includes/api/ApiPageSet.php

   1 <?php
   2 /**
   3  *
   4  *
   5  * Created on Sep 24, 2006
   6  *
   7  * Copyright © 2006, 2013 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  22  * http://www.gnu.org/copyleft/gpl.html
  23  *
  24  * @file
  25  */
  26
  27 /**
  28  * This class contains a list of pages that the client has requested.
  29  * Initially, when the client passes in titles=, pageids=, or revisions=
  30  * parameter, an instance of the ApiPageSet class will normalize titles,
  31  * determine if the pages/revisions exist, and prefetch any additional page
  32  * data requested.
  33  *
  34  * When a generator is used, the result of the generator will become the input
  35  * for the second instance of this class, and all subsequent actions will use
  36  * the second instance for all their work.
  37  *
  38  * @ingroup API
  39  * @since 1.21 derives from ApiBase instead of ApiQueryBase
  40  */
  41 class ApiPageSet extends ApiBase {
  42         /**
  43          * Constructor flag: The new instance of ApiPageSet will ignore the 'generator=' parameter
  44          * @since 1.21
  45          */
  46         const DISABLE_GENERATORS = 1;
  47
  48         private $mDbSource;
  49         private $mParams;
  50         private $mResolveRedirects;
  51         private $mConvertTitles;
  52         private $mAllowGenerator;
  53
  54         private $mAllPages = array(); // [ns][dbkey] => page_id or negative when missing
  55         private $mTitles = array();
  56         private $mGoodAndMissingPages = array(); // [ns][dbkey] => page_id or negative when missing
  57         private $mGoodPages = array(); // [ns][dbkey] => page_id
  58         private $mGoodTitles = array();
  59         private $mMissingPages = array(); // [ns][dbkey] => fake page_id
  60         private $mMissingTitles = array();
  61         /** @var array [fake_page_id] => array( 'title' => $title, 'invalidreason' => $reason ) */
  62         private $mInvalidTitles = array();
  63         private $mMissingPageIDs = array();
  64         private $mRedirectTitles = array();
  65         private $mSpecialTitles = array();
  66         private $mNormalizedTitles = array();
  67         private $mInterwikiTitles = array();
  68         /** @var Title[] */
  69         private $mPendingRedirectIDs = array();
  70         private $mResolvedRedirectTitles = array();
  71         private $mConvertedTitles = array();
  72         private $mGoodRevIDs = array();
  73         private $mLiveRevIDs = array();
  74         private $mDeletedRevIDs = array();
  75         private $mMissingRevIDs = array();
  76         private $mGeneratorData = array(); // [ns][dbkey] => data array
  77         private $mFakePageId = -1;
  78         private $mCacheMode = 'public';
  79         private $mRequestedPageFields = array();
  80         /** @var int */
  81         private $mDefaultNamespace = NS_MAIN;
  82         /** @var callable|null */
  83         private $mRedirectMergePolicy;
  84
  85         /**
  86          * Add all items from $values into the result
  87          * @param array $result Output
  88          * @param array $values Values to add
  89          * @param string $flag The name of the boolean flag to mark this element
  90          * @param string $name If given, name of the value
  91          */
  92         private static function addValues( array &$result, $values, $flag = null, $name = null ) {
  93                 foreach ( $values as $val ) {
  94                         if ( $val instanceof Title ) {
  95                                 $v = array();
  96                                 ApiQueryBase::addTitleInfo( $v, $val );
  97                         } elseif ( $name !== null ) {
  98                                 $v = array( $name => $val );
  99                         } else {
 100                                 $v = $val;
 101                         }
 102                         if ( $flag !== null ) {
 103                                 $v[$flag] = true;
 104                         }
 105                         $result[] = $v;
 106                 }
 107         }
 108
 109         /**
 110          * @param ApiBase $dbSource Module implementing getDB().
 111          *        Allows PageSet to reuse existing db connection from the shared state like ApiQuery.
 112          * @param int $flags Zero or more flags like DISABLE_GENERATORS
 113          * @param int $defaultNamespace The namespace to use if none is specified by a prefix.
 114          * @since 1.21 accepts $flags instead of two boolean values
 115          */
 116         public function __construct( ApiBase $dbSource, $flags = 0, $defaultNamespace = NS_MAIN ) {
 117                 parent::__construct( $dbSource->getMain(), $dbSource->getModuleName() );
 118                 $this->mDbSource = $dbSource;
 119                 $this->mAllowGenerator = ( $flags & ApiPageSet::DISABLE_GENERATORS ) == 0;
 120                 $this->mDefaultNamespace = $defaultNamespace;
 121
 122                 $this->mParams = $this->extractRequestParams();
 123                 $this->mResolveRedirects = $this->mParams['redirects'];
 124                 $this->mConvertTitles = $this->mParams['converttitles'];
 125         }
 126
 127         /**
 128          * In case execute() is not called, call this method to mark all relevant parameters as used
 129          * This prevents unused parameters from being reported as warnings
 130          */
 131         public function executeDryRun() {
 132                 $this->executeInternal( true );
 133         }
 134
 135         /**
 136          * Populate the PageSet from the request parameters.
 137          */
 138         public function execute() {
 139                 $this->executeInternal( false );
 140         }
 141
 142         /**
 143          * Populate the PageSet from the request parameters.
