includes/api/ApiPageSet.php

   1 <?php
   2 /**
   3  * Copyright © 2006, 2013 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22 use MediaWiki\MediaWikiServices;
  23 use Wikimedia\Rdbms\ResultWrapper;
  24 use Wikimedia\Rdbms\IDatabase;
  25
  26 /**
  27  * This class contains a list of pages that the client has requested.
  28  * Initially, when the client passes in titles=, pageids=, or revisions=
  29  * parameter, an instance of the ApiPageSet class will normalize titles,
  30  * determine if the pages/revisions exist, and prefetch any additional page
  31  * data requested.
  32  *
  33  * When a generator is used, the result of the generator will become the input
  34  * for the second instance of this class, and all subsequent actions will use
  35  * the second instance for all their work.
  36  *
  37  * @ingroup API
  38  * @since 1.21 derives from ApiBase instead of ApiQueryBase
  39  */
  40 class ApiPageSet extends ApiBase {
  41         /**
  42          * Constructor flag: The new instance of ApiPageSet will ignore the 'generator=' parameter
  43          * @since 1.21
  44          */
  45         const DISABLE_GENERATORS = 1;
  46
  47         private $mDbSource;
  48         private $mParams;
  49         private $mResolveRedirects;
  50         private $mConvertTitles;
  51         private $mAllowGenerator;
  52
  53         private $mAllPages = []; // [ns][dbkey] => page_id or negative when missing
  54         private $mTitles = [];
  55         private $mGoodAndMissingPages = []; // [ns][dbkey] => page_id or negative when missing
  56         private $mGoodPages = []; // [ns][dbkey] => page_id
  57         private $mGoodTitles = [];
  58         private $mMissingPages = []; // [ns][dbkey] => fake page_id
  59         private $mMissingTitles = [];
  60         /** @var array [fake_page_id] => [ 'title' => $title, 'invalidreason' => $reason ] */
  61         private $mInvalidTitles = [];
  62         private $mMissingPageIDs = [];
  63         private $mRedirectTitles = [];
  64         private $mSpecialTitles = [];
  65         private $mAllSpecials = []; // separate from mAllPages to avoid breaking getAllTitlesByNamespace()
  66         private $mNormalizedTitles = [];
  67         private $mInterwikiTitles = [];
  68         /** @var Title[] */
  69         private $mPendingRedirectIDs = [];
  70         private $mPendingRedirectSpecialPages = []; // [dbkey] => [ Title $from, Title $to ]
  71         private $mResolvedRedirectTitles = [];
  72         private $mConvertedTitles = [];
  73         private $mGoodRevIDs = [];
  74         private $mLiveRevIDs = [];
  75         private $mDeletedRevIDs = [];
  76         private $mMissingRevIDs = [];
  77         private $mGeneratorData = []; // [ns][dbkey] => data array
  78         private $mFakePageId = -1;
  79         private $mCacheMode = 'public';
  80         private $mRequestedPageFields = [];
  81         /** @var int */
  82         private $mDefaultNamespace = NS_MAIN;
  83         /** @var callable|null */
  84         private $mRedirectMergePolicy;
  85
  86         /**
  87          * Add all items from $values into the result
  88          * @param array $result Output
  89          * @param array $values Values to add
  90          * @param string[] $flags The names of boolean flags to mark this element
  91          * @param string $name If given, name of the value
  92          */
  93         private static function addValues( array &$result, $values, $flags = [], $name = null ) {
  94                 foreach ( $values as $val ) {
  95                         if ( $val instanceof Title ) {
  96                                 $v = [];
  97                                 ApiQueryBase::addTitleInfo( $v, $val );
  98                         } elseif ( $name !== null ) {
  99                                 $v = [ $name => $val ];
 100                         } else {
 101                                 $v = $val;
 102                         }
 103                         foreach ( $flags as $flag ) {
 104                                 $v[$flag] = true;
 105                         }
 106                         $result[] = $v;
 107                 }
 108         }
 109
 110         /**
 111          * @param ApiBase $dbSource Module implementing getDB().
 112          *        Allows PageSet to reuse existing db connection from the shared state like ApiQuery.
 113          * @param int $flags Zero or more flags like DISABLE_GENERATORS
 114          * @param int $defaultNamespace The namespace to use if none is specified by a prefix.
 115          * @since 1.21 accepts $flags instead of two boolean values
 116          */
 117         public function __construct( ApiBase $dbSource, $flags = 0, $defaultNamespace = NS_MAIN ) {
 118                 parent::__construct( $dbSource->getMain(), $dbSource->getModuleName() );
 119                 $this->mDbSource = $dbSource;
 120                 $this->mAllowGenerator = ( $flags & self::DISABLE_GENERATORS ) == 0;
 121                 $this->mDefaultNamespace = $defaultNamespace;
 122
 123                 $this->mParams = $this->extractRequestParams();
 124                 $this->mResolveRedirects = $this->mParams['redirects'];
 125                 $this->mConvertTitles = $this->mParams['converttitles'];
 126         }
 127
 128         /**
 129          * In case execute() is not called, call this method to mark all relevant parameters as used
 130          * This prevents unused parameters from being reported as warnings
 131          */
 132         public function executeDryRun() {
 133                 $this->executeInternal( true );
 134         }
 135
 136         /**
 137          * Populate the PageSet from the request parameters.
 138          */
 139         public function execute() {
 140                 $this->executeInternal( false );
 141         }
 142
 143         /**
 144          * Populate the PageSet from the request parameters.
