includes/page/WikiPage.php

   1 <?php
   2 /**
   3  * Base representation for a MediaWiki page.
   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
  23 use MediaWiki\Edit\PreparedEdit;
  24 use MediaWiki\Logger\LoggerFactory;
  25 use MediaWiki\MediaWikiServices;
  26 use MediaWiki\Revision\RevisionRenderer;
  27 use MediaWiki\Storage\DerivedPageDataUpdater;
  28 use MediaWiki\Storage\PageUpdater;
  29 use MediaWiki\Storage\RevisionRecord;
  30 use MediaWiki\Storage\RevisionSlotsUpdate;
  31 use MediaWiki\Storage\RevisionStore;
  32 use Wikimedia\Assert\Assert;
  33 use Wikimedia\Rdbms\FakeResultWrapper;
  34 use Wikimedia\Rdbms\IDatabase;
  35 use Wikimedia\Rdbms\LoadBalancer;
  36
  37 /**
  38  * Class representing a MediaWiki article and history.
  39  *
  40  * Some fields are public only for backwards-compatibility. Use accessors.
  41  * In the past, this class was part of Article.php and everything was public.
  42  */
  43 class WikiPage implements Page, IDBAccessObject {
  44         // Constants for $mDataLoadedFrom and related
  45
  46         /**
  47          * @var Title
  48          */
  49         public $mTitle = null;
  50
  51         /**@{{
  52          * @protected
  53          */
  54         public $mDataLoaded = false;         // !< Boolean
  55         public $mIsRedirect = false;         // !< Boolean
  56         public $mLatest = false;             // !< Integer (false means "not loaded")
  57         /**@}}*/
  58
  59         /** @var PreparedEdit Map of cache fields (text, parser output, ect) for a proposed/new edit */
  60         public $mPreparedEdit = false;
  61
  62         /**
  63          * @var int
  64          */
  65         protected $mId = null;
  66
  67         /**
  68          * @var int One of the READ_* constants
  69          */
  70         protected $mDataLoadedFrom = self::READ_NONE;
  71
  72         /**
  73          * @var Title
  74          */
  75         protected $mRedirectTarget = null;
  76
  77         /**
  78          * @var Revision
  79          */
  80         protected $mLastRevision = null;
  81
  82         /**
  83          * @var string Timestamp of the current revision or empty string if not loaded
  84          */
  85         protected $mTimestamp = '';
  86
  87         /**
  88          * @var string
  89          */
  90         protected $mTouched = '19700101000000';
  91
  92         /**
  93          * @var string
  94          */
  95         protected $mLinksUpdated = '19700101000000';
  96
  97         /**
  98          * @var DerivedPageDataUpdater|null
  99          */
 100         private $derivedDataUpdater = null;
 101
 102         /**
 103          * Constructor and clear the article
 104          * @param Title $title Reference to a Title object.
 105          */
 106         public function __construct( Title $title ) {
 107                 $this->mTitle = $title;
 108         }
 109
 110         /**
 111          * Makes sure that the mTitle object is cloned
 112          * to the newly cloned WikiPage.
 113          */
 114         public function __clone() {
 115                 $this->mTitle = clone $this->mTitle;
 116         }
 117
 118         /**
 119          * Create a WikiPage object of the appropriate class for the given title.
 120          *
 121          * @param Title $title
 122          *
 123          * @throws MWException
 124          * @return WikiPage|WikiCategoryPage|WikiFilePage
 125          */
 126         public static function factory( Title $title ) {
 127                 $ns = $title->getNamespace();
 128
 129                 if ( $ns == NS_MEDIA ) {
 130                         throw new MWException( "NS_MEDIA is a virtual namespace; use NS_FILE." );
 131                 } elseif ( $ns < 0 ) {
 132                         throw new MWException( "Invalid or virtual namespace $ns given." );
 133                 }
 134
 135                 $page = null;
 136                 if ( !Hooks::run( 'WikiPageFactory', [ $title, &$page ] ) ) {
 137                         return $page;
 138                 }
 139
 140                 switch ( $ns ) {
 141                         case NS_FILE:
 142                                 $page = new WikiFilePage( $title );
 143                                 break;
 144                         case NS_CATEGORY:
 145                                 $page = new WikiCategoryPage( $title );
 146                                 break;
 147                         default:
 148                                 $page = new WikiPage( $title );
 149                 }
 150
 151                 return $page;
 152         }
 153
 154         /**
 155          * Constructor from a page id
 156          *
 157          * @param int $id Article ID to load
 158          * @param string|int $from One of the following values:
 159          *        - "fromdb" or WikiPage::READ_NORMAL to select from a replica DB
 160          *        - "fromdbmaster" or WikiPage::READ_LATEST to select from the master database
 161          *
 162          * @return WikiPage|null
 163          */
 164         public static function newFromID( $id, $from = 'fromdb' ) {
 165                 // page ids are never 0 or negative, see T63166
 166                 if ( $id < 1 ) {
 167                         return null;
 168                 }
 169
 170                 $from = self::convertSelectType( $from );
 171                 $db = wfGetDB( $from === self::READ_LATEST ? DB_MASTER : DB_REPLICA );
 172                 $pageQuery = self::getQueryInfo();
 173                 $row = $db->selectRow(
 174                         $pageQuery['tables'], $pageQuery['fields'], [ 'page_id' => $id ], __METHOD__,
 175                         [], $pageQuery['joins']
 176                 );
 177                 if ( !$row ) {
 178                         return null;
 179                 }
 180                 return self::newFromRow( $row, $from );
 181         }
 182
 183         /**
 184          * Constructor from a database row
 185          *
 186          * @since 1.20
 187          * @param object $row Database row containing at least fields returned by selectFields().
 188          * @param string|int $from Source of $data:
 189          *        - "fromdb" or WikiPage::READ_NORMAL: from a replica DB
 190          *        - "fromdbmaster" or WikiPage::READ_LATEST: from the master DB
 191          *        - "forupdate" or WikiPage::READ_LOCKING: from the master DB using SELECT FOR UPDATE
 192          * @return WikiPage
 193          */
 194         public static function newFromRow( $row, $from = 'fromdb' ) {
 195                 $page = self::factory( Title::newFromRow( $row ) );
 196                 $page->loadFromRow( $row, $from );
 197                 return $page;
 198         }
 199
 200         /**
 201          * Convert 'fromdb', 'fromdbmaster' and 'forupdate' to READ_* constants.
 202          *
 203          * @param object|string|int $type
 204          * @return mixed
 205          */
 206         protected static function convertSelectType( $type ) {
 207                 switch ( $type ) {
 208                         case 'fromdb':
 209                                 return self::READ_NORMAL;
 210                         case 'fromdbmaster':
 211                                 return self::READ_LATEST;
 212                         case 'forupdate':
 213                                 return self::READ_LOCKING;
 214                         default:
 215                                 // It may already be an integer or whatever else
 216                                 return $type;
 217                 }
 218         }
 219
 220         /**
 221          * @return RevisionStore
 222          */
 223         private function getRevisionStore() {
 224                 return MediaWikiServices::getInstance()->getRevisionStore();
 225         }
 226
 227         /**
 228          * @return RevisionRenderer
 229          */
 230         private function getRevisionRenderer() {
 231                 return MediaWikiServices::getInstance()->getRevisionRenderer();
 232         }
 233
 234         /**
 235          * @return ParserCache
 236          */
 237         private function getParserCache() {
 238                 return MediaWikiServices::getInstance()->getParserCache();
 239         }
 240
 241         /**
 242          * @return LoadBalancer
 243          */
 244         private function getDBLoadBalancer() {
 245                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
 246         }
 247
 248         /**
 249          * @todo Move this UI stuff somewhere else
 250          *
 251          * @see ContentHandler::getActionOverrides
 252          * @return array
 253          */
 254         public function getActionOverrides() {
 255                 return $this->getContentHandler()->getActionOverrides();
 256         }
 257
 258         /**
 259          * Returns the ContentHandler instance to be used to deal with the content of this WikiPage.
 260          *
 261          * Shorthand for ContentHandler::getForModelID( $this->getContentModel() );
 262          *
 263          * @return ContentHandler
 264          *
 265          * @since 1.21
 266          */
 267         public function getContentHandler() {
 268                 return ContentHandler::getForModelID( $this->getContentModel() );
 269         }
 270
 271         /**
 272          * Get the title object of the article
 273          * @return Title Title object of this page
 274          */
 275         public function getTitle() {
 276                 return $this->mTitle;
 277         }
 278
 279         /**
 280          * Clear the object
 281          * @return void
 282          */
 283         public function clear() {
 284                 $this->mDataLoaded = false;
 285                 $this->mDataLoadedFrom = self::READ_NONE;
 286
 287                 $this->clearCacheFields();
 288         }
 289
 290         /**
 291          * Clear the object cache fields
 292          * @return void
 293          */
 294         protected function clearCacheFields() {
 295                 $this->mId = null;
 296                 $this->mRedirectTarget = null; // Title object if set
 297                 $this->mLastRevision = null; // Latest revision
 298                 $this->mTouched = '19700101000000';
 299                 $this->mLinksUpdated = '19700101000000';
 300                 $this->mTimestamp = '';
 301                 $this->mIsRedirect = false;
 302                 $this->mLatest = false;
 303                 // T59026: do not clear $this->derivedDataUpdater since getDerivedDataUpdater() already
 304                 // checks the requested rev ID and content against the cached one. For most
 305                 // content types, the output should not change during the lifetime of this cache.
 306                 // Clearing it can cause extra parses on edit for no reason.
 307         }
 308
 309         /**
 310          * Clear the mPreparedEdit cache field, as may be needed by mutable content types
 311          * @return void
 312          * @since 1.23
 313          */
 314         public function clearPreparedEdit() {
 315                 $this->mPreparedEdit = false;
 316         }
 317
 318         /**
 319          * Return the list of revision fields that should be selected to create
 320          * a new page.
 321          *
 322          * @deprecated since 1.31, use self::getQueryInfo() instead.
 323          * @return array
 324          */
 325         public static function selectFields() {
 326                 global $wgContentHandlerUseDB, $wgPageLanguageUseDB;
 327
 328                 wfDeprecated( __METHOD__, '1.31' );
 329
 330                 $fields = [
 331                         'page_id',
 332                         'page_namespace',
 333                         'page_title',
 334                         'page_restrictions',
 335                         'page_is_redirect',
 336                         'page_is_new',
 337                         'page_random',
 338                         'page_touched',
 339                         'page_links_updated',
 340                         'page_latest',
 341                         'page_len',
 342                 ];
 343
 344                 if ( $wgContentHandlerUseDB ) {
 345                         $fields[] = 'page_content_model';
 346                 }
 347
 348                 if ( $wgPageLanguageUseDB ) {
 349                         $fields[] = 'page_lang';
 350                 }
 351
 352                 return $fields;
 353         }
 354
 355         /**
 356          * Return the tables, fields, and join conditions to be selected to create
 357          * a new page object.
