lib/multi_index.rb

   1 module FerretMixin
   2   module Acts #:nodoc:
   3     module ARFerret #:nodoc:
   4       # not threadsafe
   5       class MultiIndex
   6
   7         # todo: check for necessary index rebuilds in this place, too
   8         # idea - each class gets a create_reader method that does this
   9         def initialize(model_classes, options = {})
  10           @model_classes = model_classes
  11           @options = {
  12             :default_field => '*',
  13             #:analyzer => Ferret::Analysis::WhiteSpaceAnalyzer.new
  14             :analyzer => Ferret::Analysis::StandardAnalyzer.new
  15           }.update(options)
  16         end
  17
  18         def search(query, options={})
  19           #puts "querystring: #{query.to_s}"
  20           query = process_query(query)
  21           #puts "parsed query: #{query.to_s}"
  22           searcher.search(query, options)
  23         end
  24
  25         def search_each(query, options = {}, &block)
  26           query = process_query(query)
  27           searcher.search_each(query, options, &block)
  28         end
  29
  30         # checks if all our sub-searchers still are up to date
  31         def latest?
  32           return false unless @reader
  33           # segfaults with 0.10.4 --> TODO report as bug @reader.latest?
  34           @sub_readers.each do |r|
  35             return false unless r.latest?
  36           end
  37           true
  38         end
  39
  40         def searcher
  41           ensure_searcher
  42           @searcher
  43         end
  44
  45         def doc(i)
  46           searcher[i]
  47         end
  48         alias :[] :doc
  49
  50         def query_parser
  51           ensure_searcher
  52           unless @query_parser
  53             @query_parser ||= Ferret::QueryParser.new(@options)
  54           end
  55           @query_parser.fields = @reader.field_names
  56           @query_parser
  57         end
  58
  59         def process_query(query)
  60           query = query_parser.parse(query) if query.is_a?(String)
  61           return query
  62         end
  63
  64         def close
  65           @searcher.close if @searcher
  66           @reader.close if @reader
  67         end
  68
  69         protected
  70
  71           def ensure_searcher
  72             unless latest?
  73               @sub_readers = @model_classes.map { |clazz|
  74                 begin
  75                   reader = Ferret::Index::IndexReader.new(clazz.class_index_dir)
  76                 rescue Exception
  77                   puts "error opening #{clazz.class_index_dir}: #{$!}"
  78                 end
  79                 reader
  80               }
  81               close
  82               @reader = Ferret::Index::IndexReader.new(@sub_readers)
  83               @searcher = Ferret::Search::Searcher.new(@reader)
  84             end
  85           end
  86
  87       end # of class MultiIndex
  88
  89     end
  90   end
  91 end