Many of us probably deal with a lot of geodata that significantly evolve over time, the need for geodata versioning mechanisms is clearly a major one in many sectors. About a year ago we mentioned OpenGeo's GeoGit project, and now OpenGeo shared their vision for distributed versioning of geospatial data. This is important stuff.
In addition to this intro, here's the 3-part series:
From their introduction: "As opposed to spatial data being be locked-up in a single machine or database, we see a future where it could live in a collaborative infrastructure that can track data’s origin and evolution, much like source code. [...] A distributed version control model can better address such problems as collaborating between users or organization, maintaining authoritative data, and enabling offline, low-bandwidth, or intermittent connectivity."
You probably know what Git is, the modern distributed revision control system, replacing CVS and Subversion for many projects. Spatially Adjusted made me aware of the GeoGit approach.
Here's what the documentation written a month ago says: "Following on the core Versioning WFS work, in 2011 OpenGeo started experimenting with a new way to handle versioning, drawing on git, a distributed versioning system built for Linux and widely used. There are two different paths taken, both of which warrant further investigation:
The code for the core repository can be found at https://github.com/opengeo/GeoGIT . This code backs both a GeoSynchronization Service module (a spec by the OGC to synchronize data) and the versioning constructs of WFS2. The plan is to eventually get both in to the standard distributions of GeoServer.
For the geogit implementation we instead code things to be optimized for the fact that a typical geospatial representation doesn't have much nesting - it's just a bunch of features. The index is orthogonal, doesn't need to be part of the tree structure. But the problem we had when we tried to use straight git with lots of leafs is that it wouldn't really work. It doesn't scale to a single directory with millions of files."
Here's a few recent open source-related geospatial news: