Sanjiv Singh is a Python developer from New Delhi, India who contributes to the TurboGears and Toscawidgets projects. Singh recently gave a talk on “TurboGears2 Geopspatial Framework at PyCon 2010, which is a framework for developing Geographic Information System Applications, such as the Blind Audio Tactile System.

Q: What is the relationship between a GIS application and a Geospatial framework?

Sanjiv Singh: A GIS application is any software application that deals with information pertaining to “location” or “geometry” of objects and is capable of:
(a) processing such information, such as finding out objects located within 100m raduis of another
(b) displaying such information, such as showing objects on a map

A Geospatial Framework, on the other hand, is a collection of programs that work in an integrated manner towards easily developing GIS applications. The word Geospatial is a more formal term for what we commonly refer to as GIS.

Q: Did you develop the Turbogears Geospatial Framework?

Sanjiv Singh: Yes and No. The framework consists of many different python gis applications / libraries such as featureserver, mapfish, tilecache, Shapely, GeoJSON, etc. These are developed and maintained by other developers. However, I integrated these applications with the TurboGears2 Web Framework so that TurboGears developers may now develop GIS applications easily. I also contributed significantly to GeoAlchemy which is an extension of SQLAlchemy, the python database toolkit for GIS applications. GeoAlchemy now forms the ORM layer of the TG2 Geospatial Framework.

Q: Why didn’t you choose Django, which has the GeoDjango framework readily available?

Sanjiv Singh: GeoDjango is a matured GIS framework, however, it is meant for Django applications. Having developed several applications using TurboGears, I did not want to re-implement existing applications or to learn another framework. So I used several Python gis libraries with my TurboGears applications to make them do Geospatial work. So, in order to make it easier for other TurboGears developers to use GIS I integrated these libraries through a new TG2 extension called tgext.geo. This extension along with GeoAlchemy now works as a Geospatial Framework.

More Resources

Sanjiv Sighn’s Open Source Projects http://www.ohloh.net/accounts/sanjiv
Sanjiv Singh’s PyCon Presentation (Including Slides) http://us.pycon.org/2010/conference/schedule/event/16/
Sanjiv Singh’s Blog http://sanjiv-singh.blogspot.com/

TurboGears http://turbogears.org/
Toscawidgets http://toscawidgets.org/