 144          * @param bool $isDryRun If true, instantiates generator, but only to mark
 145          *    relevant parameters as used
 146          */
 147         private function executeInternal( $isDryRun ) {
 148                 $generatorName = $this->mAllowGenerator ? $this->mParams['generator'] : null;
 149                 if ( isset( $generatorName ) ) {
 150                         $dbSource = $this->mDbSource;
 151                         if ( !$dbSource instanceof ApiQuery ) {
 152                                 // If the parent container of this pageset is not ApiQuery, we must create it to run generator
 153                                 $dbSource = $this->getMain()->getModuleManager()->getModule( 'query' );
 154                         }
 155                         $generator = $dbSource->getModuleManager()->getModule( $generatorName, null, true );
 156                         if ( $generator === null ) {
 157                                 $this->dieUsage( 'Unknown generator=' . $generatorName, 'badgenerator' );
 158                         }
 159                         if ( !$generator instanceof ApiQueryGeneratorBase ) {
 160                                 $this->dieUsage( "Module $generatorName cannot be used as a generator", 'badgenerator' );
 161                         }
 162                         // Create a temporary pageset to store generator's output,
 163                         // add any additional fields generator may need, and execute pageset to populate titles/pageids
 164                         $tmpPageSet = new ApiPageSet( $dbSource, ApiPageSet::DISABLE_GENERATORS );
 165                         $generator->setGeneratorMode( $tmpPageSet );
 166                         $this->mCacheMode = $generator->getCacheMode( $generator->extractRequestParams() );
 167
 168                         if ( !$isDryRun ) {
 169                                 $generator->requestExtraData( $tmpPageSet );
 170                         }
 171                         $tmpPageSet->executeInternal( $isDryRun );
 172
 173                         // populate this pageset with the generator output
 174                         if ( !$isDryRun ) {
 175                                 $generator->executeGenerator( $this );
 176                                 Hooks::run( 'APIQueryGeneratorAfterExecute', array( &$generator, &$this ) );
 177                         } else {
 178                                 // Prevent warnings from being reported on these parameters
 179                                 $main = $this->getMain();
 180                                 foreach ( $generator->extractRequestParams() as $paramName => $param ) {
 181                                         $main->getVal( $generator->encodeParamName( $paramName ) );
 182                                 }
 183                         }
 184
 185                         if ( !$isDryRun ) {
 186                                 $this->resolvePendingRedirects();
 187                         }
 188                 } else {
 189                         // Only one of the titles/pageids/revids is allowed at the same time
 190                         $dataSource = null;
 191                         if ( isset( $this->mParams['titles'] ) ) {
 192                                 $dataSource = 'titles';
 193                         }
 194                         if ( isset( $this->mParams['pageids'] ) ) {
 195                                 if ( isset( $dataSource ) ) {
 196                                         $this->dieUsage( "Cannot use 'pageids' at the same time as '$dataSource'", 'multisource' );
 197                                 }
 198                                 $dataSource = 'pageids';
 199                         }
 200                         if ( isset( $this->mParams['revids'] ) ) {
 201                                 if ( isset( $dataSource ) ) {
 202                                         $this->dieUsage( "Cannot use 'revids' at the same time as '$dataSource'", 'multisource' );
 203                                 }
 204                                 $dataSource = 'revids';
 205                         }
 206
 207                         if ( !$isDryRun ) {
 208                                 // Populate page information with the original user input
 209                                 switch ( $dataSource ) {
 210                                         case 'titles':
 211                                                 $this->initFromTitles( $this->mParams['titles'] );
 212                                                 break;
 213                                         case 'pageids':
 214                                                 $this->initFromPageIds( $this->mParams['pageids'] );
 215                                                 break;
 216                                         case 'revids':
 217                                                 if ( $this->mResolveRedirects ) {
 218                                                         $this->setWarning( 'Redirect resolution cannot be used ' .
 219                                                                 'together with the revids= parameter. Any redirects ' .
 220                                                                 'the revids= point to have not been resolved.' );
 221                                                 }
 222                                                 $this->mResolveRedirects = false;
 223                                                 $this->initFromRevIDs( $this->mParams['revids'] );
 224                                                 break;
 225                                         default:
 226                                                 // Do nothing - some queries do not need any of the data sources.
 227                                                 break;
 228                                 }
 229                         }
 230                 }
 231         }
 232
 233         /**
 234          * Check whether this PageSet is resolving redirects
 235          * @return bool
 236          */
 237         public function isResolvingRedirects() {
 238                 return $this->mResolveRedirects;
 239         }
 240
 241         /**
 242          * Return the parameter name that is the source of data for this PageSet
 243          *
 244          * If multiple source parameters are specified (e.g. titles and pageids),
 245          * one will be named arbitrarily.
 246          *
 247          * @return string|null
 248          */
 249         public function getDataSource() {
 250                 if ( $this->mAllowGenerator && isset( $this->mParams['generator'] ) ) {
 251                         return 'generator';
 252                 }
 253                 if ( isset( $this->mParams['titles'] ) ) {
 254                         return 'titles';
 255                 }
 256                 if ( isset( $this->mParams['pageids'] ) ) {
 257                         return 'pageids';
 258                 }
 259                 if ( isset( $this->mParams['revids'] ) ) {
 260                         return 'revids';
 261                 }
 262
 263                 return null;
 264         }
 265
 266         /**
 267          * Request an additional field from the page table.
 268          * Must be called before execute()
 269          * @param string $fieldName Field name
 270          */
 271         public function requestField( $fieldName ) {
 272                 $this->mRequestedPageFields[$fieldName] = null;
 273         }
 274
 275         /**
 276          * Get the value of a custom field previously requested through
 277          * requestField()
 278          * @param string $fieldName Field name
 279          * @return mixed Field value
 280          */
 281         public function getCustomField( $fieldName ) {
 282                 return $this->mRequestedPageFields[$fieldName];
 283         }
 284
 285         /**
 286          * Get the fields that have to be queried from the page table:
 287          * the ones requested through requestField() and a few basic ones
 288          * we always need
 289          * @return array Array of field names
 290          */
 291         public function getPageTableFields() {
 292                 // Ensure we get minimum required fields
 293                 // DON'T change this order
 294                 $pageFlds = array(
 295                         'page_namespace' => null,
 296                         'page_title' => null,
 297                         'page_id' => null,
 298                 );
 299
 300                 if ( $this->mResolveRedirects ) {
 301                         $pageFlds['page_is_redirect'] = null;
 302                 }
 303
 304                 if ( $this->getConfig()->get( 'ContentHandlerUseDB' ) ) {
 305                         $pageFlds['page_content_model'] = null;
 306                 }
 307
 308                 // only store non-default fields
 309                 $this->mRequestedPageFields = array_diff_key( $this->mRequestedPageFields, $pageFlds );
 310
 311                 $pageFlds = array_merge( $pageFlds, $this->mRequestedPageFields );
 312
 313                 return array_keys( $pageFlds );
 314         }
 315
 316         /**
 317          * Returns an array [ns][dbkey] => page_id for all requested titles.
 318          * page_id is a unique negative number in case title was not found.
 319          * Invalid titles will also have negative page IDs and will be in namespace 0
 320          * @return array
 321          */
 322         public function getAllTitlesByNamespace() {
 323                 return $this->mAllPages;
 324         }
 325
 326         /**
 327          * All Title objects provided.
 328          * @return Title[]
 329          */
 330         public function getTitles() {
 331                 return $this->mTitles;
 332         }
 333
 334         /**
 335          * Returns the number of unique pages (not revisions) in the set.
 336          * @return int
 337          */
 338         public function getTitleCount() {
 339                 return count( $this->mTitles );
 340         }
 341
 342         /**
 343          * Returns an array [ns][dbkey] => page_id for all good titles.
 344          * @return array
 345          */
 346         public function getGoodTitlesByNamespace() {
 347                 return $this->mGoodPages;
 348         }
 349
 350         /**
 351          * Title objects that were found in the database.
 352          * @return Title[] Array page_id (int) => Title (obj)
 353          */
 354         public function getGoodTitles() {
 355                 return $this->mGoodTitles;
 356         }
 357
 358         /**
 359          * Returns the number of found unique pages (not revisions) in the set.
 360          * @return int
 361          */
 362         public function getGoodTitleCount() {
 363                 return count( $this->mGoodTitles );
 364         }
 365
 366         /**
 367          * Returns an array [ns][dbkey] => fake_page_id for all missing titles.
 368          * fake_page_id is a unique negative number.
 369          * @return array
 370          */
 371         public function getMissingTitlesByNamespace() {
 372                 return $this->mMissingPages;
 373         }
 374
 375         /**
 376          * Title objects that were NOT found in the database.
 377          * The array's index will be negative for each item
 378          * @return Title[]
 379          */
 380         public function getMissingTitles() {
 381                 return $this->mMissingTitles;
 382         }
 383
 384         /**
 385          * Returns an array [ns][dbkey] => page_id for all good and missing titles.
