Koha/Indexer/Utils.pm

   1 package Koha::Indexer::Utils;
   2
   3 # Copyright (c) 2012 Equinox Software, Inc.
   4 # This file is part of Koha.
   5 #
   6 # Koha is free software; you can redistribute it and/or modify it under the
   7 # terms of the GNU General Public License as published by the Free Software
   8 # Foundation; either version 2 of the License, or (at your option) any later
   9 # version.
  10 #
  11 # Koha is distributed in the hope that it will be useful, but WITHOUT ANY
  12 # WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  13 # A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License along with
  16 # Koha; if not, write to the Free Software Foundation, Inc.,
  17 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18
  19 use strict;
  20 use warnings;
  21 use 5.010;
  22
  23 use XML::LibXML;
  24
  25 =head1 Koha::Indexer::Utils
  26
  27 Koha::Indexer::Utils - utility functions for managing search indexes
  28
  29 =head1 DESCRIPTION
  30
  31 This modules contains utility functions for managing various aspects
  32 of Koha's bibliographic and authority search indexes.
  33
  34 =head1 FUNCTIONS
  35
  36 =cut
  37
  38 =head2 zebra_record_abs_to_dom
  39
  40 $dom_config = Koha::Indexer::Utils::zebra_record_abs_to_dom($record_abs_config, $marcflavour);
  41
  42 Given a string containing the contents of a records.abs configuration file as
  43 used by Zebra's GRS-1 filter, emit an equivalent DOM configuration.
  44
  45 =cut
  46
  47 our $idxNS = 'http://www.koha-community.org/schemas/index-defs';
  48
  49 sub zebra_record_abs_to_dom {
  50     my $grs1_cfg = shift;
  51     my $marcflavour = shift;
  52
  53     chomp $grs1_cfg;
  54     my @grs1_cfg_lines = split /\n/, $grs1_cfg, -1;
  55     my $grs1_defs = [];
  56
  57     # generate an arrayref of structures representing
  58     # each records.abs line
  59     for (my $i = 0; $i <= $#grs1_cfg_lines; $i++) {
  60         my $line = $grs1_cfg_lines[$i];
  61         next if _can_ignore_grs1_cfg_line($line);
  62         my $grs1_def = _parse_grs1_cfg_line($line);
  63         $grs1_def->{orig_def} = $line;
  64         $grs1_def->{lineno} = $i + 1;
  65         push @$grs1_defs, $grs1_def;
  66     }
  67
  68     # map the index definitions to a DOM tree representing
  69     # the index definitions -- if you squint hard, you
  70     # can see the beginnings of a more general definition language
  71     # for Koha index definitions
  72     my $dom_cfg = XML::LibXML::Document->new('1.0', 'utf-8');
  73     my $root = $dom_cfg->createElement('index_defs');
  74     $root->setNamespace($idxNS, 'kohaidx');
  75     foreach my $grs1_def (@$grs1_defs) {
  76         _append_grs1_def_to_dom_cfg($dom_cfg, $root, $grs1_def, $marcflavour);
  77     }
  78
  79     # and emit the result as a string
  80     $dom_cfg->setDocumentElement($root);
  81     return $dom_cfg->toString(1);
  82 }
  83
  84 #
  85 # bunch of utility functions for zebra_record_abs_to_dom
  86 #
  87 sub _can_ignore_grs1_cfg_line {
  88     my $line = shift;
  89     return 1 if $line =~ /^\s*$/ or
  90                 $line =~ /^#/ or
  91                 $line =~ /^(encoding|name|attset|esetname|marc|systag|xpath)/ or
  92                 $line =~ /^all/; # DOM filter automatically indexes all tokens, so
  93                                  # no need to deal with 'all any' lines in record.abs
  94     return 0;
  95 }
  96
  97 sub _parse_grs1_cfg_line {
  98     my $line = shift;
  99     my $grs1_def;
 100
 101     if ($line =~ /^melm\s+(.*)/ || $line =~ m!^xelm /record/(.*)!) {
 102         $grs1_def = _parse_xelm_melm($1);
 103     }
 104     return $grs1_def;
 105 }
 106
 107 sub _parse_xelm_melm {
 108     my $line = shift;
 109
 110     my ($field, $index_defs) = split /\s+/, $line, 2;
 111
 112     # munge fixed field range indicators
 113     $index_defs =~ s/range\(data,(\d+),(\d+)\)/$1:$2/g;
 114
 115     my ($tag, $subfield) = split /\$/, $field, 2;
 116     return {
 117         tag         => $tag,
 118         subfield    => $subfield,
 119         index_defs  => [ map { _parse_grs1_index_def($_) } split /,/, $index_defs ],
 120     };
 121 }
 122
 123 sub _parse_grs1_index_def {
 124     my $index_def = shift;
 125
 126     my @parts = split /:/, $index_def, -1;
 127     my $parsed_def = {};
 128     $parsed_def->{name}       = shift @parts;
 129     $parsed_def->{index_type} = shift @parts;
 130     $parsed_def->{offset}     = shift @parts;
 131     $parsed_def->{length}     = shift @parts;
 132     # if the original index definition didn't specify an index
 133     # type, set it 'w' -- the DOM filter needs the index type
 134     # to be specified explicitly
 135     $parsed_def->{index_type} = 'w' unless defined $parsed_def->{index_type};
 136     return $parsed_def;
 137 }
 138
 139 sub _append_grs1_def_to_dom_cfg {
 140     my $dom_cfg = shift;
 141     my $root = shift;
 142     my $grs1_def = shift;
 143     my $marcflavour = shift;
 144
 145     my $comment = $dom_cfg->createComment('record.abs line ' .
