summaryrefslogtreecommitdiff
path: root/includes/api/ApiQueryBase.php
blob: a15754ce1e347a6f20f15cbd7627b7ba5d8995f0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
<?php
/**
 *
 *
 * Created on Sep 7, 2006
 *
 * Copyright © 2006 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

/**
 * This is a base class for all Query modules.
 * It provides some common functionality such as constructing various SQL
 * queries.
 *
 * @ingroup API
 */
abstract class ApiQueryBase extends ApiBase {

	private $mQueryModule, $mDb, $tables, $where, $fields, $options, $join_conds;

	/**
	 * @param ApiQuery $queryModule
	 * @param string $moduleName
	 * @param string $paramPrefix
	 */
	public function __construct( ApiQuery $queryModule, $moduleName, $paramPrefix = '' ) {
		parent::__construct( $queryModule->getMain(), $moduleName, $paramPrefix );
		$this->mQueryModule = $queryModule;
		$this->mDb = null;
		$this->resetQueryParams();
	}

	/************************************************************************//**
	 * @name   Methods to implement
	 * @{
	 */

	/**
	 * Get the cache mode for the data generated by this module. Override
	 * this in the module subclass. For possible return values and other
	 * details about cache modes, see ApiMain::setCacheMode()
	 *
	 * Public caching will only be allowed if *all* the modules that supply
	 * data for a given request return a cache mode of public.
	 *
	 * @param array $params
	 * @return string
	 */
	public function getCacheMode( $params ) {
		return 'private';
	}

	/**
	 * Override this method to request extra fields from the pageSet
	 * using $pageSet->requestField('fieldName')
	 *
	 * Note this only makes sense for 'prop' modules, as 'list' and 'meta'
	 * modules should not be using the pageset.
	 *
	 * @param ApiPageSet $pageSet
	 */
	public function requestExtraData( $pageSet ) {
	}

	/**@}*/

	/************************************************************************//**
	 * @name   Data access
	 * @{
	 */

	/**
	 * Get the main Query module
	 * @return ApiQuery
	 */
	public function getQuery() {
		return $this->mQueryModule;
	}

	/**
	 * @see ApiBase::getParent()
	 */
	public function getParent() {
		return $this->getQuery();
	}

	/**
	 * Get the Query database connection (read-only)
	 * @return DatabaseBase
	 */
	protected function getDB() {
		if ( is_null( $this->mDb ) ) {
			$this->mDb = $this->getQuery()->getDB();
		}

		return $this->mDb;
	}

	/**
	 * Selects the query database connection with the given name.
	 * See ApiQuery::getNamedDB() for more information
	 * @param string $name Name to assign to the database connection
	 * @param int $db One of the DB_* constants
	 * @param array $groups Query groups
	 * @return DatabaseBase
	 */
	public function selectNamedDB( $name, $db, $groups ) {
		$this->mDb = $this->getQuery()->getNamedDB( $name, $db, $groups );
	}

	/**
	 * Get the PageSet object to work on
	 * @return ApiPageSet
	 */
	protected function getPageSet() {
		return $this->getQuery()->getPageSet();
	}

	/**@}*/

	/************************************************************************//**
	 * @name   Querying
	 * @{
	 */

	/**
	 * Blank the internal arrays with query parameters
	 */
	protected function resetQueryParams() {
		$this->tables = array();
		$this->where = array();
		$this->fields = array();
		$this->options = array();
		$this->join_conds = array();
	}

	/**
	 * Add a set of tables to the internal array
	 * @param string|string[] $tables Table name or array of table names
	 * @param string|null $alias Table alias, or null for no alias. Cannot be
	 *  used with multiple tables
	 */
	protected function addTables( $tables, $alias = null ) {
		if ( is_array( $tables ) ) {
			if ( !is_null( $alias ) ) {
				ApiBase::dieDebug( __METHOD__, 'Multiple table aliases not supported' );
			}
			$this->tables = array_merge( $this->tables, $tables );
		} else {
			if ( !is_null( $alias ) ) {
				$this->tables[$alias] = $tables;
			} else {
				$this->tables[] = $tables;
			}
		}
	}

