(Swift 3,4,5...) 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.

Chilkat Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

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

    let ssh = CkoSsh()!

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

    var cmdOutput: String?

    // Connect to an SSH server:
    var hostname: String?
    var port: Int

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

    var success: Bool = ssh.connect(hostname, port: port)
    if success != true {
        print("\(ssh.lastErrorText!)")
        return
    }

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

    // Authenticate using login/password:
    success = ssh.authenticatePw("myLogin", password: "myPassword")
    if success != true {
        print("\(ssh.lastErrorText!)")
        return
    }

    // Open a session channel.  (It is possible to have multiple
    // session channels open simultaneously.)
    var channelNum: Int
    channelNum = ssh.openSessionChannel().intValue
    if channelNum < 0 {
        print("\(ssh.lastErrorText!)")
        return
    }

    var termType: String? = "dumb"
    var widthInChars: Int = 120
    var heightInChars: Int = 40
    // Use 0 for pixWidth and pixHeight when the dimensions
    // are set in number-of-chars.
    var pixWidth: Int = 0
    var pixHeight: Int = 0
    success = ssh.sendReqPty(channelNum, xTermEnvVar: termType, widthInChars: widthInChars, heightInRows: heightInChars, pixWidth: pixWidth, pixHeight: pixHeight)
    if success != true {
        print("\(ssh.lastErrorText!)")
        return
    }

    // Start a shell on the channel:
    success = ssh.sendReqShell(channelNum)
    if success != true {
        print("\(ssh.lastErrorText!)")
        return
    }

    //  Run the 1st command in the remote shell, which will be to
    //  "cd" to a subdirectory.
    success = ssh.channelSendString(channelNum, strData: "cd workspace\r\n", charset: "ansi")
    if success != true {
        print("\(ssh.lastErrorText!)")
        return
    }

    // Retrieve the output.
    success = ssh.channelReceive(untilMatch: channelNum, matchPattern: myPrompt, charset: "ansi", caseSensitive: true)
    if success != true {
        print("\(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, charset: "ansi")
    if ssh.lastMethodSuccess != true {
        print("\(ssh.lastErrorText!)")
        return
    }

    print("\(cmdOutput!)")

    //  Run the 2nd command in the remote shell, which will be
    //  to "ls" the directory.
    success = ssh.channelSendString(channelNum, strData: "ls\r\n", charset: "ansi")
    if success != true {
        print("\(ssh.lastErrorText!)")
        return
    }

    // Retrieve and display the output.
    success = ssh.channelReceive(untilMatch: channelNum, matchPattern: myPrompt, charset: "ansi", caseSensitive: true)
    if success != true {
        print("\(ssh.lastErrorText!)")
        return
    }

    cmdOutput = ssh.getReceivedText(channelNum, charset: "ansi")
    if ssh.lastMethodSuccess != true {
        print("\(ssh.lastErrorText!)")
        return
    }

    print("\(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, strData: "ls -l\r\n", charset: "ansi")
    if success != true {
        print("\(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 {
        print("\(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: Int
    var pollTimeoutMs: Int = 2000
    n = ssh.channelReadAndPoll(channelNum, pollTimeoutMs: pollTimeoutMs).intValue
    if n < 0 {
        print("\(ssh.lastErrorText!)")
        return
    }

    // Close the channel:
    success = ssh.channelSendClose(channelNum)
    if success != true {
        print("\(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.channelReceive(toClose: channelNum)
    if success != true {
        print("\(ssh.lastErrorText!)")
        return
    }

    cmdOutput = ssh.getReceivedText(channelNum, charset: "ansi")
    if ssh.lastMethodSuccess != true {
        print("\(ssh.lastErrorText!)")
        return
    }

    print("\(cmdOutput!)")

    // Disconnect
    ssh.disconnect()

}