root/gsdl/trunk/perllib/plugins/OAIPlug.pm @ 14949

Revision 14949, 12.1 KB (checked in by davidb, 12 years ago)

Tweak to parsing of OAI metadata to XML tags within a metadata field don't trip it up

  • Property svn:keywords set to Author Date Id Revision
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1###########################################################################
2#
3# OAIPlug.pm -- basic Open Archives Initiative (OAI) plugin
4#
5# A component of the Greenstone digital library software
6# from the New Zealand Digital Library Project at the
7# University of Waikato, New Zealand.
8#
9# Copyright (C) 1999 New Zealand Digital Library Project
10#
11# This program is free software; you can redistribute it and/or modify
12# it under the terms of the GNU General Public License as published by
13# the Free Software Foundation; either version 2 of the License, or
14# (at your option) any later version.
15#
16# This program is distributed in the hope that it will be useful,
17# but WITHOUT ANY WARRANTY; without even the implied warranty of
18# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19# GNU General Public License for more details.
20#
21# You should have received a copy of the GNU General Public License
22# along with this program; if not, write to the Free Software
23# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24#
25###########################################################################
26
27package OAIPlug;
28
29use BasPlug;
30use unicode;
31use util;
32
33use strict;
34no strict 'refs'; # allow filehandles to be variables and viceversa
35
36use XMLPlug;
37
38sub BEGIN {
39    @OAIPlug::ISA = ('XMLPlug');
40}
41
42
43my $arguments =
44    [ { 'name' => "process_exp",
45    'desc' => "{BasPlug.process_exp}",
46    'type' => "regexp",
47    'reqd' => "no",
48    'deft' => &get_default_process_exp() },
49      ];
50
51my $options = { 'name'     => "OAIPlug",
52        'desc'     => "{OAIPlug.desc}",
53        'abstract' => "no",
54        'inherits' => "yes",
55        'args'     => $arguments };
56
57
58sub new {
59    my ($class) = shift (@_);
60    my ($pluginlist,$inputargs,$hashArgOptLists) = @_;
61    push(@$pluginlist, $class);
62
63    if(defined $arguments){ push(@{$hashArgOptLists->{"ArgList"}},@{$arguments});}
64    if(defined $options) { push(@{$hashArgOptLists->{"OptList"}},$options)};
65
66    my $self = new XMLPlug($pluginlist, $inputargs, $hashArgOptLists);
67
68    return bless $self, $class;
69}
70
71sub get_default_process_exp {
72    my $self = shift (@_);
73
74    return q^(?i)(\.oai)$^;
75}
76
77sub get_doctype {
78    my $self = shift(@_);
79   
80    return "OAI-PMH";
81}
82
83sub xml_start_document {
84    my $self = shift (@_);
85    $self->{'in_metadata_node'} = 0;
86    $self->{'rawxml'} = "";
87}
88
89sub xml_end_document {
90}
91
92sub xml_doctype {
93    my $self = shift(@_);
94
95    my ($expat, $name, $sysid, $pubid, $internal) = @_;
96
97    ##die "" if ($name !~ /^OAI-PMH$/);
98
99    my $outhandle = $self->{'outhandle'};
100    print $outhandle "OAIPlug: processing $self->{'file'}\n" if $self->{'verbosity'} > 1;
101    print STDERR "<Processing n='$self->{'file'}' p='OAIPlug'>\n" if $self->{'gli'};
102
103}
104
105
106sub xml_start_tag {
107    my $self = shift(@_);
108    my ($expat,$element) = @_;
109
110    my %attr_hash = %_;
111
112    my $attr = "";
113    map { $attr .= " $_=$attr_hash{$_}"; } keys %attr_hash;
114
115    $self->{'rawxml'} .= "<$element$attr>";
116
117    if ($element eq "metadata") {
118    $self->{'in_metadata_node'} = 1;
119    $self->{'metadata_xml'} = "";
120    }
121
122    if ($self->{'in_metadata_node'}) {
