source: main/trunk/greenstone3/src/java/org/greenstone/gsdl3/service/OAIPMH.java@ 30555

Last change on this file since 30555 was 30555, checked in by kjdon, 8 years ago

undoing last commit which was made by mistake
File size: 30.2 KB
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1/*
2 * OAIPMH.java
3 * Copyright (C) 2010 New Zealand Digital Library, http://www.nzdl.org
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19package org.greenstone.gsdl3.service;
20
21// Greenstone classes
22import org.greenstone.gsdl3.core.GSException;
23import org.greenstone.gsdl3.util.GSXML;
24import org.greenstone.gsdl3.util.OAIXML;
25import org.greenstone.gsdl3.util.OID;
26import org.greenstone.gsdl3.util.GSFile;
27import org.greenstone.gsdl3.util.XMLConverter;
28
29import org.greenstone.gsdl3.util.SimpleCollectionDatabase;
30import org.greenstone.gsdl3.util.DBInfo;
31// XML classes
32import org.w3c.dom.Document;
33import org.w3c.dom.Element;
34import org.w3c.dom.NodeList;
35
36// General Java classes
37import java.io.File;
38import java.util.StringTokenizer;
39import java.util.Vector;
40import java.util.Set;
41import java.util.Iterator;
42import java.util.ArrayList;
43import java.util.Date;
44import java.util.HashMap;
45import java.util.HashSet;
46import java.util.Map.Entry;
47
48import org.apache.log4j.Logger;
49
50/** Implements the oai metadata retrieval service for GS3 collections.
51 * Dig into each collection's database and retrieve the metadata
52 *
53 */
54
55public class OAIPMH extends ServiceRack {
56
57 static Logger logger = Logger.getLogger(org.greenstone.gsdl3.service.OAIPMH.class.getName());
58
59 protected SimpleCollectionDatabase coll_db = null;
60
61 protected String site_name = "";
62 protected String coll_name = "";
63
64 // set this up during configure
65 protected Element list_sets_response = null;
66
67 protected Element meta_formats_definition = null;
68 protected HashMap<String, HashSet<String>> format_elements_map = null;
69 protected HashMap<String, Element> format_response_map = null;
70 /** constructor */
71 public OAIPMH() {
72
73 }
74
75 public void cleanUp() {
76 super.cleanUp();//??
77 this.coll_db.closeDatabase();
78 }
79 /** configure this service
80 info is the OAIPMH service rack from collectionConfig.xml, and
81 extra_info is buildConfig.xml */
82 public boolean configure(Element info, Element extra_info) {
83 if (!super.configure(info, extra_info)){
84 logger.info("Configuring ServiceRack.java returns false.");
85 return false;
86 }
87
88 //get the names from ServiceRack.java
89 this.site_name = this.router.getSiteName();
90 this.coll_name = this.cluster_name;
91
92 logger.info("Configuring OAIPMH...");
93
94 this.config_info = info;
95
96 // the index stem is either specified in the buildConfig.xml file (extra_info) or uses the collection name
97 Element metadata_list = (Element) GSXML.getChildByTagName(extra_info, GSXML.METADATA_ELEM+GSXML.LIST_MODIFIER);
98 String index_stem = "";
99 String infodb_type = "";
100 if (metadata_list != null) {
101
102 Element index_stem_elem = (Element) GSXML.getNamedElement(metadata_list, GSXML.METADATA_ELEM, GSXML.NAME_ATT, "indexStem");
103
104 if (index_stem_elem != null) {
105 index_stem = GSXML.getNodeText(index_stem_elem);
106 }
107
108 Element infodb_type_elem = (Element) GSXML.getNamedElement(metadata_list, GSXML.METADATA_ELEM, GSXML.NAME_ATT, "infodbType");
109 if (infodb_type_elem != null) {
110 infodb_type = GSXML.getNodeText(infodb_type_elem);
111 }
112
113 }
114
115 if (index_stem == null || index_stem.equals("")) {
116 index_stem = this.cluster_name;
117 }
118 if (infodb_type == null || infodb_type.equals("")) {
119 infodb_type = "gdbm"; // the default
120 }
121
122 coll_db = new SimpleCollectionDatabase(infodb_type);
123 if (!coll_db.databaseOK()) {
124 logger.error("Couldn't create the collection database of type "+infodb_type);
125 return false;
126 }
127
128 // Open database for querying
129 String coll_db_file = GSFile.collectionDatabaseFile(this.site_home, this.cluster_name, index_stem, infodb_type);
130 if (!this.coll_db.openDatabase(coll_db_file, SimpleCollectionDatabase.READ)) {
131 logger.error("Could not open collection database!");
132 return false;
133 }
134
135 // work out what sets this collection has. Will usually contain the collection itself, optional super collection, and maybe subcolls if appropriate classifiers are present.
