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1
16 package org.apache.cocoon.components.source.impl;
17
18 import java.io.ByteArrayInputStream  ;
19 import java.io.ByteArrayOutputStream ;
20 import java.io.IOException ;
21 import java.io.InputStream ;
22 import java.io.OutputStream ;
23 import java.net.MalformedURLException ;
24
25 import javax.xml.transform.TransformerFactory ;
26 import javax.xml.transform.sax.SAXTransformerFactory ;
27 import javax.xml.transform.sax.TransformerHandler ;
28 import javax.xml.transform.stream.StreamResult ;
29
30 import org.apache.avalon.framework.context.Context;
31 import org.apache.avalon.framework.logger.AbstractLogEnabled;
32 import org.apache.avalon.framework.logger.Logger;
33 import org.apache.avalon.framework.service.ServiceManager;
34 import org.apache.avalon.framework.service.ServiceSelector;
35 import org.apache.cocoon.CascadingIOException;
36 import org.apache.cocoon.ProcessingException;
37 import org.apache.cocoon.ResourceNotFoundException;
38 import org.apache.cocoon.components.source.helpers.SourceCredential;
39 import org.apache.cocoon.serialization.Serializer;
40 import org.apache.cocoon.xml.IncludeXMLConsumer;
41 import org.apache.excalibur.source.ModifiableSource;
42 import org.apache.excalibur.source.Source;
43 import org.apache.excalibur.source.SourceException;
44 import org.apache.excalibur.source.SourceValidity;
45 import org.apache.excalibur.xml.sax.XMLizable;
46 import org.xml.sax.ContentHandler ;
47 import org.xml.sax.SAXException ;
48 import org.xml.sax.helpers.AttributesImpl ;
49 import org.xmldb.api.DatabaseManager;
50 import org.xmldb.api.base.Collection;
51 import org.xmldb.api.base.Resource;
52 import org.xmldb.api.base.ResourceIterator;
53 import org.xmldb.api.base.ResourceSet;
54 import org.xmldb.api.base.XMLDBException;
55 import org.xmldb.api.modules.CollectionManagementService;
56 import org.xmldb.api.modules.XMLResource;
57 import org.xmldb.api.modules.XPathQueryService;
58
59
67 public class XMLDBSource extends AbstractLogEnabled
68 implements Source, ModifiableSource, XMLizable {
69
70
74
75 public static final String URI = "http://apache.org/cocoon/xmldb/1.0";
76
77
78 public static final String PREFIX = "db";
79
80
81 protected static final String COLLECTIONS = "collections";
82
83 protected static final String QCOLLECTIONS = PREFIX + ":" + COLLECTIONS;
84
85 protected static final String RESOURCE_COUNT_ATTR = "resources";
86
87 protected static final String COLLECTION_COUNT_ATTR = "collections";
88 protected static final String COLLECTION_BASE_ATTR = "base";
89
90
91 protected static final String COLLECTION = "collection";
92
93 protected static final String QCOLLECTION = PREFIX + ":" + COLLECTION;
94
95
96 protected static final String RESOURCE = "resource";
97
98 protected static final String QRESOURCE = PREFIX + ":" + RESOURCE;
99
100 protected static final String NAME_ATTR = "name";
101
102
103 protected static final String RESULTSET = "results";
104
105 protected static final String QRESULTSET = PREFIX + ":" + RESULTSET;
106 protected static final String QUERY_ATTR = "query";
107 protected static final String RESULTS_COUNT_ATTR = "resources";
108
109
110 protected static final String RESULT = "result";
111
112 protected static final String QRESULT = PREFIX + ":" + RESULT;
113 protected static final String RESULT_DOCID_ATTR = "docid";
114 protected static final String RESULT_ID_ATTR = "id";
115
116 protected static final String CDATA = "CDATA";
117
118
122
123 protected String url;
124
125
126 protected String user;
127
128
129 protected String password;
130
131
132 protected String query;
133
134
135 protected String systemId;
136
137
138 protected final ServiceManager manager;
139
140
141 protected XMLDBOutputStream os;
142
143
144 protected final Context context;
145
146
154 public XMLDBSource(Logger logger,
155 SourceCredential credential,
156 String url,
157 ServiceManager manager,
158 Context context) {
159 enableLogging(logger);
160 this.context = context;
161 this.manager = manager;
162
163 this.user = credential.getPrincipal();
164 this.password = credential.getPassword();
165
166 int start = url.indexOf('#');
168 if (start != -1) {
169 this.url = url.substring(0, start);
170 this.query = url.substring(start + 1);
171 } else {
172 this.url = url;
173 }
174 this.os = null;
175 }
176
177
181 public void toSAX(ContentHandler handler) throws SAXException {
