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JavaScript Requires Chilkat v11.0.0+

POP3 SSH Tunneling (Port Forwarding)

Demonstrates how to connect to a POP3 server through an SSH tunnel. Reads a POP3 mailbox and display the FROM and SUBJECT header fields of each email.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
var success = false;

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

//  The mailman object is used for receiving (POP3) 
//  and sending (SMTP) email.
var mailman = new CkMailMan();

//  The SSH hostname may be a hostname or an 
//  IP address, such as "192.168.1.108".
//  The port is typically 22 (the standard port for SSH).
var sshHostname = "sftp.example.com";
var sshPort = 22;

//  Connect to an SSH server and establish the SSH tunnel:
success = mailman.SshOpenTunnel(sshHostname,sshPort);
if (success == false) {
    console.log(mailman.LastErrorText);
    return;
}

//  Authenticate with the SSH server via a login/password
//  or with a public key.
//  This example demonstrates SSH password authentication.
//  Note: This is not authenticating with the POP3 server, it is
//  for authenticating with the SSH server, which is separate.
success = mailman.SshAuthenticatePw("ssh_login","ssh_password");
if (success == false) {
    console.log(mailman.LastErrorText);
    return;
}

//  OK, the SSH tunnel is setup.  The mailman may
//  be used exactly the same as usual, except all communications
//  are now sent through the SSH tunnel.

//  The SSH tunnel may be kept open for any number of 
//  POP3 connections.  

//  Set the POP3 server's hostname
mailman.MailHost = "mail.my-pop3-server.com";

//  Set the POP3 settings for your POP3 server:
mailman.PopUsername = "pop3_login";
mailman.PopPassword = "pop3_password";
mailman.MailPort = 995;
mailman.PopSsl = true;

//  Connect to the POP3 server through the already-established SSH tunnel:
success = mailman.Pop3BeginSession();
if (success == false) {
    console.log(mailman.LastErrorText);
    return;
}

//  A visual inspection of the LastErrorText after
//  a successful POP3 connection will confirm the SSH tunneling.
//  Note: If the POP3 connection uses SSL/TLS, then the SSL/TLS 
//  secure channel will be wrapped within the SSH tunnel.
console.log(mailman.LastErrorText);

//  How many messages are in the POP3 inbox?
var numToDownload = mailman.GetMailboxCount();
if (numToDownload > 5) {
    numToDownload = 5;
}

if (numToDownload == 0) {
    console.log("No messages in the POP3 inbox.");
    return;
}

//  Download a max of 5 messages
var i;
var email = new CkEmail();
for (i = 1; i <= numToDownload; i++) {
    success = mailman.FetchOne(false,0,i,email);
    if (success == false) {
        console.log(mailman.LastErrorText);
        return;
    }

    console.log(email.From);
    console.log(email.Subject);
    console.log("----");
}

//  Close the connection with the POP3 server, leaving the SSH tunnel open for subsequent POP3 connections.
success = mailman.Pop3EndSession();
if (success == false) {
    console.log(mailman.LastErrorText);
    return;
}

//  Try connecting to a different POP3 server through the same aleady setup SSH tunnel:
//  Set the POP3 server's hostname
mailman.MailHost = "mail.my-pop3-server2.com";

//  Set the POP3 settings for your POP3 server:
mailman.PopUsername = "pop3_login2";
mailman.PopPassword = "pop3_password2";
mailman.MailPort = 110;
mailman.PopSsl = false;

success = mailman.Pop3BeginSession();
if (success == false) {
    console.log(mailman.LastErrorText);
    return;
}

//  Review the LastErrorText to see that the connection was made via the SSH tunnel:
console.log(mailman.LastErrorText);

success = mailman.Pop3EndSession();
if (success == false) {
    console.log(mailman.LastErrorText);
    return;
}

//  Close the SSH tunnel.
success = mailman.SshCloseTunnel();
if (success == false) {
    console.log(mailman.LastErrorText);
    return;
}