136 configureSetInfo();
137 // the short_service_info is used by the message router to find the method names,
138
139 Element list_records = this.desc_doc.createElement(GSXML.SERVICE_ELEM);
140 list_records.setAttribute(GSXML.NAME_ATT, OAIXML.LIST_RECORDS);
141 list_records.setAttribute(GSXML.TYPE_ATT, "oai");
142 this.short_service_info.appendChild(list_records);
143
144 Element list_identifiers = this.desc_doc.createElement(GSXML.SERVICE_ELEM);
145 list_identifiers.setAttribute(GSXML.NAME_ATT, OAIXML.LIST_IDENTIFIERS);
146 list_identifiers.setAttribute(GSXML.TYPE_ATT, "oai");
147 this.short_service_info.appendChild(list_identifiers);
148
149 Element list_sets = this.desc_doc.createElement(GSXML.SERVICE_ELEM);
150 list_sets.setAttribute(GSXML.NAME_ATT, OAIXML.LIST_SETS);
151 list_sets.setAttribute(GSXML.TYPE_ATT, "oai");
152 this.short_service_info.appendChild(list_sets);
153
154 Element list_metadata_formats = this.desc_doc.createElement(GSXML.SERVICE_ELEM);
155 list_metadata_formats.setAttribute(GSXML.NAME_ATT, OAIXML.LIST_METADATA_FORMATS);
156 list_metadata_formats.setAttribute(GSXML.TYPE_ATT, "oai");
157 this.short_service_info.appendChild(list_metadata_formats);
158
159 Element get_record = this.desc_doc.createElement(GSXML.SERVICE_ELEM);
160 get_record.setAttribute(GSXML.NAME_ATT, OAIXML.GET_RECORD);
161 get_record.setAttribute(GSXML.TYPE_ATT, "oai");
162 this.short_service_info.appendChild(get_record);
163
164 return true;
165 }
166
167 public boolean configureOAI(Element oai_config_elem) {
168 this.meta_formats_definition = this.desc_doc.createElement(OAIXML.LIST_METADATA_FORMATS);
169 this.format_response_map = new HashMap<String, Element>();
170 this.format_elements_map = new HashMap<String, HashSet<String>>();
171
172 // for now, all we want is the metadata prefix description and the mapping list
173 Element main_lmf_elem = (Element) GSXML.getChildByTagName(oai_config_elem, OAIXML.LIST_METADATA_FORMATS);
174 if (main_lmf_elem == null) {
175 logger.error("No listMetadataFormats element found in OAIConfig.xml");
176 return false;
177 }
178 NodeList meta_formats_list = this.config_info.getElementsByTagName(OAIXML.METADATA_FORMAT);
179 if (meta_formats_list.getLength() == 0) {
180 logger.error("no metadataFormat elements found in OAIPMH serviceRack element");
181 return false;
182 }
183 boolean found_meta_format = false;
184 for(int i=0; i<meta_formats_list.getLength(); i++) {
185 Element mf = (Element) meta_formats_list.item(i);
186 String prefix = mf.getAttribute(OAIXML.METADATA_PREFIX);
187 if (prefix.equals("")) {
188 logger.error("metadataFormat element had no metadataPrefix attribute");
189 continue;
190 }
191 // get the right format from OAICOnfig
192 Element meta_format = findNamedMetadataFormat(main_lmf_elem, prefix);
193 if (meta_format == null) {
194 logger.error("Couldn't find metadataFormat named "+prefix+" in OAIConfig.xml");
195 continue;
196 }
197 // copy the format definition into our stored Element
198 Element collection_version_format = (Element) this.desc_doc.importNode(meta_format, true);
199 collection_version_format.setAttribute(GSXML.NAME_ATT, prefix); // for convenience
200 this.meta_formats_definition.appendChild(collection_version_format);
201 // set up the response element for this format
202 format_response_map.put(prefix, OAIXML.getMetadataFormatShort(this.desc_doc, collection_version_format));
203 // add in collection specific mappings
204 addCollectionMappings(collection_version_format, mf);
205 // now set up a list of all collection elements for reverse lookup of the mapping