	/**
	 * Add a set of JOIN conditions to the internal array
	 *
	 * JOIN conditions are formatted as array( tablename => array(jointype,
	 * conditions) e.g. array('page' => array('LEFT JOIN',
	 * 'page_id=rev_page')) . conditions may be a string or an
	 * addWhere()-style array
	 * @param array $join_conds JOIN conditions
	 */
	protected function addJoinConds( $join_conds ) {
		if ( !is_array( $join_conds ) ) {
			ApiBase::dieDebug( __METHOD__, 'Join conditions have to be arrays' );
		}
		$this->join_conds = array_merge( $this->join_conds, $join_conds );
	}

	/**
	 * Add a set of fields to select to the internal array
	 * @param array|string $value Field name or array of field names
	 */
	protected function addFields( $value ) {
		if ( is_array( $value ) ) {
			$this->fields = array_merge( $this->fields, $value );
		} else {
			$this->fields[] = $value;
		}
	}

	/**
	 * Same as addFields(), but add the fields only if a condition is met
	 * @param array|string $value See addFields()
	 * @param bool $condition If false, do nothing
	 * @return bool $condition
	 */
	protected function addFieldsIf( $value, $condition ) {
		if ( $condition ) {
			$this->addFields( $value );

			return true;
		}

		return false;
	}

	/**
	 * Add a set of WHERE clauses to the internal array.
	 * Clauses can be formatted as 'foo=bar' or array('foo' => 'bar'),
	 * the latter only works if the value is a constant (i.e. not another field)
	 *
	 * If $value is an empty array, this function does nothing.
	 *
	 * For example, array('foo=bar', 'baz' => 3, 'bla' => 'foo') translates
	 * to "foo=bar AND baz='3' AND bla='foo'"
	 * @param string|array $value
	 */
	protected function addWhere( $value ) {
		if ( is_array( $value ) ) {
			// Sanity check: don't insert empty arrays,
			// Database::makeList() chokes on them
			if ( count( $value ) ) {
				$this->where = array_merge( $this->where, $value );
			}
		} else {
			$this->where[] = $value;
		}
	}

	/**
	 * Same as addWhere(), but add the WHERE clauses only if a condition is met
	 * @param string|array $value
	 * @param bool $condition If false, do nothing
	 * @return bool $condition
	 */
	protected function addWhereIf( $value, $condition ) {
		if ( $condition ) {
			$this->addWhere( $value );

			return true;
		}

		return false;
	}

	/**
	 * Equivalent to addWhere(array($field => $value))
	 * @param string $field Field name
	 * @param string $value Value; ignored if null or empty array;
	 */
	protected function addWhereFld( $field, $value ) {
		// Use count() to its full documented capabilities to simultaneously
		// test for null, empty array or empty countable object
		if ( count( $value ) ) {
			$this->where[$field] = $value;
		}
	}

	/**
	 * Add a WHERE clause corresponding to a range, and an ORDER BY
	 * clause to sort in the right direction
	 * @param string $field Field name
	 * @param string $dir If 'newer', sort in ascending order, otherwise
	 *  sort in descending order
	 * @param string $start Value to start the list at. If $dir == 'newer'
	 *  this is the lower boundary, otherwise it's the upper boundary
	 * @param string $end Value to end the list at. If $dir == 'newer' this
	 *  is the upper boundary, otherwise it's the lower boundary
	 * @param bool $sort If false, don't add an ORDER BY clause
	 */
	protected function addWhereRange( $field, $dir, $start, $end, $sort = true ) {
		$isDirNewer = ( $dir === 'newer' );
		$after = ( $isDirNewer ? '>=' : '<=' );
		$before = ( $isDirNewer ? '<=' : '>=' );
		$db = $this->getDB();

		if ( !is_null( $start ) ) {
			$this->addWhere( $field . $after . $db->addQuotes( $start ) );
		}

		if ( !is_null( $end ) ) {
			$this->addWhere( $field . $before . $db->addQuotes( $end ) );
		}

		if ( $sort ) {
			$order = $field . ( $isDirNewer ? '' : ' DESC' );
			// Append ORDER BY
			$optionOrderBy = isset( $this->options['ORDER BY'] )
				? (array)$this->options['ORDER BY']
				: array();
			$optionOrderBy[] = $order;
			$this->addOption( 'ORDER BY', $optionOrderBy );
		}
	}

	/**
	 * Add a WHERE clause corresponding to a range, similar to addWhereRange,
	 * but converts $start and $end to database timestamps.
	 * @see addWhereRange
	 * @param string $field
	 * @param string $dir
	 * @param string $start
	 * @param string $end
	 * @param bool $sort
	 */
	protected function addTimestampWhereRange( $field, $dir, $start, $end, $sort = true ) {
		$db = $this->getDb();
		$this->addWhereRange( $field, $dir,
			$db->timestampOrNull( $start ), $db->timestampOrNull( $end ), $sort );
	}

