source: main/trunk/greenstone2/perllib/plugins/MetadataXMLPlugin.pm@ 28836

Last change on this file since 28836 was 28836, checked in by ak19, 7 years ago

A question on the mailing list involved accented characters in custom metadata set names (not metadata set values). This exposed an issue in greenstone that could not cope with utf8 characters in metaset names. The cause was the sub Char { use bytes; ... lines when reading XML. These needed to be commented out in both MetadataXMLPlugin and ReadXMLFile (as GreenstoneXMLPlugin inherits from ReadXMLFile). Doing so showed that extra Encode::decode() operations to decode strings read in from XML into utf8 were no longer needed. As a result MetaXMLPlug and GreenstoneXMLPlug no longer call decode on the metadaname name and value read in from XML, or for the full-text, since GreenstoneXMLPlugin in entirety now no longer does the 'use bytes' part. Tested with text and html collections where metadata set nanes created in custom .mds files, their assigned metadata values and a document's full-text all contained the utf-8 specific character of a-macron.

  • Property svn:keywords set to Author Date Id Revision
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1###########################################################################
2#
3# MetadataXMLPlugin.pm --
4# A component of the Greenstone digital library software
5# from the New Zealand Digital Library Project at the
6# University of Waikato, New Zealand.
7#
8# Copyright (C) 2006 New Zealand Digital Library Project
9#
10# This program is free software; you can redistribute it and/or modify
11# it under the terms of the GNU General Public License as published by
12# the Free Software Foundation; either version 2 of the License, or
13# (at your option) any later version.
14#
15# This program is distributed in the hope that it will be useful,
16# but WITHOUT ANY WARRANTY; without even the implied warranty of
17# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18# GNU General Public License for more details.
19#
20# You should have received a copy of the GNU General Public License
21# along with this program; if not, write to the Free Software
22# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23#
24###########################################################################
25
26# MetadataXMLPlugin process metadata.xml files in a collection
27
28# Here's an example of a metadata file that uses three FileSet structures
29# (ignore the # characters):
30
31#<?xml version="1.0" encoding="UTF-8" standalone="no"?>
32#<!DOCTYPE DirectoryMetadata SYSTEM "http://greenstone.org/dtd/DirectoryMetadata/1.0/DirectoryMetadata.dtd">
33#<DirectoryMetadata>
34# <FileSet>
35# <FileName>nugget.*</FileName>
36# <Description>
37# <Metadata name="Title">Nugget Point, The Catlins</Metadata>
38# <Metadata name="Place" mode="accumulate">Nugget Point</Metadata>
39# </Description>
40# </FileSet>
41# <FileSet>
42# <FileName>nugget-point-1.jpg</FileName>
43# <Description>
44# <Metadata name="Title">Nugget Point Lighthouse, The Catlins</Metadata>
45# <Metadata name="Subject">Lighthouse</Metadata>
46# </Description>
47# </FileSet>
48# <FileSet>
49# <FileName>kaka-point-dir</FileName>
50# <Description>
51# <Metadata name="Title">Kaka Point, The Catlins</Metadata>
52# </Description>
53# </FileSet>
54#</DirectoryMetadata>
55
56# Metadata elements are read and applied to files in the order they appear
57# in the file.
58#
59# The FileName element describes the subfiles in the directory that the
60# metadata applies to as a perl regular expression (a FileSet group may
61# contain multiple FileName elements). So, <FileName>nugget.*</FileName>
62# indicates that the metadata records in the following Description block
63# apply to every subfile that starts with "nugget". For these files, a
64# Title metadata element is set, overriding any old value that the Title
65# might have had.
66#
67# Occasionally, we want to have multiple metadata values applied to a
68# document; in this case we use the "mode=accumulate" attribute of the
69# particular Metadata element. In the second metadata element of the first
70# FileSet above, the "Place" metadata is accumulating, and may therefore be
71# given several values. If we wanted to override these values and use a
72# single metadata element again, we could set the mode attribute to
73# "override" instead. Remember: every element is assumed to be in override
74# mode unless you specify otherwise, so if you want to accumulate metadata
75# for some field, every occurance must have "mode=accumulate" specified.