206 format_elements_map.put(prefix, getAllCollectionElements(collection_version_format));
207
208 }
209 return true;
210 }
211
212 protected Element findNamedMetadataFormat(Element list_meta_formats, String prefix) {
213 NodeList formats = list_meta_formats.getElementsByTagName(OAIXML.METADATA_FORMAT);
214 for (int i=0; i<formats.getLength(); i++) {
215 Element format = (Element)formats.item(i);
216 String meta_name = GSXML.getNodeText((Element)GSXML.getChildByTagName(format, OAIXML.METADATA_PREFIX));
217 if (prefix.equals(meta_name)) {
218 return format;
219 }
220 }
221 return null;
222 }
223
224 /** goes through the mappings from the collection one, and replaces existing ones in the main one */
225 protected void addCollectionMappings(Element main_meta_format, Element coll_meta_format) {
226
227 Element element_list = (Element)GSXML.getChildByTagName(main_meta_format, OAIXML.ELEMENT+GSXML.LIST_MODIFIER);
228 Document doc = element_list.getOwnerDocument();
229 NodeList coll_elements = coll_meta_format.getElementsByTagName(OAIXML.ELEMENT);
230 if (coll_elements.getLength()==0) {
231 // no mappings to include
232 return;
233 }
234 for (int i=0; i<coll_elements.getLength(); i++) {
235 Element e = (Element)coll_elements.item(i);
236 String elem_name = e.getAttribute(GSXML.NAME_ATT);
237 Element main_elem = GSXML.getNamedElement(element_list, OAIXML.ELEMENT, GSXML.NAME_ATT, elem_name);
238 if (main_elem == null) {
239 logger.error(elem_name+" not found in meta format, not using it");
240 } else {
241 element_list.replaceChild(doc.importNode(e, true),main_elem );
242 }
243 }
244 }
245
246 /** goes through all the mappings and makes a set of all collection
247 metadata names that could become an oai meta element - acts as
248 a reverse lookup for the mappings */
249 protected HashSet<String> getAllCollectionElements(Element meta_format) {
250 HashSet<String> meta_name_set = new HashSet<String>();
251 NodeList elements = meta_format.getElementsByTagName(OAIXML.ELEMENT);
252 for (int i=0; i<elements.getLength(); i++) {
253 Element e = (Element)elements.item(i);
254 Element map = (Element)GSXML.getChildByTagName(e, OAIXML.MAPPING);
255 if (map == null) {
256 // there is no mapping, just use the element name
257 meta_name_set.add(e.getAttribute(GSXML.NAME_ATT));
258 } else {
259 String list_of_names = map.getAttribute(OAIXML.ELEMENTS);
260 String[] name_array = list_of_names.split(",");
261 for (int j=0; j<name_array.length; j++) {
262 meta_name_set.add(name_array[j]);
263 }
264 }
265 }
266 return meta_name_set;
267 }
268
269 /** returns a specific service description */
270 public Element getServiceDescription(Document doc, String service_id, String lang, String subset) {
271
272 if (service_id.equals(OAIXML.LIST_RECORDS)) {
273 Element list_records = doc.createElement(GSXML.SERVICE_ELEM);
274 list_records.setAttribute(GSXML.NAME_ATT, OAIXML.LIST_RECORDS);
275 list_records.setAttribute(GSXML.TYPE_ATT, "oai");
276 return list_records;
277 }
278
279 if (service_id.equals(OAIXML.LIST_IDENTIFIERS)) {
280 Element list_identifiers = doc.createElement(GSXML.SERVICE_ELEM);
281 list_identifiers.setAttribute(GSXML.NAME_ATT, OAIXML.LIST_IDENTIFIERS);
282 list_identifiers.setAttribute(GSXML.TYPE_ATT, "oai");
283 return list_identifiers;
284 }
285 if (service_id.equals(OAIXML.LIST_SETS)) {
286 Element list_sets = doc.createElement(GSXML.SERVICE_ELEM);
287 list_sets.setAttribute(GSXML.NAME_ATT, OAIXML.LIST_SETS);
288 list_sets.setAttribute(GSXML.TYPE_ATT, "oai");
289 return list_sets;
290 }
291 if (service_id.equals(OAIXML.LIST_METADATA_FORMATS)) {
