This is a Lucene-based mail indexer that can be used with Gnus and
nnir.el--the first non-trivial Clojure program I wrote.  Ah, memories.
Having really fast search over all of your mail is hard to beat.


Building it
-----------

The usual steps:

  1.  Get Leiningen from http://github.com/technomancy/leiningen and put
      the 'lein' script somewhere in your $PATH.

  2.  From mailindex's root directory, run `lein uberjar'.  Lein will grab
      all required dependencies and produce a `mailindex.jar'.


Running it
----------

You will need to define your own "config.clj" file--mine is included for
reference.  This contains global options (which port to listen on, where
to store your Lucene indexes, etc.) as well as a list of backends that
will be scanned for messages.  I use Gnus's nnml backend, so that should
work out of the box, but you can add other backends by adding more
files.  Just use nnml.clj as a guide.

To run the thing, see the "mailindex" shell script--that's how I run
mine.

The first time you run mailindex it will run off and index all of your
mail.  Once it has finished this, you can search it just by telnetting
to its port and typing your query.  For example:

  $ telnet localhost 4321
  Trying 127.0.0.1...                                       
  Connected to localhost.
  Escape character is '^]'.

  from:triggs clojure

  (["misc" "6888" 18178 <headers>] ["misc" "7237" 14001 <headers>]
   ["misc" "7440" 14001 <headers>] ["misc" "6908" 13526 <headers>]
   ["misc" "69914" 9401 <headers>] ["misc" "7598" 6751 <headers>]
   ["work" "76803" 6751 <headers>] ["misc" "6877" 6031 <headers>]
   ["misc" "75410" 3502 <headers>] ["work" "74509" 3502 <headers>])

Mailindex returns a bunch of 4-tuples representing matching messages.
These consist of: the group of the message, the message number, the
relevance score, and the message headers.  Results are sorted in
descending order of relevance.


Integrating with Gnus/nnir
--------------------------

"contrib/mailindex.el" contains the configuration I use for integrating
with Gnus.  Put this into your emacs load-path, add (require 'mailindex)
to your ~/.emacs, and then hitting 'G G' from Gnus's group buffer should
prompt you for a query string, fire off a search and display an
ephemeral group with matching results.  I submitted a patch to nnir.el
to have it pull the headers straight from the data returned (which is
much faster than hitting the disk), but you can also grab nnir.el from
the "contrib" directory if you're not using a recent version of Gnus.


The query syntax
----------------

Query syntax is Lucene's standard syntax, although I do attempt to be
clever and munge queries on the fly to improve the result ordering.
Some examples:

  # Messages with a sender containing 'triggs' and the word 'clojure
  # anywhere
  from:triggs clojure

  # Anything sent between June 2008 and January 2009 containing the word
  # 'porcupine'
  date:[200806 TO 200901] porcupine

  # Boolean madness
  from:triggs AND (to:clojure OR to:vufind) AND subject:pickles


Licence
-------

Distributed under the Eclipse Public License. See the file "COPYING".