76#
77# The second FileSet element above applies to a specific file, called
78# nugget-point-1.jpg. This element overrides the Title metadata set in the
79# first FileSet, and adds a "Subject" metadata field.
80#
81# The third and final FileSet sets metadata for a subdirectory rather than
82# a file. The metadata specified (a Title) will be passed into the
83# subdirectory and applied to every file that occurs in the subdirectory
84# (and to every subsubdirectory and its contents, and so on) unless the
85# metadata is explictly overridden later in the import.
86
87package MetadataXMLPlugin;
88
89use strict;
90no strict 'refs';
91
92use Encode;
93
94use BasePlugin;
95use extrametautil;
96use util;
97use FileUtils;
98use metadatautil;
99
100sub BEGIN {
101 @MetadataXMLPlugin::ISA = ('BasePlugin');
102 unshift (@INC, "$ENV{'GSDLHOME'}/perllib/cpan");
103}
104
105use XMLParser;
106
107my $arguments = [
108 { 'name' => "process_exp",
109 'desc' => "{BasePlugin.process_exp}",
110 'type' => "regexp",
111 'reqd' => "no",
112 'deft' => &get_default_process_exp() }
113
114];
115
116my $options = { 'name' => "MetadataXMLPlugin",
117 'desc' => "{MetadataXMLPlugin.desc}",
118 'abstract' => "no",
119 'inherits' => "yes",
120 'args' => $arguments };
121
122sub new {
123 my ($class) = shift (@_);
124 my ($pluginlist,$inputargs,$hashArgOptLists) = @_;
125 push(@$pluginlist, $class);
126
127 push(@{$hashArgOptLists->{"ArgList"}},@{$arguments});
128 push(@{$hashArgOptLists->{"OptList"}},$options);
129
130 my $self = new BasePlugin($pluginlist, $inputargs, $hashArgOptLists);
131
132 if ($self->{'info_only'}) {
133 # don't worry about any options or initialisations etc
134 return bless $self, $class;
135 }
136
137 # The following used to be passed in as a parameter to XML::Parser,
138 # if the version of perl was greater than or equal to 5.8.
139 # The svn commit comment explaining the reason for adding this was
140 # not very clear and also said that it was quick fix and hadn't
141 # been tested under windows.
142 # More recent work has been to make strings in Perl "Unicode-aware"
143 # and so this line might actually be potentially harmful, however
144 # it is not the case that we encountered an actual error leading to
145 # its removal, rather it has been eliminated in an attempt to tighten
146 # up the code. For example, this protocol encoding is not used in
147 # ReadXMLFile.
148 # 'ProtocolEncoding' => 'ISO-8859-1',
149
150 # create XML::Parser object for parsing metadata.xml files
151 my $parser = new XML::Parser('Style' => 'Stream',
152 'Pkg' => 'MetadataXMLPlugin',
153 'PluginObj' => $self,
154 'Handlers' => {'Char' => \&Char,
155 'Doctype' => \&Doctype
156 });
157
158 $self->{'parser'} = $parser;
159 $self->{'in_filename'} = 0;
160
161 return bless $self, $class;
162}
163
164
165sub get_default_process_exp
166{
167 return q^metadata\.xml$^;
168}
169
170sub get_doctype {
171 my $self = shift(@_);
172
173 return "(Greenstone)?DirectoryMetadata"
174}
175
176sub can_process_this_file {
177 my $self = shift(@_);
178 my ($filename) = @_;
179