292 Element list_metadata_formats = doc.createElement(GSXML.SERVICE_ELEM);
293 list_metadata_formats.setAttribute(GSXML.NAME_ATT, OAIXML.LIST_METADATA_FORMATS);
294 list_metadata_formats.setAttribute(GSXML.TYPE_ATT, "oai");
295 return list_metadata_formats;
296 }
297
298 if (service_id.equals(OAIXML.GET_RECORD)) {
299 Element get_record = doc.createElement(GSXML.SERVICE_ELEM);
300 get_record.setAttribute(GSXML.NAME_ATT, OAIXML.GET_RECORD);
301 get_record.setAttribute(GSXML.TYPE_ATT, "oai");
302 return get_record;
303 }
304
305 return null;
306 }
307
308 /** The list sets service returns all the sets that this collection is/is part of/contains. This is gathered by Receptionist from all collections to answer the OAI ListSets request. */
309 protected Element processListSets(Element req) {
310 return list_sets_response;
311 }
312 /** returns the actual record element used in the OAI GetRecord response */
313 protected Element processGetRecord(Element req) {
314 /** arguments:
315 identifier: required
316 metadataPrefix: required
317 * Exceptions: badArgument; cannotDisseminateFormat; idDoesNotExist
318 */
319 NodeList params = GSXML.getChildrenByTagName(req, GSXML.PARAM_ELEM);
320 HashMap<String, String> param_map = GSXML.getParamMap(params);
321
322 String prefix = param_map.get(OAIXML.METADATA_PREFIX);
323 if (prefix == null || prefix.equals("")) {
324 //Just a double-check
325 logger.error("the value of metadataPrefix att is not present in the request.");
326 return OAIXML.createErrorResponse(OAIXML.CANNOT_DISSEMINATE_FORMAT, "");
327 }
328
329 // check that we support this format
330 if (!format_response_map.containsKey(prefix)) {
331 logger.error("metadata prefix is not supported for collection "+this.coll_name);
332 return OAIXML.createErrorResponse(OAIXML.CANNOT_DISSEMINATE_FORMAT, "");
333 }
334
335 String oid = param_map.get(OAIXML.OID); // TODO should this be identifier???
336
337 //get a DBInfo object of the identifier; if this identifier is not present in the database,
338 // null is returned.
339 DBInfo info = this.coll_db.getInfo(oid);
340 if (info == null) {
341 logger.error("OID: " + oid + " is not present in the database.");
342 return OAIXML.createErrorResponse(OAIXML.ID_DOES_NOT_EXIST, "");
343 }
344
345 Document doc = XMLConverter.newDOM();
346 ArrayList<String> keys = new ArrayList<String>(info.getKeys());
347 long millis = getDateStampMillis(info);
348 String oailastmodified = "";
349 if (millis != -1) {
350 oailastmodified = OAIXML.getTime(millis);
351 }
352
353 Element get_record_response = doc.createElement(GSXML.RESPONSE_ELEM);
354 Element get_record = doc.createElement(OAIXML.GET_RECORD);
355 get_record_response.appendChild(get_record);
356 Element record = doc.createElement(OAIXML.RECORD);
357 //compose the header element
358 record.appendChild(createHeaderElement(doc, oid, oailastmodified));
359 //compose the metadata element
360 record.appendChild(createMetadataElement(doc, prefix, info));
361 get_record.appendChild(record);
362 return get_record_response;
363 }
364
365 /** return a list of records in specified set, containing metadata from specified prefix*/
366 protected Element processListRecords(Element req) {
367 return processListIdentifiersOrRecords(req, OAIXML.LIST_RECORDS, true);
368 }
369
370 /** return a list of identifiers in specified set that contain metadata belonging to specified prefix. */
371 protected Element processListIdentifiers(Element req) {
372 return processListIdentifiersOrRecords(req, OAIXML.LIST_IDENTIFIERS, false);
373 }
374
375 // Get a list of records/identifiers that match the parameters.
