(Go) SSH Tunnel with Dynamic Port Forwarding

Demonstrates how to start a background thread that runs a portable SSH tunnel w/ dynamic port forwarding that the foreground thread can use for establishing connections through an SSH tunnel.

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    // Starting in v9.5.0.49, all Chilkat classes can be unlocked at once at the beginning of a program
    // by calling UnlockBundle.  It requires a Bundle unlock code.
    chilkatGlob := chilkat.NewGlobal()
    success := chilkatGlob.UnlockBundle("Anything for 30-day trial.")
    if success != true {
        fmt.Println(chilkatGlob.LastErrorText())
        chilkatGlob.DisposeGlobal()
        return
    }

    // This example requires Chilkat version 9.5.0.50 or greater.
    tunnel := chilkat.NewSshTunnel()

    sshHostname := "sftp.example.com"
    sshPort := 22

    // Connect to an SSH server and establish the SSH tunnel:
    success = tunnel.Connect(sshHostname,sshPort)
    if success != true {
        fmt.Println(tunnel.LastErrorText())
        chilkatGlob.DisposeGlobal()
        tunnel.DisposeSshTunnel()
        return
    }

    // Authenticate with the SSH server via a login/password
    // or with a public key.  
    // This example demonstrates SSH password authentication.
    success = tunnel.AuthenticatePw("mySshLogin","mySshPassword")
    if success != true {
        fmt.Println(tunnel.LastErrorText())
        chilkatGlob.DisposeGlobal()
        tunnel.DisposeSshTunnel()
        return
    }

    // Indicate that the background SSH tunnel thread will behave as a SOCKS proxy server
    // with dynamic port forwarding:
    tunnel.SetDynamicPortForwarding(true)

    // We may optionally require that connecting clients authenticate with our SOCKS proxy server.
    // To do this, set an inbound username/password.  Any connecting clients would be required to 
    // use SOCKS5 with the correct username/password.
    // If no inbound username/password is set, then our SOCKS proxy server will accept both
    // SOCKS4 and SOCKS5 unauthenticated connections.

    tunnel.SetInboundSocksUsername("chilkat123")
    tunnel.SetInboundSocksPassword("password123")

    // Start the listen/accept thread to begin accepting SOCKS proxy client connections.
    // Listen on port 1080.
    success = tunnel.BeginAccepting(1080)
    if success != true {
        fmt.Println(tunnel.LastErrorText())
        chilkatGlob.DisposeGlobal()
        tunnel.DisposeSshTunnel()
        return
    }

    // Now that a background thread is running a SOCKS proxy server that forwards connections
    // through an SSH tunnel, it is possible to use any Chilkat implemented protocol that is SOCKS capable,
    // such as HTTP, POP3, SMTP, IMAP, FTP, etc.  The protocol may use SSL/TLS because the SSL/TLS
    // will be passed through the SSH tunnel to the end-destination.  Also, any number of simultaneous
    // connections may be routed through the SSH tunnel.

    // For this example, let's do a simple HTTPS request:
    url := "https://www.ethereum.org/"

    http := chilkat.NewHttp()

    // Indicate that the HTTP object is to use our portable SOCKS proxy/SSH tunnel running in our background thread.
    http.SetSocksHostname("localhost")
    http.SetSocksPort(1080)
    http.SetSocksVersion(5)
    http.SetSocksUsername("chilkat123")
    http.SetSocksPassword("password123")

    http.SetSendCookies(true)
    http.SetSaveCookies(true)
    http.SetCookieDir("memory")

    // Do the HTTPS page fetch (through the SSH tunnel)
    html := http.QuickGetStr(url)
    if http.LastMethodSuccess() != true {
        fmt.Println(http.LastErrorText())
        chilkatGlob.DisposeGlobal()
        tunnel.DisposeSshTunnel()
        http.DisposeHttp()
        return
    }

    // Stop the background listen/accept thread:
    waitForThreadExit := true
    success = tunnel.StopAccepting(waitForThreadExit)
    if success != true {
        fmt.Println(tunnel.LastErrorText())
        chilkatGlob.DisposeGlobal()
        tunnel.DisposeSshTunnel()
        http.DisposeHttp()
        return
    }

    // Close the SSH tunnel (would also kick any remaining connected clients).
    success = tunnel.CloseTunnel(waitForThreadExit)
    if success != true {
        fmt.Println(tunnel.LastErrorText())
        chilkatGlob.DisposeGlobal()
        tunnel.DisposeSshTunnel()
        http.DisposeHttp()
        return
    }


    chilkatGlob.DisposeGlobal()
    tunnel.DisposeSshTunnel()
    http.DisposeHttp()