Google Hacks, 2nd Edition

Build Google Directory URLs

Use ODP category information to build URLs for the Google Directory.

The Google Directory (http://directory.google.com) overlays the Open Directory Project (ODP or DMOZ, http://www.dmoz.org) ontology onto the Google core index. The result is a Yahoo!-like directory hierarchy of search results and their associated categories with the added magic of Google’s popularity algorithms.

The ODP opens its entire database of listings to anybody—provided you’re willing to download a 283 MB file (and that’s compressed!). While you’re probably not interested in all the individual listings, you might want particular ODP categories, or you may be interested in watching new listings flowing into certain categories.

Unfortunately, the ODP does not offer a way to search by keyword sites added within a recent time period. So instead of searching for recently added sites, the best way to get new site information from the ODP is to monitor categories.

Because the Google Directory builds its directory based on the ODP information, you can use the ODP category hierarchy information to generate Google Directory URLs. This hack searches the ODP category hierarchy information for keywords that you specify, and then builds Google Directory URLs and checks to make sure that they’re active.

You’ll need to download the category hierarchy information from the ODP to get this hack to work. The compressed file containing this information is available from http://dmoz.org/rdf.html, and the ...