376 protected Element processListIdentifiersOrRecords(Element req, String response_name, boolean include_metadata) {
377 /** arguments:
378 metadataPrefix: required
379 * from: optional
380 * until: optional
381 * set: optional
382 * resumptionToken: exclusive and optional (ignored as it has been handled by OAIReceptionist)
383 * Exceptions: badArgument; cannotDisseminateFormat; idDoesNotExist
384 */
385 NodeList params = GSXML.getChildrenByTagName(req, GSXML.PARAM_ELEM);
386
387 if(params.getLength() == 0) {
388 logger.error("must at least have the metadataPrefix parameter, can't be none");
389 return OAIXML.createErrorResponse(OAIXML.BAD_ARGUMENT, "");
390 }
391
392 HashMap<String, String> param_map = GSXML.getParamMap(params);
393
394 String prefix = "";
395 Date from_date = null;
396 Date until_date = null;
397
398 if(param_map.containsKey(OAIXML.METADATA_PREFIX) == false) {
399 //Just a double-check
400 logger.error("A param element containing the metadataPrefix is not present.");
401 return OAIXML.createErrorResponse(OAIXML.CANNOT_DISSEMINATE_FORMAT, "");
402 }
403 prefix = param_map.get(OAIXML.METADATA_PREFIX);
404 if (prefix == null || prefix.equals("")) {
405 //Just a double-check
406 logger.error("the value of metadataPrefix att is not present in the request.");
407 return OAIXML.createErrorResponse(OAIXML.CANNOT_DISSEMINATE_FORMAT, "");
408 }
409
410 if(param_map.containsKey(OAIXML.FROM)) {
411 String from = param_map.get(OAIXML.FROM);
412 from_date = OAIXML.getDate(from);
413 }
414 if(param_map.containsKey(OAIXML.UNTIL)) {
415 String until = param_map.get(OAIXML.UNTIL);
416 until_date = OAIXML.getDate(until);
417 }
418
419 if (!format_response_map.containsKey(prefix)) {
420 logger.error(prefix + " metadata prefix is not supported for collection "+this.coll_name);
421 return OAIXML.createErrorResponse(OAIXML.CANNOT_DISSEMINATE_FORMAT, "");
422 }
423 ArrayList<String> oid_list = getChildrenIds(OAIXML.BROWSELIST);
424 if (oid_list == null) {
425 logger.error("No matched records found in collection: browselist is empty");
426 return OAIXML.createErrorResponse(OAIXML.NO_RECORDS_MATCH, "");
427 }
428 // all validation is done
429
430 // get the list of elements that are in this metadata prefix
431 HashSet<String> set_of_elems = format_elements_map.get(prefix);
432
433 Document doc = XMLConverter.newDOM();
434 Element list_items_response = doc.createElement(GSXML.RESPONSE_ELEM);
435 Element list_items = doc.createElement(response_name);
436 list_items_response.appendChild(list_items);
437
438 for(int i=0; i<oid_list.size(); i++) {
439 String oid = oid_list.get(i);
440 DBInfo info = this.coll_db.getInfo(oid);
441 if (info == null) {
442 logger.error("Database does not contains information about oid: " +oid);
443 continue;
444 }
445
446 long millis = getDateStampMillis(info);
447 Date this_date = null;
448 if (millis == -1) {
449 if (from_date != null || until_date !=null) {
450 continue; // if this doc doesn't have a date for some reason, and
451 // we are doing a date range, then don't include it.
452 }
453 } else {
454 this_date = new Date(millis);
455 if (from_date != null) {
456 if(this_date.before(from_date)) {
457 continue;
458 }
459 }
460 if (until_date != null) {
461 if (this_date.after(until_date)) {
462 continue;
463 }
464 }
465 }
466
467 //Now check that this id has metadata for the required prefix.
468 if (documentContainsMetadata(info, set_of_elems)) {
469 // YES, it does have some metadata for this prefix
470 if (include_metadata) {
471 // compose a record and add header and metadata
472 Element record = doc.createElement(OAIXML.RECORD);
473 list_items.appendChild(record);
474 //compose the header element
475 record.appendChild(createHeaderElement(doc, oid, OAIXML.getTime(millis)));
476 //compose the metadata element
477 record.appendChild(createMetadataElement(doc, prefix, info));
478 } else {
479 //compose the header element and append it
480 list_items.appendChild(createHeaderElement(doc, oid, OAIXML.getTime(millis)));
481 }
482 } // otherwise we won't include this oid.
