How to fully automate creation and initial config of Ubuntu VM in Azure Virtual Machines?

Hi,

Can anyone share some pointers on what is the best way to automate (as in scripting - CMD, PowerShell, Node.JS, Python) the process to create and setup a Ubuntu VM in Azure Virtual Machines?

The ideal would be something to be able have a simple

     my-wonder-script  c:\work\my-vm-config.xml 

I already know how to create a VM via Azure client tools, but I haven't found a way to feed it a simple XML file with all azure-specific configs.

Also, how can I configure "cloud-init" data? In AWS EC2 one can configure "user data" and cloud-init picks it up.

I could not find any similar mechanism in Azure to do the initial config of the machine (from ssh keys to apt-get install packages).

Thanks,

Joao