 386          * @return array
 387          */
 388         public function getGoodAndMissingTitlesByNamespace() {
 389                 return $this->mGoodAndMissingPages;
 390         }
 391
 392         /**
 393          * Title objects for good and missing titles.
 394          * @return array
 395          */
 396         public function getGoodAndMissingTitles() {
 397                 return $this->mGoodTitles + $this->mMissingTitles;
 398         }
 399
 400         /**
 401          * Titles that were deemed invalid by Title::newFromText()
 402          * The array's index will be unique and negative for each item
 403          * @deprecated since 1.26, use self::getInvalidTitlesAndReasons()
 404          * @return string[] Array of strings (not Title objects)
 405          */
 406         public function getInvalidTitles() {
 407                 wfDeprecated( __METHOD__, '1.26' );
 408                 return array_map( function ( $t ) {
 409                         return $t['title'];
 410                 }, $this->mInvalidTitles );
 411         }
 412
 413         /**
 414          * Titles that were deemed invalid by Title::newFromText()
 415          * The array's index will be unique and negative for each item
 416          * @return array[] Array of arrays with 'title' and 'invalidreason' properties
 417          */
 418         public function getInvalidTitlesAndReasons() {
 419                 return $this->mInvalidTitles;
 420         }
 421
 422         /**
 423          * Page IDs that were not found in the database
 424          * @return array Array of page IDs
 425          */
 426         public function getMissingPageIDs() {
 427                 return $this->mMissingPageIDs;
 428         }
 429
 430         /**
 431          * Get a list of redirect resolutions - maps a title to its redirect
 432          * target, as an array of output-ready arrays
 433          * @return Title[]
 434          */
 435         public function getRedirectTitles() {
 436                 return $this->mRedirectTitles;
 437         }
 438
 439         /**
 440          * Get a list of redirect resolutions - maps a title to its redirect
 441          * target. Includes generator data for redirect source when available.
 442          * @param ApiResult $result
 443          * @return array Array of prefixed_title (string) => Title object
 444          * @since 1.21
 445          */
 446         public function getRedirectTitlesAsResult( $result = null ) {
 447                 $values = array();
 448                 foreach ( $this->getRedirectTitles() as $titleStrFrom => $titleTo ) {
 449                         $r = array(
 450                                 'from' => strval( $titleStrFrom ),
 451                                 'to' => $titleTo->getPrefixedText(),
 452                         );
 453                         if ( $titleTo->hasFragment() ) {
 454                                 $r['tofragment'] = $titleTo->getFragment();
 455                         }
 456                         if ( $titleTo->isExternal() ) {
 457                                 $r['tointerwiki'] = $titleTo->getInterwiki();
 458                         }
 459                         if ( isset( $this->mResolvedRedirectTitles[$titleStrFrom] ) ) {
 460                                 $titleFrom = $this->mResolvedRedirectTitles[$titleStrFrom];
 461                                 $ns = $titleFrom->getNamespace();
 462                                 $dbkey = $titleFrom->getDBkey();
 463                                 if ( isset( $this->mGeneratorData[$ns][$dbkey] ) ) {
 464                                         $r = array_merge( $this->mGeneratorData[$ns][$dbkey], $r );
 465                                 }
 466                         }
 467
 468                         $values[] = $r;
 469                 }
 470                 if ( !empty( $values ) && $result ) {
 471                         ApiResult::setIndexedTagName( $values, 'r' );
 472                 }
 473
 474                 return $values;
 475         }
 476
 477         /**
 478          * Get a list of title normalizations - maps a title to its normalized
 479          * version.
 480          * @return array Array of raw_prefixed_title (string) => prefixed_title (string)
 481          */
 482         public function getNormalizedTitles() {
 483                 return $this->mNormalizedTitles;
 484         }
 485
 486         /**
 487          * Get a list of title normalizations - maps a title to its normalized
 488          * version in the form of result array.
 489          * @param ApiResult $result
 490          * @return array Array of raw_prefixed_title (string) => prefixed_title (string)
 491          * @since 1.21
 492          */
 493         public function getNormalizedTitlesAsResult( $result = null ) {
 494                 $values = array();
 495                 foreach ( $this->getNormalizedTitles() as $rawTitleStr => $titleStr ) {
 496                         $values[] = array(
 497                                 'from' => $rawTitleStr,
 498                                 'to' => $titleStr
 499                         );
 500                 }
 501                 if ( !empty( $values ) && $result ) {
 502                         ApiResult::setIndexedTagName( $values, 'n' );
 503                 }
 504
 505                 return $values;
 506         }
 507
 508         /**
 509          * Get a list of title conversions - maps a title to its converted
 510          * version.
 511          * @return array Array of raw_prefixed_title (string) => prefixed_title (string)
 512          */
 513         public function getConvertedTitles() {
 514                 return $this->mConvertedTitles;
 515         }
 516
 517         /**
 518          * Get a list of title conversions - maps a title to its converted
 519          * version as a result array.
 520          * @param ApiResult $result
 521          * @return array Array of (from, to) strings
 522          * @since 1.21
 523          */
 524         public function getConvertedTitlesAsResult( $result = null ) {
 525                 $values = array();
 526                 foreach ( $this->getConvertedTitles() as $rawTitleStr => $titleStr ) {
 527                         $values[] = array(
 528                                 'from' => $rawTitleStr,
 529                                 'to' => $titleStr
 530                         );
 531                 }
 532                 if ( !empty( $values ) && $result ) {
 533                         ApiResult::setIndexedTagName( $values, 'c' );
 534                 }
 535
 536                 return $values;
 537         }
 538
 539         /**
 540          * Get a list of interwiki titles - maps a title to its interwiki
 541          * prefix.
 542          * @return array Array of raw_prefixed_title (string) => interwiki_prefix (string)
 543          */
 544         public function getInterwikiTitles() {
 545                 return $this->mInterwikiTitles;
 546         }
 547
 548         /**
 549          * Get a list of interwiki titles - maps a title to its interwiki
 550          * prefix as result.
 551          * @param ApiResult $result
 552          * @param bool $iwUrl
 553          * @return array Array of raw_prefixed_title (string) => interwiki_prefix (string)
 554          * @since 1.21
 555          */
 556         public function getInterwikiTitlesAsResult( $result = null, $iwUrl = false ) {
 557                 $values = array();
 558                 foreach ( $this->getInterwikiTitles() as $rawTitleStr => $interwikiStr ) {
 559                         $item = array(
 560                                 'title' => $rawTitleStr,
 561                                 'iw' => $interwikiStr,
 562                         );
 563                         if ( $iwUrl ) {
 564                                 $title = Title::newFromText( $rawTitleStr );
 565                                 $item['url'] = $title->getFullURL( '', false, PROTO_CURRENT );
 566                         }
 567                         $values[] = $item;
 568                 }
 569                 if ( !empty( $values ) && $result ) {
 570                         ApiResult::setIndexedTagName( $values, 'i' );
 571                 }
 572
 573                 return $values;
 574         }
 575
 576         /**
 577          * Get an array of invalid/special/missing titles.