182 try {
183 if (url.endsWith("/")) {
184 this.collectionToSAX(handler);
185 } else {
186 this.resourceToSAX(handler);
187 }
188 } catch (ProcessingException pe) {
189 throw new SAXException ("ProcessingException", pe);
190 }
191 }
192
193 private void resourceToSAX(ContentHandler handler)
194 throws SAXException , ProcessingException {
195
196 final String col = url.substring(0, url.lastIndexOf('/'));
197 final String res = url.substring(url.lastIndexOf('/') + 1);
198
199 Collection collection = null;
200 try {
201 collection = DatabaseManager.getCollection(col, user, password);
202 if (collection == null) {
203 throw new ResourceNotFoundException("Document " + url + " not found");
204 }
205
206 XMLResource xmlResource = (XMLResource) collection.getResource(res);
207 if (xmlResource == null) {
208 throw new ResourceNotFoundException("Document " + url + " not found");
209 }
210
211 if (query != null) {
212 if (getLogger().isDebugEnabled()) {
214 getLogger().debug("Querying resource " + res + " from collection " + url + "; query= " + this.query);
215 }
216
217 queryToSAX(handler, collection, res);
218 } else {
219 if (getLogger().isDebugEnabled()) {
221 getLogger().debug("Obtaining resource " + res + " from collection " + col);
222 }
223
224 xmlResource.getContentAsSAX(handler);
225 }
226 } catch (XMLDBException xde) {
227 String error = "Unable to fetch content. Error "
228 + xde.errorCode + ": " + xde.getMessage();
229 throw new SAXException (error, xde);
230 } finally {
231 if (collection != null) {
232 try {
233 collection.close();
234 } catch (XMLDBException ignored) {
235 }
236 }
237 }
238 }
239
240 private void collectionToSAX(ContentHandler handler)
241 throws SAXException , ProcessingException {
242
243 AttributesImpl attributes = new AttributesImpl ();
244
245 Collection collection = null;
246 try {
247 collection = DatabaseManager.getCollection(url, user, password);
248 if (collection == null) {
249 throw new ResourceNotFoundException("Collection " + url +
250 " not found");
251 }
252
253 if (query != null) {
254 if (getLogger().isDebugEnabled()) {
256 getLogger().debug("Querying collection " + url + "; query= " + this.query);
257 }
258
259 queryToSAX(handler, collection, null);
260 } else {
261 if (getLogger().isDebugEnabled()) {
263 getLogger().debug("Listing collection " + url);
264 }
265
266 final String nresources = Integer.toString(collection.getResourceCount());
267 attributes.addAttribute("", RESOURCE_COUNT_ATTR,
268 RESOURCE_COUNT_ATTR, "CDATA", nresources);
269 final String ncollections = Integer.toString(collection.getChildCollectionCount());
270 attributes.addAttribute("", COLLECTION_COUNT_ATTR,
271 COLLECTION_COUNT_ATTR, "CDATA", ncollections);
272 attributes.addAttribute("", COLLECTION_BASE_ATTR,
273 COLLECTION_BASE_ATTR, "CDATA", url);
274
275 handler.startDocument();
276 handler.startPrefixMapping(PREFIX, URI);
277 handler.startElement(URI, COLLECTIONS, QCOLLECTIONS, attributes);
278
279 String [] collections = collection.listChildCollections();
281 for (int i = 0; i < collections.length; i++) {
282 attributes.clear();
283 attributes.addAttribute("", NAME_ATTR, NAME_ATTR, CDATA, collections[i]);
284 handler.startElement(URI, COLLECTION, QCOLLECTION, attributes);
285 handler.endElement(URI, COLLECTION, QCOLLECTION);
286 }
287
288 String [] resources = collection.listResources();
290 for (int i = 0; i < resources.length; i++) {
291 attributes.clear();
292 attributes.addAttribute("", NAME_ATTR, NAME_ATTR, CDATA, resources[i]);
293 handler.startElement(URI, RESOURCE, QRESOURCE, attributes);
294 handler.endElement(URI, RESOURCE, QRESOURCE);
295 }
296
297 handler.endElement(URI, COLLECTIONS, QCOLLECTIONS);
298 handler.endPrefixMapping(PREFIX);
299 handler.endDocument();
300 }
301 } catch (XMLDBException xde) {
302 String error = "Collection listing failed. Error " + xde.errorCode + ": " + xde.getMessage();
303 throw new SAXException (error, xde);
304 } finally {
305 if (collection != null) {
306 try {
307 collection.close();
308 } catch (XMLDBException ignored) {
309 }
310 }
311 }
312 }
313
314 private void queryToSAX(ContentHandler handler, Collection collection, String resource)
315 throws SAXException {
316
317 AttributesImpl attributes = new AttributesImpl ();
318
319 try {
320 XPathQueryService service =
321 (XPathQueryService) collection.getService("XPathQueryService", "1.0");
