001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied. See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 *
019 */
020 package org.apache.directory.shared.ldap.ldif;
021
022
023 import java.util.ArrayList;
024 import java.util.HashSet;
025 import java.util.List;
026 import java.util.Set;
027
028 import javax.naming.InvalidNameException;
029 import javax.naming.NamingException;
030
031 import org.apache.directory.shared.ldap.entry.Entry;
032 import org.apache.directory.shared.ldap.entry.EntryAttribute;
033 import org.apache.directory.shared.ldap.entry.Modification;
034 import org.apache.directory.shared.ldap.entry.ModificationOperation;
035 import org.apache.directory.shared.ldap.entry.client.ClientModification;
036 import org.apache.directory.shared.ldap.entry.client.DefaultClientAttribute;
037 import org.apache.directory.shared.ldap.name.AttributeTypeAndValue;
038 import org.apache.directory.shared.ldap.name.LdapDN;
039 import org.apache.directory.shared.ldap.name.Rdn;
040 import org.apache.directory.shared.ldap.util.AttributeUtils;
041
042
043 /**
044 * A helper class which provides methods to reverse a LDIF modification operation.
045 *
046 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
047 * @version $Rev$, $Date$
048 */
049 public class LdifRevertor
050 {
051 /** Two constants for the deleteOldRdn flag */
052 public static final boolean DELETE_OLD_RDN = true;
053 public static final boolean KEEP_OLD_RDN = false;
054
055 /**
056 * Compute a reverse LDIF of an AddRequest. It's simply a delete request
057 * of the added entry
058 *
059 * @param dn the dn of the added entry
060 * @return a reverse LDIF
061 */
062 public static LdifEntry reverseAdd( LdapDN dn )
063 {
064 LdifEntry entry = new LdifEntry();
065 entry.setChangeType( ChangeType.Delete );
066 entry.setDn( dn );
067 return entry;
068 }
069
070
071 /**
072 * Compute a reverse LDIF of a DeleteRequest. We have to get the previous
073 * entry in order to restore it.
074 *
075 * @param dn The deleted entry DN
076 * @param deletedEntry The entry which has been deleted
077 * @return A reverse LDIF
078 */
079 public static LdifEntry reverseDel( LdapDN dn, Entry deletedEntry ) throws NamingException
080 {
081 LdifEntry entry = new LdifEntry();
082
083 entry.setDn( dn );
084 entry.setChangeType( ChangeType.Add );
085
086 for ( EntryAttribute attribute : deletedEntry )
087 {
088 entry.addAttribute( attribute );
089 }
090
091 return entry;
092 }
093
094
095 /**
096 *
097 * Compute the reversed LDIF for a modify request. We will deal with the
098 * three kind of modifications :
099 * - add
100 * - remove
101 * - replace
102 *
103 * As the modifications should be issued in a reversed order ( ie, for
104 * the initials modifications {A, B, C}, the reversed modifications will
105 * be ordered like {C, B, A}), we will change the modifications order.
106 *
107 * @param dn the dn of the modified entry
108 * @param forwardModifications the modification items for the forward change
109 * @param modifiedEntry The modified entry. Necessary for the destructive modifications
110 * @return A reversed LDIF
111 * @throws NamingException If something went wrong
112 */
113 public static LdifEntry reverseModify( LdapDN dn, List<Modification> forwardModifications, Entry modifiedEntry )
114 throws NamingException
115 {
116 // First, protect the original entry by cloning it : we will modify it
117 Entry clonedEntry = ( Entry ) modifiedEntry.clone();
118
119 LdifEntry entry = new LdifEntry();
120 entry.setChangeType( ChangeType.Modify );
121
122 entry.setDn( dn );
123
124 // As the reversed modifications should be pushed in reversed order,
125 // we create a list to temporarily store the modifications.