	/**
	 * Add an option such as LIMIT or USE INDEX. If an option was set
	 * before, the old value will be overwritten
	 * @param string $name Option name
	 * @param string $value Option value
	 */
	protected function addOption( $name, $value = null ) {
		if ( is_null( $value ) ) {
			$this->options[] = $name;
		} else {
			$this->options[$name] = $value;
		}
	}

	/**
	 * Execute a SELECT query based on the values in the internal arrays
	 * @param string $method Function the query should be attributed to.
	 *  You should usually use __METHOD__ here
	 * @param array $extraQuery Query data to add but not store in the object
	 *  Format is array(
	 *    'tables' => ...,
	 *    'fields' => ...,
	 *    'where' => ...,
	 *    'options' => ...,
	 *    'join_conds' => ...
	 *  )
	 * @return ResultWrapper
	 */
	protected function select( $method, $extraQuery = array() ) {

		$tables = array_merge(
			$this->tables,
			isset( $extraQuery['tables'] ) ? (array)$extraQuery['tables'] : array()
		);
		$fields = array_merge(
			$this->fields,
			isset( $extraQuery['fields'] ) ? (array)$extraQuery['fields'] : array()
		);
		$where = array_merge(
			$this->where,
			isset( $extraQuery['where'] ) ? (array)$extraQuery['where'] : array()
		);
		$options = array_merge(
			$this->options,
			isset( $extraQuery['options'] ) ? (array)$extraQuery['options'] : array()
		);
		$join_conds = array_merge(
			$this->join_conds,
			isset( $extraQuery['join_conds'] ) ? (array)$extraQuery['join_conds'] : array()
		);

		$res = $this->getDB()->select( $tables, $fields, $where, $method, $options, $join_conds );

		return $res;
	}

	/**
	 * @param string $query
	 * @param string $protocol
	 * @return null|string
	 */
	public function prepareUrlQuerySearchString( $query = null, $protocol = null ) {
		$db = $this->getDb();
		if ( !is_null( $query ) || $query != '' ) {
			if ( is_null( $protocol ) ) {
				$protocol = 'http://';
			}

			$likeQuery = LinkFilter::makeLikeArray( $query, $protocol );
			if ( !$likeQuery ) {
				$this->dieUsage( 'Invalid query', 'bad_query' );
			}

			$likeQuery = LinkFilter::keepOneWildcard( $likeQuery );

			return 'el_index ' . $db->buildLike( $likeQuery );
		} elseif ( !is_null( $protocol ) ) {
			return 'el_index ' . $db->buildLike( "$protocol", $db->anyString() );
		}

		return null;
	}

	/**
	 * Filters hidden users (where the user doesn't have the right to view them)
	 * Also adds relevant block information
	 *
	 * @param bool $showBlockInfo
	 * @return void
	 */
	public function showHiddenUsersAddBlockInfo( $showBlockInfo ) {
		$this->addTables( 'ipblocks' );
		$this->addJoinConds( array(
			'ipblocks' => array( 'LEFT JOIN', 'ipb_user=user_id' ),
		) );

		$this->addFields( 'ipb_deleted' );

		if ( $showBlockInfo ) {
			$this->addFields( array( 'ipb_id', 'ipb_by', 'ipb_by_text', 'ipb_reason', 'ipb_expiry', 'ipb_timestamp' ) );
		}

		// Don't show hidden names
		if ( !$this->getUser()->isAllowed( 'hideuser' ) ) {
			$this->addWhere( 'ipb_deleted = 0 OR ipb_deleted IS NULL' );
		}
	}

	/**@}*/

	/************************************************************************//**
	 * @name   Utility methods
	 * @{
	 */

	/**
	 * Add information (title and namespace) about a Title object to a
	 * result array
	 * @param array $arr Result array à la ApiResult
	 * @param Title $title
	 * @param string $prefix Module prefix
	 */
	public static function addTitleInfo( &$arr, $title, $prefix = '' ) {
		$arr[$prefix . 'ns'] = intval( $title->getNamespace() );
		$arr[$prefix . 'title'] = $title->getPrefixedText();
	}