 358          * @since 1.31
 359          * @return array With three keys:
 360          *   - tables: (string[]) to include in the `$table` to `IDatabase->select()`
 361          *   - fields: (string[]) to include in the `$vars` to `IDatabase->select()`
 362          *   - joins: (array) to include in the `$join_conds` to `IDatabase->select()`
 363          */
 364         public static function getQueryInfo() {
 365                 global $wgContentHandlerUseDB, $wgPageLanguageUseDB;
 366
 367                 $ret = [
 368                         'tables' => [ 'page' ],
 369                         'fields' => [
 370                                 'page_id',
 371                                 'page_namespace',
 372                                 'page_title',
 373                                 'page_restrictions',
 374                                 'page_is_redirect',
 375                                 'page_is_new',
 376                                 'page_random',
 377                                 'page_touched',
 378                                 'page_links_updated',
 379                                 'page_latest',
 380                                 'page_len',
 381                         ],
 382                         'joins' => [],
 383                 ];
 384
 385                 if ( $wgContentHandlerUseDB ) {
 386                         $ret['fields'][] = 'page_content_model';
 387                 }
 388
 389                 if ( $wgPageLanguageUseDB ) {
 390                         $ret['fields'][] = 'page_lang';
 391                 }
 392
 393                 return $ret;
 394         }
 395
 396         /**
 397          * Fetch a page record with the given conditions
 398          * @param IDatabase $dbr
 399          * @param array $conditions
 400          * @param array $options
 401          * @return object|bool Database result resource, or false on failure
 402          */
 403         protected function pageData( $dbr, $conditions, $options = [] ) {
 404                 $pageQuery = self::getQueryInfo();
 405
 406                 // Avoid PHP 7.1 warning of passing $this by reference
 407                 $wikiPage = $this;
 408
 409                 Hooks::run( 'ArticlePageDataBefore', [
 410                         &$wikiPage, &$pageQuery['fields'], &$pageQuery['tables'], &$pageQuery['joins']
 411                 ] );
 412
 413                 $row = $dbr->selectRow(
 414                         $pageQuery['tables'],
 415                         $pageQuery['fields'],
 416                         $conditions,
 417                         __METHOD__,
 418                         $options,
 419                         $pageQuery['joins']
 420                 );
 421
 422                 Hooks::run( 'ArticlePageDataAfter', [ &$wikiPage, &$row ] );
 423
 424                 return $row;
 425         }
 426
 427         /**
 428          * Fetch a page record matching the Title object's namespace and title
 429          * using a sanitized title string
 430          *
 431          * @param IDatabase $dbr
 432          * @param Title $title
 433          * @param array $options
 434          * @return object|bool Database result resource, or false on failure
 435          */
 436         public function pageDataFromTitle( $dbr, $title, $options = [] ) {
 437                 return $this->pageData( $dbr, [
 438                         'page_namespace' => $title->getNamespace(),
 439                         'page_title' => $title->getDBkey() ], $options );
 440         }
 441
 442         /**
 443          * Fetch a page record matching the requested ID
 444          *
 445          * @param IDatabase $dbr
 446          * @param int $id
 447          * @param array $options
 448          * @return object|bool Database result resource, or false on failure
 449          */
 450         public function pageDataFromId( $dbr, $id, $options = [] ) {
 451                 return $this->pageData( $dbr, [ 'page_id' => $id ], $options );
 452         }
 453
 454         /**
 455          * Load the object from a given source by title
 456          *
 457          * @param object|string|int $from One of the following:
 458          *   - A DB query result object.
 459          *   - "fromdb" or WikiPage::READ_NORMAL to get from a replica DB.
 460          *   - "fromdbmaster" or WikiPage::READ_LATEST to get from the master DB.
 461          *   - "forupdate"  or WikiPage::READ_LOCKING to get from the master DB
 462          *     using SELECT FOR UPDATE.
 463          *
 464          * @return void
 465          */
 466         public function loadPageData( $from = 'fromdb' ) {
 467                 $from = self::convertSelectType( $from );
 468                 if ( is_int( $from ) && $from <= $this->mDataLoadedFrom ) {
 469                         // We already have the data from the correct location, no need to load it twice.
 470                         return;
 471                 }
 472
 473                 if ( is_int( $from ) ) {
 474                         list( $index, $opts ) = DBAccessObjectUtils::getDBOptions( $from );
 475                         $loadBalancer = $this->getDBLoadBalancer();
 476                         $db = $loadBalancer->getConnection( $index );
 477                         $data = $this->pageDataFromTitle( $db, $this->mTitle, $opts );
 478
 479                         if ( !$data
 480                                 && $index == DB_REPLICA
 481                                 && $loadBalancer->getServerCount() > 1
 482                                 && $loadBalancer->hasOrMadeRecentMasterChanges()
 483                         ) {
 484                                 $from = self::READ_LATEST;
 485                                 list( $index, $opts ) = DBAccessObjectUtils::getDBOptions( $from );
 486                                 $db = $loadBalancer->getConnection( $index );
 487                                 $data = $this->pageDataFromTitle( $db, $this->mTitle, $opts );
 488                         }
 489                 } else {
 490                         // No idea from where the caller got this data, assume replica DB.
 491                         $data = $from;
 492                         $from = self::READ_NORMAL;
 493                 }
 494
 495                 $this->loadFromRow( $data, $from );
 496         }
 497
 498         /**
 499          * Checks whether the page data was loaded using the given database access mode (or better).
 500          *
 501          * @since 1.32
 502          *
 503          * @param string|int $from One of the following:
 504          *   - "fromdb" or WikiPage::READ_NORMAL to get from a replica DB.
 505          *   - "fromdbmaster" or WikiPage::READ_LATEST to get from the master DB.
 506          *   - "forupdate"  or WikiPage::READ_LOCKING to get from the master DB
 507          *     using SELECT FOR UPDATE.
 508          *
 509          * @return bool
 510          */
 511         public function wasLoadedFrom( $from ) {
 512                 $from = self::convertSelectType( $from );
 513
 514                 if ( !is_int( $from ) ) {
 515                         // No idea from where the caller got this data, assume replica DB.
 516                         $from = self::READ_NORMAL;
 517                 }
 518
 519                 if ( is_int( $from ) && $from <= $this->mDataLoadedFrom ) {
 520                         return true;
 521                 }
 522
 523                 return false;
 524         }
 525
 526         /**
 527          * Load the object from a database row
 528          *
 529          * @since 1.20
 530          * @param object|bool $data DB row containing fields returned by selectFields() or false
 531          * @param string|int $from One of the following:
 532          *        - "fromdb" or WikiPage::READ_NORMAL if the data comes from a replica DB
 533          *        - "fromdbmaster" or WikiPage::READ_LATEST if the data comes from the master DB
 534          *        - "forupdate"  or WikiPage::READ_LOCKING if the data comes from
 535          *          the master DB using SELECT FOR UPDATE
 536          */
 537         public function loadFromRow( $data, $from ) {
 538                 $lc = MediaWikiServices::getInstance()->getLinkCache();
 539                 $lc->clearLink( $this->mTitle );
 540
 541                 if ( $data ) {
 542                         $lc->addGoodLinkObjFromRow( $this->mTitle, $data );
 543
 544                         $this->mTitle->loadFromRow( $data );
 545
 546                         // Old-fashioned restrictions
 547                         $this->mTitle->loadRestrictions( $data->page_restrictions );
 548
 549                         $this->mId = intval( $data->page_id );
 550                         $this->mTouched = wfTimestamp( TS_MW, $data->page_touched );
 551                         $this->mLinksUpdated = wfTimestampOrNull( TS_MW, $data->page_links_updated );
 552                         $this->mIsRedirect = intval( $data->page_is_redirect );
 553                         $this->mLatest = intval( $data->page_latest );
 554                         // T39225: $latest may no longer match the cached latest Revision object.
 555                         // Double-check the ID of any cached latest Revision object for consistency.
 556                         if ( $this->mLastRevision && $this->mLastRevision->getId() != $this->mLatest ) {
 557                                 $this->mLastRevision = null;
 558                                 $this->mTimestamp = '';
 559                         }
 560                 } else {
 561                         $lc->addBadLinkObj( $this->mTitle );
 562
 563                         $this->mTitle->loadFromRow( false );
 564
 565                         $this->clearCacheFields();
 566
 567                         $this->mId = 0;
 568                 }
 569
 570                 $this->mDataLoaded = true;
 571                 $this->mDataLoadedFrom = self::convertSelectType( $from );
 572         }
 573
 574         /**
 575          * @return int Page ID
 576          */
 577         public function getId() {
 578                 if ( !$this->mDataLoaded ) {
 579                         $this->loadPageData();
 580                 }
 581                 return $this->mId;
 582         }
 583
 584         /**
 585          * @return bool Whether or not the page exists in the database
 586          */
 587         public function exists() {
 588                 if ( !$this->mDataLoaded ) {
 589                         $this->loadPageData();
 590                 }
 591                 return $this->mId > 0;
 592         }
 593
 594         /**
 595          * Check if this page is something we're going to be showing
 596          * some sort of sensible content for. If we return false, page
 597          * views (plain action=view) will return an HTTP 404 response,
 598          * so spiders and robots can know they're following a bad link.
 599          *
 600          * @return bool
 601          */
 602         public function hasViewableContent() {
 603                 return $this->mTitle->isKnown();
 604         }
 605
 606         /**
 607          * Tests if the article content represents a redirect
 608          *
 609          * @return bool
 610          */
 611         public function isRedirect() {
 612                 if ( !$this->mDataLoaded ) {
 613                         $this->loadPageData();
 614                 }
 615
 616                 return (bool)$this->mIsRedirect;
 617         }
 618
 619         /**
 620          * Returns the page's content model id (see the CONTENT_MODEL_XXX constants).
 621          *
 622          * Will use the revisions actual content model if the page exists,
 623          * and the page's default if the page doesn't exist yet.
 624          *
 625          * @return string
 626          *
 627          * @since 1.21
 628          */
 629         public function getContentModel() {
 630                 if ( $this->exists() ) {
 631                         $cache = ObjectCache::getMainWANInstance();
 632
 633                         return $cache->getWithSetCallback(
 634                                 $cache->makeKey( 'page-content-model', $this->getLatest() ),
 635                                 $cache::TTL_MONTH,
 636                                 function () {
 637                                         $rev = $this->getRevision();
 638                                         if ( $rev ) {
 639                                                 // Look at the revision's actual content model
 640                                                 return $rev->getContentModel();
 641                                         } else {
 642                                                 $title = $this->mTitle->getPrefixedDBkey();
 643                                                 wfWarn( "Page $title exists but has no (visible) revisions!" );
 644                                                 return $this->mTitle->getContentModel();
 645                                         }
 646                                 }
 647                         );
 648                 }
 649
 650                 // use the default model for this page
 651                 return $this->mTitle->getContentModel();
 652         }
 653
 654         /**
 655          * Loads page_touched and returns a value indicating if it should be used
 656          * @return bool True if this page exists and is not a redirect
 657          */
 658         public function checkTouched() {
 659                 if ( !$this->mDataLoaded ) {
 660                         $this->loadPageData();
 661                 }
 662                 return ( $this->mId && !$this->mIsRedirect );
 663         }
 664
 665         /**
 666          * Get the page_touched field
 667          * @return string Containing GMT timestamp
 668          */
 669         public function getTouched() {
 670                 if ( !$this->mDataLoaded ) {
 671                         $this->loadPageData();
 672                 }
 673                 return $this->mTouched;
 674         }
 675
 676         /**
 677          * Get the page_links_updated field
 678          * @return string|null Containing GMT timestamp
 679          */
 680         public function getLinksTimestamp() {
 681                 if ( !$this->mDataLoaded ) {
 682                         $this->loadPageData();
 683                 }
 684                 return $this->mLinksUpdated;
 685         }
 686
 687         /**
 688          * Get the page_latest field
 689          * @return int The rev_id of current revision
 690          */
 691         public function getLatest() {
 692                 if ( !$this->mDataLoaded ) {
 693                         $this->loadPageData();
 694                 }
 695                 return (int)$this->mLatest;
 696         }
 697
 698         /**
 699          * Get the Revision object of the oldest revision
 700          * @return Revision|null
 701          */
 702         public function getOldestRevision() {
 703                 // Try using the replica DB first, then try the master
 704                 $rev = $this->mTitle->getFirstRevision();
 705                 if ( !$rev ) {
 706                         $rev = $this->mTitle->getFirstRevision( Title::GAID_FOR_UPDATE );
 707                 }
 708                 return $rev;
 709         }
 710
 711         /**
 712          * Loads everything except the text
 713          * This isn't necessary for all uses, so it's only done if needed.
 714          */
 715         protected function loadLastEdit() {
 716                 if ( $this->mLastRevision !== null ) {
 717                         return; // already loaded
 718                 }
 719
 720                 $latest = $this->getLatest();
 721                 if ( !$latest ) {
 722                         return; // page doesn't exist or is missing page_latest info
 723                 }
 724
 725                 if ( $this->mDataLoadedFrom == self::READ_LOCKING ) {
 726                         // T39225: if session S1 loads the page row FOR UPDATE, the result always
 727                         // includes the latest changes committed. This is true even within REPEATABLE-READ
 728                         // transactions, where S1 normally only sees changes committed before the first S1
 729                         // SELECT. Thus we need S1 to also gets the revision row FOR UPDATE; otherwise, it
 730                         // may not find it since a page row UPDATE and revision row INSERT by S2 may have
 731                         // happened after the first S1 SELECT.
