(Node.js) SSH Remote Shell

Demonstrates how to start a shell on a remote SSH server, run a command, and retrieve the output.

Install Chilkat for Node.js and Electron using npm at Chilkat npm packages for Node.js Chilkat npm packages for Electron on Windows, Linux, MacOSX, and ARM

var os = require('os');
if (os.platform() == 'win32') {  
    if (os.arch() == 'ia32') {
        var chilkat = require('@chilkat/ck-node21-win-ia32');
    } else {
        var chilkat = require('@chilkat/ck-node21-win64'); 
    }
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node21-arm');
    } else if (os.arch() == 'x86') {
        var chilkat = require('@chilkat/ck-node21-linux32');
    } else {
        var chilkat = require('@chilkat/ck-node21-linux64');
    }
} else if (os.platform() == 'darwin') {
    if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node21-mac-m1');
    } else {
        var chilkat = require('@chilkat/ck-node21-macosx');
    }
}

function chilkatExample() {

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

    var ssh = new chilkat.Ssh();

    // Hostname may be an IP address or hostname:
    var hostname = "www.some-ssh-server.com";
    var port = 22;

    // Connect to an SSH server:
    var success = ssh.Connect(hostname,port);
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Wait a max of 5 seconds when reading responses..
    ssh.IdleTimeoutMs = 5000;

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

    // Open a session channel.  (It is possible to have multiple
    // session channels open simultaneously.)
    var channelNum;
    channelNum = ssh.OpenSessionChannel();
    if (channelNum < 0) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Some SSH servers require a pseudo-terminal
    // If so, include the call to SendReqPty.  If not, then 
    // comment out the call to SendReqPty.
    // Note: The 2nd argument of SendReqPty is the terminal type,
    // which should be something like "xterm", "vt100", "dumb", etc.
    // A "dumb" terminal is one that cannot process escape sequences.
    // Smart terminals, such as "xterm", "vt100", etc. process
    // escape sequences.  If you select a type of smart terminal,
    // your application will receive these escape sequences
    // included in the command's output.  Use "dumb" if you do not
    // want to receive escape sequences.  (Assuming your SSH
    // server recognizes "dumb" as a standard dumb terminal.)
    var termType = "dumb";
    var widthInChars = 120;
    var heightInChars = 40;
    // Use 0 for pixWidth and pixHeight when the dimensions
    // are set in number-of-chars.
    var pixWidth = 0;
    var pixHeight = 0;
    success = ssh.SendReqPty(channelNum,termType,widthInChars,heightInChars,pixWidth,pixHeight);
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Start a shell on the channel:
    success = ssh.SendReqShell(channelNum);
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Start a command in the remote shell.  This example
    // will send a "ls" command to retrieve the directory listing.
    success = ssh.ChannelSendString(channelNum,"ls\r\n","ansi");
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Send an EOF.  This tells the server that no more data will 
    // be sent on this channel.  The channel remains open, and
    // the SSH client may still receive output on this channel.
    success = ssh.ChannelSendEof(channelNum);
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Read whatever output may already be available on the
    // SSH connection.  ChannelReadAndPoll returns the number of bytes
    // that are available in the channel's internal buffer that
    // are ready to be "picked up" by calling GetReceivedText
    // or GetReceivedData.
    // A return value of -1 indicates failure.
    // A return value of -2 indicates a failure via timeout.

    // The ChannelReadAndPoll method waits
    // for data to arrive on the connection usingi the IdleTimeoutMs
    // property setting.  Once the first data arrives, it continues
    // reading but instead uses the pollTimeoutMs passed in the 2nd argument:
    // A return value of -2 indicates a timeout where no data is received.
    var n;
    var pollTimeoutMs = 2000;
    n = ssh.ChannelReadAndPoll(channelNum,pollTimeoutMs);
    if (n < 0) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Close the channel:
    success = ssh.ChannelSendClose(channelNum);
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Perhaps we did not receive all of the commands output.
    // To make sure,  call ChannelReceiveToClose to accumulate any remaining
    // output until the server's corresponding "channel close" is received.
    success = ssh.ChannelReceiveToClose(channelNum);
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Let's pickup the accumulated output of the command:
    var cmdOutput = ssh.GetReceivedText(channelNum,"ansi");
    if (ssh.LastMethodSuccess !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Display the remote shell's command output:
    console.log(cmdOutput);

    // Disconnect
    ssh.Disconnect();

}

chilkatExample();