483 }//end of for(int i=0; i<oid_list.size(); i++) of doing thru each record
484
485 return list_items_response;
486
487 }
488
489
490 // have implemented setDescription as an element, instead of a container containing metadata
491 private boolean configureSetInfo() {
492
493 Document doc = XMLConverter.newDOM();
494 this.list_sets_response = doc.createElement(GSXML.RESPONSE_ELEM);
495 Element list_sets_elem = doc.createElement(OAIXML.LIST_SETS);
496 this.list_sets_response.appendChild(list_sets_elem);
497 String set_name = this.coll_name;
498 String set_description = null;
499 Element name_elem = (Element)GSXML.getChildByTagName(this.config_info, OAIXML.SET_NAME);
500 if (name_elem!=null) {
501 set_name = GSXML.getNodeText(name_elem);
502 if (set_name.equals("")) {
503 set_name = this.coll_name; // default to coll name if can't find one
504 }
505 }
506 Element description_elem = (Element)GSXML.getChildByTagName(this.config_info, OAIXML.SET_DESCRIPTION);
507 if (description_elem!=null) {
508 set_description = GSXML.getNodeText(description_elem);
509 if (set_description.equals("")) {
510 set_description = null;
511 }
512 }
513 Element coll_set = OAIXML.createSet(doc, this.coll_name, set_name, set_description);
514 list_sets_elem.appendChild(coll_set);
515
516 // are we part of any super sets?
517 NodeList super_set_list = GSXML.getChildrenByTagName(this.config_info, OAIXML.OAI_SUPER_SET);
518 for (int i=0; i<super_set_list.getLength(); i++) {
519 String super_name = ((Element)super_set_list.item(i)).getAttribute(GSXML.NAME_ATT);
520 if (super_name != null && !super_name.equals("")) {
521 list_sets_elem.appendChild(OAIXML.createSet(doc, super_name, super_name, null));
522 }
523 }
524 return true;
525 }
526
527 /** create the metadata element used when processing ListRecords/GetRecord requests
528 */
529 protected Element createMetadataElement(Document doc, String prefix, DBInfo info) {
530 // the <metadata> element
531 Element metadata = doc.createElement(OAIXML.METADATA);
532 // the <oai:dc namespace...> element
533 Element prfx_str_elem = OAIXML.getMetadataPrefixElement(doc, prefix, OAIXML.oai_version);
534 metadata.appendChild(prfx_str_elem);
535
536 Element meta_format_element = GSXML.getNamedElement(this.meta_formats_definition, OAIXML.METADATA_FORMAT, GSXML.NAME_ATT, prefix);
537 NodeList elements = meta_format_element.getElementsByTagName(OAIXML.ELEMENT);
538 // for each element in the definition
539 for (int i=0; i<elements.getLength(); i++) {
540 Element e = (Element)elements.item(i);
541 Element map = (Element)GSXML.getChildByTagName(e, OAIXML.MAPPING);
542 if (map == null) {
543 // look up the element name
544 addMetadata(prfx_str_elem, e.getAttribute(GSXML.NAME_ATT), info);
545 } else {
546 // we go though the list of names in the mapping
547 addMetadata(prfx_str_elem, e.getAttribute(GSXML.NAME_ATT), map.getAttribute(OAIXML.SELECT), map.getAttribute(OAIXML.ELEMENTS), info);
548 }
549 }
550 // output any metadata that is not just a simple mapping
551 addCustomMetadata(prfx_str_elem, prefix, info);
552 return metadata;
553 }
554
555 /** a simple addMetadata where we look for meta_name metadata, and add as that name*/
556 protected void addMetadata(Element meta_list_elem, String meta_name, DBInfo info) {
557 Vector<String> values = info.getMultiInfo(meta_name);
558 for (int i=0; i<values.size(); i++) {
559 addMetadataElement(meta_list_elem, meta_name, values.get(i));
560 }
561 }
562
563 /** more complicated addMetadata - can add multiple items. */
564 protected void addMetadata(Element meta_list_elem, String new_meta_name, String select_type, String name_list, DBInfo info) {
565 String[] names = name_list.split(",");
566 for (int i=0; i<names.length; i++) {
567 Vector<String> values = info.getMultiInfo(names[i]);
568 if (values == null || values.size()==0) {
569 continue;
570 }
571 for (int j=0; j<values.size(); j++) {
572 addMetadataElement(meta_list_elem, new_meta_name, values.get(j));
573 if (select_type.equals(OAIXML.SELECT_SINGLE_VALUE)) {
574 return; // only want to add one value
575 }
576 }
577 if (select_type.equals(OAIXML.SELECT_FIRST_VALID_META)) {
578 return; // we have added all values of this meta elem
579 }
580 // otherwise, we will keep going through the list and add them all.
