dynamic_reconfigure with programatically filled enum?

edit

Hey ROS gurus. I want to ask you for your opinions to a topic I recently thought about.

I'm writing a ROS&Python driver for a series of web cameras. There is a lot of variability in the specific models, including supported image resolutions.

Now I want to offer a dynamic_reconfigure interface for setting (not only) video resolution. My basic thought was to filter a list of possible resolutions somehow to only publish the supported resolutions on parameter_descriptions (thus displaying only them in rqt_reconfigure).

But then I found out that even the set of possible resolutions is not bound and new resolutions may emerge with new camera models.

I have 2 ideas on what to do with that:

• alter dynamic_reconfigure and create another edit_method (that's lot of work, though)
• create my own implementation of dynamic_reconfigure.Server, which would read the allowed resolutions from somewhere and would publish the corresponding parameter_descriptions. In the cfg file I would probably create a dummy one-element enum in order not to stop existing tools from working.

I'm only concerned about this solution working from dynamic_reconfigure CLI, rqt_reconfigure and Python (ideally using the standard Client). I don't (yet) care about C++ clients.

Before I start working, could you please give me some feedback on how you like these ideas and what possible shortcomings do you see?