180 if (-f $filename && $self->SUPER::can_process_this_file($filename) && $self->check_doctype($filename)) {
181 return 1; # its a file for us
182 }
183 return 0;
184}
185
186sub check_doctype {
187 my $self = shift (@_);
188
189 my ($filename) = @_;
190
191 if (open(XMLIN,"<$filename")) {
192 my $doctype = $self->get_doctype();
193 ## check whether the doctype has the same name as the root element tag
194 while (defined (my $line = <XMLIN>)) {
195 ## find the root element
196 if ($line =~ /<([\w\d:]+)[\s>]/){
197 my $root = $1;
198 if ($root !~ $doctype){
199 close(XMLIN);
200 return 0;
201 }
202 else {
203 close(XMLIN);
204 return 1;
205 }
206 }
207 }
208 close(XMLIN);
209 }
210
211 return undef; # haven't found a valid line
212
213}
214
215sub file_block_read {
216 my $self = shift (@_);
217 my ($pluginfo, $base_dir, $file, $block_hash, $metadata, $gli) = @_;
218
219 my $filename_full_path = &FileUtils::filenameConcatenate($base_dir, $file);
220 return undef unless $self->can_process_this_file($filename_full_path);
221
222 if (($ENV{'GSDLOS'} =~ m/^windows$/) && ($^O ne "cygwin")) {
223
224 my $lower_drive = $filename_full_path;
225 $lower_drive =~ s/^([A-Z]):/\l$1:/i;
226
227 my $upper_drive = $filename_full_path;
228 $upper_drive =~ s/^([A-Z]):/\u$1:/i;
229
230 $block_hash->{'metadata_files'}->{$lower_drive} = 1;
231 $block_hash->{'metadata_files'}->{$upper_drive} = 1;
232 }
233 else {
234 $block_hash->{'metadata_files'}->{$filename_full_path} = 1;
235 }
236
237 return 1;
238}
239
240sub metadata_read
241{
242 my $self = shift (@_);
243 my ($pluginfo, $base_dir, $file, $block_hash,
244 $extrametakeys, $extrametadata,$extrametafile,
245 $processor, $gli, $aux) = @_;
246
247 my $filename = &FileUtils::filenameConcatenate($base_dir, $file);
248 return undef unless $self->can_process_this_file($filename);
249
250 $self->{'metadata-file'} = $file;
251 $self->{'metadata-filename'} = $filename;
252
253 my $outhandle = $self->{'outhandle'};
254
255 print STDERR "\n<Processing n='$file' p='MetadataXMLPlugin'>\n" if ($gli);
256 print $outhandle "MetadataXMLPlugin: processing $file\n" if ($self->{'verbosity'})> 1;
257 # add the file to the block list so that it won't be processed in read, as we will do all we can with it here
258 &util::block_filename($block_hash,$filename);
259
260 $self->{'metadataref'} = $extrametadata;
261 $self->{'metafileref'} = $extrametafile;
262 $self->{'metakeysref'} = $extrametakeys;
263
264 eval {
265 $self->{'parser'}->parsefile($filename);
266 };
267
268 if ($@) {
269 print STDERR "**** Error is: $@\n";
270 my $plugin_name = ref ($self);
271 my $failhandle = $self->{'failhandle'};
272 print $outhandle "$plugin_name failed to process $file ($@)\n";
273 print $failhandle "$plugin_name failed to process $file ($@)\n";
274 print STDERR "<ProcessingError n='$file'>\n" if ($gli);
275 return -1; #error
276 }
277
278 return 1;
279
280}
281
282
283# Updated by Jeffrey 2010/04/16 @ DL Consulting Ltd.
284# Get rid off the global $self as it cause problems when there are 2+ MetadataXMLPlugin in your collect.cfg...
