Hello, SRU community.

To meet the searching needs of a new collection in our digital library, I was required to provide facet values to help refine search results.  Since we were using SRU as a middle layer between our repository and various collection-specific web applications, and this functionality seemed generally useful, the idea to create an SRU extension seemed appropriate.  We were able to extend an existing open source SRU implementation (big thanks to Ralph LeVan and the OCLC) to support this extended functionality with sufficient performance and what we consider to be a reasonable interface, but I am curious about the process for getting it listed as a registered extension.

Furthermore, it might be nice to see if the community had any suggestions or comments before we finalize the syntax so that it may be more generally useful.

A description of the extension with an example response is online on our wiki:
http://wiki.dlib.indiana.edu/confluence/display/INF/Faceted+Search

Later this month we will put the collection backed by the SRU/W server running this extension into production, and in the following weeks I hope to include this in a complete federated search of all collections using the dc and bib context sets.

Thanks for any feedback you can offer.

Michael Durbin
Indiana University Digital Library Program