(Go) IMAP SSH Tunneling (Port Forwarding)

Demonstrates how to setup and use an SSH tunnel for IMAP.

Note: This example requires Chilkat v11.0.0 or greater.

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    success := false

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

    imap := Imap_Ref.html">chilkat.NewImap()

    // 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).
    sshHostname := "www.mysshserver.com"
    sshPort := 22

    // Connect to an SSH server and establish the SSH tunnel:
    success = imap.SshOpenTunnel(sshHostname,sshPort)
    if success == false {
        fmt.Println(imap.LastErrorText())
        imap.DisposeImap()
        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 IMAP server, it is
    // for authenticating with the SSH server, which is separate.
    success = imap.SshAuthenticatePw("mySshLogin","mySshPassword")
    if success == false {
        fmt.Println(imap.LastErrorText())
        imap.DisposeImap()
        return
    }

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

    // Connect to an IMAP server via the SSH tunnel.
    // Because the SSH tunnel has been previously setup,
    // this does not establish a direct connection with the IMAP
    // server.  It directs the SSH server to establish the connection.

    // In this example, the IMAP server requires SSL/TLS.  The TLS connection
    // will be enclosed within the SSH tunnel.
    imap.SetSsl(true)
    imap.SetPort(993)
    success = imap.Connect("imap.my-imap-server.com")
    if success == false {
        fmt.Println(imap.LastErrorText())
        imap.DisposeImap()
        return
    }

    // Authenticate with the IMAP server via the SSH tunnel.
    success = imap.Login("myLogin","myPassword")
    if success == false {
        fmt.Println(imap.LastErrorText())
        imap.DisposeImap()
        return
    }

    // Select an IMAP mailbox
    success = imap.SelectMailbox("Inbox")
    if success == false {
        fmt.Println(imap.LastErrorText())
        imap.DisposeImap()
        return
    }

    // How many messages in Inbox?
    msgCount := imap.NumMessages()
    if msgCount == 0 {
        fmt.Println("No messages found.")
        imap.DisposeImap()
        return
    }

    upperBound := 10
    if msgCount < upperBound {
        upperBound = msgCount
    }

    // Download up to the 1st 10 messages.
    email := Email_Ref.html">chilkat.NewEmail()
    var i int
    bUid := false
    for i = 1; i <= upperBound; i++ {

        success = imap.FetchEmail(false,i,bUid,email)
        if success == false {
            fmt.Println(imap.LastErrorText())
            imap.DisposeImap()
            email.DisposeEmail()
            return
        }

        fmt.Println(email.From())
        fmt.Println(email.Subject())
        fmt.Println("----")
    }

    // Disconnect from the IMAP server.
    // The SSH tunnel remains open.
    success = imap.Disconnect()
    if success == false {
        fmt.Println(imap.LastErrorText())
        imap.DisposeImap()
        email.DisposeEmail()
        return
    }

    // It is possible to re-use the existing SSH tunnel for the next connection:
    success = imap.Connect("imap.my-imap-server2.com")
    if success == false {
        fmt.Println(imap.LastErrorText())
        imap.DisposeImap()
        email.DisposeEmail()
        return
    }

    // Review the LastErrorText to see that the connection was made via the SSH tunnel:
    fmt.Println(imap.LastErrorText())

    success = imap.Disconnect()
    if success == false {
        fmt.Println(imap.LastErrorText())
        imap.DisposeImap()
        email.DisposeEmail()
        return
    }

    // Finally, close the SSH tunnel.
    success = imap.SshCloseTunnel()
    if success == false {
        fmt.Println(imap.LastErrorText())
        imap.DisposeImap()
        email.DisposeEmail()
        return
    }

    fmt.Println("IMAP SSH tunneling example completed.")

    imap.DisposeImap()
    email.DisposeEmail()