 578          *
 579          * @param array $invalidChecks List of types of invalid titles to include.
 580          *   Recognized values are:
 581          *   - invalidTitles: Titles and reasons from $this->getInvalidTitlesAndReasons()
 582          *   - special: Titles from $this->getSpecialTitles()
 583          *   - missingIds: ids from $this->getMissingPageIDs()
 584          *   - missingRevIds: ids from $this->getMissingRevisionIDs()
 585          *   - missingTitles: Titles from $this->getMissingTitles()
 586          *   - interwikiTitles: Titles from $this->getInterwikiTitlesAsResult()
 587          * @return array Array suitable for inclusion in the response
 588          * @since 1.23
 589          */
 590         public function getInvalidTitlesAndRevisions( $invalidChecks = array( 'invalidTitles',
 591                 'special', 'missingIds', 'missingRevIds', 'missingTitles', 'interwikiTitles' )
 592         ) {
 593                 $result = array();
 594                 if ( in_array( "invalidTitles", $invalidChecks ) ) {
 595                         self::addValues( $result, $this->getInvalidTitlesAndReasons(), 'invalid' );
 596                 }
 597                 if ( in_array( "special", $invalidChecks ) ) {
 598                         self::addValues( $result, $this->getSpecialTitles(), 'special', 'title' );
 599                 }
 600                 if ( in_array( "missingIds", $invalidChecks ) ) {
 601                         self::addValues( $result, $this->getMissingPageIDs(), 'missing', 'pageid' );
 602                 }
 603                 if ( in_array( "missingRevIds", $invalidChecks ) ) {
 604                         self::addValues( $result, $this->getMissingRevisionIDs(), 'missing', 'revid' );
 605                 }
 606                 if ( in_array( "missingTitles", $invalidChecks ) ) {
 607                         self::addValues( $result, $this->getMissingTitles(), 'missing' );
 608                 }
 609                 if ( in_array( "interwikiTitles", $invalidChecks ) ) {
 610                         self::addValues( $result, $this->getInterwikiTitlesAsResult() );
 611                 }
 612
 613                 return $result;
 614         }
 615
 616         /**
 617          * Get the list of valid revision IDs (requested with the revids= parameter)
 618          * @return array Array of revID (int) => pageID (int)
 619          */
 620         public function getRevisionIDs() {
 621                 return $this->mGoodRevIDs;
 622         }
 623
 624         /**
 625          * Get the list of non-deleted revision IDs (requested with the revids= parameter)
 626          * @return array Array of revID (int) => pageID (int)
 627          */
 628         public function getLiveRevisionIDs() {
 629                 return $this->mLiveRevIDs;
 630         }
 631
 632         /**
 633          * Get the list of revision IDs that were associated with deleted titles.
 634          * @return array Array of revID (int) => pageID (int)
 635          */
 636         public function getDeletedRevisionIDs() {
 637                 return $this->mDeletedRevIDs;
 638         }
 639
 640         /**
 641          * Revision IDs that were not found in the database
 642          * @return array Array of revision IDs
 643          */
 644         public function getMissingRevisionIDs() {
 645                 return $this->mMissingRevIDs;
 646         }
 647
 648         /**
 649          * Revision IDs that were not found in the database as result array.
 650          * @param ApiResult $result
 651          * @return array Array of revision IDs
 652          * @since 1.21
 653          */
 654         public function getMissingRevisionIDsAsResult( $result = null ) {
 655                 $values = array();
 656                 foreach ( $this->getMissingRevisionIDs() as $revid ) {
 657                         $values[$revid] = array(
 658                                 'revid' => $revid
 659                         );
 660                 }
 661                 if ( !empty( $values ) && $result ) {
 662                         ApiResult::setIndexedTagName( $values, 'rev' );
 663                 }
 664
 665                 return $values;
 666         }
 667
 668         /**
 669          * Get the list of titles with negative namespace
 670          * @return Title[]
 671          */
 672         public function getSpecialTitles() {
 673                 return $this->mSpecialTitles;
 674         }
 675
 676         /**
 677          * Returns the number of revisions (requested with revids= parameter).
 678          * @return int Number of revisions.
 679          */
 680         public function getRevisionCount() {
 681                 return count( $this->getRevisionIDs() );
 682         }
 683
 684         /**
 685          * Populate this PageSet from a list of Titles
 686          * @param array $titles Array of Title objects
 687          */
 688         public function populateFromTitles( $titles ) {
 689                 $this->initFromTitles( $titles );
 690         }
 691
 692         /**
 693          * Populate this PageSet from a list of page IDs
 694          * @param array $pageIDs Array of page IDs
 695          */
 696         public function populateFromPageIDs( $pageIDs ) {
 697                 $this->initFromPageIds( $pageIDs );
 698         }
 699
 700         /**
 701          * Populate this PageSet from a rowset returned from the database
 702          *
 703          * Note that the query result must include the columns returned by
 704          * $this->getPageTableFields().
 705          *
 706          * @param IDatabase $db
 707          * @param ResultWrapper $queryResult Query result object
 708          */
 709         public function populateFromQueryResult( $db, $queryResult ) {
 710                 $this->initFromQueryResult( $queryResult );
 711         }
 712
 713         /**
 714          * Populate this PageSet from a list of revision IDs
 715          * @param array $revIDs Array of revision IDs
 716          */
 717         public function populateFromRevisionIDs( $revIDs ) {
 718                 $this->initFromRevIDs( $revIDs );
 719         }
 720
 721         /**
 722          * Extract all requested fields from the row received from the database
 723          * @param stdClass $row Result row
 724          */
 725         public function processDbRow( $row ) {
 726                 // Store Title object in various data structures
 727                 $title = Title::newFromRow( $row );
 728
 729                 $pageId = intval( $row->page_id );
 730                 $this->mAllPages[$row->page_namespace][$row->page_title] = $pageId;
 731                 $this->mTitles[] = $title;
 732
 733                 if ( $this->mResolveRedirects && $row->page_is_redirect == '1' ) {
 734                         $this->mPendingRedirectIDs[$pageId] = $title;
 735                 } else {
 736                         $this->mGoodPages[$row->page_namespace][$row->page_title] = $pageId;
 737                         $this->mGoodAndMissingPages[$row->page_namespace][$row->page_title] = $pageId;
 738                         $this->mGoodTitles[$pageId] = $title;
 739                 }
 740
 741                 foreach ( $this->mRequestedPageFields as $fieldName => &$fieldValues ) {
 742                         $fieldValues[$pageId] = $row->$fieldName;
 743                 }
 744         }
 745
 746         /**
 747          * Do not use, does nothing, will be removed
 748          * @deprecated since 1.21
 749          */
 750         public function finishPageSetGeneration() {
 751                 wfDeprecated( __METHOD__, '1.21' );
 752         }
 753
 754         /**
 755          * This method populates internal variables with page information
 756          * based on the given array of title strings.
 757          *
 758          * Steps:
 759          * #1 For each title, get data from `page` table
 760          * #2 If page was not found in the DB, store it as missing
 761          *
 762          * Additionally, when resolving redirects:
 763          * #3 If no more redirects left, stop.
