This sounds cool! I had a discussion with some coworkers yesterday, who were asking me how long Hobbit keeps its data. I showed them how the rrd files kept data for 576 days. They then asked me how we could retain data longer than that. I was thinking we could periodically (every quarter?) archive the rrd files to another dir or storage, and start fresh. They then asked me how we would look at those graphs from older archived rrd files, to which I am not sure.
It sounds to me like your tool could be an answer, if it could be modified to use an alternate location of rrd files. This would allow viewing older data that was no longer accessible via the normal Hobbit interface.
I can check what can be done... I've to check if using the standard hobbitgraph cgi it's possible to make it read the data in another directory (I think it should be possible) and then It will be also possible to get data from another source. For our routers we've archived rrd files generated by rrd of last 15 days, and then we have archived 1 rrd file for the 1st of each month just to go back and check what was happening in the past and if the traffic really changed during a normal working day/week.
I'll check if it's possible to do something about.
Francesco