 732                         // https://dev.mysql.com/doc/refman/5.0/en/set-transaction.html#isolevel_repeatable-read
 733                         $flags = Revision::READ_LOCKING;
 734                         $revision = Revision::newFromPageId( $this->getId(), $latest, $flags );
 735                 } elseif ( $this->mDataLoadedFrom == self::READ_LATEST ) {
 736                         // Bug T93976: if page_latest was loaded from the master, fetch the
 737                         // revision from there as well, as it may not exist yet on a replica DB.
 738                         // Also, this keeps the queries in the same REPEATABLE-READ snapshot.
 739                         $flags = Revision::READ_LATEST;
 740                         $revision = Revision::newFromPageId( $this->getId(), $latest, $flags );
 741                 } else {
 742                         $dbr = wfGetDB( DB_REPLICA );
 743                         $revision = Revision::newKnownCurrent( $dbr, $this->getTitle(), $latest );
 744                 }
 745
 746                 if ( $revision ) { // sanity
 747                         $this->setLastEdit( $revision );
 748                 }
 749         }
 750
 751         /**
 752          * Set the latest revision
 753          * @param Revision $revision
 754          */
 755         protected function setLastEdit( Revision $revision ) {
 756                 $this->mLastRevision = $revision;
 757                 $this->mTimestamp = $revision->getTimestamp();
 758         }
 759
 760         /**
 761          * Get the latest revision
 762          * @return Revision|null
 763          */
 764         public function getRevision() {
 765                 $this->loadLastEdit();
 766                 if ( $this->mLastRevision ) {
 767                         return $this->mLastRevision;
 768                 }
 769                 return null;
 770         }
 771
 772         /**
 773          * Get the content of the current revision. No side-effects...
 774          *
 775          * @param int $audience One of:
 776          *   Revision::FOR_PUBLIC       to be displayed to all users
 777          *   Revision::FOR_THIS_USER    to be displayed to $wgUser
 778          *   Revision::RAW              get the text regardless of permissions
 779          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 780          *   to the $audience parameter
 781          * @return Content|null The content of the current revision
 782          *
 783          * @since 1.21
 784          */
 785         public function getContent( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 786                 $this->loadLastEdit();
 787                 if ( $this->mLastRevision ) {
 788                         return $this->mLastRevision->getContent( $audience, $user );
 789                 }
 790                 return null;
 791         }
 792
 793         /**
 794          * @return string MW timestamp of last article revision
 795          */
 796         public function getTimestamp() {
 797                 // Check if the field has been filled by WikiPage::setTimestamp()
 798                 if ( !$this->mTimestamp ) {
 799                         $this->loadLastEdit();
 800                 }
 801
 802                 return wfTimestamp( TS_MW, $this->mTimestamp );
 803         }
 804
 805         /**
 806          * Set the page timestamp (use only to avoid DB queries)
 807          * @param string $ts MW timestamp of last article revision
 808          * @return void
 809          */
 810         public function setTimestamp( $ts ) {
 811                 $this->mTimestamp = wfTimestamp( TS_MW, $ts );
 812         }
 813
 814         /**
 815          * @param int $audience One of:
 816          *   Revision::FOR_PUBLIC       to be displayed to all users
 817          *   Revision::FOR_THIS_USER    to be displayed to the given user
 818          *   Revision::RAW              get the text regardless of permissions
 819          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 820          *   to the $audience parameter
 821          * @return int User ID for the user that made the last article revision
 822          */
 823         public function getUser( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 824                 $this->loadLastEdit();
 825                 if ( $this->mLastRevision ) {
 826                         return $this->mLastRevision->getUser( $audience, $user );
 827                 } else {
 828                         return -1;
 829                 }
 830         }
 831
 832         /**
 833          * Get the User object of the user who created the page
 834          * @param int $audience One of:
 835          *   Revision::FOR_PUBLIC       to be displayed to all users
 836          *   Revision::FOR_THIS_USER    to be displayed to the given user
 837          *   Revision::RAW              get the text regardless of permissions
 838          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 839          *   to the $audience parameter
 840          * @return User|null
 841          */
 842         public function getCreator( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 843                 $revision = $this->getOldestRevision();
 844                 if ( $revision ) {
 845                         $userName = $revision->getUserText( $audience, $user );
 846                         return User::newFromName( $userName, false );
 847                 } else {
 848                         return null;
 849                 }
 850         }
 851
 852         /**
 853          * @param int $audience One of:
 854          *   Revision::FOR_PUBLIC       to be displayed to all users
 855          *   Revision::FOR_THIS_USER    to be displayed to the given user
 856          *   Revision::RAW              get the text regardless of permissions
 857          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 858          *   to the $audience parameter
 859          * @return string Username of the user that made the last article revision
 860          */
 861         public function getUserText( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 862                 $this->loadLastEdit();
 863                 if ( $this->mLastRevision ) {
 864                         return $this->mLastRevision->getUserText( $audience, $user );
 865                 } else {
 866                         return '';
 867                 }
 868         }
 869
 870         /**
 871          * @param int $audience One of:
 872          *   Revision::FOR_PUBLIC       to be displayed to all users
 873          *   Revision::FOR_THIS_USER    to be displayed to the given user
 874          *   Revision::RAW              get the text regardless of permissions
 875          * @param User|null $user User object to check for, only if FOR_THIS_USER is passed
 876          *   to the $audience parameter
 877          * @return string Comment stored for the last article revision
 878          */
 879         public function getComment( $audience = Revision::FOR_PUBLIC, User $user = null ) {
 880                 $this->loadLastEdit();
 881                 if ( $this->mLastRevision ) {
 882                         return $this->mLastRevision->getComment( $audience, $user );
 883                 } else {
 884                         return '';
 885                 }
 886         }
 887
 888         /**
 889          * Returns true if last revision was marked as "minor edit"
 890          *
 891          * @return bool Minor edit indicator for the last article revision.
 892          */
 893         public function getMinorEdit() {
 894                 $this->loadLastEdit();
 895                 if ( $this->mLastRevision ) {
 896                         return $this->mLastRevision->isMinor();
 897                 } else {
 898                         return false;
 899                 }
 900         }
 901
 902         /**
 903          * Determine whether a page would be suitable for being counted as an
 904          * article in the site_stats table based on the title & its content
 905          *
 906          * @param PreparedEdit|bool $editInfo (false): object returned by prepareTextForEdit(),
 907          *   if false, the current database state will be used
 908          * @return bool
 909          */
 910         public function isCountable( $editInfo = false ) {
 911                 global $wgArticleCountMethod;
 912
 913                 // NOTE: Keep in sync with DerivedPageDataUpdater::isCountable.
 914
 915                 if ( !$this->mTitle->isContentPage() ) {
 916                         return false;
 917                 }
 918
 919                 if ( $editInfo ) {
 920                         // NOTE: only the main slot can make a page a redirect
 921                         $content = $editInfo->pstContent;
 922                 } else {
 923                         $content = $this->getContent();
 924                 }
 925
 926                 if ( !$content || $content->isRedirect() ) {
 927                         return false;
 928                 }
 929
 930                 $hasLinks = null;
 931
 932                 if ( $wgArticleCountMethod === 'link' ) {
 933                         // nasty special case to avoid re-parsing to detect links
 934
 935                         if ( $editInfo ) {
 936                                 // ParserOutput::getLinks() is a 2D array of page links, so
 937                                 // to be really correct we would need to recurse in the array
 938                                 // but the main array should only have items in it if there are
 939                                 // links.
 940                                 $hasLinks = (bool)count( $editInfo->output->getLinks() );
 941                         } else {
 942                                 // NOTE: keep in sync with revisionRenderer::getLinkCount
 943                                 $hasLinks = (bool)wfGetDB( DB_REPLICA )->selectField( 'pagelinks', 1,
 944                                         [ 'pl_from' => $this->getId() ], __METHOD__ );
 945                         }
 946                 }
 947
 948                 return $content->isCountable( $hasLinks );
 949         }
 950
 951         /**
 952          * If this page is a redirect, get its target
 953          *
 954          * The target will be fetched from the redirect table if possible.
 955          * If this page doesn't have an entry there, call insertRedirect()
 956          * @return Title|null Title object, or null if this page is not a redirect
 957          */
 958         public function getRedirectTarget() {
 959                 if ( !$this->mTitle->isRedirect() ) {
 960                         return null;
 961                 }
 962
 963                 if ( $this->mRedirectTarget !== null ) {
 964                         return $this->mRedirectTarget;
 965                 }
 966
 967                 // Query the redirect table
 968                 $dbr = wfGetDB( DB_REPLICA );
 969                 $row = $dbr->selectRow( 'redirect',
 970                         [ 'rd_namespace', 'rd_title', 'rd_fragment', 'rd_interwiki' ],
 971                         [ 'rd_from' => $this->getId() ],
 972                         __METHOD__
 973                 );
 974
 975                 // rd_fragment and rd_interwiki were added later, populate them if empty
 976                 if ( $row && !is_null( $row->rd_fragment ) && !is_null( $row->rd_interwiki ) ) {
 977                         $this->mRedirectTarget = Title::makeTitle(
 978                                 $row->rd_namespace, $row->rd_title,
 979                                 $row->rd_fragment, $row->rd_interwiki
 980                         );
 981                         return $this->mRedirectTarget;
 982                 }
 983
 984                 // This page doesn't have an entry in the redirect table
 985                 $this->mRedirectTarget = $this->insertRedirect();
 986                 return $this->mRedirectTarget;
 987         }
 988
 989         /**
 990          * Insert an entry for this page into the redirect table if the content is a redirect
 991          *
 992          * The database update will be deferred via DeferredUpdates
 993          *
 994          * Don't call this function directly unless you know what you're doing.
 995          * @return Title|null Title object or null if not a redirect
 996          */
 997         public function insertRedirect() {
 998                 $content = $this->getContent();
 999                 $retval = $content ? $content->getUltimateRedirectTarget() : null;
1000                 if ( !$retval ) {
1001                         return null;
1002                 }
1003
1004                 // Update the DB post-send if the page has not cached since now
1005                 $latest = $this->getLatest();
1006                 DeferredUpdates::addCallableUpdate(
1007                         function () use ( $retval, $latest ) {
1008                                 $this->insertRedirectEntry( $retval, $latest );
1009                         },
1010                         DeferredUpdates::POSTSEND,
1011                         wfGetDB( DB_MASTER )
1012                 );
1013
1014                 return $retval;
1015         }
1016
1017         /**
1018          * Insert or update the redirect table entry for this page to indicate it redirects to $rt
1019          * @param Title $rt Redirect target
1020          * @param int|null $oldLatest Prior page_latest for check and set
1021          */
1022         public function insertRedirectEntry( Title $rt, $oldLatest = null ) {
1023                 $dbw = wfGetDB( DB_MASTER );
1024                 $dbw->startAtomic( __METHOD__ );
1025
1026                 if ( !$oldLatest || $oldLatest == $this->lockAndGetLatest() ) {
1027                         $dbw->upsert(
1028                                 'redirect',
1029                                 [
1030                                         'rd_from' => $this->getId(),
1031                                         'rd_namespace' => $rt->getNamespace(),
1032                                         'rd_title' => $rt->getDBkey(),
1033                                         'rd_fragment' => $rt->getFragment(),
1034                                         'rd_interwiki' => $rt->getInterwiki(),
1035                                 ],
1036                                 [ 'rd_from' ],
1037                                 [
1038                                         'rd_namespace' => $rt->getNamespace(),
1039                                         'rd_title' => $rt->getDBkey(),
1040                                         'rd_fragment' => $rt->getFragment(),
1041                                         'rd_interwiki' => $rt->getInterwiki(),
1042                                 ],
1043                                 __METHOD__
1044                         );
1045                 }
1046
1047                 $dbw->endAtomic( __METHOD__ );
1048         }
1049
1050         /**
1051          * Get the Title object or URL this page redirects to
1052          *
1053          * @return bool|Title|string False, Title of in-wiki target, or string with URL
1054          */
1055         public function followRedirect() {
1056                 return $this->getRedirectURL( $this->getRedirectTarget() );
1057         }
1058
1059         /**
1060          * Get the Title object or URL to use for a redirect. We use Title
1061          * objects for same-wiki, non-special redirects and URLs for everything
1062          * else.
