001/*
002 * Copyright 2007-2020 Ping Identity Corporation
003 * All Rights Reserved.
004 */
005/*
006 * Copyright 2007-2020 Ping Identity Corporation
007 *
008 * Licensed under the Apache License, Version 2.0 (the "License");
009 * you may not use this file except in compliance with the License.
010 * You may obtain a copy of the License at
011 *
012 *    http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing, software
015 * distributed under the License is distributed on an "AS IS" BASIS,
016 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
017 * See the License for the specific language governing permissions and
018 * limitations under the License.
019 */
020/*
021 * Copyright (C) 2008-2020 Ping Identity Corporation
022 *
023 * This program is free software; you can redistribute it and/or modify
024 * it under the terms of the GNU General Public License (GPLv2 only)
025 * or the terms of the GNU Lesser General Public License (LGPLv2.1 only)
026 * as published by the Free Software Foundation.
027 *
028 * This program is distributed in the hope that it will be useful,
029 * but WITHOUT ANY WARRANTY; without even the implied warranty of
030 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
031 * GNU General Public License for more details.
032 *
033 * You should have received a copy of the GNU General Public License
034 * along with this program; if not, see <http://www.gnu.org/licenses>.
035 */
036package com.unboundid.ldap.sdk.controls;
037
038
039
040import java.util.ArrayList;
041
042import com.unboundid.asn1.ASN1Constants;
043import com.unboundid.asn1.ASN1Element;
044import com.unboundid.asn1.ASN1Enumerated;
045import com.unboundid.asn1.ASN1Exception;
046import com.unboundid.asn1.ASN1Long;
047import com.unboundid.asn1.ASN1OctetString;
048import com.unboundid.asn1.ASN1Sequence;
049import com.unboundid.ldap.sdk.Control;
050import com.unboundid.ldap.sdk.DecodeableControl;
051import com.unboundid.ldap.sdk.LDAPException;
052import com.unboundid.ldap.sdk.ResultCode;
053import com.unboundid.ldap.sdk.SearchResultEntry;
054import com.unboundid.util.Debug;
055import com.unboundid.util.NotMutable;
056import com.unboundid.util.StaticUtils;
057import com.unboundid.util.ThreadSafety;
058import com.unboundid.util.ThreadSafetyLevel;
059import com.unboundid.util.Validator;
060
061import static com.unboundid.ldap.sdk.controls.ControlMessages.*;
062
063
064
065/**
066 * This class provides an implementation of the entry change notification
067 * control as defined in draft-ietf-ldapext-psearch.  It will be returned in
068 * search result entries that match the criteria associated with a persistent
069 * search (see the {@link PersistentSearchRequestControl} class) and have been
070 * changed in a way associated with the registered change types for that search.
071 * <BR><BR>
072 * The information that can be included in an entry change notification control
073 * includes:
074 * <UL>
075 *   <LI>A change type, which indicates the type of operation that was performed
076 *       to trigger this entry change notification control.  It will be one of
077 *       the values of the {@link PersistentSearchChangeType} enum.</LI>
078 *   <LI>An optional previous DN, which indicates the DN that the entry had
079 *       before the associated operation was processed.  It will only be present
080 *       if the associated operation was a modify DN operation.</LI>
081 *   <LI>An optional change number, which may be used to retrieve additional
082 *       information about the associated operation from the server.  This may
083 *       not be available in all directory server implementations.</LI>
084 * </UL>
085 * Note that the entry change notification control should only be included in
086 * search result entries that are associated with a search request that included
087 * the persistent search request control, and only if that persistent search
088 * request control had the {@code returnECs} flag set to {@code true} to
089 * indicate that entry change notification controls should be included in
090 * resulting entries.  Further, the entry change notification control will only
091 * be included in entries that are returned as the result of a change in the
092 * server and not any of the preliminary entries that may be returned if the
093 * corresponding persistent search request had the {@code changesOnly} flag set
094 * to {@code false}.
095 */
096@NotMutable()
097@ThreadSafety(level=ThreadSafetyLevel.COMPLETELY_THREADSAFE)
098public final class EntryChangeNotificationControl
099       extends Control
100       implements DecodeableControl
101{
102  /**
103   * The OID (2.16.840.1.113730.3.4.7) for the entry change notification
104   * control.
105   */
106  public static final String ENTRY_CHANGE_NOTIFICATION_OID =
107       "2.16.840.1.113730.3.4.7";
108
109
110
111  /**
112   * The serial version UID for this serializable class.
113   */
114  private static final long serialVersionUID = -1305357948140939303L;
115
116
117
118  // The change number for the change, if available.
119  private final long changeNumber;
120
121  // The change type for the change.
122  private final PersistentSearchChangeType changeType;
123
124  // The previous DN of the entry, if applicable.
125  private final String previousDN;
126
127
128
129  /**
130   * Creates a new empty control instance that is intended to be used only for
131   * decoding controls via the {@code DecodeableControl} interface.