126 List<Modification> reverseModifications = new ArrayList<Modification>();
127
128 // Loop through all the modifications. For each modification, we will
129 // have to apply it to the modified entry in order to be able to generate
130 // the reversed modification
131 for ( Modification modification : forwardModifications )
132 {
133 switch ( modification.getOperation() )
134 {
135 case ADD_ATTRIBUTE:
136 EntryAttribute mod = modification.getAttribute();
137
138 EntryAttribute previous = clonedEntry.get( mod.getId() );
139
140 if ( mod.equals( previous ) )
141 {
142 continue;
143 }
144
145 Modification reverseModification = new ClientModification( ModificationOperation.REMOVE_ATTRIBUTE,
146 mod );
147 reverseModifications.add( 0, reverseModification );
148 break;
149
150 case REMOVE_ATTRIBUTE:
151 mod = modification.getAttribute();
152
153 previous = clonedEntry.get( mod.getId() );
154
155 if ( previous == null )
156 {
157 // Nothing to do if the previous attribute didn't exist
158 continue;
159 }
160
161 if ( mod.get() == null )
162 {
163 reverseModification = new ClientModification( ModificationOperation.ADD_ATTRIBUTE, previous );
164 reverseModifications.add( 0, reverseModification );
165 break;
166 }
167
168 reverseModification = new ClientModification( ModificationOperation.ADD_ATTRIBUTE, mod );
169 reverseModifications.add( 0, reverseModification );
170 break;
171
172 case REPLACE_ATTRIBUTE:
173 mod = modification.getAttribute();
174
175 previous = clonedEntry.get( mod.getId() );
176
177 /*
178 * The server accepts without complaint replace
179 * modifications to non-existing attributes in the
180 * entry. When this occurs nothing really happens
181 * but this method freaks out. To prevent that we
182 * make such no-op modifications produce the same
183 * modification for the reverse direction which should
184 * do nothing as well.
185 */
186 if ( ( mod.get() == null ) && ( previous == null ) )
187 {
188 reverseModification = new ClientModification( ModificationOperation.REPLACE_ATTRIBUTE,
189 new DefaultClientAttribute( mod.getId() ) );
190 reverseModifications.add( 0, reverseModification );
191 continue;
192 }
193
194 if ( mod.get() == null )
195 {
196 reverseModification = new ClientModification( ModificationOperation.REPLACE_ATTRIBUTE, previous );
197 reverseModifications.add( 0, reverseModification );
198 continue;
199 }
200
201 if ( previous == null )
202 {
203 EntryAttribute emptyAttribute = new DefaultClientAttribute( mod.getId() );
204 reverseModification = new ClientModification( ModificationOperation.REPLACE_ATTRIBUTE,
205 emptyAttribute );
206 reverseModifications.add( 0, reverseModification );
207 continue;
208 }
209
210 reverseModification = new ClientModification( ModificationOperation.REPLACE_ATTRIBUTE, previous );
211 reverseModifications.add( 0, reverseModification );
212 break;
213
214 default:
215 break; // Do nothing
216
217 }
218
219 AttributeUtils.applyModification( clonedEntry, modification );
220
221 }
222
223 // Special case if we don't have any reverse modifications
224 if ( reverseModifications.size() == 0 )
225 {
226 throw new IllegalArgumentException( "Could not deduce reverse modifications from provided modifications: "
227 + forwardModifications );
228 }
229
230 // Now, push the reversed list into the entry
231 for ( Modification modification : reverseModifications )
232 {
233 entry.addModificationItem( modification );
234 }
235
236 // Return the reverted entry
237 return entry;
238 }
239
240
241 /**
242 * Compute a reverse LDIF for a forward change which if in LDIF format
243 * would represent a Move operation. Hence there is no newRdn in the
244 * picture here.