1063          * @param Title $rt Redirect target
1064          * @return bool|Title|string False, Title object of local target, or string with URL
1065          */
1066         public function getRedirectURL( $rt ) {
1067                 if ( !$rt ) {
1068                         return false;
1069                 }
1070
1071                 if ( $rt->isExternal() ) {
1072                         if ( $rt->isLocal() ) {
1073                                 // Offsite wikis need an HTTP redirect.
1074                                 // This can be hard to reverse and may produce loops,
1075                                 // so they may be disabled in the site configuration.
1076                                 $source = $this->mTitle->getFullURL( 'redirect=no' );
1077                                 return $rt->getFullURL( [ 'rdfrom' => $source ] );
1078                         } else {
1079                                 // External pages without "local" bit set are not valid
1080                                 // redirect targets
1081                                 return false;
1082                         }
1083                 }
1084
1085                 if ( $rt->isSpecialPage() ) {
1086                         // Gotta handle redirects to special pages differently:
1087                         // Fill the HTTP response "Location" header and ignore the rest of the page we're on.
1088                         // Some pages are not valid targets.
1089                         if ( $rt->isValidRedirectTarget() ) {
1090                                 return $rt->getFullURL();
1091                         } else {
1092                                 return false;
1093                         }
1094                 }
1095
1096                 return $rt;
1097         }
1098
1099         /**
1100          * Get a list of users who have edited this article, not including the user who made
1101          * the most recent revision, which you can get from $article->getUser() if you want it
1102          * @return UserArrayFromResult
1103          */
1104         public function getContributors() {
1105                 // @todo: This is expensive; cache this info somewhere.
1106
1107                 $dbr = wfGetDB( DB_REPLICA );
1108
1109                 $actorMigration = ActorMigration::newMigration();
1110                 $actorQuery = $actorMigration->getJoin( 'rev_user' );
1111
1112                 $tables = array_merge( [ 'revision' ], $actorQuery['tables'], [ 'user' ] );
1113
1114                 $fields = [
1115                         'user_id' => $actorQuery['fields']['rev_user'],
1116                         'user_name' => $actorQuery['fields']['rev_user_text'],
1117                         'actor_id' => $actorQuery['fields']['rev_actor'],
1118                         'user_real_name' => 'MIN(user_real_name)',
1119                         'timestamp' => 'MAX(rev_timestamp)',
1120                 ];
1121
1122                 $conds = [ 'rev_page' => $this->getId() ];
1123
1124                 // The user who made the top revision gets credited as "this page was last edited by
1125                 // John, based on contributions by Tom, Dick and Harry", so don't include them twice.
1126                 $user = $this->getUser()
1127                         ? User::newFromId( $this->getUser() )
1128                         : User::newFromName( $this->getUserText(), false );
1129                 $conds[] = 'NOT(' . $actorMigration->getWhere( $dbr, 'rev_user', $user )['conds'] . ')';
1130
1131                 // Username hidden?
1132                 $conds[] = "{$dbr->bitAnd( 'rev_deleted', Revision::DELETED_USER )} = 0";
1133
1134                 $jconds = [
1135                         'user' => [ 'LEFT JOIN', $actorQuery['fields']['rev_user'] . ' = user_id' ],
1136                 ] + $actorQuery['joins'];
1137
1138                 $options = [
1139                         'GROUP BY' => [ $fields['user_id'], $fields['user_name'] ],
1140                         'ORDER BY' => 'timestamp DESC',
1141                 ];
1142
1143                 $res = $dbr->select( $tables, $fields, $conds, __METHOD__, $options, $jconds );
1144                 return new UserArrayFromResult( $res );
1145         }
1146
1147         /**
1148          * Should the parser cache be used?
1149          *
1150          * @param ParserOptions $parserOptions ParserOptions to check
1151          * @param int $oldId
1152          * @return bool
1153          */
1154         public function shouldCheckParserCache( ParserOptions $parserOptions, $oldId ) {
1155                 return $parserOptions->getStubThreshold() == 0
1156                         && $this->exists()
1157                         && ( $oldId === null || $oldId === 0 || $oldId === $this->getLatest() )
1158                         && $this->getContentHandler()->isParserCacheSupported();
1159         }
1160
1161         /**
1162          * Get a ParserOutput for the given ParserOptions and revision ID.
1163          *
1164          * The parser cache will be used if possible. Cache misses that result
1165          * in parser runs are debounced with PoolCounter.
1166          *
1167          * @since 1.19
1168          * @param ParserOptions $parserOptions ParserOptions to use for the parse operation
1169          * @param null|int $oldid Revision ID to get the text from, passing null or 0 will
1170          *   get the current revision (default value)
1171          * @param bool $forceParse Force reindexing, regardless of cache settings
1172          * @return bool|ParserOutput ParserOutput or false if the revision was not found
1173          */
1174         public function getParserOutput(
1175                 ParserOptions $parserOptions, $oldid = null, $forceParse = false
1176         ) {
1177                 $useParserCache =
1178                         ( !$forceParse ) && $this->shouldCheckParserCache( $parserOptions, $oldid );
1179
1180                 if ( $useParserCache && !$parserOptions->isSafeToCache() ) {
1181                         throw new InvalidArgumentException(
1182                                 'The supplied ParserOptions are not safe to cache. Fix the options or set $forceParse = true.'
1183                         );
1184                 }
1185
1186                 wfDebug( __METHOD__ .
1187                         ': using parser cache: ' . ( $useParserCache ? 'yes' : 'no' ) . "\n" );
1188                 if ( $parserOptions->getStubThreshold() ) {
1189                         wfIncrStats( 'pcache.miss.stub' );
1190                 }
1191
1192                 if ( $useParserCache ) {
1193                         $parserOutput = $this->getParserCache()
1194                                 ->get( $this, $parserOptions );
1195                         if ( $parserOutput !== false ) {
1196                                 return $parserOutput;
1197                         }
1198                 }
1199
1200                 if ( $oldid === null || $oldid === 0 ) {
1201                         $oldid = $this->getLatest();
1202                 }
1203
1204                 $pool = new PoolWorkArticleView( $this, $parserOptions, $oldid, $useParserCache );
1205                 $pool->execute();
1206
1207                 return $pool->getParserOutput();
1208         }
1209
1210         /**
1211          * Do standard deferred updates after page view (existing or missing page)
1212          * @param User $user The relevant user
1213          * @param int $oldid Revision id being viewed; if not given or 0, latest revision is assumed
1214          */
1215         public function doViewUpdates( User $user, $oldid = 0 ) {
1216                 if ( wfReadOnly() ) {
1217                         return;
1218                 }
1219
1220                 // Update newtalk / watchlist notification status;
1221                 // Avoid outage if the master is not reachable by using a deferred updated
1222                 DeferredUpdates::addCallableUpdate(
1223                         function () use ( $user, $oldid ) {
1224                                 Hooks::run( 'PageViewUpdates', [ $this, $user ] );
1225
1226                                 $user->clearNotification( $this->mTitle, $oldid );
1227                         },
1228                         DeferredUpdates::PRESEND
1229                 );
1230         }
1231
1232         /**
1233          * Perform the actions of a page purging
1234          * @return bool
1235          * @note In 1.28 (and only 1.28), this took a $flags parameter that
1236          *  controlled how much purging was done.
1237          */
1238         public function doPurge() {
1239                 // Avoid PHP 7.1 warning of passing $this by reference
1240                 $wikiPage = $this;
1241
1242                 if ( !Hooks::run( 'ArticlePurge', [ &$wikiPage ] ) ) {
1243                         return false;
1244                 }
1245
1246                 $this->mTitle->invalidateCache();
1247
1248                 // Clear file cache
1249                 HTMLFileCache::clearFileCache( $this->getTitle() );
1250                 // Send purge after above page_touched update was committed
1251                 DeferredUpdates::addUpdate(
1252                         new CdnCacheUpdate( $this->mTitle->getCdnUrls() ),
1253                         DeferredUpdates::PRESEND
1254                 );
1255
1256                 if ( $this->mTitle->getNamespace() == NS_MEDIAWIKI ) {
1257                         $messageCache = MessageCache::singleton();
1258                         $messageCache->updateMessageOverride( $this->mTitle, $this->getContent() );
1259                 }
1260
1261                 return true;
1262         }
1263
1264         /**
1265          * Insert a new empty page record for this article.
1266          * This *must* be followed up by creating a revision
1267          * and running $this->updateRevisionOn( ... );
1268          * or else the record will be left in a funky state.
1269          * Best if all done inside a transaction.
1270          *
1271          * @todo Factor out into a PageStore service, to be used by PageUpdater.
1272          *
1273          * @param IDatabase $dbw
1274          * @param int|null $pageId Custom page ID that will be used for the insert statement
1275          *
1276          * @return bool|int The newly created page_id key; false if the row was not
1277          *   inserted, e.g. because the title already existed or because the specified
1278          *   page ID is already in use.
1279          */
1280         public function insertOn( $dbw, $pageId = null ) {
1281                 $pageIdForInsert = $pageId ? [ 'page_id' => $pageId ] : [];
1282                 $dbw->insert(
1283                         'page',
1284                         [
1285                                 'page_namespace'    => $this->mTitle->getNamespace(),
1286                                 'page_title'        => $this->mTitle->getDBkey(),
1287                                 'page_restrictions' => '',
1288                                 'page_is_redirect'  => 0, // Will set this shortly...
1289                                 'page_is_new'       => 1,
1290                                 'page_random'       => wfRandom(),
1291                                 'page_touched'      => $dbw->timestamp(),
1292                                 'page_latest'       => 0, // Fill this in shortly...
1293                                 'page_len'          => 0, // Fill this in shortly...
1294                         ] + $pageIdForInsert,
1295                         __METHOD__,
1296                         'IGNORE'
1297                 );
1298
1299                 if ( $dbw->affectedRows() > 0 ) {
1300                         $newid = $pageId ? (int)$pageId : $dbw->insertId();
1301                         $this->mId = $newid;
1302                         $this->mTitle->resetArticleID( $newid );
1303
1304                         return $newid;
1305                 } else {
1306                         return false; // nothing changed
1307                 }
1308         }
1309
1310         /**
1311          * Update the page record to point to a newly saved revision.
1312          *
1313          * @todo Factor out into a PageStore service, or move into PageUpdater.
1314          *
1315          * @param IDatabase $dbw
1316          * @param Revision $revision For ID number, and text used to set
1317          *   length and redirect status fields
1318          * @param int|null $lastRevision If given, will not overwrite the page field
1319          *   when different from the currently set value.
1320          *   Giving 0 indicates the new page flag should be set on.
1321          * @param bool|null $lastRevIsRedirect If given, will optimize adding and
1322          *   removing rows in redirect table.
1323          * @return bool Success; false if the page row was missing or page_latest changed
1324          */
1325         public function updateRevisionOn( $dbw, $revision, $lastRevision = null,
1326                 $lastRevIsRedirect = null
1327         ) {
1328                 global $wgContentHandlerUseDB;
1329
1330                 // TODO: move into PageUpdater or PageStore
1331                 // NOTE: when doing that, make sure cached fields get reset in doEditContent,
1332                 // and in the compat stub!
