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#!/usr/bin/env ruby # axi-query-expand - Query and show possible expansions # # Copyright (C) 2007 Enrico Zini <enrico@debian.org> # Copyright (C) 2008 Daniel Brumbaugh Keeney # # 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 require 'optparse' type = nil OptionParser.new do |opts| opts.program_name = 'axi-query-pkgtype.rb' opts.version = '0.1' opts.release = '1203587714' opts.banner = "Query the Apt Xapian index. Command line arguments can be keywords or Debtags tags" opts.on '-t', '--type TYPE', "package type, one of 'game', 'gui', 'cmdline' or 'editor'" do |v| type = v.to_sym end opts.on_tail("-h", "--help", "Show this message") do puts opts exit end end.parse! rescue ( puts 'try axi-query-pkgtype.rb --help'; exit 2 ) args = ARGV.collect do |i| i.dup; end # Import the rest here so we don't need dependencies to be installed only to # print commandline help require 'xapian' require 'aptxapianindex' # Instantiate a Xapian::Database object for read only access to the index db = Xapian::Database.new(XAPIANDB) # Build the base query as seen in axi-query-simple.rb query = Xapian::Query.new(Xapian::Query::OP_OR, terms_for_simple_query(args)) # Add the simple user filter, if requeste query = add_simple_filter_to_query(query, type) # Perform the query enquire = Xapian::Enquire.new(db) enquire.query = query # Retrieve the top 20 results matches = enquire.mset(0, 20) # Display the results show_mset(matches) # Now, we ask Xapian what are the terms in the index that are most relevant to # this search. This can be used to suggest to the user the most useful ways of # refining the search. # Select the first 10 documents as the key ones to use to compute relevant # terms rset = Xapian::RSet.new matches.matches.each do |m| rset.add_document m.docid end # This is the "Expansion set" for the search: the 10 most relevant terms eset = enquire.eset(10, rset) # Print it out. Note that some terms have a prefix from the database: can we # filter them out? Indeed: Xapian allow to give a filter to get_eset. # Read on... puts '' puts "Terms that could improve the search:" terms = eset.terms.collect do |res| "%s (%.2f%%)" % [res.name, res.weight] end puts terms.join(', ') terms = nil # You can also abuse this feature to show what are the tags that are most # related to the search results. This allows you to turn a search based on # keywords to a search based on semantic attributes, which would be an # absolutely stunning feature in a GUI. # We can do it thanks to Xapian allowing to specify a filter for the output of # get_eset. This filter filters out all the keywords that are not tags, or # that were in the list of query terms. class Filter < Xapian::ExpandDecider # Return true if we want the term, else false def __call__ term term[0..1] == "XT" end end # This is the "Expansion set" for the search: the 10 most relevant terms that # match the filter eset = enquire.eset(10, rset, Filter.new) # Print out the resulting tags puts '' puts "Terms that could improve the search:" terms = eset.terms.collect do |res| "%s (%.2f%%)" % [res.name[2..-1], res.weight] end puts terms.join(', ')