581 }
582 }
583
584 // specific metadata formats might need to do some custom metadata that is not
585 //just a standard mapping. eg oai_dc outputting an identifier that is a link
586 protected void addCustomMetadata(Element meta_list_elem, String prefix, DBInfo info) {
587
588 if (prefix.equals(OAIXML.META_FORMAT_DC)) {
589 // we want to add in another dc:identifier element with a link to the resource if possible
590 // try gs.OAIResourceURL first, then srclinkFile, then GS version of documnet
591 String gsURL = info.getInfo(OAIXML.GS_OAI_RESOURCE_URL);
592 if (gsURL.equals("")) {
593 String base_url = OAIXML.getBaseURL(); // e.g. e.g. http://host:port/greenstone3/oaiserver
594 // try srclinkFile
595 gsURL = info.getInfo("srclinkFile");
596 if (!gsURL.equals("")) {
597 // make up the link to the file
598 gsURL = base_url.replace("oaiserver", "") + "sites/" + this.site_name
599 + "/collect/" + this.coll_name + "/index/assoc/"
600 + info.getInfo("assocfilepath") + "/" + gsURL;
601 } else {
602 // no srclink file, lets provide a link to the greenstone doc
603 gsURL = base_url.replace("oaiserver", "library") + "/collection/" + this.coll_name + "/document/" + info.getInfo("Identifier");
604 }
605 }
606 // now we have the url link, add as metadata
607 addMetadataElement(meta_list_elem, "dc:identifier", gsURL);
608 }
609 }
610
611 /** create the actual metadata element for the list */
612 protected void addMetadataElement(Element meta_list_elem, String name, String value) {
613
614 Element meta = GSXML.createTextElement(meta_list_elem.getOwnerDocument(), name, value);
615 meta_list_elem.appendChild(meta);
616 }
617
618
619 /** create a header element used when processing requests like ListRecords/GetRecord/ListIdentifiers
620 */
621 protected Element createHeaderElement(Document doc, String oid, String oailastmodified) {
622 Element header = doc.createElement(OAIXML.HEADER);
623 Element identifier = doc.createElement(OAIXML.IDENTIFIER);
624 GSXML.setNodeText(identifier, coll_name + ":" + oid);
625 header.appendChild(identifier);
626 Element set_spec = doc.createElement(OAIXML.SET_SPEC);
627 GSXML.setNodeText(set_spec, coll_name);
628 header.appendChild(set_spec);
629 Element datestamp = doc.createElement(OAIXML.DATESTAMP);
630 GSXML.setNodeText(datestamp, oailastmodified);
631 header.appendChild(datestamp);
632 return header;
633 }
634
635 /** return the metadata information */
636 protected Element processListMetadataFormats(Element req) {
637 // the request sent here must contain an OID. see doListMetadataFormats() in OAIReceptionist
638 Element param = GSXML.getNamedElement(req, GSXML.PARAM_ELEM, GSXML.NAME_ATT, OAIXML.OID);
639 if (param == null) {
640 logger.error("An element containing the OID attribute not is present.");
641 return OAIXML.createErrorResponse(OAIXML.ID_DOES_NOT_EXIST, "");
642 }
643 String oid = param.getAttribute(GSXML.VALUE_ATT);
644 if (oid == null || oid.equals("")) {
645 logger.error("No OID is present in the request.");
646 return OAIXML.createErrorResponse(OAIXML.ID_DOES_NOT_EXIST, "");
647 }
648 ArrayList<String> oid_list = getChildrenIds(OAIXML.BROWSELIST);
649 if (oid_list == null || oid_list.contains(oid) == false) {
650 logger.error("OID: " + oid + " is not present in the database.");
651 Element e= OAIXML.createErrorResponse(OAIXML.ID_DOES_NOT_EXIST, "");
652// logger.error((new XMLConverter()).getPrettyString (e));
653 return e;
654 }
655
656 DBInfo info = null;
657 info = this.coll_db.getInfo(oid);