123    $self->{'metadata_xml'} .= "<$element$attr>";
124    }
125}
126
127sub xml_end_tag {
128    my $self = shift(@_);
129    my ($expat, $element) = @_;
130
131    $self->{'rawxml'} .= "</$element>";
132
133    if ($self->{'in_metadata_node'}) {
134    $self->{'metadata_xml'} .= "</$element>";
135    }
136
137    if ($element eq "metadata") {
138    my $textref = \$self->{'metadata_xml'};
139    my $metadata = $self->{'metadata'};
140    $self->extract_oai_metadata($textref,$metadata);
141
142    $self->{'in_metadata_node'} = 0;   
143    }
144
145
146}
147
148sub xml_text {
149    my $self = shift(@_);
150    my ($expat) = @_;
151
152    $self->{'rawxml'} .= $_;
153
154    if ($self->{'in_metadata_node'}) {
155    $self->{'metadata_xml'} .= $_;
156    }
157}
158
159
160
161
162sub read {
163    my $self = shift (@_); 
164 
165    my ($pluginfo, $base_dir, $file, $metadata, $processor, $maxdocs, $total_count, $gli) = @_;
166
167    my $outhandle = $self->{'outhandle'};
168
169    my $filename = $file;
170    $filename = &util::filename_cat ($base_dir, $file) if $base_dir =~ /\w/;
171
172    return 0 if ((-d $filename) && ($filename =~ m/srcdocs$/));
173
174    if ($self->SUPER::read(@_)) {
175
176    # Do encoding stuff
177    my ($language, $encoding) = $self->textcat_get_language_encoding ($filename);
178   
179    my $url_array = $metadata->{'URL'};
180    my $num_urls = (defined $url_array) ? scalar(@$url_array) : 0;
181   
182    my $srcdoc_exists = 0;
183    my $srcdoc_pos = 0;
184    my $filename_dir = &util::filename_head($filename);
185   
186    for (my $i=0; $i<$num_urls; $i++) {
187       
188        if ($url_array->[$i] !~ m/^(http|ftp):/) {
189       
190        my $src_filename = &util::filename_cat($filename_dir, $url_array->[$i]);
191       
192        if (-e $src_filename) {
193            $srcdoc_pos = $i;
194            $srcdoc_exists = 1;
195        }
196        }
197    }
198   
199    if ($srcdoc_exists)
200    {
201        print $outhandle "OAIPlug: passing metadata on to $url_array->[0]\n"
202        if ($self->{'verbosity'}>1);
203       
204       
205        # Make pretty print metadata table stick with src filename
206        my $ppmd_table = $self->{'ppmd_table'};
207        $metadata->{'prettymd'} = [ $ppmd_table ];
208        $self->{'ppmd_table'} = undef;
209       
210        return &plugin::read ($pluginfo, $filename_dir, $url_array->[0],
211                  $metadata, $processor, $maxdocs, $total_count, $gli);
212    }
213    else
214    {
215        # create a new document
216        my $doc_obj = new doc ($filename, "indexed_doc");
217        my $top_section = $doc_obj->get_top_section;
218        my $plugin_type = $self->{'plugin_type'};
219       
220        $doc_obj->add_utf8_metadata($top_section, "Language", $language);
221        $doc_obj->add_utf8_metadata($top_section, "Encoding", $encoding);
222        $doc_obj->add_utf8_metadata($top_section, "Plugin", $plugin_type);
223        $doc_obj->add_metadata($top_section, "FileFormat", "OAI");
224        $doc_obj->add_metadata($top_section, "FileSize", (-s $filename));
225       
226        # include any metadata passed in from previous plugins
227        # note that this metadata is associated with the top level section
228        $self->extra_metadata ($doc_obj, $doc_obj->get_top_section(), $metadata);
229       
230        # do plugin specific processing of doc_obj
231        my $textref = \$self->{'rawxml'};
232        unless (defined ($self->process($textref, $pluginfo, $base_dir, $file, $metadata, $doc_obj))) {
233        print STDERR "<ProcessingError n='$file'>\n" if ($gli);