 764          * #4 For each redirect, get its target from the `redirect` table.
 765          * #5 Substitute the original LinkBatch object with the new list
 766          * #6 Repeat from step #1
 767          *
 768          * @param array $titles Array of Title objects or strings
 769          */
 770         private function initFromTitles( $titles ) {
 771                 // Get validated and normalized title objects
 772                 $linkBatch = $this->processTitlesArray( $titles );
 773                 if ( $linkBatch->isEmpty() ) {
 774                         return;
 775                 }
 776
 777                 $db = $this->getDB();
 778                 $set = $linkBatch->constructSet( 'page', $db );
 779
 780                 // Get pageIDs data from the `page` table
 781                 $res = $db->select( 'page', $this->getPageTableFields(), $set,
 782                         __METHOD__ );
 783
 784                 // Hack: get the ns:titles stored in array(ns => array(titles)) format
 785                 $this->initFromQueryResult( $res, $linkBatch->data, true ); // process Titles
 786
 787                 // Resolve any found redirects
 788                 $this->resolvePendingRedirects();
 789         }
 790
 791         /**
 792          * Does the same as initFromTitles(), but is based on page IDs instead
 793          * @param array $pageids Array of page IDs
 794          */
 795         private function initFromPageIds( $pageids ) {
 796                 if ( !$pageids ) {
 797                         return;
 798                 }
 799
 800                 $pageids = array_map( 'intval', $pageids ); // paranoia
 801                 $remaining = array_flip( $pageids );
 802
 803                 $pageids = self::getPositiveIntegers( $pageids );
 804
 805                 $res = null;
 806                 if ( !empty( $pageids ) ) {
 807                         $set = array(
 808                                 'page_id' => $pageids
 809                         );
 810                         $db = $this->getDB();
 811
 812                         // Get pageIDs data from the `page` table
 813                         $res = $db->select( 'page', $this->getPageTableFields(), $set,
 814                                 __METHOD__ );
 815                 }
 816
 817                 $this->initFromQueryResult( $res, $remaining, false ); // process PageIDs
 818
 819                 // Resolve any found redirects
 820                 $this->resolvePendingRedirects();
 821         }
 822
 823         /**
 824          * Iterate through the result of the query on 'page' table,
 825          * and for each row create and store title object and save any extra fields requested.
 826          * @param ResultWrapper $res DB Query result
 827          * @param array $remaining Array of either pageID or ns/title elements (optional).
 828          *        If given, any missing items will go to $mMissingPageIDs and $mMissingTitles
 829          * @param bool $processTitles Must be provided together with $remaining.
 830          *        If true, treat $remaining as an array of [ns][title]
 831          *        If false, treat it as an array of [pageIDs]
 832          */
 833         private function initFromQueryResult( $res, &$remaining = null, $processTitles = null ) {
 834                 if ( !is_null( $remaining ) && is_null( $processTitles ) ) {
 835                         ApiBase::dieDebug( __METHOD__, 'Missing $processTitles parameter when $remaining is provided' );
 836                 }
 837
 838                 $usernames = array();
 839                 if ( $res ) {
 840                         foreach ( $res as $row ) {
 841                                 $pageId = intval( $row->page_id );
 842
 843                                 // Remove found page from the list of remaining items
 844                                 if ( isset( $remaining ) ) {
 845                                         if ( $processTitles ) {
 846                                                 unset( $remaining[$row->page_namespace][$row->page_title] );
 847                                         } else {
 848                                                 unset( $remaining[$pageId] );
 849                                         }
 850                                 }
 851
 852                                 // Store any extra fields requested by modules
 853                                 $this->processDbRow( $row );
 854
 855                                 // Need gender information
 856                                 if ( MWNamespace::hasGenderDistinction( $row->page_namespace ) ) {
 857                                         $usernames[] = $row->page_title;
 858                                 }
 859                         }
 860                 }
 861
 862                 if ( isset( $remaining ) ) {
 863                         // Any items left in the $remaining list are added as missing
 864                         if ( $processTitles ) {
 865                                 // The remaining titles in $remaining are non-existent pages
 866                                 foreach ( $remaining as $ns => $dbkeys ) {
 867                                         foreach ( array_keys( $dbkeys ) as $dbkey ) {
 868                                                 $title = Title::makeTitle( $ns, $dbkey );
 869                                                 $this->mAllPages[$ns][$dbkey] = $this->mFakePageId;
 870                                                 $this->mMissingPages[$ns][$dbkey] = $this->mFakePageId;
 871                                                 $this->mGoodAndMissingPages[$ns][$dbkey] = $this->mFakePageId;
 872                                                 $this->mMissingTitles[$this->mFakePageId] = $title;
 873                                                 $this->mFakePageId--;
 874                                                 $this->mTitles[] = $title;
 875
 876                                                 // need gender information
 877                                                 if ( MWNamespace::hasGenderDistinction( $ns ) ) {
 878                                                         $usernames[] = $dbkey;
 879                                                 }
 880                                         }
 881                                 }
 882                         } else {
 883                                 // The remaining pageids do not exist
 884                                 if ( !$this->mMissingPageIDs ) {
 885                                         $this->mMissingPageIDs = array_keys( $remaining );
 886                                 } else {
 887                                         $this->mMissingPageIDs = array_merge( $this->mMissingPageIDs, array_keys( $remaining ) );
 888                                 }
 889                         }
 890                 }
 891
 892                 // Get gender information
 893                 $genderCache = GenderCache::singleton();
 894                 $genderCache->doQuery( $usernames, __METHOD__ );
 895         }
 896
 897         /**
 898          * Does the same as initFromTitles(), but is based on revision IDs
 899          * instead
 900          * @param array $revids Array of revision IDs
 901          */
 902         private function initFromRevIDs( $revids ) {
 903                 if ( !$revids ) {
 904                         return;
 905                 }
 906
 907                 $revids = array_map( 'intval', $revids ); // paranoia
 908                 $db = $this->getDB();
 909                 $pageids = array();
 910                 $remaining = array_flip( $revids );
 911
 912                 $revids = self::getPositiveIntegers( $revids );
 913
 914                 if ( !empty( $revids ) ) {
 915                         $tables = array( 'revision', 'page' );
 916                         $fields = array( 'rev_id', 'rev_page' );
 917                         $where = array( 'rev_id' => $revids, 'rev_page = page_id' );
 918
 919                         // Get pageIDs data from the `page` table
 920                         $res = $db->select( $tables, $fields, $where, __METHOD__ );
 921                         foreach ( $res as $row ) {
 922                                 $revid = intval( $row->rev_id );
 923                                 $pageid = intval( $row->rev_page );
 924                                 $this->mGoodRevIDs[$revid] = $pageid;
 925                                 $this->mLiveRevIDs[$revid] = $pageid;
 926                                 $pageids[$pageid] = '';
 927                                 unset( $remaining[$revid] );
 928                         }
 929                 }
 930
 931                 $this->mMissingRevIDs = array_keys( $remaining );
 932
 933                 // Populate all the page information
 934                 $this->initFromPageIds( array_keys( $pageids ) );
 935
 936                 // If the user can see deleted revisions, pull out the corresponding
 937                 // titles from the archive table and include them too. We ignore
 938                 // ar_page_id because deleted revisions are tied by title, not page_id.