658 if (info == null) { //just double check
659 return OAIXML.createErrorResponse(OAIXML.OAI_SERVICE_UNAVAILABLE, "");
660 }
661
662 Document doc = XMLConverter.newDOM();
663 Element list_metadata_formats_response = doc.createElement(GSXML.RESPONSE_ELEM);
664
665 Element list_metadata_formats = doc.createElement(OAIXML.LIST_METADATA_FORMATS);
666 list_metadata_formats_response.appendChild(list_metadata_formats);
667 boolean has_meta_format = false;
668
669 // for each format in format_elements_map
670 Iterator<String> it = format_elements_map.keySet().iterator();
671 while (it.hasNext()) {
672 String format = it.next();
673 HashSet<String> set_of_elems = format_elements_map.get(format);
674 if (documentContainsMetadata(info, set_of_elems)) {
675 // add this format into the response
676 has_meta_format = true;
677 list_metadata_formats.appendChild(doc.importNode(format_response_map.get(format), true));
678 }
679 }
680
681 if (has_meta_format == false) {
682 logger.error("Specified metadata names are not contained in the database.");
683 return OAIXML.createErrorResponse(OAIXML.NO_METADATA_FORMATS, "");
684 } else {
685 return list_metadata_formats_response;
686 }
687 }
688
689 protected boolean documentContainsMetadata(DBInfo info, HashSet<String> set_of_elems) {
690 if (set_of_elems.size() == 0) {
691 return false;
692 }
693 Iterator<String> i = set_of_elems.iterator();
694 while (i.hasNext()) {
695 if (!info.getInfo(i.next()).equals("")) {
696 return true;
697 }
698 }
699 return false;
700 }
701
702 /** returns a list of the child ids in order, null if no children */
703 protected ArrayList<String> getChildrenIds(String node_id) {
704 DBInfo info = this.coll_db.getInfo(node_id);
705 if (info == null) {
706 return null;
707 }
708
709 String contains = info.getInfo("contains");
710 if (contains.equals("")) {
711 return null;
712 }
713 ArrayList<String> children = new ArrayList<String>();
714 StringTokenizer st = new StringTokenizer(contains, ";");
715 while (st.hasMoreTokens()) {
716 String child_id = st.nextToken().replaceAll("\"", node_id);
717 children.add(child_id);
718 }
719 return children;
720 }
721 /**method to check whether any of the 'metadata_names' is contained in the 'info'.
722 * The name may be in the form: <name>,<mapped name>, in which the mapped name is
723 * optional. The mapped name is looked up in the DBInfo; if not present, use the first
724 * name which is mendatory.
725 */
726 protected boolean containsMetadata(DBInfo info, String[] metadata_names) {
727 if (metadata_names == null) return false;
728 logger.info("checking metadata names in db.");
729 for(int i=0; i<metadata_names.length; i++) {
730 int index = metadata_names[i].indexOf(",");
731 String meta_name = (index == -1) ? metadata_names[i] :
732 metadata_names[i].substring(index + 1);
733
734 if(info.getInfo(meta_name).equals("") == false) {
735 return true;
736 }
737 }
738 return false;
739 }
740
741 protected long getDateStampMillis(DBInfo info) {
742 // gs.OAIDateStamp is in YYYY-MM-DD
743 String time_stamp = info.getInfo(OAIXML.GS_OAI_DATE_STAMP);
744 long millis = -1;
745 if (!time_stamp.equals("")) {
746 millis = OAIXML.getTime(time_stamp);
747 }
748 if (millis == -1) {
749 // oailastmodified is in seconds
750 time_stamp = info.getInfo(OAIXML.OAI_LASTMODIFIED);
751 if (!time_stamp.equals("")) {
752 millis = Long.parseLong(time_stamp)*1000;
753 }
754 }
755 return millis;
756
757
758 }
759}
760
761
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