245 *
246 * @param newSuperiorDn the new parent dn to be (must not be null)
247 * @param modifiedDn the dn of the entry being moved (must not be null)
248 * @return a reverse LDIF
249 * @throws NamingException if something went wrong
250 */
251 public static LdifEntry reverseMove( LdapDN newSuperiorDn, LdapDN modifiedDn ) throws NamingException
252 {
253 LdifEntry entry = new LdifEntry();
254 LdapDN currentParent = null;
255 Rdn currentRdn = null;
256 LdapDN newDn = null;
257
258 if ( newSuperiorDn == null )
259 {
260 throw new NullPointerException( "newSuperiorDn must not be null" );
261 }
262
263 if ( modifiedDn == null )
264 {
265 throw new NullPointerException( "modifiedDn must not be null" );
266 }
267
268 if ( modifiedDn.size() == 0 )
269 {
270 throw new IllegalArgumentException( "Don't think about moving the rootDSE." );
271 }
272
273 currentParent = ( LdapDN ) modifiedDn.clone();
274 currentRdn = currentParent.getRdn();
275 currentParent.remove( currentParent.size() - 1 );
276
277 newDn = ( LdapDN ) newSuperiorDn.clone();
278 newDn.add( modifiedDn.getRdn() );
279
280 entry.setChangeType( ChangeType.ModDn );
281 entry.setDn( newDn );
282 entry.setNewRdn( currentRdn.getUpName() );
283 entry.setNewSuperior( currentParent.getUpName() );
284 entry.setDeleteOldRdn( false );
285 return entry;
286 }
287
288
289 /**
290 * A small helper class to compute the simple revert.
291 */
292 private static LdifEntry revertEntry( List<LdifEntry> entries, Entry entry, LdapDN newDn,
293 LdapDN newSuperior, Rdn oldRdn, Rdn newRdn ) throws InvalidNameException
294 {
295 LdifEntry reverted = new LdifEntry();
296
297 // We have a composite old RDN, something like A=a+B=b
298 // It does not matter if the RDNs overlap
299 reverted.setChangeType( ChangeType.ModRdn );
300
301 if ( newSuperior != null )
302 {
303 LdapDN restoredDn = (LdapDN)((LdapDN)newSuperior.clone()).add( newRdn );
304 reverted.setDn( restoredDn );
305 }
306 else
307 {
308 reverted.setDn( newDn );
309 }
310
311 reverted.setNewRdn( oldRdn.getUpName() );
312
313 // Is the newRdn's value present in the entry ?
314 // ( case 3, 4 and 5)
315 // If keepOldRdn = true, we cover case 4 and 5
316 boolean keepOldRdn = entry.contains( newRdn.getNormType(), newRdn.getNormValue() );
317
318 reverted.setDeleteOldRdn( !keepOldRdn );
319
320 if ( newSuperior != null )
321 {
322 LdapDN oldSuperior = ( LdapDN ) entry.getDn().clone();
323
324 oldSuperior.remove( oldSuperior.size() - 1 );
325 reverted.setNewSuperior( oldSuperior.getUpName() );
326 }
327
328 return reverted;
329 }
330
331
332 /**
333 * A helper method to generate the modified attribute after a rename.
334 */
335 private static LdifEntry generateModify( LdapDN parentDn, Entry entry, Rdn oldRdn, Rdn newRdn )
336 {
337 LdifEntry restored = new LdifEntry();
338 restored.setChangeType( ChangeType.Modify );
339
340 // We have to use the parent DN, the entry has already
341 // been renamed
342 restored.setDn( parentDn );
343
344 for ( AttributeTypeAndValue ava:newRdn )
345 {
346 // No need to add something which has already been added
347 // in the previous modification
348 if ( !entry.contains( ava.getNormType(), ava.getNormValue().getString() ) &&
349 !(ava.getNormType().equals( oldRdn.getNormType() ) &&
350 ava.getNormValue().equals( oldRdn.getNormValue() ) ) )
351 {
352 // Create the modification, which is an Remove
353 Modification modification = new ClientModification(
354 ModificationOperation.REMOVE_ATTRIBUTE,
355 new DefaultClientAttribute( ava.getUpType(), ava.getUpValue().getString() ) );
356
357 restored.addModificationItem( modification );
358 }
359 }
360
361 return restored;
362 }
363
364
365 /**
366 * A helper method which generates a reverted entry
367 */
368 private static LdifEntry generateReverted( LdapDN newSuperior, Rdn newRdn, LdapDN newDn,
369 Rdn oldRdn, boolean deleteOldRdn ) throws InvalidNameException
370 {
371 LdifEntry reverted = new LdifEntry();
372 reverted.setChangeType( ChangeType.ModRdn );
373
374 if ( newSuperior != null )
375 {
376 LdapDN restoredDn = (LdapDN)((LdapDN)newSuperior.clone()).add( newRdn );
377 reverted.setDn( restoredDn );
378 }
379 else
380 {
381 reverted.setDn( newDn );
382 }
383
384 reverted.setNewRdn( oldRdn.getUpName() );
385
386 if ( newSuperior != null )
387 {
388 LdapDN oldSuperior = ( LdapDN ) newDn.clone();
389
390 oldSuperior.remove( oldSuperior.size() - 1 );
391 reverted.setNewSuperior( oldSuperior.getUpName() );
392 }
393
394 // Delete the newRDN values
395 reverted.setDeleteOldRdn( deleteOldRdn );
396
397 return reverted;
398 }
399
400
401 /**
402 * Revert a DN to it's previous version by removing the first RDN and adding the given RDN.