234        return -1;
235        }
236       
237        # do any automatic metadata extraction
238        $self->auto_extract_metadata ($doc_obj);
239       
240        # add an OID
241        $doc_obj->set_OID();
242       
243        my $ppmd_table = $self->{'ppmd_table'};
244        $doc_obj->add_utf8_metadata($top_section,"prettymd",$ppmd_table);
245        $self->{'ppmd_table'} = undef;
246       
247        # process the document
248        $processor->process($doc_obj);
249       
250        $self->{'num_processed'} ++;
251       
252        return 1; # processed the file
253    }
254    }
255    else {
256    return undef;
257    }
258}
259
260
261# do plugin specific processing of doc_obj
262sub process {
263    my $self = shift (@_);
264    my ($textref, $pluginfo, $base_dir, $file, $metadata, $doc_obj, $gli) = @_;
265    my $outhandle = $self->{'outhandle'};
266
267    print STDERR "<Processing n='$file' p='OAIPlug'>\n" if ($gli);
268    print $outhandle "OAIPlug: processing $file\n"
269    if $self->{'verbosity'} > 1;
270
271    my $cursection = $doc_obj->get_top_section();
272
273##    $self->extract_metadata ($textref, $metadata, $doc_obj, $cursection);
274
275    # add text to document object
276
277#    $$textref =~ s/<(.*?)>/$1 /g;
278    $$textref =~ s/</&lt;/g;
279    $$textref =~ s/>/&gt;/g;
280
281##    print STDERR "*** adding text: $$textref\n";
282   
283    $doc_obj->add_utf8_text($cursection, $$textref);
284
285    return 1;
286}
287
288
289# Improvement is to merge this with newer version in MetadataPass
290
291sub open_prettyprint_metadata_table
292{
293    my $self = shift(@_);
294
295    my $att   = "width=100% cellspacing=2";
296    my $style = "style=\'border-bottom: 4px solid #000080\'";
297
298    $self->{'ppmd_table'} = "\n<table $att $style>";
299}
300
301sub add_prettyprint_metadata_line
302{
303    my $self = shift(@_);
304    my ($metaname, $metavalue_utf8) = @_;
305
306###    $metavalue_utf8 =~ s/hdl\.handle\.net/mcgonagall.cs.waikato.ac.nz:8080\/dspace\/handle/;
307    $metavalue_utf8 = &util::hyperlink_text($metavalue_utf8);
308
309    $self->{'ppmd_table'} .= "  <tr bgcolor=#b5d3cd>\n";
310    $self->{'ppmd_table'} .= "    <td width=30%>\n";
311    $self->{'ppmd_table'} .= "      $metaname\n";
312    $self->{'ppmd_table'} .= "    </td>\n";
313    $self->{'ppmd_table'} .= "    <td>\n";
314    $self->{'ppmd_table'} .= "      $metavalue_utf8\n";
315    $self->{'ppmd_table'} .= "    </td>\n";
316    $self->{'ppmd_table'} .= "  </tr>\n";
317
318}
319
320sub close_prettyprint_metadata_table
321{
322    my $self = shift(@_);
323
324    $self->{'ppmd_table'} .= "</table>\n";
325}
326
327
328sub remap_dcterms_metadata
329{
330    my $self = shift(@_);
331
332    my ($metaname) = @_;
333
334    my $dcterm_mapping = {
335    "alternative" => "dc.title",
336    "tableOfContents" => "dc.description",
337    "abstract" => "dc.description",
338    "created" => "dc.date",
339    "valid" => "dc.date",
340    "available" => "dc.date",
341    "issued" => "dc.date",
342    "modified" => "dc.date",
343    "dateAccepted" => "dc.date",
344    "dateCopyrighted" => "dc.date",
345    "dateSubmitted" => "dc.date",
346    "extent" => "dc.format",
347    "medium" => "dc.format",
348    "isVersionOf" => "dc.relation",
349    "hasVersion" => "dc.relation",
350    "isReplacedBy" => "dc.relation",
351    "replaces" => "dc.relation",
352    "isRequiredBy" => "dc.relation",
353    "requires" => "dc.relation",
354    "isPartOf" => "dc.relation",
355    "hasPart" => "dc.relation",
356    "isReferencedBy" => "dc.relation",
357    "references" => "dc.relation",
358    "isFormatOf" => "dc.relation",
