How To Use VNCRobot

• Example #1: Automated Tasks
• Example #2: Automated Functional And Regression Testing
• Example #3: Localization Testing
• Example #4: Availability Monitoring
• Example #5: Load Testing
  

Example #1: Automated Tasks

Example #2: Automated Functional And Regression Testing

1. Limitations - Testing must be designed with regards to the technology limitations,
2. Verification - Testing is more complex and there must be ways to verify the behavior and test results automatically,
3. Reporting - The test results and eventual failures need to be reported in an appropriate way.

• The VNC client (i.e. VNCRobot) knows just the image of the remote desktop. It is NOT implicitly aware of which OS it displays or which applications or windows are there. See the Verification chapter on how to analyze the remote desktop content and verify the desktop and application behavior.
• Remote desktops behave differently depending on OS version, installed software and user preferences. It means that if you develop a test script on one VNC server, it may or may not work on another one. To ensure stable and reliable behavior of VNCRobot automated testing always use one VNC server to execute your test suite (or eventually more VNC servers with identical desktop configuration).
• The RFB protocol is not able to transfer other than ISO8859-1 (Latin-1) characters. It means that you will not be able to simulate e.g. a user typing Chinese or Russian characters.
  
• It is not possible to execute two or more test suites on one VNC server instance at a time. On Linux/Unix it's not a problem because you can start as many server instances as you want and you can use a single machine for parallel execution of many automated tasks. Windows are more affected by this limitation because they can typically run just one VNC server instance. To use a Windows machine for parallel testing you may consider to take advantage of Windows Terminal Services and connect VNCRobot through an RDP to VNC Protocol Adaptor like rdp2vnc.

1. Monitoring of remote desktop image updates. Commands like Waifor update allow you to verify update of the remote desktop image, e.g. when an application window gets opened.
2. Monitoring of server beeps (bell characters). You may design CLI commands executed on the remote desktop to beep (i.e. print the bell character) in case of successful execution and take advantage of the Waifor bell command to capture it.
3. Image comparison methods. VNCRobot 1.3 supports two methods called "default" and "search". The first one is based on histogram comparison and allows to generate a percentage indicating how much the remote desktop image matches to a template image. The second one allows to search the remote desktop image or its part for a smaller image, e.g. an icon. Both methods are well described in the How to Use Image Comparison document of the VNCRobot GUI documentation. Users may also allowed to take advantage of the VNCRobot 1.3 Open API to write their own image comparison methods and plug them into VNCRobot.
   

• Sample test report which shows how to use VNCRobot reporting and verification tools on a simple automated test case,

• VNCRobot 1.2 Demo and the corresponding test report which will guide you through the process of automation using VNCRobot GUI.

Example #3: Localization Testing

• Design your test scripts to accept variable values from the command line. See -v/--variable switch in the VNCRobot CLI Options document for more information.
• When you create the automated test script, avoid using mouse clicks, moves and drags to control the tested application. Translations bring differencies into GUI component sizes and behavior and mouse controls are then not reliable. Stick to the keyboard where possible and control your application through simple keys, shotcut/hot keys, mnemonic keys and focus controls like Tab/Shift+Tab.
• Make sure your scripts leave the remote desktop in the same state as before execution. A good idea is to start always on a clean desktop which is not running any visible application. Calling of Ctrl+F4 several times at the beginning of your script will ensure it.
• If you decide to save all the output into a single folder, make the language code part of the screenshot and report file names to prevent them from overwriting.
  

Example #4: Availability Monitoring

Image Name	Image Description	Image
firefox_icon.png	Part of the Firefox "Go" icon.
apache.png	Part of the "Powered by Apache" logo image.

Example #5: Load Testing

1. Test script in the VNCRobot scripting language which will represent a typical user session with the tested application.
   
2. Java wrapper which will take advantage of the VNCRobot Open API to create and start parallel test threads.
3. Shell wrapper which will start and eventually shut down the VNC servers (Linux/Unix only).

import com.vncrobot.VNCRobot;
import com.vncrobot.api.VNCRobotThread;

/**
 * LoadExample.java
 *
 * This is an example of load testing based on VNCRobot. For more information 
 * read the How To Use VNCRobot document at 
 * http://www.vncrobot.com/docs/examples/index.html#example5
 * 
 * (C) 2007, Robert Pes
 */
public class LoadExample {
    
    // Default number of threads.
    final static int DEFAULT_THREAD_COUNT = 50;
    
    // Main method.
    public static void main(String[] argv) {
        
        // Number of threads
        int threadCount = DEFAULT_THREAD_COUNT;
        
        // Password
        String password = null;
        
        // Script path
        String script = null;
        
        // Parse the program arguments. We expect an integer
        // indicating how many threads we will start followed by script name.
        // The last argument, VNC password, is not mandatory because some 
        // VNC servers can be configured not to require authentication.
        if (argv.length > 1 && argv.length < 4) {
            try {
                threadCount = Integer.parseInt(argv[0]);
                script = argv[1];
                if (argv.length > 2) {
                    password = argv[2];
                }
            } catch (NumberFormatException ex) {
                System.out.println("Invalid number of threads - default of "+DEFAULT_THREAD_COUNT+" will be used.");
            }
        } else {
            System.out.println("Usage: LoadExample <number_of_threads> <script_path> [<VNC_password>]");
            return;
        }
        
        // Thread arguments. They are identical with VNCRobot CLI options.
        String[] threadArguments;
        if (password == null) {
            threadArguments = new String[] {
                "--connect",        // Connect option
                "",                 // VNC host name and port - will be generated dynamically
                "--run",            // Run option
                script,             // Name and path of the script to run
                "--nodisplay"       // CLI execution mode option
            };
        } else {
            threadArguments = new String[] {
                "--connect",        // Connect option
                "",                 // VNC host name and port - will be generated dynamically
                "--run",            // Run option
                script,             // Name and path of the script to run
                "--nodisplay",      // CLI execution mode option
                "--password",       // Password option
                password            // Password
            };
        }
        
        // Create an instance of VNCRobot
        VNCRobot robot = new VNCRobot();

        VNCRobotThread runnable;
        Thread thread;
        
        // Loop for index from 1 to specified number of threads
        for (int i=1; i<=threadCount; i++) {
            
            // Populate the VNC host name and port in the thread arguments
            threadArguments[1] = "localhost:" + i;
            
            // Create a new automated thread and start it
            runnable = robot.createVNCRobotThread(threadArguments[1], threadArguments, System.out, false);
            thread = new Thread(runnable);
            thread.start();
        }
    }
}