132   */
133  EntryChangeNotificationControl()
134  {
135    changeNumber = -1;
136    changeType   = null;
137    previousDN   = null;
138  }
139
140
141
142  /**
143   * Creates a new entry change notification control with the provided
144   * information.  It will not be critical.
145   *
146   * @param  changeType    The change type for the change.  It must not be
147   *                       {@code null}.
148   * @param  previousDN    The previous DN of the entry, if applicable.
149   * @param  changeNumber  The change number to include in this control, or
150   *                       -1 if there should not be a change number.
151   */
152  public EntryChangeNotificationControl(
153              final PersistentSearchChangeType changeType,
154              final String previousDN, final long changeNumber)
155  {
156    this(changeType, previousDN, changeNumber, false);
157  }
158
159
160
161  /**
162   * Creates a new entry change notification control with the provided
163   * information.
164   *
165   * @param  changeType    The change type for the change.  It must not be
166   *                       {@code null}.
167   * @param  previousDN    The previous DN of the entry, if applicable.
168   * @param  changeNumber  The change number to include in this control, or
169   *                       -1 if there should not be a change number.
170   * @param  isCritical    Indicates whether this control should be marked
171   *                       critical.  Response controls should generally not be
172   *                       critical.
173   */
174  public EntryChangeNotificationControl(
175              final PersistentSearchChangeType changeType,
176              final String previousDN, final long changeNumber,
177              final boolean isCritical)
178  {
179    super(ENTRY_CHANGE_NOTIFICATION_OID, isCritical,
180          encodeValue(changeType, previousDN, changeNumber));
181
182    this.changeType   = changeType;
183    this.previousDN   = previousDN;
184    this.changeNumber = changeNumber;
185  }
186
187
188
189  /**
190   * Creates a new entry change notification control with the provided
191   * information.
192   *
193   * @param  oid         The OID for the control.
194   * @param  isCritical  Indicates whether the control should be marked
195   *                     critical.
196   * @param  value       The encoded value for the control.  This may be
197   *                     {@code null} if no value was provided.
198   *
199   * @throws  LDAPException  If the provided control cannot be decoded as an
200   *                         entry change notification control.
201   */
202  public EntryChangeNotificationControl(final String oid,
203                                        final boolean isCritical,
204                                        final ASN1OctetString value)
205         throws LDAPException
206  {
207    super(oid, isCritical, value);
208
209    if (value == null)
210    {
211      throw new LDAPException(ResultCode.DECODING_ERROR,
212                              ERR_ECN_NO_VALUE.get());
213    }
214
215    final ASN1Sequence ecnSequence;
216    try
217    {
218      final ASN1Element element = ASN1Element.decode(value.getValue());
219      ecnSequence = ASN1Sequence.decodeAsSequence(element);
220    }
221    catch (final ASN1Exception ae)
222    {
223      Debug.debugException(ae);
224      throw new LDAPException(ResultCode.DECODING_ERROR,
225                              ERR_ECN_VALUE_NOT_SEQUENCE.get(ae), ae);
226    }
227
228    final ASN1Element[] ecnElements = ecnSequence.elements();
229    if ((ecnElements.length < 1) || (ecnElements.length > 3))
230    {
231      throw new LDAPException(ResultCode.DECODING_ERROR,
232                              ERR_ECN_INVALID_ELEMENT_COUNT.get(
233                                   ecnElements.length));
234    }
235
236    final ASN1Enumerated ecnEnumerated;
237    try
238    {
239      ecnEnumerated = ASN1Enumerated.decodeAsEnumerated(ecnElements[0]);
240    }
241    catch (final ASN1Exception ae)
242    {
243      Debug.debugException(ae);
244      throw new LDAPException(ResultCode.DECODING_ERROR,
245                              ERR_ECN_FIRST_NOT_ENUMERATED.get(ae), ae);
246    }
247
248    changeType = PersistentSearchChangeType.valueOf(ecnEnumerated.intValue());
249    if (changeType == null)
250    {
251      throw new LDAPException(ResultCode.DECODING_ERROR,
252                              ERR_ECN_INVALID_CHANGE_TYPE.get(
253                                   ecnEnumerated.intValue()));
254    }
255
256
257    String prevDN = null;
258    long   chgNum = -1;
259    for (int i=1; i < ecnElements.length; i++)
260    {
261      switch (ecnElements[i].getType())
262      {
263        case ASN1Constants.UNIVERSAL_OCTET_STRING_TYPE:
264          prevDN = ASN1OctetString.decodeAsOctetString(
265                        ecnElements[i]).stringValue();
266          break;
267
268        case ASN1Constants.UNIVERSAL_INTEGER_TYPE:
269          try
270          {
271            chgNum = ASN1Long.decodeAsLong(ecnElements[i]).longValue();
272          }
273          catch (final ASN1Exception ae)
274          {
275            Debug.debugException(ae);
276            throw new LDAPException(ResultCode.DECODING_ERROR,
277                 ERR_ECN_CANNOT_DECODE_CHANGE_NUMBER.get(ae), ae);
278          }
279          break;
280
281        default:
282          throw new LDAPException(ResultCode.DECODING_ERROR,
283               ERR_ECN_INVALID_ELEMENT_TYPE.get(
284                    StaticUtils.toHex(ecnElements[i].getType())));
285      }
286    }
287
288    previousDN   = prevDN;
289    changeNumber = chgNum;
290  }
291
292
293
294  /**
295   * {@inheritDoc}
296   */
297  @Override()
298  public EntryChangeNotificationControl
299              decodeControl(final String oid, final boolean isCritical,
300                            final ASN1OctetString value)
301         throws LDAPException
302  {
303    return new EntryChangeNotificationControl(oid, isCritical, value);
304  }
305
306
307
308  /**
309   * Extracts an entry change notification control from the provided search
310   * result entry.