 145          * @param bool $isDryRun If true, instantiates generator, but only to mark
 146          *    relevant parameters as used
 147          */
 148         private function executeInternal( $isDryRun ) {
 149                 $generatorName = $this->mAllowGenerator ? $this->mParams['generator'] : null;
 150                 if ( isset( $generatorName ) ) {
 151                         $dbSource = $this->mDbSource;
 152                         if ( !$dbSource instanceof ApiQuery ) {
 153                                 // If the parent container of this pageset is not ApiQuery, we must create it to run generator
 154                                 $dbSource = $this->getMain()->getModuleManager()->getModule( 'query' );
 155                         }
 156                         $generator = $dbSource->getModuleManager()->getModule( $generatorName, null, true );
 157                         if ( $generator === null ) {
 158                                 $this->dieWithError( [ 'apierror-badgenerator-unknown', $generatorName ], 'badgenerator' );
 159                         }
 160                         if ( !$generator instanceof ApiQueryGeneratorBase ) {
 161                                 $this->dieWithError( [ 'apierror-badgenerator-notgenerator', $generatorName ], 'badgenerator' );
 162                         }
 163                         // Create a temporary pageset to store generator's output,
 164                         // add any additional fields generator may need, and execute pageset to populate titles/pageids
 165                         $tmpPageSet = new ApiPageSet( $dbSource, self::DISABLE_GENERATORS );
 166                         $generator->setGeneratorMode( $tmpPageSet );
 167                         $this->mCacheMode = $generator->getCacheMode( $generator->extractRequestParams() );
 168
 169                         if ( !$isDryRun ) {
 170                                 $generator->requestExtraData( $tmpPageSet );
 171                         }
 172                         $tmpPageSet->executeInternal( $isDryRun );
 173
 174                         // populate this pageset with the generator output
 175                         if ( !$isDryRun ) {
 176                                 $generator->executeGenerator( $this );
 177
 178                                 // Avoid PHP 7.1 warning of passing $this by reference
 179                                 $apiModule = $this;
 180                                 Hooks::run( 'APIQueryGeneratorAfterExecute', [ &$generator, &$apiModule ] );
 181                         } else {
 182                                 // Prevent warnings from being reported on these parameters
 183                                 $main = $this->getMain();
 184                                 foreach ( $generator->extractRequestParams() as $paramName => $param ) {
 185                                         $main->markParamsUsed( $generator->encodeParamName( $paramName ) );
 186                                 }
 187                         }
 188
 189                         if ( !$isDryRun ) {
 190                                 $this->resolvePendingRedirects();
 191                         }
 192                 } else {
 193                         // Only one of the titles/pageids/revids is allowed at the same time
 194                         $dataSource = null;
 195                         if ( isset( $this->mParams['titles'] ) ) {
 196                                 $dataSource = 'titles';
 197                         }
 198                         if ( isset( $this->mParams['pageids'] ) ) {
 199                                 if ( isset( $dataSource ) ) {
 200                                         $this->dieWithError(
 201                                                 [
 202                                                         'apierror-invalidparammix-cannotusewith',
 203                                                         $this->encodeParamName( 'pageids' ),
 204                                                         $this->encodeParamName( $dataSource )
 205                                                 ],
 206                                                 'multisource'
 207                                         );
 208                                 }
 209                                 $dataSource = 'pageids';
 210                         }
 211                         if ( isset( $this->mParams['revids'] ) ) {
 212                                 if ( isset( $dataSource ) ) {
 213                                         $this->dieWithError(
 214                                                 [
 215                                                         'apierror-invalidparammix-cannotusewith',
 216                                                         $this->encodeParamName( 'revids' ),
 217                                                         $this->encodeParamName( $dataSource )
 218                                                 ],
 219                                                 'multisource'
 220                                         );
 221                                 }
 222                                 $dataSource = 'revids';
 223                         }
 224
 225                         if ( !$isDryRun ) {
 226                                 // Populate page information with the original user input
 227                                 switch ( $dataSource ) {
 228                                         case 'titles':
 229                                                 $this->initFromTitles( $this->mParams['titles'] );
 230                                                 break;
 231                                         case 'pageids':
 232                                                 $this->initFromPageIds( $this->mParams['pageids'] );
 233                                                 break;
 234                                         case 'revids':
 235                                                 if ( $this->mResolveRedirects ) {
 236                                                         $this->addWarning( 'apiwarn-redirectsandrevids' );
 237                                                 }
 238                                                 $this->mResolveRedirects = false;
 239                                                 $this->initFromRevIDs( $this->mParams['revids'] );
 240                                                 break;
 241                                         default:
 242                                                 // Do nothing - some queries do not need any of the data sources.
 243                                                 break;
 244                                 }
 245                         }
 246                 }
 247         }
 248
 249         /**
 250          * Check whether this PageSet is resolving redirects
 251          * @return bool
 252          */
 253         public function isResolvingRedirects() {
 254                 return $this->mResolveRedirects;
 255         }
 256
 257         /**
 258          * Return the parameter name that is the source of data for this PageSet
 259          *
 260          * If multiple source parameters are specified (e.g. titles and pageids),
 261          * one will be named arbitrarily.
 262          *
 263          * @return string|null
 264          */
 265         public function getDataSource() {
 266                 if ( $this->mAllowGenerator && isset( $this->mParams['generator'] ) ) {
 267                         return 'generator';
 268                 }
 269                 if ( isset( $this->mParams['titles'] ) ) {
 270                         return 'titles';
 271                 }
 272                 if ( isset( $this->mParams['pageids'] ) ) {
 273                         return 'pageids';
 274                 }
 275                 if ( isset( $this->mParams['revids'] ) ) {
 276                         return 'revids';
 277                 }
 278
 279                 return null;
 280         }
 281
 282         /**
 283          * Request an additional field from the page table.
 284          * Must be called before execute()
 285          * @param string $fieldName Field name
 286          */
 287         public function requestField( $fieldName ) {
 288                 $this->mRequestedPageFields[$fieldName] = null;
 289         }
 290
 291         /**
 292          * Get the value of a custom field previously requested through
 293          * requestField()
 294          * @param string $fieldName Field name
 295          * @return mixed Field value
 296          */
 297         public function getCustomField( $fieldName ) {
 298                 return $this->mRequestedPageFields[$fieldName];
 299         }
 300
 301         /**
 302          * Get the fields that have to be queried from the page table:
 303          * the ones requested through requestField() and a few basic ones
 304          * we always need
 305          * @return array Array of field names
 306          */
 307         public function getPageTableFields() {
 308                 // Ensure we get minimum required fields
 309                 // DON'T change this order
 310                 $pageFlds = [
 311                         'page_namespace' => null,
 312                         'page_title' => null,
 313                         'page_id' => null,
 314                 ];
 315
 316                 if ( $this->mResolveRedirects ) {
 317                         $pageFlds['page_is_redirect'] = null;
 318                 }
 319
 320                 if ( $this->getConfig()->get( 'ContentHandlerUseDB' ) ) {
 321                         $pageFlds['page_content_model'] = null;
 322                 }
 323
 324                 if ( $this->getConfig()->get( 'PageLanguageUseDB' ) ) {
 325                         $pageFlds['page_lang'] = null;
 326                 }
 327
 328                 foreach ( LinkCache::getSelectFields() as $field ) {
 329                         $pageFlds[$field] = null;
 330                 }
 331
 332                 $pageFlds = array_merge( $pageFlds, $this->mRequestedPageFields );
 333
 334                 return array_keys( $pageFlds );
 335         }
 336
 337         /**
 338          * Returns an array [ns][dbkey] => page_id for all requested titles.
 339          * page_id is a unique negative number in case title was not found.
 340          * Invalid titles will also have negative page IDs and will be in namespace 0
 341          * @return array
 342          */
 343         public function getAllTitlesByNamespace() {
 344                 return $this->mAllPages;
 345         }
 346
 347         /**
 348          * All Title objects provided.
 349          * @return Title[]
 350          */
 351         public function getTitles() {
 352                 return $this->mTitles;
 353         }
 354
 355         /**
 356          * Returns the number of unique pages (not revisions) in the set.
 357          * @return int
 358          */
 359         public function getTitleCount() {
 360                 return count( $this->mTitles );
 361         }
 362
 363         /**
 364          * Returns an array [ns][dbkey] => page_id for all good titles.
 365          * @return array
 366          */
 367         public function getGoodTitlesByNamespace() {
 368                 return $this->mGoodPages;
 369         }
 370
 371         /**
 372          * Title objects that were found in the database.
 373          * @return Title[] Array page_id (int) => Title (obj)
 374          */
 375         public function getGoodTitles() {
 376                 return $this->mGoodTitles;
 377         }
 378
 379         /**
 380          * Returns the number of found unique pages (not revisions) in the set.
 381          * @return int
 382          */
 383         public function getGoodTitleCount() {
 384                 return count( $this->mGoodTitles );
 385         }
 386
 387         /**
 388          * Returns an array [ns][dbkey] => fake_page_id for all missing titles.
 389          * fake_page_id is a unique negative number.
 390          * @return array
 391          */
 392         public function getMissingTitlesByNamespace() {
 393                 return $this->mMissingPages;
 394         }
 395
 396         /**
 397          * Title objects that were NOT found in the database.
 398          * The array's index will be negative for each item
 399          * @return Title[]
 400          */
 401         public function getMissingTitles() {
 402                 return $this->mMissingTitles;
 403         }
 404
 405         /**
 406          * Returns an array [ns][dbkey] => page_id for all good and missing titles.
 407          * @return array
 408          */
 409         public function getGoodAndMissingTitlesByNamespace() {
 410                 return $this->mGoodAndMissingPages;
 411         }
 412
 413         /**
 414          * Title objects for good and missing titles.