322 ResourceSet resultSet = (resource == null) ?
323 service.query(query) : service.queryResource(resource, query);
324
325 attributes.addAttribute("", QUERY_ATTR, QUERY_ATTR, "CDATA", query);
326 attributes.addAttribute("", RESULTS_COUNT_ATTR,
327 RESULTS_COUNT_ATTR, "CDATA", Long.toString(resultSet.getSize()));
328
329 handler.startDocument();
330 handler.startPrefixMapping(PREFIX, URI);
331 handler.startElement(URI, RESULTSET, QRESULTSET, attributes);
332
333 IncludeXMLConsumer includeHandler = new IncludeXMLConsumer(handler);
334
335 ResourceIterator results = resultSet.getIterator();
337 while (results.hasMoreResources()) {
338 XMLResource result = (XMLResource)results.nextResource();
339
340 final String id = result.getId();
341 final String documentId = result.getDocumentId();
342
343 attributes.clear();
344 if (id != null) {
345 attributes.addAttribute("", RESULT_ID_ATTR, RESULT_ID_ATTR,
346 CDATA, id);
347 }
348 if (documentId != null) {
349 attributes.addAttribute("", RESULT_DOCID_ATTR, RESULT_DOCID_ATTR,
350 CDATA, documentId);
351 }
352
353 handler.startElement(URI, RESULT, QRESULT, attributes);
354 result.getContentAsSAX(includeHandler);
355 handler.endElement(URI, RESULT, QRESULT);
356 }
357
358 handler.endElement(URI, RESULTSET, QRESULTSET);
359 handler.endPrefixMapping(PREFIX);
360 handler.endDocument();
361 } catch (XMLDBException xde) {
362 String error = "Query failed. Error " + xde.errorCode + ": " + xde.getMessage();
363 throw new SAXException (error, xde);
364 }
365 }
366
367 public void recycle() {
368 this.url = null;
369 this.user = null;
370 this.password = null;
371 this.query = null;
372 }
373
374 public String getURI() {
375 return url;
376 }
377
378 public long getContentLength() {
379 return -1;
380 }
381
382 public long getLastModified() {
383 return 0;
384 }
385
386 public boolean exists() {
387 final String col = url.substring(0, url.lastIndexOf('/'));
388 final String res = url.substring(url.lastIndexOf('/') + 1);
389 boolean result = true;
390
391
392 if (getLogger().isDebugEnabled()) {
393 getLogger().debug("Testing existence of resource `" + res + "' from collection `" + url + "'; query (ignored) = `" + this.query + "'");
394 }
395
396 Collection collection = null;
397 try {
398 collection = DatabaseManager.getCollection(col, user, password);
399 if (collection == null) {
400 result = false;
401 } else {
402 XMLResource xmlResource = (XMLResource) collection.getResource(res);
403 if (xmlResource == null) {
404 result = false;
405 }
406 }
407 } catch (XMLDBException xde) {
408 result = false;
409 } finally {
410 if (collection != null) {
411 try {
412 collection.close();
413 } catch (XMLDBException ignored) {
414 }
415 }
416 }
417
418 return result;
419 }
420
421 public String getMimeType() {
422 return null;
423 }
424
425 public String getScheme() {
426 return url.substring(url.indexOf('/') - 1);
427 }
428
429 public SourceValidity getValidity() {
430 return null;
431 }
432
433 public void refresh() {
434 }
435
436
439 public InputStream getInputStream()
440 throws IOException {
441
442 ServiceSelector serializerSelector = null;
443 Serializer serializer = null;
444 try {
446 TransformerFactory tf = TransformerFactory.newInstance();
447 TransformerHandler th =
448 ((SAXTransformerFactory ) tf).newTransformerHandler();
449 ByteArrayOutputStream bOut = new ByteArrayOutputStream ();
450 StreamResult result = new StreamResult (bOut);
451 th.setResult(result);
452
453 toSAX(th);
454
455 return new ByteArrayInputStream (bOut.toByteArray());
456 } catch (Exception e) {
457 throw new CascadingIOException("Exception during processing of " + getURI(), e);
458 } finally {
459 if (serializer != null) {
460 serializerSelector.release(serializer);
461 }
462 if (serializerSelector != null) {
463 manager.release(serializerSelector);
464 }
465 }
466 }
467
468
471 public OutputStream getOutputStream() throws IOException , MalformedURLException {