403 * It's a rename operation. The biggest issue is that we have many corner cases, depending
404 * on the RDNs we are manipulating, and on the content of the initial entry.
405 *
406 * @param entry The initial Entry
407 * @param newRdn The new RDN
408 * @param deleteOldRdn A flag which tells to delete the old RDN AVAs
409 * @return A list of LDIF reverted entries
410 * @throws NamingException If the name reverting failed
411 */
412 public static List<LdifEntry> reverseRename( Entry entry, Rdn newRdn, boolean deleteOldRdn ) throws NamingException
413 {
414 return reverseMoveAndRename( entry, null, newRdn, deleteOldRdn );
415 }
416
417
418 /**
419 * Revert a DN to it's previous version by removing the first RDN and adding the given RDN.
420 * It's a rename operation. The biggest issue is that we have many corner cases, depending
421 * on the RDNs we are manipulating, and on the content of the initial entry.
422 *
423 * @param entry The initial Entry
424 * @param newSuperior The new superior DN (can be null if it's just a rename)
425 * @param newRdn The new RDN
426 * @param deleteOldRdn A flag which tells to delete the old RDN AVAs
427 * @return A list of LDIF reverted entries
428 * @throws NamingException If the name reverting failed
429 */
430 public static List<LdifEntry> reverseMoveAndRename( Entry entry, LdapDN newSuperior, Rdn newRdn, boolean deleteOldRdn ) throws NamingException
431 {
432 LdapDN parentDn = entry.getDn();
433 LdapDN newDn = null;
434
435 if ( newRdn == null )
436 {
437 throw new NullPointerException( "The newRdn must not be null" );
438 }
439
440 if ( parentDn == null )
441 {
442 throw new NullPointerException( "The modified Dn must not be null" );
443 }
444
445 if ( parentDn.size() == 0 )
446 {
447 throw new IllegalArgumentException( "Don't think about renaming the rootDSE." );
448 }
449
450 parentDn = ( LdapDN ) entry.getDn().clone();
451 Rdn oldRdn = parentDn.getRdn();
452
453 newDn = ( LdapDN ) parentDn.clone();
454 newDn.remove( newDn.size() - 1 );
455 newDn.add( newRdn );
456
457 List<LdifEntry> entries = new ArrayList<LdifEntry>( 1 );
458 LdifEntry reverted = new LdifEntry();
459
460 // Start with the cases here
461 if ( newRdn.size() == 1 )
462 {
463 // We have a simple new RDN, something like A=a
464 if ( ( oldRdn.size() == 1 ) && ( oldRdn.equals( newRdn ) ) )
465 {
466 // We have a simple old RDN, something like A=a
467 // If the values overlap, we can't rename the entry, just get out
468 // with an error
469 throw new NamingException( "Can't rename an entry using the same name ..." );
470 }
471
472 reverted =
473 revertEntry( entries, entry, newDn, newSuperior, oldRdn, newRdn );
474
475 entries.add( reverted );
476 }
477 else
478 {
479 // We have a composite new RDN, something like A=a+B=b
480 if ( oldRdn.size() == 1 )
481 {
482 // The old RDN is simple
483 boolean overlapping = false;
484 boolean existInEntry = false;
485
486 // Does it overlap ?
487 // Is the new RDN AVAs contained into the entry?