1333
1334                 // Assertion to try to catch T92046
1335                 if ( (int)$revision->getId() === 0 ) {
1336                         throw new InvalidArgumentException(
1337                                 __METHOD__ . ': Revision has ID ' . var_export( $revision->getId(), 1 )
1338                         );
1339                 }
1340
1341                 $content = $revision->getContent();
1342                 $len = $content ? $content->getSize() : 0;
1343                 $rt = $content ? $content->getUltimateRedirectTarget() : null;
1344
1345                 $conditions = [ 'page_id' => $this->getId() ];
1346
1347                 if ( !is_null( $lastRevision ) ) {
1348                         // An extra check against threads stepping on each other
1349                         $conditions['page_latest'] = $lastRevision;
1350                 }
1351
1352                 $revId = $revision->getId();
1353                 Assert::parameter( $revId > 0, '$revision->getId()', 'must be > 0' );
1354
1355                 $row = [ /* SET */
1356                         'page_latest'      => $revId,
1357                         'page_touched'     => $dbw->timestamp( $revision->getTimestamp() ),
1358                         'page_is_new'      => ( $lastRevision === 0 ) ? 1 : 0,
1359                         'page_is_redirect' => $rt !== null ? 1 : 0,
1360                         'page_len'         => $len,
1361                 ];
1362
1363                 if ( $wgContentHandlerUseDB ) {
1364                         $row['page_content_model'] = $revision->getContentModel();
1365                 }
1366
1367                 $dbw->update( 'page',
1368                         $row,
1369                         $conditions,
1370                         __METHOD__ );
1371
1372                 $result = $dbw->affectedRows() > 0;
1373                 if ( $result ) {
1374                         $this->updateRedirectOn( $dbw, $rt, $lastRevIsRedirect );
1375                         $this->setLastEdit( $revision );
1376                         $this->mLatest = $revision->getId();
1377                         $this->mIsRedirect = (bool)$rt;
1378                         // Update the LinkCache.
1379                         $linkCache = MediaWikiServices::getInstance()->getLinkCache();
1380                         $linkCache->addGoodLinkObj(
1381                                 $this->getId(),
1382                                 $this->mTitle,
1383                                 $len,
1384                                 $this->mIsRedirect,
1385                                 $this->mLatest,
1386                                 $revision->getContentModel()
1387                         );
1388                 }
1389
1390                 return $result;
1391         }
1392
1393         /**
1394          * Add row to the redirect table if this is a redirect, remove otherwise.
1395          *
1396          * @param IDatabase $dbw
1397          * @param Title|null $redirectTitle Title object pointing to the redirect target,
1398          *   or NULL if this is not a redirect
1399          * @param null|bool $lastRevIsRedirect If given, will optimize adding and
1400          *   removing rows in redirect table.
1401          * @return bool True on success, false on failure
1402          * @private
1403          */
1404         public function updateRedirectOn( $dbw, $redirectTitle, $lastRevIsRedirect = null ) {
1405                 // Always update redirects (target link might have changed)
1406                 // Update/Insert if we don't know if the last revision was a redirect or not
1407                 // Delete if changing from redirect to non-redirect
1408                 $isRedirect = !is_null( $redirectTitle );
1409
1410                 if ( !$isRedirect && $lastRevIsRedirect === false ) {
1411                         return true;
1412                 }
1413
1414                 if ( $isRedirect ) {
1415                         $this->insertRedirectEntry( $redirectTitle );
1416                 } else {
1417                         // This is not a redirect, remove row from redirect table
1418                         $where = [ 'rd_from' => $this->getId() ];
1419                         $dbw->delete( 'redirect', $where, __METHOD__ );
1420                 }
1421
1422                 if ( $this->getTitle()->getNamespace() == NS_FILE ) {
1423                         RepoGroup::singleton()->getLocalRepo()->invalidateImageRedirect( $this->getTitle() );
1424                 }
1425
1426                 return ( $dbw->affectedRows() != 0 );
1427         }
1428
1429         /**
1430          * If the given revision is newer than the currently set page_latest,
1431          * update the page record. Otherwise, do nothing.
1432          *
1433          * @deprecated since 1.24, use updateRevisionOn instead
1434          *
1435          * @param IDatabase $dbw
1436          * @param Revision $revision
1437          * @return bool
1438          */
1439         public function updateIfNewerOn( $dbw, $revision ) {
1440                 $row = $dbw->selectRow(
1441                         [ 'revision', 'page' ],
1442                         [ 'rev_id', 'rev_timestamp', 'page_is_redirect' ],
1443                         [
1444                                 'page_id' => $this->getId(),
1445                                 'page_latest=rev_id' ],
1446                         __METHOD__ );
1447
1448                 if ( $row ) {
1449                         if ( wfTimestamp( TS_MW, $row->rev_timestamp ) >= $revision->getTimestamp() ) {
1450                                 return false;
1451                         }
1452                         $prev = $row->rev_id;
1453                         $lastRevIsRedirect = (bool)$row->page_is_redirect;
1454                 } else {
1455                         // No or missing previous revision; mark the page as new
1456                         $prev = 0;
1457                         $lastRevIsRedirect = null;
1458                 }
1459
1460                 $ret = $this->updateRevisionOn( $dbw, $revision, $prev, $lastRevIsRedirect );
1461
1462                 return $ret;
1463         }
1464
1465         /**
1466          * Helper method for checking whether two revisions have differences that go
1467          * beyond the main slot.
1468          *
1469          * MCR migration note: this method should go away!
1470          *
1471          * @deprecated Use only as a stop-gap before refactoring to support MCR.
1472          *
1473          * @param Revision $a
1474          * @param Revision $b
1475          * @return bool
1476          */
1477         public static function hasDifferencesOutsideMainSlot( Revision $a, Revision $b ) {
1478                 $aSlots = $a->getRevisionRecord()->getSlots();
1479                 $bSlots = $b->getRevisionRecord()->getSlots();
1480                 $changedRoles = $aSlots->getRolesWithDifferentContent( $bSlots );
1481
1482                 return ( $changedRoles !== [ 'main' ] && $changedRoles !== [] );
1483         }
1484
1485         /**
1486          * Get the content that needs to be saved in order to undo all revisions
1487          * between $undo and $undoafter. Revisions must belong to the same page,
1488          * must exist and must not be deleted
1489          *
1490          * @param Revision $undo
1491          * @param Revision $undoafter Must be an earlier revision than $undo
1492          * @return Content|bool Content on success, false on failure
1493          * @since 1.21
1494          * Before we had the Content object, this was done in getUndoText
1495          */
1496         public function getUndoContent( Revision $undo, Revision $undoafter ) {
1497                 // TODO: MCR: replace this with a method that returns a RevisionSlotsUpdate
1498
1499                 if ( self::hasDifferencesOutsideMainSlot( $undo, $undoafter ) ) {
1500                         // Cannot yet undo edits that involve anything other the main slot.
1501                         return false;
1502                 }
1503
1504                 $handler = $undo->getContentHandler();
1505                 return $handler->getUndoContent( $this->getRevision(), $undo, $undoafter );
1506         }
1507
1508         /**
1509          * Returns true if this page's content model supports sections.
1510          *
1511          * @return bool
1512          *
1513          * @todo The skin should check this and not offer section functionality if
1514          *   sections are not supported.
1515          * @todo The EditPage should check this and not offer section functionality
1516          *   if sections are not supported.
1517          */
1518         public function supportsSections() {
1519                 return $this->getContentHandler()->supportsSections();
1520         }
1521
1522         /**
1523          * @param string|int|null|bool $sectionId Section identifier as a number or string
1524          * (e.g. 0, 1 or 'T-1'), null/false or an empty string for the whole page
1525          * or 'new' for a new section.
1526          * @param Content $sectionContent New content of the section.
1527          * @param string $sectionTitle New section's subject, only if $section is "new".
1528          * @param string $edittime Revision timestamp or null to use the current revision.
1529          *
1530          * @throws MWException
1531          * @return Content|null New complete article content, or null if error.
1532          *
1533          * @since 1.21
1534          * @deprecated since 1.24, use replaceSectionAtRev instead
1535          */
1536         public function replaceSectionContent(
1537                 $sectionId, Content $sectionContent, $sectionTitle = '', $edittime = null
1538         ) {
1539                 $baseRevId = null;
1540                 if ( $edittime && $sectionId !== 'new' ) {
1541                         $lb = $this->getDBLoadBalancer();
1542                         $dbr = $lb->getConnection( DB_REPLICA );
1543                         $rev = Revision::loadFromTimestamp( $dbr, $this->mTitle, $edittime );
1544                         // Try the master if this thread may have just added it.
1545                         // This could be abstracted into a Revision method, but we don't want
1546                         // to encourage loading of revisions by timestamp.
1547                         if ( !$rev
1548                                 && $lb->getServerCount() > 1
1549                                 && $lb->hasOrMadeRecentMasterChanges()
1550                         ) {
1551                                 $dbw = $lb->getConnection( DB_MASTER );
1552                                 $rev = Revision::loadFromTimestamp( $dbw, $this->mTitle, $edittime );
1553                         }
1554                         if ( $rev ) {
1555                                 $baseRevId = $rev->getId();
1556                         }
1557                 }
1558
1559                 return $this->replaceSectionAtRev( $sectionId, $sectionContent, $sectionTitle, $baseRevId );
1560         }
1561
1562         /**
1563          * @param string|int|null|bool $sectionId Section identifier as a number or string
1564          * (e.g. 0, 1 or 'T-1'), null/false or an empty string for the whole page
1565          * or 'new' for a new section.
1566          * @param Content $sectionContent New content of the section.
1567          * @param string $sectionTitle New section's subject, only if $section is "new".
1568          * @param int|null $baseRevId
1569          *
1570          * @throws MWException
1571          * @return Content|null New complete article content, or null if error.
1572          *
1573          * @since 1.24
1574          */
1575         public function replaceSectionAtRev( $sectionId, Content $sectionContent,
1576                 $sectionTitle = '', $baseRevId = null
1577         ) {
1578                 if ( strval( $sectionId ) === '' ) {
1579                         // Whole-page edit; let the whole text through
1580                         $newContent = $sectionContent;
1581                 } else {
1582                         if ( !$this->supportsSections() ) {
1583                                 throw new MWException( "sections not supported for content model " .
1584                                         $this->getContentHandler()->getModelID() );
1585                         }
1586
1587                         // T32711: always use current version when adding a new section
1588                         if ( is_null( $baseRevId ) || $sectionId === 'new' ) {
1589                                 $oldContent = $this->getContent();
1590                         } else {
1591                                 $rev = Revision::newFromId( $baseRevId );
1592                                 if ( !$rev ) {
1593                                         wfDebug( __METHOD__ . " asked for bogus section (page: " .
1594                                                 $this->getId() . "; section: $sectionId)\n" );
1595                                         return null;
1596                                 }
1597
1598                                 $oldContent = $rev->getContent();
1599                         }
1600
1601                         if ( !$oldContent ) {
1602                                 wfDebug( __METHOD__ . ": no page text\n" );
1603                                 return null;
1604                         }
1605
1606                         $newContent = $oldContent->replaceSection( $sectionId, $sectionContent, $sectionTitle );
1607                 }
1608
1609                 return $newContent;
1610         }
1611
1612         /**
1613          * Check flags and add EDIT_NEW or EDIT_UPDATE to them as needed.
1614          *
1615          * @deprecated since 1.32, use exists() instead, or simply omit the EDIT_UPDATE
1616          * and EDIT_NEW flags. To protect against race conditions, use PageUpdater::grabParentRevision.
1617          *
1618          * @param int $flags
1619          * @return int Updated $flags
1620          */
1621         public function checkFlags( $flags ) {
1622                 if ( !( $flags & EDIT_NEW ) && !( $flags & EDIT_UPDATE ) ) {
1623                         if ( $this->exists() ) {
1624                                 $flags |= EDIT_UPDATE;
1625                         } else {
1626                                 $flags |= EDIT_NEW;
1627                         }
1628                 }
1629
1630                 return $flags;
1631         }
1632
1633         /**
1634          * @return DerivedPageDataUpdater
1635          */
1636         private function newDerivedDataUpdater() {
1637                 global $wgRCWatchCategoryMembership, $wgArticleCountMethod;
1638
1639                 $derivedDataUpdater = new DerivedPageDataUpdater(
1640                         $this, // NOTE: eventually, PageUpdater should not know about WikiPage
1641                         $this->getRevisionStore(),
1642                         $this->getRevisionRenderer(),
1643                         $this->getParserCache(),
1644                         JobQueueGroup::singleton(),
1645                         MessageCache::singleton(),
1646                         MediaWikiServices::getInstance()->getContentLanguage(),
1647                         LoggerFactory::getInstance( 'SaveParse' )
1648                 );
1649
1650                 $derivedDataUpdater->setRcWatchCategoryMembership( $wgRCWatchCategoryMembership );
1651                 $derivedDataUpdater->setArticleCountMethod( $wgArticleCountMethod );
1652
1653                 return $derivedDataUpdater;
1654         }
1655
1656         /**
1657          * Returns a DerivedPageDataUpdater for use with the given target revision or new content.