 146                                           $grs1_def->{lineno} . ': ' .
 147                                           $grs1_def->{orig_def});
 148     $root->appendChild($comment);
 149
 150     if (defined $grs1_def->{tag} && defined $grs1_def->{subfield}) {
 151         my $dom_def = $dom_cfg->createElementNS($idxNS, 'index_subfields');
 152         $dom_def->setAttribute('tag', $grs1_def->{tag});
 153         $dom_def->setAttribute('subfields', $grs1_def->{subfield});
 154         _append_target_indexes($dom_cfg, $dom_def, $grs1_def);
 155         $root->appendChild($dom_def);
 156     } elsif (defined $grs1_def->{tag} and $grs1_def->{tag} eq 'leader') {
 157         # we're the leader
 158         _append_grs1_defs_for_leader($dom_cfg, $root, $grs1_def);
 159     } elsif (defined $grs1_def->{tag} and $grs1_def->{tag} < 10) {
 160         # we're a control field
 161         _append_grs1_defs_for_control_field($dom_cfg, $root, $grs1_def);
 162     } elsif (defined $grs1_def->{tag}) {
 163         # we're indexing an entire variable data field
 164         my $dom_def = $dom_cfg->createElementNS($idxNS, 'index_data_field');
 165         $dom_def->setAttribute('tag', $grs1_def->{tag});
 166         _append_target_indexes($dom_cfg, $dom_def, $grs1_def);
 167         $root->appendChild($dom_def);
 168     }
 169 }
 170
 171 sub _append_target_indexes {
 172     my $dom_cfg = shift;
 173     my $dom_def = shift;
 174     my $grs1_def = shift;
 175
 176     foreach my $index_def (@{ $grs1_def->{index_defs} }) {
 177         _append_one_target_index($dom_cfg, $dom_def, $index_def);
 178     }
 179 }
 180
 181 sub _append_one_target_index {
 182     my $dom_cfg = shift;
 183     my $dom_def = shift;
 184     my $index_def = shift;
 185     my $tgt_idx = $dom_cfg->createElementNS($idxNS, 'target_index');
 186     my $index_name = "$index_def->{name}:$index_def->{index_type}";
 187     $tgt_idx->appendText($index_name);
 188     $dom_def->appendChild($tgt_idx);
 189 }
 190
 191 sub _append_grs1_defs_for_leader {
 192     my $dom_cfg = shift;
 193     my $root = shift;
 194     my $grs1_def = shift;
 195     foreach my $index_def (@{ $grs1_def->{index_defs} }) {
 196         my $dom_def = $dom_cfg->createElementNS($idxNS, 'index_leader');
 197         if (defined $index_def->{offset} && defined $index_def->{length}) {
 198             $dom_def->setAttribute('offset', $index_def->{offset});
 199             $dom_def->setAttribute('length', $index_def->{length});
 200         }
 201         _append_one_target_index($dom_cfg, $dom_def, $index_def);
 202         $root->appendChild($dom_def);
 203     }
 204 }
 205
 206 sub _append_grs1_defs_for_control_field {
 207     my $dom_cfg = shift;
 208     my $root = shift;
 209     my $grs1_def = shift;
 210     foreach my $index_def (@{ $grs1_def->{index_defs} }) {
 211         my $dom_def = $dom_cfg->createElementNS($idxNS, 'index_control_field');
 212         $dom_def->setAttribute('tag', $grs1_def->{tag});
 213         if (defined $index_def->{offset} && defined $index_def->{length}) {
 214             $dom_def->setAttribute('offset', $index_def->{offset});
 215             $dom_def->setAttribute('length', $index_def->{length});
 216         }
 217         _append_one_target_index($dom_cfg, $dom_def, $index_def);
 218         $root->appendChild($dom_def);
 219     }
 220 }
 221
 222 1;