488 for ( AttributeTypeAndValue atav:newRdn )
489 {
490 if ( atav.equals( oldRdn.getAtav() ) )
491 {
492 // They overlap
493 overlapping = true;
494 }
495 else
496 {
497 if ( entry.contains( atav.getNormType(), atav.getNormValue().getString() ) )
498 {
499 existInEntry = true;
500 }
501 }
502 }
503
504 if ( overlapping )
505 {
506 // The new RDN includes the old one
507 if ( existInEntry )
508 {
509 // Some of the new RDN AVAs existed in the entry
510 // We have to restore them, but we also have to remove
511 // the new values
512 reverted = generateReverted( newSuperior, newRdn, newDn, oldRdn, KEEP_OLD_RDN );
513
514 entries.add( reverted );
515
516 // Now, restore the initial values
517 LdifEntry restored = generateModify( parentDn, entry, oldRdn, newRdn );
518
519 entries.add( restored );
520 }
521 else
522 {
523 // This is the simplest case, we don't have to restore
524 // some existing values (case 8.1 and 9.1)
525 reverted = generateReverted( newSuperior, newRdn, newDn, oldRdn, DELETE_OLD_RDN );
526
527 entries.add( reverted );
528 }
529 }
530 else
531 {
532 if ( existInEntry )
533 {
534 // Some of the new RDN AVAs existed in the entry
535 // We have to restore them, but we also have to remove
536 // the new values
537 reverted = generateReverted( newSuperior, newRdn, newDn, oldRdn, KEEP_OLD_RDN );
538
539 entries.add( reverted );
540
541 LdifEntry restored = generateModify( parentDn, entry, oldRdn, newRdn );
542
543 entries.add( restored );
544 }
545 else
546 {
547 // A much simpler case, as we just have to remove the newRDN
548 reverted = generateReverted( newSuperior, newRdn, newDn, oldRdn, DELETE_OLD_RDN );
549
550 entries.add( reverted );
551 }
552 }
553 }
554 else
555 {
556 // We have a composite new RDN, something like A=a+B=b
557 // Does the RDN overlap ?
558 boolean overlapping = false;
559 boolean existInEntry = false;
560
561 Set<AttributeTypeAndValue> oldAtavs = new HashSet<AttributeTypeAndValue>();
562
563 // We first build a set with all the oldRDN ATAVs
564 for ( AttributeTypeAndValue atav:oldRdn )
565 {
566 oldAtavs.add( atav );
567 }
568
569 // Now we loop on the newRDN ATAVs to evaluate if the Rdns are overlaping
570 // and if the newRdn ATAVs are present in the entry
571 for ( AttributeTypeAndValue atav:newRdn )
572 {
573 if ( oldAtavs.contains( atav ) )
574 {
575 overlapping = true;
576 }
577 else if ( entry.contains( atav.getNormType(), atav.getNormValue().getString() ) )
578 {
579 existInEntry = true;
580 }
581 }
582
583 if ( overlapping )
584 {
585 // They overlap
586 if ( existInEntry )
587 {
588 // In this case, we have to reestablish the removed ATAVs
589 // (Cases 12.2 and 13.2)
590 reverted = generateReverted( newSuperior, newRdn, newDn, oldRdn, KEEP_OLD_RDN );
591
592 entries.add( reverted );
593 }
594 else
595 {
596 // We can simply remove all the new RDN atavs, as the
597 // overlapping values will be re-created.
598 // (Cases 12.1 and 13.1)
599 reverted = generateReverted( newSuperior, newRdn, newDn, oldRdn, DELETE_OLD_RDN );
600
601 entries.add( reverted );
602 }
603 }
604 else
605 {
606 // No overlapping
607 if ( existInEntry )
608 {
609 // In this case, we have to reestablish the removed ATAVs
610 // (Cases 10.2 and 11.2)
611 reverted = generateReverted( newSuperior, newRdn, newDn, oldRdn, KEEP_OLD_RDN );
612
613 entries.add( reverted );
614
615 LdifEntry restored = generateModify( parentDn, entry, oldRdn, newRdn );
616
617 entries.add( restored );
618 }
619 else
620 {
621 // We are safe ! We can delete all the new Rdn ATAVs
622 // (Cases 10.1 and 11.1)
623 reverted = generateReverted( newSuperior, newRdn, newDn, oldRdn, DELETE_OLD_RDN );
624
625 entries.add( reverted );
626 }
627 }
628 }
629 }
630
631 return entries;
632 }
633 }