Current Path : /usr/share/doc/apt-xapian-index/examples/ruby/ |
Current File : //usr/share/doc/apt-xapian-index/examples/ruby/axi-query-simple.rb |
#!/usr/bin/env ruby # # axi-query-simple - apt-cache search replacement using apt-xapian-index # # Copyright (C) 2007 Enrico Zini <enrico@debian.org> # Copyright (C) 2008 Daniel Brumbaugh Keeney <devi.webmaster@gmail.com> # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA # http://svn.debian.org/wsvn/collab-maint/deb-maint/apt-xapian-index/trunk/examples/axi-query-simple.py?op=file&rev=5455&sc=0 require 'xapian' # Setup configuration XAPIANDBPATH = "/var/lib/apt-xapian-index" XAPIANDB = XAPIANDBPATH + "/index" # Instantiate a xapian.Database object for read only access to the index db = Xapian::Database.new( XAPIANDB ) # Stemmer function to generate stemmed search keywords stemmer = Xapian::Stem.new 'english' # Build the terms that will go in the query terms = [] ARGV.each do |word| word = word.dup if not word.downcase! and word['::'] # If it's lowercase and it contains '::', then we consider it a Debtags # tag. A better way could be to look up arguments in # /var/lib/debtags/vocabulary # # According to /var/lib/apt-xapian-index/README, Debtags tags are # indexed with the 'XT' prefix. terms << ( 'XT' << word ) else # If it is not a Debtags tag, then we consider it a normal keyword. terms << word # If the word has a stemmed version, add it to the query. # /var/lib/apt-xapian-index/README tells us that stemmed terms have a # 'Z' prefix. stem = stemmer.call(word) terms << ('Z' << stem) unless stem == word end end # OR the terms together into a Xapian query. # # One may ask, why OR and not AND? The reason is that, contrarily to # apt-cache, Xapian scores results according to how well they matched. # # Matches that math all the terms will score higher than the others, so if we # build an OR query what we really have is an AND query that gracefully # degenerates to closer matches when they run out of perfect results. # # This allows stemmed searches to work nicely: if you look for 'editing', then # the query will be 'editing OR Zedit'. Packages with the word 'editing' will # match both and score higher, and packages with the word 'edited' will still # match 'Zedit' and be included in the results. query = Xapian::Query.new(Xapian::Query::OP_OR, terms) # Perform the query enquire = Xapian::Enquire.new db enquire.query = query # Display the top 20 results, sorted by how well they match matches = enquire.mset(0, 20) puts "%i results found." % matches.matches_estimated puts "Results 1-%i:" % matches.size matches.matches.each do |m| # /var/lib/apt-xapian-index/README tells us that the Xapian document data # is the package name. name = m.document.data # Get the package record out of the Apt cache, so we can retrieve the short # description #pkg = Apt::cache[name] # Print the match, together with the short description puts "%i%% %s - %s" % [m.percent, name, 'summary not available'] end