 415          * @return array
 416          */
 417         public function getGoodAndMissingTitles() {
 418                 return $this->mGoodTitles + $this->mMissingTitles;
 419         }
 420
 421         /**
 422          * Titles that were deemed invalid by Title::newFromText()
 423          * The array's index will be unique and negative for each item
 424          * @return array[] Array of arrays with 'title' and 'invalidreason' properties
 425          */
 426         public function getInvalidTitlesAndReasons() {
 427                 return $this->mInvalidTitles;
 428         }
 429
 430         /**
 431          * Page IDs that were not found in the database
 432          * @return array Array of page IDs
 433          */
 434         public function getMissingPageIDs() {
 435                 return $this->mMissingPageIDs;
 436         }
 437
 438         /**
 439          * Get a list of redirect resolutions - maps a title to its redirect
 440          * target, as an array of output-ready arrays
 441          * @return Title[]
 442          */
 443         public function getRedirectTitles() {
 444                 return $this->mRedirectTitles;
 445         }
 446
 447         /**
 448          * Get a list of redirect resolutions - maps a title to its redirect
 449          * target. Includes generator data for redirect source when available.
 450          * @param ApiResult|null $result
 451          * @return array Array of prefixed_title (string) => Title object
 452          * @since 1.21
 453          */
 454         public function getRedirectTitlesAsResult( $result = null ) {
 455                 $values = [];
 456                 foreach ( $this->getRedirectTitles() as $titleStrFrom => $titleTo ) {
 457                         $r = [
 458                                 'from' => strval( $titleStrFrom ),
 459                                 'to' => $titleTo->getPrefixedText(),
 460                         ];
 461                         if ( $titleTo->hasFragment() ) {
 462                                 $r['tofragment'] = $titleTo->getFragment();
 463                         }
 464                         if ( $titleTo->isExternal() ) {
 465                                 $r['tointerwiki'] = $titleTo->getInterwiki();
 466                         }
 467                         if ( isset( $this->mResolvedRedirectTitles[$titleStrFrom] ) ) {
 468                                 $titleFrom = $this->mResolvedRedirectTitles[$titleStrFrom];
 469                                 $ns = $titleFrom->getNamespace();
 470                                 $dbkey = $titleFrom->getDBkey();
 471                                 if ( isset( $this->mGeneratorData[$ns][$dbkey] ) ) {
 472                                         $r = array_merge( $this->mGeneratorData[$ns][$dbkey], $r );
 473                                 }
 474                         }
 475
 476                         $values[] = $r;
 477                 }
 478                 if ( !empty( $values ) && $result ) {
 479                         ApiResult::setIndexedTagName( $values, 'r' );
 480                 }
 481
 482                 return $values;
 483         }
 484
 485         /**
 486          * Get a list of title normalizations - maps a title to its normalized
 487          * version.
 488          * @return array Array of raw_prefixed_title (string) => prefixed_title (string)
 489          */
 490         public function getNormalizedTitles() {
 491                 return $this->mNormalizedTitles;
 492         }
 493
 494         /**
 495          * Get a list of title normalizations - maps a title to its normalized
 496          * version in the form of result array.
 497          * @param ApiResult|null $result
 498          * @return array Array of raw_prefixed_title (string) => prefixed_title (string)
 499          * @since 1.21
 500          */
 501         public function getNormalizedTitlesAsResult( $result = null ) {
 502                 $values = [];
 503                 $contLang = MediaWikiServices::getInstance()->getContentLanguage();
 504                 foreach ( $this->getNormalizedTitles() as $rawTitleStr => $titleStr ) {
 505                         $encode = $contLang->normalize( $rawTitleStr ) !== $rawTitleStr;
 506                         $values[] = [
 507                                 'fromencoded' => $encode,
 508                                 'from' => $encode ? rawurlencode( $rawTitleStr ) : $rawTitleStr,
 509                                 'to' => $titleStr
 510                         ];
 511                 }
 512                 if ( !empty( $values ) && $result ) {
 513                         ApiResult::setIndexedTagName( $values, 'n' );
 514                 }
 515
 516                 return $values;
 517         }
 518
 519         /**
 520          * Get a list of title conversions - maps a title to its converted
 521          * version.
 522          * @return array Array of raw_prefixed_title (string) => prefixed_title (string)
 523          */
 524         public function getConvertedTitles() {
 525                 return $this->mConvertedTitles;
 526         }
 527
 528         /**
 529          * Get a list of title conversions - maps a title to its converted
 530          * version as a result array.
 531          * @param ApiResult|null $result
 532          * @return array Array of (from, to) strings
 533          * @since 1.21
 534          */
 535         public function getConvertedTitlesAsResult( $result = null ) {
 536                 $values = [];
 537                 foreach ( $this->getConvertedTitles() as $rawTitleStr => $titleStr ) {
 538                         $values[] = [
 539                                 'from' => $rawTitleStr,
 540                                 'to' => $titleStr
 541                         ];
 542                 }
 543                 if ( !empty( $values ) && $result ) {
 544                         ApiResult::setIndexedTagName( $values, 'c' );
 545                 }
 546
 547                 return $values;
 548         }
 549
 550         /**
 551          * Get a list of interwiki titles - maps a title to its interwiki
 552          * prefix.
 553          * @return array Array of raw_prefixed_title (string) => interwiki_prefix (string)
 554          */
 555         public function getInterwikiTitles() {
 556                 return $this->mInterwikiTitles;
 557         }
 558
 559         /**
 560          * Get a list of interwiki titles - maps a title to its interwiki
 561          * prefix as result.
 562          * @param ApiResult|null $result
 563          * @param bool $iwUrl
 564          * @return array Array of raw_prefixed_title (string) => interwiki_prefix (string)
 565          * @since 1.21
 566          */
 567         public function getInterwikiTitlesAsResult( $result = null, $iwUrl = false ) {
 568                 $values = [];
 569                 foreach ( $this->getInterwikiTitles() as $rawTitleStr => $interwikiStr ) {
 570                         $item = [
 571                                 'title' => $rawTitleStr,
 572                                 'iw' => $interwikiStr,
 573                         ];
 574                         if ( $iwUrl ) {
 575                                 $title = Title::newFromText( $rawTitleStr );
 576                                 $item['url'] = $title->getFullURL( '', false, PROTO_CURRENT );
 577                         }
 578                         $values[] = $item;
 579                 }
 580                 if ( !empty( $values ) && $result ) {
 581                         ApiResult::setIndexedTagName( $values, 'i' );
 582                 }
 583
 584                 return $values;
 585         }
 586
 587         /**
 588          * Get an array of invalid/special/missing titles.
 589          *
 590          * @param array $invalidChecks List of types of invalid titles to include.
