Lucene Full Text Search Indexing
================================

Requires Dovecot v2.1+ to work properly. The CLucene version must be v2.3 (not
v0.9).

Dovecot builds only a single Lucene index for all mailboxes. The Lucene indexes
are stored in 'lucene-indexes/' directory under the mail root index directory
(e.g.'~/Maildir/lucene-indexes/').

Configuration
-------------

---%<-------------------------------------------------------------------------
mail_plugins = $mail_plugins fts fts_lucene

plugin {
  fts = lucene
  # Lucene-specific settings, good ones are:
  fts_lucene = whitespace_chars=@.
}
---%<-------------------------------------------------------------------------

The fts-lucene settings include:

 * whitespace_chars=<chars>: List of characters that are translated to
   whitespace. You may want to use "@." so that e.g. in
   "'first.last@example.org'" it won't be treated as a single word, but rather
   you can search separately for "first", "last" and "example".
 * default_language=<lang>: Default stemming language to use for mails. The
   default is english. Requires that Dovecot is built with libstemmer, which
   also limits the languages that are supported.
 * textcat_conf=<path> textcat_dir=<path>: If specified, enable guessing the
   stemming language for emails and search keywords. This is a little bit
   problematic in practice, since indexing and searching languages may differ
   and may not find even exact words because they stem differently.

Libraries
---------

 * CLucene [http://sourceforge.net/projects/clucene/files/]: Get v2.3.3.4 (not
   v0.9)
 * libstemmer [http://snowball.tartarus.org/download.php]: Builds libstemmer.o,
   which you can rename to libstemmer.a
 * textcat [http://textcat.sourceforge.net/]

(This file was created from the wiki on 2013-08-05 04:42)
