TYPO3 is an Open Source Content Management System that is very popular in Europe, especially in the German market, and gaining traction in the U.S., too.
TYPO3 is a good example of how to integrate Solr with a CMS. The challenges we faced are typical of any CMS integration. We came up with solutions and ideas to these challenges and our hope is that they might be of help for other CMS integrations as well.
That includes content indexing, file indexing, keeping track of content changes, handling multi-language sites, search and facetting, access restrictions, result presentation, and how to keep all these things flexible and re-usable for many different sites.
For all these things we used a couple additional Apache projects and we would like to show how we use them and how we contributed back to them while building our Solr integration.