1658          * This method attempts to re-use the same DerivedPageDataUpdater instance for subsequent calls.
1659          * The parameters passed to this method are used to ensure that the DerivedPageDataUpdater
1660          * returned matches that caller's expectations, allowing an existing instance to be re-used
1661          * if the given parameters match that instance's internal state according to
1662          * DerivedPageDataUpdater::isReusableFor(), and creating a new instance of the parameters do not
1663          * match the existign one.
1664          *
1665          * If neither $forRevision nor $forUpdate is given, a new DerivedPageDataUpdater is always
1666          * created, replacing any DerivedPageDataUpdater currently cached.
1667          *
1668          * MCR migration note: this replaces WikiPage::prepareContentForEdit.
1669          *
1670          * @since 1.32
1671          *
1672          * @param User|null $forUser The user that will be used for, or was used for, PST.
1673          * @param RevisionRecord|null $forRevision The revision created by the edit for which
1674          *        to perform updates, if the edit was already saved.
1675          * @param RevisionSlotsUpdate|null $forUpdate The new content to be saved by the edit (pre PST),
1676          *        if the edit was not yet saved.
1677          * @param bool $forEdit Only re-use if the cached DerivedPageDataUpdater has the current
1678          *       revision as the edit's parent revision. This ensures that the same
1679          *       DerivedPageDataUpdater cannot be re-used for two consecutive edits.
1680          *
1681          * @return DerivedPageDataUpdater
1682          */
1683         private function getDerivedDataUpdater(
1684                 User $forUser = null,
1685                 RevisionRecord $forRevision = null,
1686                 RevisionSlotsUpdate $forUpdate = null,
1687                 $forEdit = false
1688         ) {
1689                 if ( !$forRevision && !$forUpdate ) {
1690                         // NOTE: can't re-use an existing derivedDataUpdater if we don't know what the caller is
1691                         // going to use it with.
1692                         $this->derivedDataUpdater = null;
1693                 }
1694
1695                 if ( $this->derivedDataUpdater && !$this->derivedDataUpdater->isContentPrepared() ) {
1696                         // NOTE: can't re-use an existing derivedDataUpdater if other code that has a reference
1697                         // to it did not yet initialize it, because we don't know what data it will be
1698                         // initialized with.
1699                         $this->derivedDataUpdater = null;
1700                 }
1701
1702                 // XXX: It would be nice to have an LRU cache instead of trying to re-use a single instance.
1703                 // However, there is no good way to construct a cache key. We'd need to check against all
1704                 // cached instances.
1705
1706                 if ( $this->derivedDataUpdater
1707                         && !$this->derivedDataUpdater->isReusableFor(
1708                                 $forUser,
1709                                 $forRevision,
1710                                 $forUpdate,
1711                                 $forEdit ? $this->getLatest() : null
1712                         )
1713                 ) {
1714                         $this->derivedDataUpdater = null;
1715                 }
1716
1717                 if ( !$this->derivedDataUpdater ) {
1718                         $this->derivedDataUpdater = $this->newDerivedDataUpdater();
1719                 }
1720
1721                 return $this->derivedDataUpdater;
1722         }
1723
1724         /**
1725          * Returns a PageUpdater for creating new revisions on this page (or creating the page).
1726          *
1727          * The PageUpdater can also be used to detect the need for edit conflict resolution,
1728          * and to protected such conflict resolution from concurrent edits using a check-and-set
1729          * mechanism.
1730          *
1731          * @since 1.32
1732          *
1733          * @param User $user
1734          * @param RevisionSlotsUpdate|null $forUpdate If given, allows any cached ParserOutput
1735          *        that may already have been returned via getDerivedDataUpdater to be re-used.
1736          *
1737          * @return PageUpdater
1738          */
1739         public function newPageUpdater( User $user, RevisionSlotsUpdate $forUpdate = null ) {
1740                 global $wgAjaxEditStash, $wgUseAutomaticEditSummaries, $wgPageCreationLog;
1741
1742                 $pageUpdater = new PageUpdater(
1743                         $user,
1744                         $this, // NOTE: eventually, PageUpdater should not know about WikiPage
1745                         $this->getDerivedDataUpdater( $user, null, $forUpdate, true ),
1746                         $this->getDBLoadBalancer(),
1747                         $this->getRevisionStore()
1748                 );
1749
1750                 $pageUpdater->setUsePageCreationLog( $wgPageCreationLog );
1751                 $pageUpdater->setAjaxEditStash( $wgAjaxEditStash );
1752                 $pageUpdater->setUseAutomaticEditSummaries( $wgUseAutomaticEditSummaries );
1753
1754                 return $pageUpdater;
1755         }
1756
1757         /**
1758          * Change an existing article or create a new article. Updates RC and all necessary caches,
1759          * optionally via the deferred update array.
1760          *
1761          * @deprecated since 1.32, use PageUpdater::saveRevision instead. Note that the new method
1762          * expects callers to take care of checking EDIT_MINOR against the minoredit right, and to
1763          * apply the autopatrol right as appropriate.
1764          *
1765          * @param Content $content New content
1766          * @param string|CommentStoreComment $summary Edit summary
1767          * @param int $flags Bitfield:
1768          *      EDIT_NEW
1769          *          Article is known or assumed to be non-existent, create a new one
1770          *      EDIT_UPDATE
1771          *          Article is known or assumed to be pre-existing, update it
1772          *      EDIT_MINOR
1773          *          Mark this edit minor, if the user is allowed to do so
1774          *      EDIT_SUPPRESS_RC
1775          *          Do not log the change in recentchanges
1776          *      EDIT_FORCE_BOT
1777          *          Mark the edit a "bot" edit regardless of user rights
1778          *      EDIT_AUTOSUMMARY
1779          *          Fill in blank summaries with generated text where possible
1780          *      EDIT_INTERNAL
1781          *          Signal that the page retrieve/save cycle happened entirely in this request.
1782          *
1783          * If neither EDIT_NEW nor EDIT_UPDATE is specified, the status of the
1784          * article will be detected. If EDIT_UPDATE is specified and the article
1785          * doesn't exist, the function will return an edit-gone-missing error. If
1786          * EDIT_NEW is specified and the article does exist, an edit-already-exists
1787          * error will be returned. These two conditions are also possible with
1788          * auto-detection due to MediaWiki's performance-optimised locking strategy.
1789          *
1790          * @param bool|int $originalRevId: The ID of an original revision that the edit
1791          * restores or repeats. The new revision is expected to have the exact same content as
1792          * the given original revision. This is used with rollbacks and with dummy "null" revisions
1793          * which are created to record things like page moves.
1794          * @param User|null $user The user doing the edit
1795          * @param string|null $serialFormat IGNORED.
1796          * @param array|null $tags Change tags to apply to this edit
1797          * Callers are responsible for permission checks
1798          * (with ChangeTags::canAddTagsAccompanyingChange)
1799          * @param Int $undidRevId Id of revision that was undone or 0
1800          *
1801          * @throws MWException
1802          * @return Status Possible errors:
1803          *     edit-hook-aborted: The ArticleSave hook aborted the edit but didn't
1804          *       set the fatal flag of $status.
1805          *     edit-gone-missing: In update mode, but the article didn't exist.
1806          *     edit-conflict: In update mode, the article changed unexpectedly.
1807          *     edit-no-change: Warning that the text was the same as before.
1808          *     edit-already-exists: In creation mode, but the article already exists.
1809          *
1810          *  Extensions may define additional errors.
1811          *
1812          *  $return->value will contain an associative array with members as follows:
1813          *     new: Boolean indicating if the function attempted to create a new article.
1814          *     revision: The revision object for the inserted revision, or null.
1815          *
1816          * @since 1.21
1817          * @throws MWException
1818          */
1819         public function doEditContent(
1820                 Content $content, $summary, $flags = 0, $originalRevId = false,
1821                 User $user = null, $serialFormat = null, $tags = [], $undidRevId = 0
1822         ) {
1823                 global $wgUser, $wgUseNPPatrol, $wgUseRCPatrol;
1824
1825                 if ( !( $summary instanceof CommentStoreComment ) ) {
1826                         $summary = CommentStoreComment::newUnsavedComment( trim( $summary ) );
1827                 }
1828
1829                 if ( !$user ) {
1830                         $user = $wgUser;
1831                 }
1832
1833                 // TODO: this check is here for backwards-compatibility with 1.31 behavior.
1834                 // Checking the minoredit right should be done in the same place the 'bot' right is
1835                 // checked for the EDIT_FORCE_BOT flag, which is currently in EditPage::attemptSave.
1836                 if ( ( $flags & EDIT_MINOR ) && !$user->isAllowed( 'minoredit' ) ) {
1837                         $flags = ( $flags & ~EDIT_MINOR );
1838                 }
1839
1840                 $slotsUpdate = new RevisionSlotsUpdate();
1841                 $slotsUpdate->modifyContent( 'main', $content );
1842
1843                 // NOTE: while doEditContent() executes, callbacks to getDerivedDataUpdater and
1844                 // prepareContentForEdit will generally use the DerivedPageDataUpdater that is also
1845                 // used by this PageUpdater. However, there is no guarantee for this.
1846                 $updater = $this->newPageUpdater( $user, $slotsUpdate );
1847                 $updater->setContent( 'main', $content );
1848                 $updater->setOriginalRevisionId( $originalRevId );
1849                 $updater->setUndidRevisionId( $undidRevId );
1850
1851                 $needsPatrol = $wgUseRCPatrol || ( $wgUseNPPatrol && !$this->exists() );
1852
1853                 // TODO: this logic should not be in the storage layer, it's here for compatibility
1854                 // with 1.31 behavior. Applying the 'autopatrol' right should be done in the same
1855                 // place the 'bot' right is handled, which is currently in EditPage::attemptSave.
1856                 if ( $needsPatrol && $this->getTitle()->userCan( 'autopatrol', $user ) ) {
1857                         $updater->setRcPatrolStatus( RecentChange::PRC_AUTOPATROLLED );
1858                 }
1859
1860                 $updater->addTags( $tags );
1861
1862                 $revRec = $updater->saveRevision(
1863                         $summary,
1864                         $flags
1865                 );
1866
1867                 // $revRec will be null if the edit failed, or if no new revision was created because
1868                 // the content did not change.
1869                 if ( $revRec ) {
1870                         // update cached fields
1871                         // TODO: this is currently redundant to what is done in updateRevisionOn.
1872                         // But updateRevisionOn() should move into PageStore, and then this will be needed.
1873                         $this->setLastEdit( new Revision( $revRec ) ); // TODO: use RevisionRecord
1874                         $this->mLatest = $revRec->getId();
1875                 }
1876
1877                 return $updater->getStatus();
1878         }
1879
1880         /**
1881          * Get parser options suitable for rendering the primary article wikitext
1882          *
1883          * @see ParserOptions::newCanonical
1884          *
1885          * @param IContextSource|User|string $context One of the following:
1886          *        - IContextSource: Use the User and the Language of the provided
1887          *          context
1888          *        - User: Use the provided User object and $wgLang for the language,
1889          *          so use an IContextSource object if possible.
1890          *        - 'canonical': Canonical options (anonymous user with default
1891          *          preferences and content language).
