OpenSearchServer is a powerful, enterprise-class, search engine program. Using its Web user interface, crawlers (Web, file, database, etc.), and REST/RESTFul API, you can integrate advanced full-text search capabilities into your application.
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This second release candidate fixes the bugs identified in the first release candidate. One of the more interesting new features is the availability of an OpenSearchServer Drupal module. There are some interesting API improvements for file and Web crawling, as well as in the scheduler (with more information provided) and in the parser (with editable parameters). The addition of 2 very nice features: a sitemap generator and the ability to export the search result of any query into a CSV file for further analysis. Last but not least, the release of comprehensive online documentation.