 939                 if ( !empty( $this->mMissingRevIDs ) && $this->getUser()->isAllowed( 'deletedhistory' ) ) {
 940                         $remaining = array_flip( $this->mMissingRevIDs );
 941                         $tables = array( 'archive' );
 942                         $fields = array( 'ar_rev_id', 'ar_namespace', 'ar_title' );
 943                         $where = array( 'ar_rev_id' => $this->mMissingRevIDs );
 944
 945                         $res = $db->select( $tables, $fields, $where, __METHOD__ );
 946                         $titles = array();
 947                         foreach ( $res as $row ) {
 948                                 $revid = intval( $row->ar_rev_id );
 949                                 $titles[$revid] = Title::makeTitle( $row->ar_namespace, $row->ar_title );
 950                                 unset( $remaining[$revid] );
 951                         }
 952
 953                         $this->initFromTitles( $titles );
 954
 955                         foreach ( $titles as $revid => $title ) {
 956                                 $ns = $title->getNamespace();
 957                                 $dbkey = $title->getDBkey();
 958
 959                                 // Handle converted titles
 960                                 if ( !isset( $this->mAllPages[$ns][$dbkey] ) &&
 961                                         isset( $this->mConvertedTitles[$title->getPrefixedText()] )
 962                                 ) {
 963                                         $title = Title::newFromText( $this->mConvertedTitles[$title->getPrefixedText()] );
 964                                         $ns = $title->getNamespace();
 965                                         $dbkey = $title->getDBkey();
 966                                 }
 967
 968                                 if ( isset( $this->mAllPages[$ns][$dbkey] ) ) {
 969                                         $this->mGoodRevIDs[$revid] = $this->mAllPages[$ns][$dbkey];
 970                                         $this->mDeletedRevIDs[$revid] = $this->mAllPages[$ns][$dbkey];
 971                                 } else {
 972                                         $remaining[$revid] = true;
 973                                 }
 974                         }
 975
 976                         $this->mMissingRevIDs = array_keys( $remaining );
 977                 }
 978         }
 979
 980         /**
 981          * Resolve any redirects in the result if redirect resolution was
 982          * requested. This function is called repeatedly until all redirects
 983          * have been resolved.
 984          */
 985         private function resolvePendingRedirects() {
 986                 if ( $this->mResolveRedirects ) {
 987                         $db = $this->getDB();
 988                         $pageFlds = $this->getPageTableFields();
 989
 990                         // Repeat until all redirects have been resolved
 991                         // The infinite loop is prevented by keeping all known pages in $this->mAllPages
 992                         while ( $this->mPendingRedirectIDs ) {
 993                                 // Resolve redirects by querying the pagelinks table, and repeat the process
 994                                 // Create a new linkBatch object for the next pass
 995                                 $linkBatch = $this->getRedirectTargets();
 996
 997                                 if ( $linkBatch->isEmpty() ) {
 998                                         break;
 999                                 }
1000
1001                                 $set = $linkBatch->constructSet( 'page', $db );
1002                                 if ( $set === false ) {
1003                                         break;
1004                                 }
1005
1006                                 // Get pageIDs data from the `page` table
1007                                 $res = $db->select( 'page', $pageFlds, $set, __METHOD__ );
1008
1009                                 // Hack: get the ns:titles stored in array(ns => array(titles)) format
1010                                 $this->initFromQueryResult( $res, $linkBatch->data, true );
1011                         }
1012                 }
1013         }
1014
1015         /**
1016          * Get the targets of the pending redirects from the database
1017          *
1018          * Also creates entries in the redirect table for redirects that don't
1019          * have one.
1020          * @return LinkBatch
1021          */
1022         private function getRedirectTargets() {
1023                 $lb = new LinkBatch();
1024                 $db = $this->getDB();
1025
1026                 $res = $db->select(
1027                         'redirect',
1028                         array(
1029                                 'rd_from',
1030                                 'rd_namespace',
1031                                 'rd_fragment',
1032                                 'rd_interwiki',
1033                                 'rd_title'
1034                         ), array( 'rd_from' => array_keys( $this->mPendingRedirectIDs ) ),
1035                         __METHOD__
1036                 );
1037                 foreach ( $res as $row ) {
1038                         $rdfrom = intval( $row->rd_from );
1039                         $from = $this->mPendingRedirectIDs[$rdfrom]->getPrefixedText();
1040                         $to = Title::makeTitle(
1041                                 $row->rd_namespace,
1042                                 $row->rd_title,
1043                                 $row->rd_fragment,
1044                                 $row->rd_interwiki
1045                         );
1046                         $this->mResolvedRedirectTitles[$from] = $this->mPendingRedirectIDs[$rdfrom];
1047                         unset( $this->mPendingRedirectIDs[$rdfrom] );
1048                         if ( $to->isExternal() ) {
1049                                 $this->mInterwikiTitles[$to->getPrefixedText()] = $to->getInterwiki();
1050                         } elseif ( !isset( $this->mAllPages[$row->rd_namespace][$row->rd_title] ) ) {
1051                                 $lb->add( $row->rd_namespace, $row->rd_title );
1052                         }
1053                         $this->mRedirectTitles[$from] = $to;
1054                 }
1055
1056                 if ( $this->mPendingRedirectIDs ) {
1057                         // We found pages that aren't in the redirect table
1058                         // Add them
1059                         foreach ( $this->mPendingRedirectIDs as $id => $title ) {
1060                                 $page = WikiPage::factory( $title );
1061                                 $rt = $page->insertRedirect();
1062                                 if ( !$rt ) {
1063                                         // What the hell. Let's just ignore this
1064                                         continue;
1065                                 }
1066                                 $lb->addObj( $rt );
1067                                 $from = $title->getPrefixedText();
1068                                 $this->mResolvedRedirectTitles[$from] = $title;
1069                                 $this->mRedirectTitles[$from] = $rt;
1070                                 unset( $this->mPendingRedirectIDs[$id] );
1071                         }
1072                 }
1073
1074                 return $lb;
1075         }
1076
1077         /**
1078          * Get the cache mode for the data generated by this module.
1079          * All PageSet users should take into account whether this returns a more-restrictive
1080          * cache mode than the using module itself. For possible return values and other
1081          * details about cache modes, see ApiMain::setCacheMode()
1082          *
1083          * Public caching will only be allowed if *all* the modules that supply
1084          * data for a given request return a cache mode of public.
1085          *
1086          * @param array|null $params
1087          * @return string
1088          * @since 1.21
1089          */
1090         public function getCacheMode( $params = null ) {
1091                 return $this->mCacheMode;
1092         }
1093
1094         /**
1095          * Given an array of title strings, convert them into Title objects.
1096          * Alternatively, an array of Title objects may be given.
1097          * This method validates access rights for the title,
1098          * and appends normalization values to the output.
