(Node.js) SSH Remote Shell Multiple Commands

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

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();

    // This is the prompt we'll be expecting to find in
    // the output of the remote shell.
    var myPrompt;
    myPrompt = "chilkat@ubuntu:~/workspace$";

    var cmdOutput;

    // Connect to an SSH server:
    var hostname;
    var port;

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

    var success = ssh.Connect(hostname,port);
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Wait a max of 10 seconds when reading responses..
    ssh.IdleTimeoutMs = 10000;

    // 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;
    }

    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;
    }

    //  Run the 1st command in the remote shell, which will be to
    //  "cd" to a subdirectory.
    success = ssh.ChannelSendString(channelNum,"cd workspace\r\n","ansi");
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Retrieve the output.
    success = ssh.ChannelReceiveUntilMatch(channelNum,myPrompt,"ansi",true);
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    //  Display what we've received so far.  This clears
    //  the internal receive buffer, which is important.
    //  After we send the command, we'll be reading until
    //  the next command prompt.  If the command prompt
    //  is already in the internal receive buffer, it'll think it's
    //  already finished...
    cmdOutput = ssh.GetReceivedText(channelNum,"ansi");
    if (ssh.LastMethodSuccess !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    console.log(cmdOutput);

    //  Run the 2nd command in the remote shell, which will be
    //  to "ls" the directory.
    success = ssh.ChannelSendString(channelNum,"ls\r\n","ansi");
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    // Retrieve and display the output.
    success = ssh.ChannelReceiveUntilMatch(channelNum,myPrompt,"ansi",true);
    if (success !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    cmdOutput = ssh.GetReceivedText(channelNum,"ansi");
    if (ssh.LastMethodSuccess !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    console.log(cmdOutput);

    //  Start the final command in the remote shell.  This example
    //  will send a "ls -l" command to retrieve the long format directory listing.
    success = ssh.ChannelSendString(channelNum,"ls -l\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;
    }

    cmdOutput = ssh.GetReceivedText(channelNum,"ansi");
    if (ssh.LastMethodSuccess !== true) {
        console.log(ssh.LastErrorText);
        return;
    }

    console.log(cmdOutput);

    // Disconnect
    ssh.Disconnect();

}

chilkatExample();