Want to know what's in your Workbooks? Need to make changes to them programmatically? Many of us do.
For the past six+ years I've been building tools that do this, and there are other tools out there. But they have the same limitations: they're fixed-function; they're external to Tableau; they're not open; some of them are even expensive.
Tired of creating the same functional code over and over, I've created a Ruby library to do the heavy lifting involved in Workbook analysis and manipulation, and released it to the public as an Open Source Ruby gem.
It's available on GitHub here: ChrisGerrard/TWB · GitHub
(The tools that predate the gem may or may not be rewritten to do so, depending upon time available, best intentions, other commitments, etc.)
This post: http://tableaufriction.blogspot.ca/2015/04/fast-easy-free-workbook-documentation.html describes Twb, the Ruby gem, and provides an introductory example of it in use.
More useful apps are in the pipeline, and will be published (very soon I hope), If you have any ideas or needs for useful and valuable apps please drop a comment here or at Tableau Friction.