285# For example when you have an OAIMetadataXMLPlugin that is a child of MetadataXMLPlugin
286sub Doctype {$_[0]->{'PluginObj'}->xml_doctype(@_);}
287sub StartTag {$_[0]->{'PluginObj'}->xml_start_tag(@_);}
288sub EndTag {$_[0]->{'PluginObj'}->xml_end_tag(@_);}
289sub Text {$_[0]->{'PluginObj'}->xml_text(@_);}
290
291
292sub xml_doctype {
293 my $self = shift(@_);
294 my ($expat, $name, $sysid, $pubid, $internal) = @_;
295
296 # allow the short-lived and badly named "GreenstoneDirectoryMetadata" files
297 # to be processed as well as the "DirectoryMetadata" files which should now
298 # be created by import.pl
299 die if ($name !~ /^(Greenstone)?DirectoryMetadata$/);
300}
301
302sub xml_start_tag {
303 my $self = shift(@_);
304 my ($expat, $element) = @_;
305
306 if ($element eq "FileSet") {
307 $self->{'saved_targets'} = [];
308 $self->{'saved_metadata'} = {};
309 }
310 elsif ($element eq "FileName") {
311 $self->{'in_filename'} = 1;
312 }
313 elsif ($element eq "Metadata") {
314 $self->{'metadata_name'} = $_{'name'};
315 $self->{'metadata_value'} = "";
316 if ((defined $_{'mode'}) && ($_{'mode'} eq "accumulate")) {
317 $self->{'metadata_accumulate'} = 1;
318 } else {
319 $self->{'metadata_accumulate'} = 0;
320 }
321 }
322}
323
324sub xml_end_tag {
325 my $self = shift(@_);
326 my ($expat, $element) = @_;
327
328 if ($element eq "FileSet") {
329 foreach my $target (@{$self->{'saved_targets'}}) {
330
331 # FileNames must be regex, but we allow \\ for path separator on windows. convert to /
332 $target = &util::filepath_regex_to_url_format($target);
333 my $file_metadata = &extrametautil::getmetadata($self->{'metadataref'}, $target);
334 my $saved_metadata = $self->{'saved_metadata'};
335
336 if (!defined $file_metadata) {
337 &extrametautil::setmetadata($self->{'metadataref'}, $target, $saved_metadata);
338
339 # not had target before
340 &extrametautil::addmetakey($self->{'metakeysref'}, $target);
341 }
342 else {
343 &metadatautil::combine_metadata_structures($file_metadata,$saved_metadata);
344 }
345
346
347 # now record which metadata.xml file it came from
348
349 my $file = $self->{'metadata-file'};
350 my $filename = $self->{'metadata-filename'};
351
352 if (!defined &extrametautil::getmetafile($self->{'metafileref'}, $target)) {
353 &extrametautil::setmetafile($self->{'metafileref'}, $target, {});
354 }
355
356 &extrametautil::setmetafile_for_named_file($self->{'metafileref'}, $target, $file, $filename);
357 }
358 }
359 elsif ($element eq "FileName") {
360 $self->{'in_filename'} = 0;
361 }
362 elsif ($element eq "Metadata") {
363 # text read in by XML::Parser is in Perl's binary byte value
364 # form ... need to explicitly make it UTF-8
365
366 my $metadata_name = $self->{'metadata_name'};
367 my $metadata_value = $self->{'metadata_value'};
368 #my $metadata_name = decode("utf-8",$self->{'metadata_name'});
369 #my $metadata_value = decode("utf-8",$self->{'metadata_value'});
370
371 &metadatautil::store_saved_metadata($self,
372 $metadata_name, $metadata_value,
373 $self->{'metadata_accumulate'});
374 $self->{'metadata_name'} = "";
375 }
376
377}
378
379sub xml_text {
380 my $self = shift(@_);
381
382 if ($self->{'in_filename'}) {
383 # $_ == FileName content
384 push (@{$self->{'saved_targets'}}, $_);
385 }
386 elsif (defined ($self->{'metadata_name'}) && $self->{'metadata_name'} ne "") {
387 # $_ == Metadata content
388 $self->{'metadata_value'} = $_;
389 }
390}
391
392# This Char function overrides the one in XML::Parser::Stream to overcome a
393# problem where $expat->{Text} is treated as the return value, slowing
394# things down significantly in some cases.
395sub Char {
396# use bytes; # Necessary to prevent encoding issues with XML::Parser 2.31+
397
398# if ($]<5.008) {
399# use bytes; # Necessary to prevent encoding issues with XML::Parser 2.31+ and Perl 5.6
400# }
401 $_[0]->{'Text'} .= $_[1];
402 return undef;
403}
404
405
406
4071;
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