I'm not sure if you'll find exactly what you're looking for, but this tool can be extremely helpful in analyzing TWB workbooks in a directory:
It's a real hack, and quite brittle, but one approach is to programmatically operate Tableau Desktop. This put the full power of Tableau Desktop into play - anything you can do with it can be automated, including accessing a viz that uses the TDE and downloading or exporting the data, whichever suits your purpose.
I've done this a few times using Sikuli, Sikuli Script - Home, which accesses the Windows windowing system and can programmatically drive pretty much any Windows app.
It's been a fair while since I've done it and I don't have the details at hand, but here's the basic flow:
- create a Tableau workbook that has the content you want
- run through the steps of getting Tableau Desktop to do what you want, to the point where it's a mechanical process that doesn't require any variable user input
- create the Sikuli script that mimics these steps
Naturally, the devil is in the details, and there are plenty of them.
Still, it's not all that difficult, just takes a little time and experimenting.
Sikuli can integrate Python code, and if member serves other languages. But not Ruby, when I was working with it.
I thought about putting a blog post about this after I'd done it a couple of times, but work got in the way.
It just might work for you.