 591          *   Recognized values are:
 592          *   - invalidTitles: Titles and reasons from $this->getInvalidTitlesAndReasons()
 593          *   - special: Titles from $this->getSpecialTitles()
 594          *   - missingIds: ids from $this->getMissingPageIDs()
 595          *   - missingRevIds: ids from $this->getMissingRevisionIDs()
 596          *   - missingTitles: Titles from $this->getMissingTitles()
 597          *   - interwikiTitles: Titles from $this->getInterwikiTitlesAsResult()
 598          * @return array Array suitable for inclusion in the response
 599          * @since 1.23
 600          */
 601         public function getInvalidTitlesAndRevisions( $invalidChecks = [ 'invalidTitles',
 602                 'special', 'missingIds', 'missingRevIds', 'missingTitles', 'interwikiTitles' ]
 603         ) {
 604                 $result = [];
 605                 if ( in_array( 'invalidTitles', $invalidChecks ) ) {
 606                         self::addValues( $result, $this->getInvalidTitlesAndReasons(), [ 'invalid' ] );
 607                 }
 608                 if ( in_array( 'special', $invalidChecks ) ) {
 609                         $known = [];
 610                         $unknown = [];
 611                         foreach ( $this->getSpecialTitles() as $title ) {
 612                                 if ( $title->isKnown() ) {
 613                                         $known[] = $title;
 614                                 } else {
 615                                         $unknown[] = $title;
 616                                 }
 617                         }
 618                         self::addValues( $result, $unknown, [ 'special', 'missing' ] );
 619                         self::addValues( $result, $known, [ 'special' ] );
 620                 }
 621                 if ( in_array( 'missingIds', $invalidChecks ) ) {
 622                         self::addValues( $result, $this->getMissingPageIDs(), [ 'missing' ], 'pageid' );
 623                 }
 624                 if ( in_array( 'missingRevIds', $invalidChecks ) ) {
 625                         self::addValues( $result, $this->getMissingRevisionIDs(), [ 'missing' ], 'revid' );
 626                 }
 627                 if ( in_array( 'missingTitles', $invalidChecks ) ) {
 628                         $known = [];
 629                         $unknown = [];
 630                         foreach ( $this->getMissingTitles() as $title ) {
 631                                 if ( $title->isKnown() ) {
 632                                         $known[] = $title;
 633                                 } else {
 634                                         $unknown[] = $title;
 635                                 }
 636                         }
 637                         self::addValues( $result, $unknown, [ 'missing' ] );
 638                         self::addValues( $result, $known, [ 'missing', 'known' ] );
 639                 }
 640                 if ( in_array( 'interwikiTitles', $invalidChecks ) ) {
 641                         self::addValues( $result, $this->getInterwikiTitlesAsResult() );
 642                 }
 643
 644                 return $result;
 645         }
 646
 647         /**
 648          * Get the list of valid revision IDs (requested with the revids= parameter)
 649          * @return array Array of revID (int) => pageID (int)
 650          */
 651         public function getRevisionIDs() {
 652                 return $this->mGoodRevIDs;
 653         }
 654
 655         /**
 656          * Get the list of non-deleted revision IDs (requested with the revids= parameter)
 657          * @return array Array of revID (int) => pageID (int)
 658          */
 659         public function getLiveRevisionIDs() {
 660                 return $this->mLiveRevIDs;
 661         }
 662
 663         /**
 664          * Get the list of revision IDs that were associated with deleted titles.
 665          * @return array Array of revID (int) => pageID (int)
 666          */
 667         public function getDeletedRevisionIDs() {
 668                 return $this->mDeletedRevIDs;
 669         }
 670
 671         /**
 672          * Revision IDs that were not found in the database
 673          * @return array Array of revision IDs
 674          */
 675         public function getMissingRevisionIDs() {
 676                 return $this->mMissingRevIDs;
 677         }
 678
 679         /**
 680          * Revision IDs that were not found in the database as result array.
 681          * @param ApiResult|null $result
 682          * @return array Array of revision IDs
 683          * @since 1.21
 684          */
 685         public function getMissingRevisionIDsAsResult( $result = null ) {
 686                 $values = [];
 687                 foreach ( $this->getMissingRevisionIDs() as $revid ) {
 688                         $values[$revid] = [
 689                                 'revid' => $revid
 690                         ];
 691                 }
 692                 if ( !empty( $values ) && $result ) {
 693                         ApiResult::setIndexedTagName( $values, 'rev' );
 694                 }
 695
 696                 return $values;
 697         }
 698
 699         /**
 700          * Get the list of titles with negative namespace
 701          * @return Title[]
 702          */
 703         public function getSpecialTitles() {
 704                 return $this->mSpecialTitles;
 705         }
 706
 707         /**
 708          * Returns the number of revisions (requested with revids= parameter).
 709          * @return int Number of revisions.
 710          */
 711         public function getRevisionCount() {
 712                 return count( $this->getRevisionIDs() );
 713         }
 714
 715         /**
 716          * Populate this PageSet from a list of Titles
 717          * @param array $titles Array of Title objects
 718          */
 719         public function populateFromTitles( $titles ) {
 720                 $this->initFromTitles( $titles );
 721         }
 722
 723         /**
 724          * Populate this PageSet from a list of page IDs
 725          * @param array $pageIDs Array of page IDs
 726          */
 727         public function populateFromPageIDs( $pageIDs ) {
 728                 $this->initFromPageIds( $pageIDs );
 729         }
 730
 731         /**
 732          * Populate this PageSet from a rowset returned from the database
 733          *
 734          * Note that the query result must include the columns returned by
 735          * $this->getPageTableFields().
 736          *
 737          * @param IDatabase $db
 738          * @param ResultWrapper $queryResult
 739          */
 740         public function populateFromQueryResult( $db, $queryResult ) {
 741                 $this->initFromQueryResult( $queryResult );
 742         }
 743
 744         /**
 745          * Populate this PageSet from a list of revision IDs
 746          * @param array $revIDs Array of revision IDs
 747          */
 748         public function populateFromRevisionIDs( $revIDs ) {
 749                 $this->initFromRevIDs( $revIDs );
 750         }
 751
 752         /**
 753          * Extract all requested fields from the row received from the database
 754          * @param stdClass $row Result row
 755          */
 756         public function processDbRow( $row ) {
 757                 // Store Title object in various data structures
 758                 $title = Title::newFromRow( $row );
 759
 760                 $linkCache = MediaWikiServices::getInstance()->getLinkCache();
 761                 $linkCache->addGoodLinkObjFromRow( $title, $row );
 762
 763                 $pageId = intval( $row->page_id );
 764                 $this->mAllPages[$row->page_namespace][$row->page_title] = $pageId;
 765                 $this->mTitles[] = $title;
 766
 767                 if ( $this->mResolveRedirects && $row->page_is_redirect == '1' ) {
 768                         $this->mPendingRedirectIDs[$pageId] = $title;
 769                 } else {
 770                         $this->mGoodPages[$row->page_namespace][$row->page_title] = $pageId;
 771                         $this->mGoodAndMissingPages[$row->page_namespace][$row->page_title] = $pageId;
 772                         $this->mGoodTitles[$pageId] = $title;
 773                 }
 774
 775                 foreach ( $this->mRequestedPageFields as $fieldName => &$fieldValues ) {
 776                         $fieldValues[$pageId] = $row->$fieldName;
 777                 }
 778         }
 779
 780         /**
 781          * This method populates internal variables with page information
 782          * based on the given array of title strings.
 783          *
 784          * Steps:
 785          * #1 For each title, get data from `page` table
 786          * #2 If page was not found in the DB, store it as missing
 787          *
 788          * Additionally, when resolving redirects:
 789          * #3 If no more redirects left, stop.
 790          * #4 For each redirect, get its target from the `redirect` table.
 791          * #5 Substitute the original LinkBatch object with the new list
 792          * #6 Repeat from step #1
 793          *
 794          * @param array $titles Array of Title objects or strings
 795          */
 796         private function initFromTitles( $titles ) {
 797                 // Get validated and normalized title objects
 798                 $linkBatch = $this->processTitlesArray( $titles );
 799                 if ( $linkBatch->isEmpty() ) {
 800                         // There might be special-page redirects
 801                         $this->resolvePendingRedirects();
 802                         return;
 803                 }
 804
 805                 $db = $this->getDB();
 806                 $set = $linkBatch->constructSet( 'page', $db );
 807
 808                 // Get pageIDs data from the `page` table
 809                 $res = $db->select( 'page', $this->getPageTableFields(), $set,
 810                         __METHOD__ );
 811
 812                 // Hack: get the ns:titles stored in [ ns => [ titles ] ] format
 813                 $this->initFromQueryResult( $res, $linkBatch->data, true ); // process Titles
 814
 815                 // Resolve any found redirects
 816                 $this->resolvePendingRedirects();
 817         }
 818
 819         /**
 820          * Does the same as initFromTitles(), but is based on page IDs instead
 821          * @param array $pageids Array of page IDs
 822          */
 823         private function initFromPageIds( $pageids ) {
 824                 if ( !$pageids ) {
 825                         return;
 826                 }
 827
 828                 $pageids = array_map( 'intval', $pageids ); // paranoia
 829                 $remaining = array_flip( $pageids );
 830
 831                 $pageids = self::getPositiveIntegers( $pageids );
 832
 833                 $res = null;
 834                 if ( !empty( $pageids ) ) {
 835                         $set = [
 836                                 'page_id' => $pageids
 837                         ];
 838                         $db = $this->getDB();
 839
 840                         // Get pageIDs data from the `page` table
 841                         $res = $db->select( 'page', $this->getPageTableFields(), $set,
 842                                 __METHOD__ );
 843                 }
 844
 845                 $this->initFromQueryResult( $res, $remaining, false ); // process PageIDs
 846
 847                 // Resolve any found redirects
 848                 $this->resolvePendingRedirects();
 849         }
 850
 851         /**
 852          * Iterate through the result of the query on 'page' table,
 853          * and for each row create and store title object and save any extra fields requested.
