Automation and more: February 2020

Automation brings many challenges which need different solutions. We also came to a situation where we had to execute a command on a Linux platform, or, read a file/log from the Linux platform.

We created a groovy script to achieve the same. We had a lot of help from several blogs and sites and I thought it would be interesting to put the result as a complete solution at once place.

import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PipedInputStream;
import java.io.PipedOutputStream;
import java.io.PrintStream;
import java.io.Reader;
import java.util.Properties;

import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelExec;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;

class serviceManagement {

JSch jsch = new JSch();
        Session session = jsch.getSession(usrPrim, host, 22);
        session.setConfig("StrictHostKeyChecking", "no");
        session.setPassword(pwdPrim);
        session.connect();

// Define variable to read into
        def fileContent=""

Channel channel = session.openChannel("sftp");
        channel.connect();
        ChannelSftp sftpChannel = (ChannelSftp) channel;
        InputStream stream = sftpChannel.get(Cmd);
        try{
            BufferedReader br = new BufferedReader(new InputStreamReader(stream));
            String line;
            while ((line = br.readLine()) != null) {
                fileContent = line + fileContent
            }
        }
        catch (Exception e) {
            log.error ("Exception occurred during reading file from SFTP server due to " + e.getMessage());
        }
        return fileContent
    }

// Define variable to be used in the function
    /*
     * ----------------------------------------------------------------------------------------------------------------------------------------------
     * Funtion executeCmd definition
     * Description : executes a given command on the linux platform
     * Parameters :
     *    host : IP
     *    Cmd : File to read
     *    usrPrim : Primary user account to connect
     *    pwdPrim : Primary user account password
     *          executedBySecondary : "true/false" based on whether the command to be launched as secondary user(root) or not
     *          usrSecond : secondary user account to connect
     *          pwdSecond : secondary user account password
     */
    public void executeCmd(String host, String Cmd, String usrPrim, String pwdPrim, boolean executedBySecondary, String usrSecond, String pwdSecond)
    {
        JSch jsch = new JSch();

// verify if the command has to be executed by secondary user or by the primary login
        Session session = jsch.getSession(usrPrim, host, 22);
        session.setConfig("StrictHostKeyChecking", "no");

session.setPassword(pwdPrim);
        session.connect();

Channel channel = session.openChannel("shell");
        OutputStream chlInputStream = channel.getOutputStream();
        InputStream chlOutStream = channel.getInputStream();
        InputStream chlErrStream = channel.getExtInputStream();
        BufferedReader br = new BufferedReader(new InputStreamReader(chlOutStream));
        String line;
        PrintStream cmderShell = new PrintStream(chlInputStream, true);

channel.connect();

byte[] tmp = new byte[1024];
        String stdOut = "";
        String stdErr = "";
        int i;

if (executedBySecondary)
        {
            log.info " Log in as " + usrSecond + " with password : " + pwdSecond
            cmderShell.println("su - " + usrSecond + "\n");
            while(true){
                if(chlErrStream.available() > 0){
                    i = chlErrStream.read(tmp, 0, tmp.length);
                    if (i < 0)
                        exit(1)
                    stdErr += new String(tmp, 0, i);
                    log.info (" Read from Standard Error stream : " + stdErr);
                }
                if(chlOutStream.available() > 0){
                    i = chlOutStream.read(tmp, 0, tmp.length);
                    if (i < 0)
                        exit(1)
                    stdOut += new String(tmp, 0, i);
                    log.info (" Read from Standard Output stream : " + stdOut);
                }
                if (stdOut.contains("assword"))
                    break;
                Thread.sleep(1000);
            }
            cmderShell.println(pwdSecond + "\n");
            cmderShell.println("id");
            cmderShell.println(Cmd);
            cmderShell.println("exit");
        }
        else
            cmderShell.println(Cmd);

cmderShell.println("exit");
        cmderShell.close();

while((line = br.readLine()) != null)
            log.info line
        channel.disconnect();
        session.disconnect();
    }
}

Automation and more

Sunday 9 February 2020

SoapUI: Performing Actions on Linux Machine

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