311   *
312   * @param  entry  The search result entry from which to retrieve the entry
313   *                change notification control.
314   *
315   * @return  The entry change notification control contained in the provided
316   *          search result entry, or {@code null} if the entry did not contain
317   *          an entry change notification control.
318   *
319   * @throws  LDAPException  If a problem is encountered while attempting to
320   *                         decode the entry change notification control
321   *                         contained in the provided entry.
322   */
323  public static EntryChangeNotificationControl
324                     get(final SearchResultEntry entry)
325         throws LDAPException
326  {
327    final Control c = entry.getControl(ENTRY_CHANGE_NOTIFICATION_OID);
328    if (c == null)
329    {
330      return null;
331    }
332
333    if (c instanceof EntryChangeNotificationControl)
334    {
335      return (EntryChangeNotificationControl) c;
336    }
337    else
338    {
339      return new EntryChangeNotificationControl(c.getOID(), c.isCritical(),
340           c.getValue());
341    }
342  }
343
344
345
346  /**
347   * Encodes the provided information into an octet string that can be used as
348   * the value for this control.
349   *
350   * @param  changeType    The change type for the change.  It must not be
351   *                       {@code null}.
352   * @param  previousDN    The previous DN of the entry, if applicable.
353   * @param  changeNumber  The change number to include in this control, or
354   *                       -1 if there should not be a change number.
355   *
356   * @return  An ASN.1 octet string that can be used as the value for this
357   *          control.
358   */
359  private static ASN1OctetString encodeValue(
360               final PersistentSearchChangeType changeType,
361               final String previousDN, final long changeNumber)
362  {
363    Validator.ensureNotNull(changeType);
364
365    final ArrayList<ASN1Element> elementList = new ArrayList<>(3);
366    elementList.add(new ASN1Enumerated(changeType.intValue()));
367
368    if (previousDN != null)
369    {
370      elementList.add(new ASN1OctetString(previousDN));
371    }
372
373    if (changeNumber > 0)
374    {
375      elementList.add(new ASN1Long(changeNumber));
376    }
377
378    return new ASN1OctetString(new ASN1Sequence(elementList).encode());
379  }
380
381
382
383  /**
384   * Retrieves the change type for this entry change notification control.
385   *
386   * @return  The change type for this entry change notification control.
387   */
388  public PersistentSearchChangeType getChangeType()
389  {
390    return changeType;
391  }
392
393
394
395  /**
396   * Retrieves the previous DN for the entry, if applicable.
397   *
398   * @return  The previous DN for the entry, or {@code null} if there is none.
399   */
400  public String getPreviousDN()
401  {
402    return previousDN;
403  }
404
405
406
407  /**
408   * Retrieves the change number for the associated change, if available.
409   *
410   * @return  The change number for the associated change, or -1 if none was
411   *          provided.
412   */
413  public long getChangeNumber()
414  {
415    return changeNumber;
416  }
417
418
419
420  /**
421   * {@inheritDoc}
422   */
423  @Override()
424  public String getControlName()
425  {
426    return INFO_CONTROL_NAME_ENTRY_CHANGE_NOTIFICATION.get();
427  }
428
429
430
431  /**
432   * {@inheritDoc}
433   */
434  @Override()
435  public void toString(final StringBuilder buffer)
436  {
437    buffer.append("EntryChangeNotificationControl(changeType=");
438    buffer.append(changeType.getName());
439
440    if (previousDN != null)
441    {
442      buffer.append(", previousDN='");
443      buffer.append(previousDN);
444      buffer.append('\'');
445    }
446
447    if (changeNumber > 0)
448    {
449      buffer.append(", changeNumber=");
450      buffer.append(changeNumber);
451    }
452
453    buffer.append(", isCritical=");
454    buffer.append(isCritical());
455    buffer.append(')');
456  }
457}