 854          * @param ResultWrapper $res DB Query result
 855          * @param array $remaining Array of either pageID or ns/title elements (optional).
 856          *        If given, any missing items will go to $mMissingPageIDs and $mMissingTitles
 857          * @param bool $processTitles Must be provided together with $remaining.
 858          *        If true, treat $remaining as an array of [ns][title]
 859          *        If false, treat it as an array of [pageIDs]
 860          */
 861         private function initFromQueryResult( $res, &$remaining = null, $processTitles = null ) {
 862                 if ( !is_null( $remaining ) && is_null( $processTitles ) ) {
 863                         ApiBase::dieDebug( __METHOD__, 'Missing $processTitles parameter when $remaining is provided' );
 864                 }
 865
 866                 $usernames = [];
 867                 if ( $res ) {
 868                         foreach ( $res as $row ) {
 869                                 $pageId = intval( $row->page_id );
 870
 871                                 // Remove found page from the list of remaining items
 872                                 if ( isset( $remaining ) ) {
 873                                         if ( $processTitles ) {
 874                                                 unset( $remaining[$row->page_namespace][$row->page_title] );
 875                                         } else {
 876                                                 unset( $remaining[$pageId] );
 877                                         }
 878                                 }
 879
 880                                 // Store any extra fields requested by modules
 881                                 $this->processDbRow( $row );
 882
 883                                 // Need gender information
 884                                 if ( MWNamespace::hasGenderDistinction( $row->page_namespace ) ) {
 885                                         $usernames[] = $row->page_title;
 886                                 }
 887                         }
 888                 }
 889
 890                 if ( isset( $remaining ) ) {
 891                         // Any items left in the $remaining list are added as missing
 892                         if ( $processTitles ) {
 893                                 // The remaining titles in $remaining are non-existent pages
 894                                 $linkCache = MediaWikiServices::getInstance()->getLinkCache();
 895                                 foreach ( $remaining as $ns => $dbkeys ) {
 896                                         foreach ( array_keys( $dbkeys ) as $dbkey ) {
 897                                                 $title = Title::makeTitle( $ns, $dbkey );
 898                                                 $linkCache->addBadLinkObj( $title );
 899                                                 $this->mAllPages[$ns][$dbkey] = $this->mFakePageId;
 900                                                 $this->mMissingPages[$ns][$dbkey] = $this->mFakePageId;
 901                                                 $this->mGoodAndMissingPages[$ns][$dbkey] = $this->mFakePageId;
 902                                                 $this->mMissingTitles[$this->mFakePageId] = $title;
 903                                                 $this->mFakePageId--;
 904                                                 $this->mTitles[] = $title;
 905
 906                                                 // need gender information
 907                                                 if ( MWNamespace::hasGenderDistinction( $ns ) ) {
 908                                                         $usernames[] = $dbkey;
 909                                                 }
 910                                         }
 911                                 }
 912                         } else {
 913                                 // The remaining pageids do not exist
 914                                 if ( !$this->mMissingPageIDs ) {
 915                                         $this->mMissingPageIDs = array_keys( $remaining );
 916                                 } else {
 917                                         $this->mMissingPageIDs = array_merge( $this->mMissingPageIDs, array_keys( $remaining ) );
 918                                 }
 919                         }
 920                 }
 921
 922                 // Get gender information
 923                 $genderCache = MediaWikiServices::getInstance()->getGenderCache();
 924                 $genderCache->doQuery( $usernames, __METHOD__ );
 925         }
 926
 927         /**
 928          * Does the same as initFromTitles(), but is based on revision IDs
 929          * instead
 930          * @param array $revids Array of revision IDs
 931          */
 932         private function initFromRevIDs( $revids ) {
 933                 if ( !$revids ) {
 934                         return;
 935                 }
 936
 937                 $revids = array_map( 'intval', $revids ); // paranoia
 938                 $db = $this->getDB();
 939                 $pageids = [];
 940                 $remaining = array_flip( $revids );
 941
 942                 $revids = self::getPositiveIntegers( $revids );
 943
 944                 if ( !empty( $revids ) ) {
 945                         $tables = [ 'revision', 'page' ];
 946                         $fields = [ 'rev_id', 'rev_page' ];
 947                         $where = [ 'rev_id' => $revids, 'rev_page = page_id' ];
 948
 949                         // Get pageIDs data from the `page` table
 950                         $res = $db->select( $tables, $fields, $where, __METHOD__ );
 951                         foreach ( $res as $row ) {
 952                                 $revid = intval( $row->rev_id );
 953                                 $pageid = intval( $row->rev_page );
 954                                 $this->mGoodRevIDs[$revid] = $pageid;
 955                                 $this->mLiveRevIDs[$revid] = $pageid;
 956                                 $pageids[$pageid] = '';
 957                                 unset( $remaining[$revid] );
 958                         }
 959                 }
 960
 961                 $this->mMissingRevIDs = array_keys( $remaining );
 962
 963                 // Populate all the page information
 964                 $this->initFromPageIds( array_keys( $pageids ) );
 965
 966                 // If the user can see deleted revisions, pull out the corresponding
 967                 // titles from the archive table and include them too. We ignore
 968                 // ar_page_id because deleted revisions are tied by title, not page_id.
 969                 if ( !empty( $this->mMissingRevIDs ) && $this->getUser()->isAllowed( 'deletedhistory' ) ) {
 970                         $remaining = array_flip( $this->mMissingRevIDs );
 971                         $tables = [ 'archive' ];
 972                         $fields = [ 'ar_rev_id', 'ar_namespace', 'ar_title' ];
 973                         $where = [ 'ar_rev_id' => $this->mMissingRevIDs ];
 974
 975                         $res = $db->select( $tables, $fields, $where, __METHOD__ );
 976                         $titles = [];
 977                         foreach ( $res as $row ) {
 978                                 $revid = intval( $row->ar_rev_id );
 979                                 $titles[$revid] = Title::makeTitle( $row->ar_namespace, $row->ar_title );
 980                                 unset( $remaining[$revid] );
 981                         }
 982
 983                         $this->initFromTitles( $titles );
 984
 985                         foreach ( $titles as $revid => $title ) {
 986                                 $ns = $title->getNamespace();
 987                                 $dbkey = $title->getDBkey();
 988
 989                                 // Handle converted titles
 990                                 if ( !isset( $this->mAllPages[$ns][$dbkey] ) &&
 991                                         isset( $this->mConvertedTitles[$title->getPrefixedText()] )
 992                                 ) {
 993                                         $title = Title::newFromText( $this->mConvertedTitles[$title->getPrefixedText()] );
 994                                         $ns = $title->getNamespace();
 995                                         $dbkey = $title->getDBkey();
 996                                 }
 997
 998                                 if ( isset( $this->mAllPages[$ns][$dbkey] ) ) {
 999                                         $this->mGoodRevIDs[$revid] = $this->mAllPages[$ns][$dbkey];
1000                                         $this->mDeletedRevIDs[$revid] = $this->mAllPages[$ns][$dbkey];
1001                                 } else {
1002                                         $remaining[$revid] = true;
1003                                 }
1004                         }
1005
1006                         $this->mMissingRevIDs = array_keys( $remaining );
1007                 }
1008         }
1009
1010         /**
1011          * Resolve any redirects in the result if redirect resolution was
1012          * requested. This function is called repeatedly until all redirects
1013          * have been resolved.