1099          *
1100          * @param array $titles Array of Title objects or strings
1101          * @return LinkBatch
1102          */
1103         private function processTitlesArray( $titles ) {
1104                 $usernames = array();
1105                 $linkBatch = new LinkBatch();
1106
1107                 foreach ( $titles as $title ) {
1108                         if ( is_string( $title ) ) {
1109                                 try {
1110                                         $titleObj = Title::newFromTextThrow( $title, $this->mDefaultNamespace );
1111                                 } catch ( MalformedTitleException $ex ) {
1112                                         // Handle invalid titles gracefully
1113                                         $this->mAllPages[0][$title] = $this->mFakePageId;
1114                                         $this->mInvalidTitles[$this->mFakePageId] = array(
1115                                                 'title' => $title,
1116                                                 'invalidreason' => $ex->getMessage(),
1117                                         );
1118                                         $this->mFakePageId--;
1119                                         continue; // There's nothing else we can do
1120                                 }
1121                         } else {
1122                                 $titleObj = $title;
1123                         }
1124                         $unconvertedTitle = $titleObj->getPrefixedText();
1125                         $titleWasConverted = false;
1126                         if ( $titleObj->isExternal() ) {
1127                                 // This title is an interwiki link.
1128                                 $this->mInterwikiTitles[$unconvertedTitle] = $titleObj->getInterwiki();
1129                         } else {
1130                                 // Variants checking
1131                                 global $wgContLang;
1132                                 if ( $this->mConvertTitles &&
1133                                         count( $wgContLang->getVariants() ) > 1 &&
1134                                         !$titleObj->exists()
1135                                 ) {
1136                                         // Language::findVariantLink will modify titleText and titleObj into
1137                                         // the canonical variant if possible
1138                                         $titleText = is_string( $title ) ? $title : $titleObj->getPrefixedText();
1139                                         $wgContLang->findVariantLink( $titleText, $titleObj );
1140                                         $titleWasConverted = $unconvertedTitle !== $titleObj->getPrefixedText();
1141                                 }
1142
1143                                 if ( $titleObj->getNamespace() < 0 ) {
1144                                         // Handle Special and Media pages
1145                                         $titleObj = $titleObj->fixSpecialName();
1146                                         $this->mSpecialTitles[$this->mFakePageId] = $titleObj;
1147                                         $this->mFakePageId--;
1148                                 } else {
1149                                         // Regular page
1150                                         $linkBatch->addObj( $titleObj );
1151                                 }
1152                         }
1153
1154                         // Make sure we remember the original title that was
1155                         // given to us. This way the caller can correlate new
1156                         // titles with the originally requested when e.g. the
1157                         // namespace is localized or the capitalization is
1158                         // different
1159                         if ( $titleWasConverted ) {
1160                                 $this->mConvertedTitles[$unconvertedTitle] = $titleObj->getPrefixedText();
1161                                 // In this case the page can't be Special.
1162                                 if ( is_string( $title ) && $title !== $unconvertedTitle ) {
1163                                         $this->mNormalizedTitles[$title] = $unconvertedTitle;
1164                                 }
1165                         } elseif ( is_string( $title ) && $title !== $titleObj->getPrefixedText() ) {
1166                                 $this->mNormalizedTitles[$title] = $titleObj->getPrefixedText();
1167                         }
1168
1169                         // Need gender information
1170                         if ( MWNamespace::hasGenderDistinction( $titleObj->getNamespace() ) ) {
1171                                 $usernames[] = $titleObj->getText();
1172                         }
1173                 }
1174                 // Get gender information
1175                 $genderCache = GenderCache::singleton();
1176                 $genderCache->doQuery( $usernames, __METHOD__ );
1177
1178                 return $linkBatch;
1179         }
1180
1181         /**
1182          * Set data for a title.
1183          *
1184          * This data may be extracted into an ApiResult using
1185          * self::populateGeneratorData. This should generally be limited to
1186          * data that is likely to be particularly useful to end users rather than
1187          * just being a dump of everything returned in non-generator mode.
1188          *
1189          * Redirects here will *not* be followed, even if 'redirects' was
1190          * specified, since in the case of multiple redirects we can't know which
1191          * source's data to use on the target.
1192          *
1193          * @param Title $title
1194          * @param array $data
1195          */
1196         public function setGeneratorData( Title $title, array $data ) {
1197                 $ns = $title->getNamespace();
1198                 $dbkey = $title->getDBkey();
1199                 $this->mGeneratorData[$ns][$dbkey] = $data;
1200         }
1201
1202         /**
1203          * Controls how generator data about a redirect source is merged into
1204          * the generator data for the redirect target. When not set no data
1205          * is merged. Note that if multiple titles redirect to the same target
1206          * the order of operations is undefined.
1207          *
1208          * Example to include generated data from redirect in target, prefering
1209          * the data generated for the destination when there is a collision:
1210          * @code
1211          *   $pageSet->setRedirectMergePolicy( function( array $current, array $new ) {
1212          *       return $current + $new;
1213          *   } );
1214          * @endcode
1215          *
1216          * @param callable|null $callable Recieves two array arguments, first the
1217          *  generator data for the redirect target and second the generator data
1218          *  for the redirect source. Returns the resulting generator data to use
1219          *  for the redirect target.
1220          */
1221         public function setRedirectMergePolicy( $callable ) {
1222                 $this->mRedirectMergePolicy = $callable;
1223         }
1224
1225         /**
1226          * Populate the generator data for all titles in the result
1227          *
1228          * The page data may be inserted into an ApiResult object or into an
1229          * associative array. The $path parameter specifies the path within the
1230          * ApiResult or array to find the "pages" node.
1231          *
1232          * The "pages" node itself must be an associative array mapping the page ID
1233          * or fake page ID values returned by this pageset (see
1234          * self::getAllTitlesByNamespace() and self::getSpecialTitles()) to
1235          * associative arrays of page data. Each of those subarrays will have the
1236          * data from self::setGeneratorData() merged in.
1237          *
1238          * Data that was set by self::setGeneratorData() for pages not in the
1239          * "pages" node will be ignored.
1240          *
1241          * @param ApiResult|array &$result
1242          * @param array $path
1243          * @return bool Whether the data fit
1244          */
1245         public function populateGeneratorData( &$result, array $path = array() ) {
1246                 if ( $result instanceof ApiResult ) {
1247                         $data = $result->getResultData( $path );
1248                         if ( $data === null ) {
1249                                 return true;
1250                         }
1251                 } else {
1252                         $data = &$result;
1253                         foreach ( $path as $key ) {
1254                                 if ( !isset( $data[$key] ) ) {
1255                                         // Path isn't in $result, so nothing to add, so everything
1256                                         // "fits"
1257                                         return true;
1258                                 }
1259                                 $data = &$data[$key];
1260                         }
1261                 }
1262                 foreach ( $this->mGeneratorData as $ns => $dbkeys ) {
1263                         if ( $ns === -1 ) {
1264                                 $pages = array();
1265                                 foreach ( $this->mSpecialTitles as $id => $title ) {
1266                                         $pages[$title->getDBkey()] = $id;
1267                                 }
1268                         } else {
1269                                 if ( !isset( $this->mAllPages[$ns] ) ) {
1270                                         // No known titles in the whole namespace. Skip it.