	/**
	 * Add a sub-element under the page element with the given page ID
	 * @param int $pageId Page ID
	 * @param array $data Data array à la ApiResult
	 * @return bool Whether the element fit in the result
	 */
	protected function addPageSubItems( $pageId, $data ) {
		$result = $this->getResult();
		ApiResult::setIndexedTagName( $data, $this->getModulePrefix() );

		return $result->addValue( array( 'query', 'pages', intval( $pageId ) ),
			$this->getModuleName(),
			$data );
	}

	/**
	 * Same as addPageSubItems(), but one element of $data at a time
	 * @param int $pageId Page ID
	 * @param array $item Data array à la ApiResult
	 * @param string $elemname XML element name. If null, getModuleName()
	 *  is used
	 * @return bool Whether the element fit in the result
	 */
	protected function addPageSubItem( $pageId, $item, $elemname = null ) {
		if ( is_null( $elemname ) ) {
			$elemname = $this->getModulePrefix();
		}
		$result = $this->getResult();
		$fit = $result->addValue( array( 'query', 'pages', $pageId,
			$this->getModuleName() ), null, $item );
		if ( !$fit ) {
			return false;
		}
		$result->addIndexedTagName( array( 'query', 'pages', $pageId,
			$this->getModuleName() ), $elemname );

		return true;
	}

	/**
	 * Set a query-continue value
	 * @param string $paramName Parameter name
	 * @param string|array $paramValue Parameter value
	 */
	protected function setContinueEnumParameter( $paramName, $paramValue ) {
		$this->getContinuationManager()->addContinueParam( $this, $paramName, $paramValue );
	}

	/**
	 * Convert an input title or title prefix into a dbkey.
	 *
	 * $namespace should always be specified in order to handle per-namespace
	 * capitalization settings.
	 *
	 * @param string $titlePart Title part
	 * @param int $defaultNamespace Namespace of the title
	 * @return string DBkey (no namespace prefix)
	 */
	public function titlePartToKey( $titlePart, $namespace = NS_MAIN ) {
		$t = Title::makeTitleSafe( $namespace, $titlePart . 'x' );
		if ( !$t || $t->hasFragment() ) {
			// Invalid title (e.g. bad chars) or contained a '#'.
			$this->dieUsageMsg( array( 'invalidtitle', $titlePart ) );
		}
		if ( $namespace != $t->getNamespace() || $t->isExternal() ) {
			// This can happen in two cases. First, if you call titlePartToKey with a title part
			// that looks like a namespace, but with $defaultNamespace = NS_MAIN. It would be very
			// difficult to handle such a case. Such cases cannot exist and are therefore treated
			// as invalid user input. The second case is when somebody specifies a title interwiki
			// prefix.
			$this->dieUsageMsg( array( 'invalidtitle', $titlePart ) );
		}

		return substr( $t->getDbKey(), 0, -1 );
	}

	/**
	 * Gets the personalised direction parameter description
	 *
	 * @param string $p ModulePrefix
	 * @param string $extraDirText Any extra text to be appended on the description
	 * @return array
	 */
	public function getDirectionDescription( $p = '', $extraDirText = '' ) {
		return array(
			"In which direction to enumerate{$extraDirText}",
			" newer          - List oldest first. Note: {$p}start has to be before {$p}end.",
			" older          - List newest first (default). Note: {$p}start has to be later than {$p}end.",
		);
	}

	/**
	 * @param string $hash
	 * @return bool
	 */
	public function validateSha1Hash( $hash ) {
		return preg_match( '/^[a-f0-9]{40}$/', $hash );
	}

	/**
	 * @param string $hash
	 * @return bool
	 */
	public function validateSha1Base36Hash( $hash ) {
		return preg_match( '/^[a-z0-9]{31}$/', $hash );
	}

	/**
	 * Check whether the current user has permission to view revision-deleted
	 * fields.
	 * @return bool
	 */
	public function userCanSeeRevDel() {
		return $this->getUser()->isAllowedAny(
			'deletedhistory',
			'deletedtext',
			'suppressrevision',
			'viewsuppressed'
		);
	}

	/**@}*/

	/************************************************************************//**
	 * @name   Deprecated
	 * @{
	 */