1014          */
1015         private function resolvePendingRedirects() {
1016                 if ( $this->mResolveRedirects ) {
1017                         $db = $this->getDB();
1018                         $pageFlds = $this->getPageTableFields();
1019
1020                         // Repeat until all redirects have been resolved
1021                         // The infinite loop is prevented by keeping all known pages in $this->mAllPages
1022                         while ( $this->mPendingRedirectIDs || $this->mPendingRedirectSpecialPages ) {
1023                                 // Resolve redirects by querying the pagelinks table, and repeat the process
1024                                 // Create a new linkBatch object for the next pass
1025                                 $linkBatch = $this->getRedirectTargets();
1026
1027                                 if ( $linkBatch->isEmpty() ) {
1028                                         break;
1029                                 }
1030
1031                                 $set = $linkBatch->constructSet( 'page', $db );
1032                                 if ( $set === false ) {
1033                                         break;
1034                                 }
1035
1036                                 // Get pageIDs data from the `page` table
1037                                 $res = $db->select( 'page', $pageFlds, $set, __METHOD__ );
1038
1039                                 // Hack: get the ns:titles stored in [ns => array(titles)] format
1040                                 $this->initFromQueryResult( $res, $linkBatch->data, true );
1041                         }
1042                 }
1043         }
1044
1045         /**
1046          * Get the targets of the pending redirects from the database
1047          *
1048          * Also creates entries in the redirect table for redirects that don't
1049          * have one.
1050          * @return LinkBatch
1051          */
1052         private function getRedirectTargets() {
1053                 $titlesToResolve = [];
1054                 $db = $this->getDB();
1055
1056                 if ( $this->mPendingRedirectIDs ) {
1057                         $res = $db->select(
1058                                 'redirect',
1059                                 [
1060                                         'rd_from',
1061                                         'rd_namespace',
1062                                         'rd_fragment',
1063                                         'rd_interwiki',
1064                                         'rd_title'
1065                                 ], [ 'rd_from' => array_keys( $this->mPendingRedirectIDs ) ],
1066                                         __METHOD__
1067                                 );
1068                         foreach ( $res as $row ) {
1069                                 $rdfrom = intval( $row->rd_from );
1070                                 $from = $this->mPendingRedirectIDs[$rdfrom]->getPrefixedText();
1071                                 $to = Title::makeTitle(
1072                                         $row->rd_namespace,
1073                                         $row->rd_title,
1074                                         $row->rd_fragment,
1075                                         $row->rd_interwiki
1076                                 );
1077                                 $this->mResolvedRedirectTitles[$from] = $this->mPendingRedirectIDs[$rdfrom];
1078                                 unset( $this->mPendingRedirectIDs[$rdfrom] );
1079                                 if ( $to->isExternal() ) {
1080                                         $this->mInterwikiTitles[$to->getPrefixedText()] = $to->getInterwiki();
1081                                 } elseif ( !isset( $this->mAllPages[$to->getNamespace()][$to->getDBkey()] ) ) {
1082                                         $titlesToResolve[] = $to;
1083                                 }
1084                                 $this->mRedirectTitles[$from] = $to;
1085                         }
1086
1087                         if ( $this->mPendingRedirectIDs ) {
1088                                 // We found pages that aren't in the redirect table
1089                                 // Add them
1090                                 foreach ( $this->mPendingRedirectIDs as $id => $title ) {
1091                                         $page = WikiPage::factory( $title );
1092                                         $rt = $page->insertRedirect();
1093                                         if ( !$rt ) {
1094                                                 // What the hell. Let's just ignore this
1095                                                 continue;
1096                                         }
1097                                         if ( $rt->isExternal() ) {
1098                                                 $this->mInterwikiTitles[$rt->getPrefixedText()] = $rt->getInterwiki();
1099                                         } elseif ( !isset( $this->mAllPages[$rt->getNamespace()][$rt->getDBkey()] ) ) {
1100                                                 $titlesToResolve[] = $rt;
1101                                         }
1102                                         $from = $title->getPrefixedText();
1103                                         $this->mResolvedRedirectTitles[$from] = $title;
1104                                         $this->mRedirectTitles[$from] = $rt;
1105                                         unset( $this->mPendingRedirectIDs[$id] );
1106                                 }
1107                         }
1108                 }
1109
1110                 if ( $this->mPendingRedirectSpecialPages ) {
1111                         foreach ( $this->mPendingRedirectSpecialPages as $key => list( $from, $to ) ) {
1112                                 $fromKey = $from->getPrefixedText();
1113                                 $this->mResolvedRedirectTitles[$fromKey] = $from;
1114                                 $this->mRedirectTitles[$fromKey] = $to;
1115                                 if ( $to->isExternal() ) {
1116                                         $this->mInterwikiTitles[$to->getPrefixedText()] = $to->getInterwiki();
1117                                 } elseif ( !isset( $this->mAllPages[$to->getNamespace()][$to->getDBkey()] ) ) {
1118                                         $titlesToResolve[] = $to;
1119                                 }
1120                         }
1121                         $this->mPendingRedirectSpecialPages = [];
1122
1123                         // Set private caching since we don't know what criteria the
1124                         // special pages used to decide on these redirects.
1125                         $this->mCacheMode = 'private';
1126                 }
1127
1128                 return $this->processTitlesArray( $titlesToResolve );
1129         }
1130
1131         /**
1132          * Get the cache mode for the data generated by this module.
1133          * All PageSet users should take into account whether this returns a more-restrictive
1134          * cache mode than the using module itself. For possible return values and other
1135          * details about cache modes, see ApiMain::setCacheMode()
1136          *
1137          * Public caching will only be allowed if *all* the modules that supply
1138          * data for a given request return a cache mode of public.
1139          *
1140          * @param array|null $params
1141          * @return string
1142          * @since 1.21
1143          */
1144         public function getCacheMode( $params = null ) {
1145                 return $this->mCacheMode;
1146         }
1147
1148         /**
1149          * Given an array of title strings, convert them into Title objects.
1150          * Alternatively, an array of Title objects may be given.
1151          * This method validates access rights for the title,
1152          * and appends normalization values to the output.
1153          *
1154          * @param array $titles Array of Title objects or strings
1155          * @return LinkBatch
1156          */
1157         private function processTitlesArray( $titles ) {
1158                 $usernames = [];
1159                 $linkBatch = new LinkBatch();
1160                 $services = MediaWikiServices::getInstance();
1161                 $contLang = $services->getContentLanguage();
1162
1163                 foreach ( $titles as $title ) {
1164                         if ( is_string( $title ) ) {
1165                                 try {
1166                                         $titleObj = Title::newFromTextThrow( $title, $this->mDefaultNamespace );
1167                                 } catch ( MalformedTitleException $ex ) {
1168                                         // Handle invalid titles gracefully
1169                                         if ( !isset( $this->mAllPages[0][$title] ) ) {
1170                                                 $this->mAllPages[0][$title] = $this->mFakePageId;
1171                                                 $this->mInvalidTitles[$this->mFakePageId] = [
1172                                                         'title' => $title,
1173                                                         'invalidreason' => $this->getErrorFormatter()->formatException( $ex, [ 'bc' => true ] ),
1174                                                 ];
1175                                                 $this->mFakePageId--;
1176                                         }
1177                                         continue; // There's nothing else we can do
1178                                 }
1179                         } else {
1180                                 $titleObj = $title;
1181                         }
1182                         $unconvertedTitle = $titleObj->getPrefixedText();
1183                         $titleWasConverted = false;
1184                         if ( $titleObj->isExternal() ) {
1185                                 // This title is an interwiki link.