1892          * @return ParserOptions
1893          */
1894         public function makeParserOptions( $context ) {
1895                 $options = ParserOptions::newCanonical( $context );
1896
1897                 if ( $this->getTitle()->isConversionTable() ) {
1898                         // @todo ConversionTable should become a separate content model, so
1899                         // we don't need special cases like this one.
1900                         $options->disableContentConversion();
1901                 }
1902
1903                 return $options;
1904         }
1905
1906         /**
1907          * Prepare content which is about to be saved.
1908          *
1909          * Prior to 1.30, this returned a stdClass.
1910          *
1911          * @deprecated since 1.32, use getDerivedDataUpdater instead.
1912          *
1913          * @param Content $content
1914          * @param Revision|RevisionRecord|int|null $revision Revision object.
1915          *        For backwards compatibility, a revision ID is also accepted,
1916          *        but this is deprecated.
1917          *        Used with vary-revision or vary-revision-id.
1918          * @param User|null $user
1919          * @param string|null $serialFormat IGNORED
1920          * @param bool $useCache Check shared prepared edit cache
1921          *
1922          * @return PreparedEdit
1923          *
1924          * @since 1.21
1925          */
1926         public function prepareContentForEdit(
1927                 Content $content,
1928                 $revision = null,
1929                 User $user = null,
1930                 $serialFormat = null,
1931                 $useCache = true
1932         ) {
1933                 global $wgUser;
1934
1935                 if ( !$user ) {
1936                         $user = $wgUser;
1937                 }
1938
1939                 if ( !is_object( $revision ) ) {
1940                         $revid = $revision;
1941                         // This code path is deprecated, and nothing is known to
1942                         // use it, so performance here shouldn't be a worry.
1943                         if ( $revid !== null ) {
1944                                 wfDeprecated( __METHOD__ . ' with $revision = revision ID', '1.25' );
1945                                 $store = $this->getRevisionStore();
1946                                 $revision = $store->getRevisionById( $revid, Revision::READ_LATEST );
1947                         } else {
1948                                 $revision = null;
1949                         }
1950                 } elseif ( $revision instanceof Revision ) {
1951                         $revision = $revision->getRevisionRecord();
1952                 }
1953
1954                 $slots = RevisionSlotsUpdate::newFromContent( [ 'main' => $content ] );
1955                 $updater = $this->getDerivedDataUpdater( $user, $revision, $slots );
1956
1957                 if ( !$updater->isUpdatePrepared() ) {
1958                         $updater->prepareContent( $user, $slots, $useCache );
1959
1960                         if ( $revision ) {
1961                                 $updater->prepareUpdate( $revision );
1962                         }
1963                 }
1964
1965                 return $updater->getPreparedEdit();
1966         }
1967
1968         /**
1969          * Do standard deferred updates after page edit.
1970          * Update links tables, site stats, search index and message cache.
1971          * Purges pages that include this page if the text was changed here.
1972          * Every 100th edit, prune the recent changes table.
1973          *
1974          * @deprecated since 1.32, use PageUpdater::doUpdates instead.
1975          *
1976          * @param Revision $revision
1977          * @param User $user User object that did the revision
1978          * @param array $options Array of options, following indexes are used:
1979          * - changed: bool, whether the revision changed the content (default true)
1980          * - created: bool, whether the revision created the page (default false)
1981          * - moved: bool, whether the page was moved (default false)
1982          * - restored: bool, whether the page was undeleted (default false)
1983          * - oldrevision: Revision object for the pre-update revision (default null)
1984          * - oldcountable: bool, null, or string 'no-change' (default null):
1985          *   - bool: whether the page was counted as an article before that
1986          *     revision, only used in changed is true and created is false
1987          *   - null: if created is false, don't update the article count; if created
1988          *     is true, do update the article count
1989          *   - 'no-change': don't update the article count, ever
1990          */
1991         public function doEditUpdates( Revision $revision, User $user, array $options = [] ) {
1992                 $revision = $revision->getRevisionRecord();
1993
1994                 $updater = $this->getDerivedDataUpdater( $user, $revision );
1995
1996                 $updater->prepareUpdate( $revision, $options );
1997
1998                 $updater->doUpdates();
1999         }
2000
2001         /**
2002          * Update the article's restriction field, and leave a log entry.
2003          * This works for protection both existing and non-existing pages.
2004          *
2005          * @param array $limit Set of restriction keys
2006          * @param array $expiry Per restriction type expiration
2007          * @param int &$cascade Set to false if cascading protection isn't allowed.
2008          * @param string $reason
2009          * @param User $user The user updating the restrictions
2010          * @param string|string[]|null $tags Change tags to add to the pages and protection log entries
2011          *   ($user should be able to add the specified tags before this is called)
2012          * @return Status Status object; if action is taken, $status->value is the log_id of the
2013          *   protection log entry.
2014          */
2015         public function doUpdateRestrictions( array $limit, array $expiry,
2016                 &$cascade, $reason, User $user, $tags = null
2017         ) {
2018                 global $wgCascadingRestrictionLevels;
2019
2020                 if ( wfReadOnly() ) {
2021                         return Status::newFatal( wfMessage( 'readonlytext', wfReadOnlyReason() ) );
2022                 }
2023
2024                 $this->loadPageData( 'fromdbmaster' );
2025                 $restrictionTypes = $this->mTitle->getRestrictionTypes();
2026                 $id = $this->getId();
2027
2028                 if ( !$cascade ) {
2029                         $cascade = false;
2030                 }
2031
2032                 // Take this opportunity to purge out expired restrictions
2033                 Title::purgeExpiredRestrictions();
2034
2035                 // @todo: Same limitations as described in ProtectionForm.php (line 37);
2036                 // we expect a single selection, but the schema allows otherwise.
2037                 $isProtected = false;
2038                 $protect = false;
2039                 $changed = false;
2040
2041                 $dbw = wfGetDB( DB_MASTER );
2042
2043                 foreach ( $restrictionTypes as $action ) {
2044                         if ( !isset( $expiry[$action] ) || $expiry[$action] === $dbw->getInfinity() ) {
2045                                 $expiry[$action] = 'infinity';
2046                         }
2047                         if ( !isset( $limit[$action] ) ) {
2048                                 $limit[$action] = '';
2049                         } elseif ( $limit[$action] != '' ) {
2050                                 $protect = true;
2051                         }
2052
2053                         // Get current restrictions on $action
2054                         $current = implode( '', $this->mTitle->getRestrictions( $action ) );
2055                         if ( $current != '' ) {
2056                                 $isProtected = true;
2057                         }
2058
2059                         if ( $limit[$action] != $current ) {
2060                                 $changed = true;
2061                         } elseif ( $limit[$action] != '' ) {
2062                                 // Only check expiry change if the action is actually being
2063                                 // protected, since expiry does nothing on an not-protected
2064                                 // action.
2065                                 if ( $this->mTitle->getRestrictionExpiry( $action ) != $expiry[$action] ) {
2066                                         $changed = true;
2067                                 }
2068                         }
2069                 }
2070
2071                 if ( !$changed && $protect && $this->mTitle->areRestrictionsCascading() != $cascade ) {
2072                         $changed = true;
2073                 }
2074
2075                 // If nothing has changed, do nothing
2076                 if ( !$changed ) {
2077                         return Status::newGood();
2078                 }
2079
2080                 if ( !$protect ) { // No protection at all means unprotection
2081                         $revCommentMsg = 'unprotectedarticle-comment';
2082                         $logAction = 'unprotect';
2083                 } elseif ( $isProtected ) {
2084                         $revCommentMsg = 'modifiedarticleprotection-comment';
2085                         $logAction = 'modify';
2086                 } else {
2087                         $revCommentMsg = 'protectedarticle-comment';
2088                         $logAction = 'protect';
2089                 }
2090
2091                 $logRelationsValues = [];
2092                 $logRelationsField = null;
2093                 $logParamsDetails = [];
2094
2095                 // Null revision (used for change tag insertion)
2096                 $nullRevision = null;
2097
2098                 if ( $id ) { // Protection of existing page
2099                         // Avoid PHP 7.1 warning of passing $this by reference
2100                         $wikiPage = $this;
2101
2102                         if ( !Hooks::run( 'ArticleProtect', [ &$wikiPage, &$user, $limit, $reason ] ) ) {
2103                                 return Status::newGood();
2104                         }
2105
2106                         // Only certain restrictions can cascade...
2107                         $editrestriction = isset( $limit['edit'] )
2108                                 ? [ $limit['edit'] ]
2109                                 : $this->mTitle->getRestrictions( 'edit' );
2110                         foreach ( array_keys( $editrestriction, 'sysop' ) as $key ) {
2111                                 $editrestriction[$key] = 'editprotected'; // backwards compatibility
2112                         }
2113                         foreach ( array_keys( $editrestriction, 'autoconfirmed' ) as $key ) {
2114                                 $editrestriction[$key] = 'editsemiprotected'; // backwards compatibility
2115                         }
2116
2117                         $cascadingRestrictionLevels = $wgCascadingRestrictionLevels;
2118                         foreach ( array_keys( $cascadingRestrictionLevels, 'sysop' ) as $key ) {
2119                                 $cascadingRestrictionLevels[$key] = 'editprotected'; // backwards compatibility
2120                         }
2121                         foreach ( array_keys( $cascadingRestrictionLevels, 'autoconfirmed' ) as $key ) {
2122                                 $cascadingRestrictionLevels[$key] = 'editsemiprotected'; // backwards compatibility
2123                         }
2124
2125                         // The schema allows multiple restrictions
2126                         if ( !array_intersect( $editrestriction, $cascadingRestrictionLevels ) ) {
2127                                 $cascade = false;
2128                         }
2129
2130                         // insert null revision to identify the page protection change as edit summary
2131                         $latest = $this->getLatest();
2132                         $nullRevision = $this->insertProtectNullRevision(
2133                                 $revCommentMsg,
2134                                 $limit,
2135                                 $expiry,
2136                                 $cascade,
2137                                 $reason,
2138                                 $user
2139                         );
2140
2141                         if ( $nullRevision === null ) {
2142                                 return Status::newFatal( 'no-null-revision', $this->mTitle->getPrefixedText() );
2143                         }
2144
2145                         $logRelationsField = 'pr_id';
2146
2147                         // Update restrictions table
2148                         foreach ( $limit as $action => $restrictions ) {
2149                                 $dbw->delete(
2150                                         'page_restrictions',
2151                                         [
2152                                                 'pr_page' => $id,
2153                                                 'pr_type' => $action
2154                                         ],
2155                                         __METHOD__
2156                                 );
2157                                 if ( $restrictions != '' ) {
2158                                         $cascadeValue = ( $cascade && $action == 'edit' ) ? 1 : 0;
2159                                         $dbw->insert(
2160                                                 'page_restrictions',
2161                                                 [
2162                                                         'pr_page' => $id,
2163                                                         'pr_type' => $action,
2164                                                         'pr_level' => $restrictions,
2165                                                         'pr_cascade' => $cascadeValue,
2166                                                         'pr_expiry' => $dbw->encodeExpiry( $expiry[$action] )
2167                                                 ],
2168                                                 __METHOD__
2169                                         );
2170                                         $logRelationsValues[] = $dbw->insertId();
2171                                         $logParamsDetails[] = [
2172                                                 'type' => $action,
2173                                                 'level' => $restrictions,
2174                                                 'expiry' => $expiry[$action],
2175                                                 'cascade' => (bool)$cascadeValue,
2176                                         ];
2177                                 }
2178                         }
2179
2180                         // Clear out legacy restriction fields
2181                         $dbw->update(
2182                                 'page',
2183                                 [ 'page_restrictions' => '' ],
2184                                 [ 'page_id' => $id ],
2185                                 __METHOD__
2186                         );
2187
2188                         // Avoid PHP 7.1 warning of passing $this by reference
2189                         $wikiPage = $this;
2190
2191                         Hooks::run( 'NewRevisionFromEditComplete',
2192                                 [ $this, $nullRevision, $latest, $user ] );
2193                         Hooks::run( 'ArticleProtectComplete', [ &$wikiPage, &$user, $limit, $reason ] );
2194                 } else { // Protection of non-existing page (also known as "title protection")
2195                         // Cascade protection is meaningless in this case
2196                         $cascade = false;
2197
2198                         if ( $limit['create'] != '' ) {
2199                                 $commentFields = CommentStore::getStore()->insert( $dbw, 'pt_reason', $reason );
2200                                 $dbw->replace( 'protected_titles',
2201                                         [ [ 'pt_namespace', 'pt_title' ] ],
2202                                         [
2203                                                 'pt_namespace' => $this->mTitle->getNamespace(),
2204                                                 'pt_title' => $this->mTitle->getDBkey(),
2205                                                 'pt_create_perm' => $limit['create'],
2206                                                 'pt_timestamp' => $dbw->timestamp(),
2207                                                 'pt_expiry' => $dbw->encodeExpiry( $expiry['create'] ),
2208                                                 'pt_user' => $user->getId(),
2209                                         ] + $commentFields, __METHOD__
2210                                 );
2211                                 $logParamsDetails[] = [
2212                                         'type' => 'create',
2213                                         'level' => $limit['create'],
2214                                         'expiry' => $expiry['create'],
2215                                 ];
2216                         } else {
2217                                 $dbw->delete( 'protected_titles',
2218                                         [
2219                                                 'pt_namespace' => $this->mTitle->getNamespace(),
2220                                                 'pt_title' => $this->mTitle->getDBkey()
2221                                         ], __METHOD__
2222                                 );
2223                         }
2224                 }
2225
2226                 $this->mTitle->flushRestrictions();
2227                 InfoAction::invalidateCache( $this->mTitle );
2228
2229                 if ( $logAction == 'unprotect' ) {
2230                         $params = [];
2231                 } else {
2232                         $protectDescriptionLog = $this->protectDescriptionLog( $limit, $expiry );
2233                         $params = [
2234                                 '4::description' => $protectDescriptionLog, // parameter for IRC
2235                                 '5:bool:cascade' => $cascade,
2236                                 'details' => $logParamsDetails, // parameter for localize and api
2237                         ];
2238                 }
2239
2240                 // Update the protection log
2241                 $logEntry = new ManualLogEntry( 'protect', $logAction );
2242                 $logEntry->setTarget( $this->mTitle );
2243                 $logEntry->setComment( $reason );
2244                 $logEntry->setPerformer( $user );
2245                 $logEntry->setParameters( $params );
2246                 if ( !is_null( $nullRevision ) ) {
2247                         $logEntry->setAssociatedRevId( $nullRevision->getId() );
2248                 }
2249                 $logEntry->setTags( $tags );
2250                 if ( $logRelationsField !== null && count( $logRelationsValues ) ) {
2251                         $logEntry->setRelations( [ $logRelationsField => $logRelationsValues ] );
2252                 }
2253                 $logId = $logEntry->insert();
2254                 $logEntry->publish( $logId );
2255
2256                 return Status::newGood( $logId );
2257         }
2258
2259         /**
2260          * Insert a new null revision for this page.