472 if (query != null) {
473 throw new MalformedURLException ("Cannot modify a resource that includes an XPATH expression");
474 }
475 this.os = new XMLDBOutputStream();
476 return this.os;
477 }
478
479 private void writeOutputStream(String content) throws SourceException {
480 String name = null;
481 String base = null;
482
483 try {
484 if (this.url.endsWith("/")) {
485 name = "";
486 base = this.url.substring(0, this.url.length() - 1);
487 } else {
488 base = this.url.substring(0, this.url.lastIndexOf("/"));
489 name = this.url.substring(this.url.lastIndexOf("/")+1);
490 }
491 Collection collection = DatabaseManager.getCollection(base, user, password);
492
493 if (name.equals("")) {
494 name = collection.createId();
495 this.url += name;
496 }
497 Resource resource = collection.createResource(name, "XMLResource");
498
499 resource.setContent(content);
500 collection.storeResource(resource);
501
502 getLogger().debug("Written to resource " + name);
503 } catch (XMLDBException e) {
504 String message = "Failed to create resource " + name + ": " + e.errorCode;
505 getLogger().debug(message, e);
506 throw new SourceException(message);
507 }
508 }
509
510
513 public void delete() throws SourceException {
514 String base = null;
515 String name = null;
516 if (this.url.endsWith("/")) {
517 try {
518 String k = this.url.substring(0, this.url.length() - 1);
520
521 base = k.substring(0, k.lastIndexOf("/"));
522 name = k.substring(k.lastIndexOf("/")+1);
523
524 Collection collection = DatabaseManager.getCollection(base, user, password);
525
526 CollectionManagementService service =
527 (CollectionManagementService) collection.getService("CollectionManagementService", "1.0");
528 service.removeCollection(name);
529 } catch (XMLDBException e) {
530 String message = "Failed to remove collection " + name + ": " + e.errorCode;
531 getLogger().error(message, e);
532 throw new SourceException(message);
533 }
534 } else {
535 try {
536 base = this.url.substring(0, this.url.lastIndexOf("/"));
537 name = this.url.substring(this.url.lastIndexOf("/")+1);
538
539 Collection collection = DatabaseManager.getCollection(base, user, password);
540
541 Resource resource = collection.getResource(name);
542 if (resource == null) {
543 String message = "Resource " + name + " does not exist";
544 getLogger().debug(message);
545 throw new SourceException(message);
546 } else {
547 collection.removeResource(resource);
548 getLogger().debug("Removed resource: "+ name);
549 }
550 } catch (XMLDBException e) {
551 String message = "Failed to delete resource " + name + ": " + e.errorCode;
552 getLogger().debug(message, e);
553 throw new SourceException(message);
554 }
555 }
556 }
557
558
564 public boolean canCancel(OutputStream stream) {
565 return !this.os.isClosed();
566 }
567
568
574 public void cancel(OutputStream stream) throws IOException {
575 this.os.cancel();
576 this.os = null;
577 }
578
579 public class XMLDBOutputStream extends OutputStream {
580
581 private ByteArrayOutputStream baos;
582 private boolean isClosed;
583 public XMLDBOutputStream() {
584 baos = new ByteArrayOutputStream ();
585 isClosed = false;
586 }
587
588 public void write(int b) throws IOException {
589 baos.write(b);
590 }
591
592 public void write(byte b[]) throws IOException {
593 baos.write(b);
594 }
595
596 public void write(byte b[], int off, int len) throws IOException {
597 baos.write(b, off, len);
598 }
599
600 public void close() throws IOException , SourceException {
601 if (!isClosed) {
602 writeOutputStream(baos.toString());
603 baos.close();
604 this.isClosed = true;
605 }
606 }
607
608 public void flush() throws IOException {
609 }
610
611 public int size() {
612 return baos.size();
613 }
614
615 public boolean isClosed() {
616 return this.isClosed;
617 }
618 public void cancel() {
619 this.isClosed = true;
620 }
621 }
622 }
623 |
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