359    "hasFormat" => "dc.relation",
360    "conformsTo" => "dc.relation",
361    "spatial" => "dc.coverage",
362    "temporal" => "dc.coverage",
363    "audience" => "dc.any",
364    "accrualMethod" => "dc.any",
365    "accrualPeriodicity" => "dc.any",
366    "accrualPolicy" => "dc.any",
367    "instructionalMethod" => "dc.any",
368    "provenance" => "dc.any",
369    "rightsHolder" => "dc.any",
370    "mediator" => "audience",
371    "educationLevel" => "audience",
372    "accessRights" => "dc.rights",
373    "license" => "dc.rights",
374    "bibliographicCitation" => "dc.identifier"
375    };
376
377    my ($prefix,$name) = ($metaname =~ m/^(.*?)\.(.*?)$/);
378   
379    if ($prefix eq "dcterms")
380    {
381    if (defined $dcterm_mapping->{$name})
382    {
383        return $dcterm_mapping->{$name}."^".$name;
384    }
385
386    }
387    return $metaname; # didn't get a match, return param passed in unchanged
388}
389
390
391sub extract_oai_metadata {
392    my $self = shift (@_);
393    my ($textref, $metadata) = @_;
394    my $outhandle = $self->{'outhandle'};
395
396    # Only handles DC metadata
397
398    $self->open_prettyprint_metadata_table();
399
400    if ($$textref =~ m/<metadata\s*>(.*?)<\/metadata\s*>/s)
401    {
402    my $metadata_text = $1;
403
404    # locate and remove outermost tag (ignoring any attribute information in top-level tag)
405    my ($wrapper_metadata_xml,$inner_metadata_text) = ($metadata_text =~ m/<([^ >]+).*?>(.*?)<\/\1>/s);
406
407    # split tag into namespace and tag name
408    my($namespace,$top_level_prefix) = ($wrapper_metadata_xml =~ m/^(.*?):(.*?)$/);
409
410    if ($top_level_prefix !~ /dc$/) {
411        print $outhandle "Warning: OAIPlug currently only designed for Dublin Core (or variant) metadata\n";
412        print $outhandle "         This recorded metadata section '$top_level_prefix' does not appear to match.\n";
413        print $outhandle "         Metadata assumed to be in form: <prefix:tag>value</prefix:tag> and will be converted\n";
414        print $outhandle "         into Greenstone metadata as prefix.tag = value\n";
415    }
416
417    while ($inner_metadata_text =~ m/<([^ >]+).*?>(.*?)<\/\1>(.*)/s)
418    {
419        # if URL given for document as identifier metadata, store it ...
420        # $doc_obj->add_utf8_metadata($cursection, "URL", $web_url);
421
422        my $metaname = $1;
423        my $metavalue = $2;
424        $inner_metadata_text = $3;
425
426#       print STDERR "*** metaname = $metaname\n";
427#       print STDERR "*** metavalue = $metavalue\n";
428
429        # $metaname =~ s/^(dc:)?(.)/\u$2/; # strip of optional prefix and uppercase first letter
430        $metaname =~ s/:/\./;
431        if ($metaname !~ m/\./)
432        {
433        $metaname = "$top_level_prefix.$metaname";
434        }
435
436
437        $metaname = $self->remap_dcterms_metadata($metaname);
438
439#       if ($metaname eq "Identifier")
440#       {
441#       # name clashes with GSDL reserved metadata name for hash id
442#       $metaname = "URL";
443#       }
444
445        if (defined $metadata->{$metaname})
446        {
447        push(@{$metadata->{$metaname}},$metavalue);
448
449        }
450        else
451        {
452        $metadata->{$metaname} = [ $metavalue ];
453        }
454
455        $self->add_prettyprint_metadata_line($metaname, $metavalue);
456       
457    }
458    }
459
460    $self->close_prettyprint_metadata_table();
461}
462
463## we know from the file extension, so doesn't need to check the doctype
464sub check_doctype {
465
466    return 1;
467}
468
4691;
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