Ferret is a Ruby search library inspired by the Apache Lucene search engine for Java (jakarta.apache.org/lucene/). In the same way as Lucene, it is not a standalone application, but a library you can use to index documents and search for things in them later.


  • Ruby 1.8

  • C compiler to build the extension. Tested with gcc, VC6

  • make (or nmake on windows)


$ sudo gem install ferret

If you don't have rubygems installed you can still install Ferret. Just download one of the zipped up versions of Ferret, unzip it and change into the unzipped directory. Then run the following set of commands;

$ ruby setup.rb config
$ ruby setup.rb setup
$ sudo ruby setup.rb install


You can read the TUTORIAL which you'll find in the same directory as this README. You can also check the following modules for more specific documentation.

  • Ferret::Analysis: for more information on how the data is processed when it is tokenized. There are a number of things you can do with your data such as adding stop lists or perhaps a porter stemmer. There are also a number of analyzers already available and it is almost trivial to create a new one with a simple regular expression.

  • Ferret::Search: for more information on querying the index. There are a number of already available queries and it's unlikely you'll need to create your own. You may however want to take advantage of the sorting or filtering abilities of Ferret to present your data the best way you see fit.

  • Ferret::Document: to find out how to create documents. This part of Ferret is relatively straightforward. If you know how Strings, Hashes and Arrays work Ferret then you'll be able to create Documents.

  • Ferret::QueryParser: if you want to find out more about what you can do with Ferret's Query Parser, this is the place to look. The query parser is one area that could use a bit of work so please send your suggestions.

  • Ferret::Index: for more advanced access to the index you'll probably want to use the Ferret::Index::IndexWriter and Ferret::Index::IndexReader. This is the place to look for more information on them.

  • Ferret::Store: This is the module used to access the actual index storage and won't be of much interest to most people.


We are unaware of any alternatives that can out-perform Ferret while still matching it in features.


For bug reports and patches I have set up Trac here;


Queries, discussion etc should be addressed to the mailing lists here;


Alternatively you could create a new page for discussion on the Ferret wiki;


Of course, since Ferret was ported from Apache Lucene, most of what you can do with Lucene you can also do with Ferret.


David Balmain

Port to Ruby

The Apache Software Foundation (Doug Cutting and friends)

Original Apache Lucene


Ferret is available under an MIT-style license.

:include: MIT-LICENSE