1186                                 $this->mInterwikiTitles[$unconvertedTitle] = $titleObj->getInterwiki();
1187                         } else {
1188                                 // Variants checking
1189                                 if (
1190                                         $this->mConvertTitles && $contLang->hasVariants() && !$titleObj->exists()
1191                                 ) {
1192                                         // Language::findVariantLink will modify titleText and titleObj into
1193                                         // the canonical variant if possible
1194                                         $titleText = is_string( $title ) ? $title : $titleObj->getPrefixedText();
1195                                         $contLang->findVariantLink( $titleText, $titleObj );
1196                                         $titleWasConverted = $unconvertedTitle !== $titleObj->getPrefixedText();
1197                                 }
1198
1199                                 if ( $titleObj->getNamespace() < 0 ) {
1200                                         // Handle Special and Media pages
1201                                         $titleObj = $titleObj->fixSpecialName();
1202                                         $ns = $titleObj->getNamespace();
1203                                         $dbkey = $titleObj->getDBkey();
1204                                         if ( !isset( $this->mAllSpecials[$ns][$dbkey] ) ) {
1205                                                 $this->mAllSpecials[$ns][$dbkey] = $this->mFakePageId;
1206                                                 $target = null;
1207                                                 if ( $ns === NS_SPECIAL && $this->mResolveRedirects ) {
1208                                                         $spFactory = $services->getSpecialPageFactory();
1209                                                         $special = $spFactory->getPage( $dbkey );
1210                                                         if ( $special instanceof RedirectSpecialArticle ) {
1211                                                                 // Only RedirectSpecialArticle is intended to redirect to an article, other kinds of
1212                                                                 // RedirectSpecialPage are probably applying weird URL parameters we don't want to handle.
1213                                                                 $context = new DerivativeContext( $this );
1214                                                                 $context->setTitle( $titleObj );
1215                                                                 $context->setRequest( new FauxRequest );
1216                                                                 $special->setContext( $context );
1217                                                                 list( /* $alias */, $subpage ) = $spFactory->resolveAlias( $dbkey );
1218                                                                 $target = $special->getRedirect( $subpage );
1219                                                         }
1220                                                 }
1221                                                 if ( $target ) {
1222                                                         $this->mPendingRedirectSpecialPages[$dbkey] = [ $titleObj, $target ];
1223                                                 } else {
1224                                                         $this->mSpecialTitles[$this->mFakePageId] = $titleObj;
1225                                                         $this->mFakePageId--;
1226                                                 }
1227                                         }
1228                                 } else {
1229                                         // Regular page
1230                                         $linkBatch->addObj( $titleObj );
1231                                 }
1232                         }
1233
1234                         // Make sure we remember the original title that was
1235                         // given to us. This way the caller can correlate new
1236                         // titles with the originally requested when e.g. the
1237                         // namespace is localized or the capitalization is
1238                         // different
1239                         if ( $titleWasConverted ) {
1240                                 $this->mConvertedTitles[$unconvertedTitle] = $titleObj->getPrefixedText();
1241                                 // In this case the page can't be Special.
1242                                 if ( is_string( $title ) && $title !== $unconvertedTitle ) {
1243                                         $this->mNormalizedTitles[$title] = $unconvertedTitle;
1244                                 }
1245                         } elseif ( is_string( $title ) && $title !== $titleObj->getPrefixedText() ) {
1246                                 $this->mNormalizedTitles[$title] = $titleObj->getPrefixedText();
1247                         }
1248
1249                         // Need gender information
1250                         if ( MWNamespace::hasGenderDistinction( $titleObj->getNamespace() ) ) {
1251                                 $usernames[] = $titleObj->getText();
1252                         }
1253                 }
1254                 // Get gender information
1255                 $genderCache = $services->getGenderCache();
1256                 $genderCache->doQuery( $usernames, __METHOD__ );
1257
1258                 return $linkBatch;
1259         }
1260
1261         /**
1262          * Set data for a title.
1263          *
1264          * This data may be extracted into an ApiResult using
1265          * self::populateGeneratorData. This should generally be limited to
1266          * data that is likely to be particularly useful to end users rather than
1267          * just being a dump of everything returned in non-generator mode.
1268          *
1269          * Redirects here will *not* be followed, even if 'redirects' was
1270          * specified, since in the case of multiple redirects we can't know which
1271          * source's data to use on the target.
1272          *
1273          * @param Title $title
1274          * @param array $data
1275          */
1276         public function setGeneratorData( Title $title, array $data ) {
1277                 $ns = $title->getNamespace();
1278                 $dbkey = $title->getDBkey();
1279                 $this->mGeneratorData[$ns][$dbkey] = $data;
1280         }
1281
1282         /**
1283          * Controls how generator data about a redirect source is merged into
1284          * the generator data for the redirect target. When not set no data
1285          * is merged. Note that if multiple titles redirect to the same target
1286          * the order of operations is undefined.
1287          *
1288          * Example to include generated data from redirect in target, prefering
1289          * the data generated for the destination when there is a collision:
1290          * @code
1291          *   $pageSet->setRedirectMergePolicy( function( array $current, array $new ) {
1292          *       return $current + $new;
1293          *   } );
1294          * @endcode
1295          *
1296          * @param callable|null $callable Recieves two array arguments, first the
1297          *  generator data for the redirect target and second the generator data
1298          *  for the redirect source. Returns the resulting generator data to use
1299          *  for the redirect target.
1300          */
1301         public function setRedirectMergePolicy( $callable ) {
1302                 $this->mRedirectMergePolicy = $callable;
1303         }
1304
1305         /**
1306          * Populate the generator data for all titles in the result
1307          *
1308          * The page data may be inserted into an ApiResult object or into an
1309          * associative array. The $path parameter specifies the path within the
1310          * ApiResult or array to find the "pages" node.
1311          *
1312          * The "pages" node itself must be an associative array mapping the page ID
1313          * or fake page ID values returned by this pageset (see
1314          * self::getAllTitlesByNamespace() and self::getSpecialTitles()) to
1315          * associative arrays of page data. Each of those subarrays will have the
1316          * data from self::setGeneratorData() merged in.
1317          *
1318          * Data that was set by self::setGeneratorData() for pages not in the
1319          * "pages" node will be ignored.
1320          *
1321          * @param ApiResult|array &$result
1322          * @param array $path
1323          * @return bool Whether the data fit
1324          */
1325         public function populateGeneratorData( &$result, array $path = [] ) {
1326                 if ( $result instanceof ApiResult ) {
1327                         $data = $result->getResultData( $path );
1328                         if ( $data === null ) {
1329                                 return true;
1330                         }
1331                 } else {
1332                         $data = &$result;
1333                         foreach ( $path as $key ) {
1334                                 if ( !isset( $data[$key] ) ) {
1335                                         // Path isn't in $result, so nothing to add, so everything
1336                                         // "fits"
1337                                         return true;
1338                                 }
1339                                 $data = &$data[$key];
1340                         }
1341                 }
1342                 foreach ( $this->mGeneratorData as $ns => $dbkeys ) {
1343                         if ( $ns === NS_SPECIAL ) {
1344                                 $pages = [];
1345                                 foreach ( $this->mSpecialTitles as $id => $title ) {
1346                                         $pages[$title->getDBkey()] = $id;
1347                                 }
1348                         } else {
1349                                 if ( !isset( $this->mAllPages[$ns] ) ) {
1350                                         // No known titles in the whole namespace. Skip it.
