the SSH tunnel opened by SshOpenTunnel. It takes no arguments. Any IMAP connection that was using the tunnel must not be used after the tunnel is closed.

Background: The SSH tunnel is the transport that carries the IMAP session, so closing it tears down that transport. Disconnect or finish with the IMAP connection first, then close the tunnel to release the SSH resources cleanly. Continuing to use an IMAP connection whose tunnel has been closed will fail.

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var
success: Integer;
imap: TChilkatImap;
sshPort: Integer;
sshPassword: WideString;

begin
success := 0;

//  Demonstrates the Imap.SshCloseTunnel method, which closes the SSH tunnel opened by
//  SshOpenTunnel.  It takes no arguments.  Any IMAP connection using the tunnel must not be
//  used after the tunnel is closed.

imap := TChilkatImap.Create(Self);

sshPort := 22;
success := imap.SshOpenTunnel('ssh.example.com',sshPort);
if (success = 0) then
  begin
    Memo1.Lines.Add(imap.LastErrorText);
    Exit;
  end;

//  The SSH password is not hard-coded in source.  Insert code here to obtain it from an
//  interactive prompt, environment variable, or a secrets vault.

success := imap.SshAuthenticatePw('sshUser',sshPassword);
if (success = 0) then
  begin
    Memo1.Lines.Add(imap.LastErrorText);
    Exit;
  end;

//  With the SSH tunnel in place, connect and log in to the IMAP server as usual.  The IMAP
//  traffic flows through the tunnel automatically.
imap.Ssl := 1;
imap.Port := 993;
success := imap.Connect('imap.example.com');
if (success = 0) then
  begin
    Memo1.Lines.Add(imap.LastErrorText);
    Exit;
  end;
success := imap.Login('user@example.com','myPassword');
if (success = 0) then
  begin
    Memo1.Lines.Add(imap.LastErrorText);
    Exit;
  end;

//  ... use the IMAP connection ...

success := imap.Disconnect();
if (success = 0) then
  begin
    Memo1.Lines.Add(imap.LastErrorText);
    Exit;
  end;

//  Close the SSH tunnel.  Do not use the IMAP connection after this point.
success := imap.SshCloseTunnel();
if (success = 0) then
  begin
    Memo1.Lines.Add(imap.LastErrorText);
    Exit;
  end;