Node.js

Using sudo in an SSH Shell Session

See more SSH Examples

Demonstrates how to run a command as sudo in a shell session. Node.js

NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

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

    var ssh = new chilkat.Ssh();

    var port = 22;
    success = ssh.Connect("the-ssh-server.com",port);
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    //  Authenticate using login/password:
    success = ssh.AuthenticatePw("theSshLogin","theSshPassword");
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    //  Start a shell session.
    //  (The QuickShell method was added in Chilkat v9.5.0.65)
    var channelNum = ssh.QuickShell();
    if (channelNum < 0) {
        console.log(ssh.LastErrorText);
        return;
    }

    //  Construct a StringBuilder with our command ("ls") run with "sudo"
    //  Note: The line-endings are potentially important.  Some SSH servers may
    //  require either LF or CRLF line endings.  (Unix/Linux/OSX servers typically
    //  use bare-LF line endings.  Windows servers likely use CRLF line endings.)

    //  Using "sudo -S" causes the sudo prompt to be written to stderr,
    //  and the password is read from stdin (i.e. from the echo command ouput).
    //  The sudo commands -p option allows us to set the prompt, and we can set it to
    //  the empty string, thus eliminating the prompt from the stderr completely.
    //  This allows us to run the command as root (super-user) with no prompt.
    var sbCommands = new chilkat.StringBuilder();
    sbCommands.Append("echo \"theSshPassword\" | sudo -S -p \"\" ls\n");

    //  Add another command to echo a marker string that
    //  we'll use in ChannelReceiveUntilMatch below.
    //  The use of single quotes around 'IS' is a trick so that the output
    //  of the command is "THIS IS THE END OF THE SCRIPT", but the terminal echo
    //  includes the single quotes.  This allows us to read until we see the actual
    //  output of the last command.
    sbCommands.Append("echo THIS 'IS' THE END OF THE SCRIPT\n");

    //  Send the commands..
    success = ssh.ChannelSendString(channelNum,sbCommands.GetAsString(),"ansi");
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    //  Send an EOF to indicate no more commands will be sent.
    //  For brevity, we're not checking the return values of each method call.
    //  Your code should check the success/failure of each call.
    success = ssh.ChannelSendEof(channelNum);

    //  Receive output up to our marker.
    success = ssh.ChannelReceiveUntilMatch(channelNum,"THIS IS THE END OF THE SCRIPT","ansi",true);

    //  Close the channel.
    //  It is important to close the channel only after receiving the desired output.
    success = ssh.ChannelSendClose(channelNum);

    //  Get any remaining output..
    success = ssh.ChannelReceiveToClose(channelNum);

    //  Get the complete output for all the commands in the session.
    console.log("--- output ----");
    console.log(ssh.GetReceivedText(channelNum,"ansi"));

}

chilkatExample();