1271                                         continue;
1272                                 }
1273                                 $pages = $this->mAllPages[$ns];
1274                         }
1275                         foreach ( $dbkeys as $dbkey => $genData ) {
1276                                 if ( !isset( $pages[$dbkey] ) ) {
1277                                         // Unknown title. Forget it.
1278                                         continue;
1279                                 }
1280                                 $pageId = $pages[$dbkey];
1281                                 if ( !isset( $data[$pageId] ) ) {
1282                                         // $pageId didn't make it into the result. Ignore it.
1283                                         continue;
1284                                 }
1285
1286                                 if ( $result instanceof ApiResult ) {
1287                                         $path2 = array_merge( $path, array( $pageId ) );
1288                                         foreach ( $genData as $key => $value ) {
1289                                                 if ( !$result->addValue( $path2, $key, $value ) ) {
1290                                                         return false;
1291                                                 }
1292                                         }
1293                                 } else {
1294                                         $data[$pageId] = array_merge( $data[$pageId], $genData );
1295                                 }
1296                         }
1297                 }
1298
1299                 // Merge data generated about redirect titles into the redirect destination
1300                 if ( $this->mRedirectMergePolicy ) {
1301                         foreach ( $this->mResolvedRedirectTitles as $titleFrom ) {
1302                                 $dest = $titleFrom;
1303                                 while ( isset( $this->mRedirectTitles[$dest->getPrefixedText()] ) ) {
1304                                         $dest = $this->mRedirectTitles[$dest->getPrefixedText()];
1305                                 }
1306                                 $fromNs = $titleFrom->getNamespace();
1307                                 $fromDBkey = $titleFrom->getDBkey();
1308                                 $toPageId = $dest->getArticleID();
1309                                 if ( isset( $data[$toPageId] ) &&
1310                                         isset( $this->mGeneratorData[$fromNs][$fromDBkey] )
1311                                 ) {
1312                                         // It is necesary to set both $data and add to $result, if an ApiResult,
1313                                         // to ensure multiple redirects to the same destination are all merged.
1314                                         $data[$toPageId] = call_user_func(
1315                                                 $this->mRedirectMergePolicy,
1316                                                 $data[$toPageId],
1317                                                 $this->mGeneratorData[$fromNs][$fromDBkey]
1318                                         );
1319                                         if ( $result instanceof ApiResult ) {
1320                                                 if ( !$result->addValue( $path, $toPageId, $data[$toPageId], ApiResult::OVERRIDE ) ) {
1321                                                         return false;
1322                                                 }
1323                                         }
1324                                 }
1325                         }
1326                 }
1327
1328                 return true;
1329         }
1330
1331         /**
1332          * Get the database connection (read-only)
1333          * @return DatabaseBase
1334          */
1335         protected function getDB() {
1336                 return $this->mDbSource->getDB();
1337         }
1338
1339         /**
1340          * Returns the input array of integers with all values < 0 removed
1341          *
1342          * @param array $array
1343          * @return array
1344          */
1345         private static function getPositiveIntegers( $array ) {
1346                 // bug 25734 API: possible issue with revids validation
1347                 // It seems with a load of revision rows, MySQL gets upset
1348                 // Remove any < 0 integers, as they can't be valid
1349                 foreach ( $array as $i => $int ) {
1350                         if ( $int < 0 ) {
1351                                 unset( $array[$i] );
1352                         }
1353                 }
1354
1355                 return $array;
1356         }
1357
1358         public function getAllowedParams( $flags = 0 ) {
1359                 $result = array(
1360                         'titles' => array(
1361                                 ApiBase::PARAM_ISMULTI => true,
1362                                 ApiBase::PARAM_HELP_MSG => 'api-pageset-param-titles',
1363                         ),
1364                         'pageids' => array(
1365                                 ApiBase::PARAM_TYPE => 'integer',
1366                                 ApiBase::PARAM_ISMULTI => true,
1367                                 ApiBase::PARAM_HELP_MSG => 'api-pageset-param-pageids',
1368                         ),
1369                         'revids' => array(
1370                                 ApiBase::PARAM_TYPE => 'integer',
1371                                 ApiBase::PARAM_ISMULTI => true,
1372                                 ApiBase::PARAM_HELP_MSG => 'api-pageset-param-revids',
1373                         ),
1374                         'generator' => array(
1375                                 ApiBase::PARAM_TYPE => null,
1376                                 ApiBase::PARAM_HELP_MSG => 'api-pageset-param-generator',
1377                                 ApiBase::PARAM_SUBMODULE_PARAM_PREFIX => 'g',
1378                         ),
1379                         'redirects' => array(
1380                                 ApiBase::PARAM_DFLT => false,
1381                                 ApiBase::PARAM_HELP_MSG => $this->mAllowGenerator
1382                                         ? 'api-pageset-param-redirects-generator'
1383                                         : 'api-pageset-param-redirects-nogenerator',
1384                         ),
1385                         'converttitles' => array(
1386                                 ApiBase::PARAM_DFLT => false,
1387                                 ApiBase::PARAM_HELP_MSG => array(
1388                                         'api-pageset-param-converttitles',
1389                                         new DeferredStringifier(
1390                                                 function ( IContextSource $context ) {
1391                                                         return $context->getLanguage()
1392                                                                 ->commaList( LanguageConverter::$languagesWithVariants );
1393                                                 },
1394                                                 $this
1395                                         )
1396                                 ),
1397                         ),
1398                 );
1399
1400                 if ( !$this->mAllowGenerator ) {
1401                         unset( $result['generator'] );
1402                 } elseif ( $flags & ApiBase::GET_VALUES_FOR_HELP ) {
1403                         $result['generator'][ApiBase::PARAM_TYPE] = 'submodule';
1404                         $result['generator'][ApiBase::PARAM_SUBMODULE_MAP] = $this->getGenerators();
1405                 }
1406
1407                 return $result;
1408         }
1409
1410         private static $generators = null;
1411
1412         /**
1413          * Get an array of all available generators
1414          * @return array
1415          */
1416         private function getGenerators() {
1417                 if ( self::$generators === null ) {
1418                         $query = $this->mDbSource;
1419                         if ( !( $query instanceof ApiQuery ) ) {
1420                                 // If the parent container of this pageset is not ApiQuery,
1421                                 // we must create it to get module manager
1422                                 $query = $this->getMain()->getModuleManager()->getModule( 'query' );
1423                         }
1424                         $gens = array();
1425                         $prefix = $query->getModulePath() . '+';
1426                         $mgr = $query->getModuleManager();
1427                         foreach ( $mgr->getNamesWithClasses() as $name => $class ) {
1428                                 if ( is_subclass_of( $class, 'ApiQueryGeneratorBase' ) ) {
1429                                         $gens[$name] = $prefix . $name;
1430                                 }
1431                         }
1432                         ksort( $gens );
1433                         self::$generators = $gens;
1434                 }
1435
1436                 return self::$generators;
1437         }
1438 }