How to clone VirtualBox virtual machine

VirtualBox is great piece of software for virtualization. I like it more than VMWare or VirtualPC. The downside of it is its lack of easy cloning or copying capabilities. There are none. And because everything in VirtualBox has UUID (guid), pure file copy does not work well.

All advices I have seen were about: create the new virtual machine manually, clone HDD .vdi file with  VBoxManage clonevdi command and attach it to the newly created virtual machine. Manually!?

That's why I've created a simple Python script that cares about exporting and importing virtual machines (Thanks for the VirtualBox 3 SDK!). When exporting, you can select the virtual machine and snapshot you want to export:

The exported machines are stored in exp folder at the script file. The time stamp is added to the machine name for unique identification. When importing, you are offered with the saved virtual machines and you simply choose one. Of course you can copy the exported machine to different computer (having the same VirtualBox versions is recommended).

The script is very simple and targeted to my needs. That means it exports only primary HDD and network adapter 0. It does not export CD/DVD-ROM, Floppy nor Serial ports.

Try it and let me know whether it's helpful: download script (it requires ConfigObj 4).

Update 1. 10. 2009: I struggled running the script on my new Win 7 64-bit system. It complained class is not registered for VirtualBox.Session. The reason was mixing 32-bit and 64-bit programs - see the explanation. If you use 64-bit OS, you have to have installed 64-bit version of Python and pywin32!

Update 11. 11. 2009: I have updated the script to better serve my needs. For example, when restoring virtual machine, you can enter a new name for it. Be carefull when restoring one saved machine to two new ones as you have to chagne MAC address manually.

Unfortunately, the old config file is not compactible with the new version. But I think you can guess from the Python exception what is wrong with the config file and fix it. The old version is still available.

Update 29. 12. 2009: When I upgraded to VirtualBox 3.1, I received KeyError when I run my script ({2158464A-F706-414B-A8C4-FB589DFC6B62}). To get rid of it, delete all from from \Python26\Lib\site-packages\win32com\gen_py\ except __init__.py.

Pycon 2009: Functional Testing of Desktop Applications

Here is a link to Michael Foord talk at Pycon 2009 in Chicago about functional testing of desktop applications:

Functional Testing of Desktop Applications
Many advocates of unit testing believe that testing desktop (GUI) applications is so difficult as to not be worth it. Not only is it possible, but 'functional testing' (testing an application from the point of view of the user) is an important part of an agile development process.

I watched it yesterday and it is very good!

Testing an unknown application

From time to time you may need to test an unknown application. I have encounter it when I needed to test our installation program. The task was simple - install the application for automated smoke tests. In such cases I gladly return to Accessibility.

Let's pretend our testing application is not written in .NET and the only way how to explore it is through the accessibility (AccExplorer):

All we need to do is to access Accessibility objects from IronPython. There is a project called Managed Windows API that nicely wraps accessibility for .NET. It also wraps other Win32 API calls (mouse clicks etc.) but I stay with Win32API.dll because of my laziness :-).

Utilizing the Managed Windows API you can control the accessibility objects. Here is the snippet:

import clr
# Win32API provide access to Win32 API functions
clr.AddReference('Win32API')
from Win32API import Win32API
# ManagedWinapi provide access to Accessibility objects
clr.AddReference('ManagedWinapi')
import ManagedWinapi.Accessibility as ma
import ManagedWinapi.Windows as mw

def GetGUIATWindow():
   """ Return GUIAT_PoC window accessibility object. """
   def callback(aWindow):
       return aWindow.Title == 'GUIAT - Proof of Concept'
   guiat_window = mw.SystemWindow.FilterToplevelWindows(callback)
   # assume guiat_window is list with just one object
   return ma.SystemAccessibleObject.FromWindow(guiat_window[0],
       ma.AccessibleObjectID.OBJID_WINDOW)

guiat_acc = GetGUIATWindow()
# position of the 'New listbox item' text box
pos = guiat_acc.Children[3].Children[1].Location
# focus the text box
Win32API.MouseClick(pos.X + pos.Width/2, pos.Y + pos.Height/2)
Win32API.SendString('Accessibility test')
# position of the 'Add Item' button
pos = guiat_acc.Children[3].Children[2].Location
# click the button
Win32API.MouseClick(pos.X + pos.Width/2, pos.Y + pos.Height/2)

To run it, download managedwinapi-0.3.zip and extract the ManagedWinapi.dll to the same folder as the source code.

When you run the code, it enters Accessibility test text into New listbox item text box and clicks Add Item button. The controls are always on the same position within the Children enumeration so we can use direct referencing: e.g. guiat_acc.Children[3].Children[2] is the button accessibility object.

Enhancing this example is up to you - I have created several functions that take care about entering the text into text boxes, selecting buttons or a checking check boxes. That's all I need to create a script that installs our application.