	/**
	 * Estimate the row count for the SELECT query that would be run if we
	 * called select() right now, and check if it's acceptable.
	 * @deprecated since 1.24
	 * @return bool True if acceptable, false otherwise
	 */
	protected function checkRowCount() {
		wfDeprecated( __METHOD__, '1.24' );
		$db = $this->getDB();
		$rowcount = $db->estimateRowCount(
			$this->tables,
			$this->fields,
			$this->where,
			__METHOD__,
			$this->options
		);

		if ( $rowcount > $this->getConfig()->get( 'APIMaxDBRows' ) ) {
			return false;
		}

		return true;
	}

	/**
	 * Convert a title to a DB key
	 * @deprecated since 1.24, past uses of this were always incorrect and should
	 *   have used self::titlePartToKey() instead
	 * @param string $title Page title with spaces
	 * @return string Page title with underscores
	 */
	public function titleToKey( $title ) {
		wfDeprecated( __METHOD__, '1.24' );
		// Don't throw an error if we got an empty string
		if ( trim( $title ) == '' ) {
			return '';
		}
		$t = Title::newFromText( $title );
		if ( !$t ) {
			$this->dieUsageMsg( array( 'invalidtitle', $title ) );
		}

		return $t->getPrefixedDBkey();
	}

	/**
	 * The inverse of titleToKey()
	 * @deprecated since 1.24, unused and probably never needed
	 * @param string $key Page title with underscores
	 * @return string Page title with spaces
	 */
	public function keyToTitle( $key ) {
		wfDeprecated( __METHOD__, '1.24' );
		// Don't throw an error if we got an empty string
		if ( trim( $key ) == '' ) {
			return '';
		}
		$t = Title::newFromDBkey( $key );
		// This really shouldn't happen but we gotta check anyway
		if ( !$t ) {
			$this->dieUsageMsg( array( 'invalidtitle', $key ) );
		}

		return $t->getPrefixedText();
	}

	/**
	 * Inverse of titlePartToKey()
	 * @deprecated since 1.24, unused and probably never needed
	 * @param string $keyPart DBkey, with prefix
	 * @return string Key part with underscores
	 */
	public function keyPartToTitle( $keyPart ) {
		wfDeprecated( __METHOD__, '1.24' );
		return substr( $this->keyToTitle( $keyPart . 'x' ), 0, -1 );
	}

	/**@}*/
}

/**
 * @ingroup API
 */
abstract class ApiQueryGeneratorBase extends ApiQueryBase {

	private $mGeneratorPageSet = null;

	/**
	 * Switch this module to generator mode. By default, generator mode is
	 * switched off and the module acts like a normal query module.
	 * @since 1.21 requires pageset parameter
	 * @param ApiPageSet $generatorPageSet ApiPageSet object that the module will get
	 *        by calling getPageSet() when in generator mode.
	 */
	public function setGeneratorMode( ApiPageSet $generatorPageSet ) {
		if ( $generatorPageSet === null ) {
			ApiBase::dieDebug( __METHOD__, 'Required parameter missing - $generatorPageSet' );
		}
		$this->mGeneratorPageSet = $generatorPageSet;
	}

	/**
	 * Get the PageSet object to work on.
	 * If this module is generator, the pageSet object is different from other module's
	 * @return ApiPageSet
	 */
	protected function getPageSet() {
		if ( $this->mGeneratorPageSet !== null ) {
			return $this->mGeneratorPageSet;
		}

		return parent::getPageSet();
	}

	/**
	 * Overrides ApiBase to prepend 'g' to every generator parameter
	 * @param string $paramName Parameter name
	 * @return string Prefixed parameter name
	 */
	public function encodeParamName( $paramName ) {
		if ( $this->mGeneratorPageSet !== null ) {
			return 'g' . parent::encodeParamName( $paramName );
		} else {
			return parent::encodeParamName( $paramName );
		}
	}

	/**
	 * Overridden to set the generator param if in generator mode
	 * @param string $paramName Parameter name
	 * @param string|array $paramValue Parameter value
	 */
	protected function setContinueEnumParameter( $paramName, $paramValue ) {
		if ( $this->mGeneratorPageSet !== null ) {
			$this->getContinuationManager()->addGeneratorContinueParam( $this, $paramName, $paramValue );
		} else {
			parent::setContinueEnumParameter( $paramName, $paramValue );
		}
	}

	/**
	 * @see ApiBase::getHelpFlags()
	 *
	 * Corresponding messages: api-help-flag-generator
	 */
	protected function getHelpFlags() {
		$flags = parent::getHelpFlags();
		$flags[] = 'generator';
		return $flags;
	}

	/**
	 * Execute this module as a generator
	 * @param ApiPageSet $resultPageSet All output should be appended to this object
	 */
	abstract public function executeGenerator( $resultPageSet );
}