1351                                         continue;
1352                                 }
1353                                 $pages = $this->mAllPages[$ns];
1354                         }
1355                         foreach ( $dbkeys as $dbkey => $genData ) {
1356                                 if ( !isset( $pages[$dbkey] ) ) {
1357                                         // Unknown title. Forget it.
1358                                         continue;
1359                                 }
1360                                 $pageId = $pages[$dbkey];
1361                                 if ( !isset( $data[$pageId] ) ) {
1362                                         // $pageId didn't make it into the result. Ignore it.
1363                                         continue;
1364                                 }
1365
1366                                 if ( $result instanceof ApiResult ) {
1367                                         $path2 = array_merge( $path, [ $pageId ] );
1368                                         foreach ( $genData as $key => $value ) {
1369                                                 if ( !$result->addValue( $path2, $key, $value ) ) {
1370                                                         return false;
1371                                                 }
1372                                         }
1373                                 } else {
1374                                         $data[$pageId] = array_merge( $data[$pageId], $genData );
1375                                 }
1376                         }
1377                 }
1378
1379                 // Merge data generated about redirect titles into the redirect destination
1380                 if ( $this->mRedirectMergePolicy ) {
1381                         foreach ( $this->mResolvedRedirectTitles as $titleFrom ) {
1382                                 $dest = $titleFrom;
1383                                 while ( isset( $this->mRedirectTitles[$dest->getPrefixedText()] ) ) {
1384                                         $dest = $this->mRedirectTitles[$dest->getPrefixedText()];
1385                                 }
1386                                 $fromNs = $titleFrom->getNamespace();
1387                                 $fromDBkey = $titleFrom->getDBkey();
1388                                 $toPageId = $dest->getArticleID();
1389                                 if ( isset( $data[$toPageId] ) &&
1390                                         isset( $this->mGeneratorData[$fromNs][$fromDBkey] )
1391                                 ) {
1392                                         // It is necessary to set both $data and add to $result, if an ApiResult,
1393                                         // to ensure multiple redirects to the same destination are all merged.
1394                                         $data[$toPageId] = call_user_func(
1395                                                 $this->mRedirectMergePolicy,
1396                                                 $data[$toPageId],
1397                                                 $this->mGeneratorData[$fromNs][$fromDBkey]
1398                                         );
1399                                         if ( $result instanceof ApiResult ) {
1400                                                 if ( !$result->addValue( $path, $toPageId, $data[$toPageId], ApiResult::OVERRIDE ) ) {
1401                                                         return false;
1402                                                 }
1403                                         }
1404                                 }
1405                         }
1406                 }
1407
1408                 return true;
1409         }
1410
1411         /**
1412          * Get the database connection (read-only)
1413          * @return IDatabase
1414          */
1415         protected function getDB() {
1416                 return $this->mDbSource->getDB();
1417         }
1418
1419         /**
1420          * Returns the input array of integers with all values < 0 removed
1421          *
1422          * @param array $array
1423          * @return array
1424          */
1425         private static function getPositiveIntegers( $array ) {
1426                 // T27734 API: possible issue with revids validation
1427                 // It seems with a load of revision rows, MySQL gets upset
1428                 // Remove any < 0 integers, as they can't be valid
1429                 foreach ( $array as $i => $int ) {
1430                         if ( $int < 0 ) {
1431                                 unset( $array[$i] );
1432                         }
1433                 }
1434
1435                 return $array;
1436         }
1437
1438         public function getAllowedParams( $flags = 0 ) {
1439                 $result = [
1440                         'titles' => [
1441                                 ApiBase::PARAM_ISMULTI => true,
1442                                 ApiBase::PARAM_HELP_MSG => 'api-pageset-param-titles',
1443                         ],
1444                         'pageids' => [
1445                                 ApiBase::PARAM_TYPE => 'integer',
1446                                 ApiBase::PARAM_ISMULTI => true,
1447                                 ApiBase::PARAM_HELP_MSG => 'api-pageset-param-pageids',
1448                         ],
1449                         'revids' => [
1450                                 ApiBase::PARAM_TYPE => 'integer',
1451                                 ApiBase::PARAM_ISMULTI => true,
1452                                 ApiBase::PARAM_HELP_MSG => 'api-pageset-param-revids',
1453                         ],
1454                         'generator' => [
1455                                 ApiBase::PARAM_TYPE => null,
1456                                 ApiBase::PARAM_HELP_MSG => 'api-pageset-param-generator',
1457                                 ApiBase::PARAM_SUBMODULE_PARAM_PREFIX => 'g',
1458                         ],
1459                         'redirects' => [
1460                                 ApiBase::PARAM_DFLT => false,
1461                                 ApiBase::PARAM_HELP_MSG => $this->mAllowGenerator
1462                                         ? 'api-pageset-param-redirects-generator'
1463                                         : 'api-pageset-param-redirects-nogenerator',
1464                         ],
1465                         'converttitles' => [
1466                                 ApiBase::PARAM_DFLT => false,
1467                                 ApiBase::PARAM_HELP_MSG => [
1468                                         'api-pageset-param-converttitles',
1469                                         [ Message::listParam( LanguageConverter::$languagesWithVariants, 'text' ) ],
1470                                 ],
1471                         ],
1472                 ];
1473
1474                 if ( !$this->mAllowGenerator ) {
1475                         unset( $result['generator'] );
1476                 } elseif ( $flags & ApiBase::GET_VALUES_FOR_HELP ) {
1477                         $result['generator'][ApiBase::PARAM_TYPE] = 'submodule';
1478                         $result['generator'][ApiBase::PARAM_SUBMODULE_MAP] = $this->getGenerators();
1479                 }
1480
1481                 return $result;
1482         }
1483
1484         protected function handleParamNormalization( $paramName, $value, $rawValue ) {
1485                 parent::handleParamNormalization( $paramName, $value, $rawValue );
1486
1487                 if ( $paramName === 'titles' ) {
1488                         // For the 'titles' parameter, we want to split it like ApiBase would
1489                         // and add any changed titles to $this->mNormalizedTitles
1490                         $value = $this->explodeMultiValue( $value, self::LIMIT_SML2 + 1 );
1491                         $l = count( $value );
1492                         $rawValue = $this->explodeMultiValue( $rawValue, $l );
1493                         for ( $i = 0; $i < $l; $i++ ) {
1494                                 if ( $value[$i] !== $rawValue[$i] ) {
1495                                         $this->mNormalizedTitles[$rawValue[$i]] = $value[$i];
1496                                 }
1497                         }
1498                 }
1499         }
1500
1501         private static $generators = null;
1502
1503         /**
1504          * Get an array of all available generators
1505          * @return array
1506          */
1507         private function getGenerators() {
1508                 if ( self::$generators === null ) {
1509                         $query = $this->mDbSource;
1510                         if ( !( $query instanceof ApiQuery ) ) {
1511                                 // If the parent container of this pageset is not ApiQuery,
1512                                 // we must create it to get module manager
1513                                 $query = $this->getMain()->getModuleManager()->getModule( 'query' );
1514                         }
1515                         $gens = [];
1516                         $prefix = $query->getModulePath() . '+';
1517                         $mgr = $query->getModuleManager();
1518                         foreach ( $mgr->getNamesWithClasses() as $name => $class ) {
1519                                 if ( is_subclass_of( $class, ApiQueryGeneratorBase::class ) ) {
1520                                         $gens[$name] = $prefix . $name;
1521                                 }
1522                         }
1523                         ksort( $gens );
1524                         self::$generators = $gens;
1525                 }
1526
1527                 return self::$generators;
1528         }
1529 }