Gists

I want to get this code merged in so I can move on to more interesting stuff in the UI. Currently this supports "snapshotting" a graph which in turn grabs the raw data used to construct the graph and saves it in the database for later retrieval. It also stores the url and configuration data reflecting the state of the "gisted" graph at the time of capture. This can be used at a later date to recreate the original state of the graph, regardless of any future configuration changes or loss of resolution to the original graph.

In order for this to become a full-fledged feature we need to add support for real client-side graph rendering in Descartes via D3 or Rickshaw. With that in place we can do some more interesting stuff with this saved data. Until then...