2261          *
2262          * @param string $revCommentMsg Comment message key for the revision
2263          * @param array $limit Set of restriction keys
2264          * @param array $expiry Per restriction type expiration
2265          * @param int $cascade Set to false if cascading protection isn't allowed.
2266          * @param string $reason
2267          * @param User|null $user
2268          * @return Revision|null Null on error
2269          */
2270         public function insertProtectNullRevision( $revCommentMsg, array $limit,
2271                 array $expiry, $cascade, $reason, $user = null
2272         ) {
2273                 $dbw = wfGetDB( DB_MASTER );
2274
2275                 // Prepare a null revision to be added to the history
2276                 $editComment = wfMessage(
2277                         $revCommentMsg,
2278                         $this->mTitle->getPrefixedText(),
2279                         $user ? $user->getName() : ''
2280                 )->inContentLanguage()->text();
2281                 if ( $reason ) {
2282                         $editComment .= wfMessage( 'colon-separator' )->inContentLanguage()->text() . $reason;
2283                 }
2284                 $protectDescription = $this->protectDescription( $limit, $expiry );
2285                 if ( $protectDescription ) {
2286                         $editComment .= wfMessage( 'word-separator' )->inContentLanguage()->text();
2287                         $editComment .= wfMessage( 'parentheses' )->params( $protectDescription )
2288                                 ->inContentLanguage()->text();
2289                 }
2290                 if ( $cascade ) {
2291                         $editComment .= wfMessage( 'word-separator' )->inContentLanguage()->text();
2292                         $editComment .= wfMessage( 'brackets' )->params(
2293                                 wfMessage( 'protect-summary-cascade' )->inContentLanguage()->text()
2294                         )->inContentLanguage()->text();
2295                 }
2296
2297                 $nullRev = Revision::newNullRevision( $dbw, $this->getId(), $editComment, true, $user );
2298                 if ( $nullRev ) {
2299                         $nullRev->insertOn( $dbw );
2300
2301                         // Update page record and touch page
2302                         $oldLatest = $nullRev->getParentId();
2303                         $this->updateRevisionOn( $dbw, $nullRev, $oldLatest );
2304                 }
2305
2306                 return $nullRev;
2307         }
2308
2309         /**
2310          * @param string $expiry 14-char timestamp or "infinity", or false if the input was invalid
2311          * @return string
2312          */
2313         protected function formatExpiry( $expiry ) {
2314                 if ( $expiry != 'infinity' ) {
2315                         $contLang = MediaWikiServices::getInstance()->getContentLanguage();
2316                         return wfMessage(
2317                                 'protect-expiring',
2318                                 $contLang->timeanddate( $expiry, false, false ),
2319                                 $contLang->date( $expiry, false, false ),
2320                                 $contLang->time( $expiry, false, false )
2321                         )->inContentLanguage()->text();
2322                 } else {
2323                         return wfMessage( 'protect-expiry-indefinite' )
2324                                 ->inContentLanguage()->text();
2325                 }
2326         }
2327
2328         /**
2329          * Builds the description to serve as comment for the edit.
2330          *
2331          * @param array $limit Set of restriction keys
2332          * @param array $expiry Per restriction type expiration
2333          * @return string
2334          */
2335         public function protectDescription( array $limit, array $expiry ) {
2336                 $protectDescription = '';
2337
2338                 foreach ( array_filter( $limit ) as $action => $restrictions ) {
2339                         # $action is one of $wgRestrictionTypes = [ 'create', 'edit', 'move', 'upload' ].
2340                         # All possible message keys are listed here for easier grepping:
2341                         # * restriction-create
2342                         # * restriction-edit
2343                         # * restriction-move
2344                         # * restriction-upload
2345                         $actionText = wfMessage( 'restriction-' . $action )->inContentLanguage()->text();
2346                         # $restrictions is one of $wgRestrictionLevels = [ '', 'autoconfirmed', 'sysop' ],
2347                         # with '' filtered out. All possible message keys are listed below:
2348                         # * protect-level-autoconfirmed
2349                         # * protect-level-sysop
2350                         $restrictionsText = wfMessage( 'protect-level-' . $restrictions )
2351                                 ->inContentLanguage()->text();
2352
2353                         $expiryText = $this->formatExpiry( $expiry[$action] );
2354
2355                         if ( $protectDescription !== '' ) {
2356                                 $protectDescription .= wfMessage( 'word-separator' )->inContentLanguage()->text();
2357                         }
2358                         $protectDescription .= wfMessage( 'protect-summary-desc' )
2359                                 ->params( $actionText, $restrictionsText, $expiryText )
2360                                 ->inContentLanguage()->text();
2361                 }
2362
2363                 return $protectDescription;
2364         }
2365
2366         /**
2367          * Builds the description to serve as comment for the log entry.
2368          *
2369          * Some bots may parse IRC lines, which are generated from log entries which contain plain
2370          * protect description text. Keep them in old format to avoid breaking compatibility.
2371          * TODO: Fix protection log to store structured description and format it on-the-fly.
2372          *
2373          * @param array $limit Set of restriction keys
2374          * @param array $expiry Per restriction type expiration
2375          * @return string
2376          */
2377         public function protectDescriptionLog( array $limit, array $expiry ) {
2378                 $protectDescriptionLog = '';
2379
2380                 $dirMark = MediaWikiServices::getInstance()->getContentLanguage()->getDirMark();
2381                 foreach ( array_filter( $limit ) as $action => $restrictions ) {
2382                         $expiryText = $this->formatExpiry( $expiry[$action] );
2383                         $protectDescriptionLog .=
2384                                 $dirMark .
2385                                 "[$action=$restrictions] ($expiryText)";
2386                 }
2387
2388                 return trim( $protectDescriptionLog );
2389         }
2390
2391         /**
2392          * Take an array of page restrictions and flatten it to a string
2393          * suitable for insertion into the page_restrictions field.
2394          *
2395          * @param string[] $limit
2396          *
2397          * @throws MWException
2398          * @return string
2399          */
2400         protected static function flattenRestrictions( $limit ) {
2401                 if ( !is_array( $limit ) ) {
2402                         throw new MWException( __METHOD__ . ' given non-array restriction set' );
2403                 }
2404
2405                 $bits = [];
2406                 ksort( $limit );
2407
2408                 foreach ( array_filter( $limit ) as $action => $restrictions ) {
2409                         $bits[] = "$action=$restrictions";
2410                 }
2411
2412                 return implode( ':', $bits );
2413         }
2414
2415         /**
2416          * Same as doDeleteArticleReal(), but returns a simple boolean. This is kept around for
2417          * backwards compatibility, if you care about error reporting you should use
2418          * doDeleteArticleReal() instead.
2419          *
2420          * Deletes the article with database consistency, writes logs, purges caches
2421          *
2422          * @param string $reason Delete reason for deletion log
2423          * @param bool $suppress Suppress all revisions and log the deletion in
2424          *        the suppression log instead of the deletion log
2425          * @param int|null $u1 Unused
2426          * @param bool|null $u2 Unused
2427          * @param array|string &$error Array of errors to append to
2428          * @param User|null $user The deleting user
2429          * @return bool True if successful
2430          */
2431         public function doDeleteArticle(
2432                 $reason, $suppress = false, $u1 = null, $u2 = null, &$error = '', User $user = null
2433         ) {
2434                 $status = $this->doDeleteArticleReal( $reason, $suppress, $u1, $u2, $error, $user );
2435                 return $status->isGood();
2436         }
2437
2438         /**
2439          * Back-end article deletion
2440          * Deletes the article with database consistency, writes logs, purges caches
2441          *
2442          * @since 1.19
2443          *
2444          * @param string $reason Delete reason for deletion log
2445          * @param bool $suppress Suppress all revisions and log the deletion in
2446          *   the suppression log instead of the deletion log
2447          * @param int|null $u1 Unused
2448          * @param bool|null $u2 Unused
2449          * @param array|string &$error Array of errors to append to
2450          * @param User|null $deleter The deleting user
2451          * @param array $tags Tags to apply to the deletion action
2452          * @param string $logsubtype
2453          * @return Status Status object; if successful, $status->value is the log_id of the
2454          *   deletion log entry. If the page couldn't be deleted because it wasn't
2455          *   found, $status is a non-fatal 'cannotdelete' error
2456          */
2457         public function doDeleteArticleReal(
2458                 $reason, $suppress = false, $u1 = null, $u2 = null, &$error = '', User $deleter = null,
2459                 $tags = [], $logsubtype = 'delete'
2460         ) {
2461                 global $wgUser, $wgContentHandlerUseDB, $wgCommentTableSchemaMigrationStage,
2462                         $wgActorTableSchemaMigrationStage, $wgMultiContentRevisionSchemaMigrationStage;
2463
2464                 wfDebug( __METHOD__ . "\n" );
2465
2466                 $status = Status::newGood();
2467
2468                 if ( $this->mTitle->getDBkey() === '' ) {
2469                         $status->error( 'cannotdelete',
2470                                 wfEscapeWikiText( $this->getTitle()->getPrefixedText() ) );
2471                         return $status;
2472                 }
2473
2474                 // Avoid PHP 7.1 warning of passing $this by reference
2475                 $wikiPage = $this;
2476
2477                 $deleter = is_null( $deleter ) ? $wgUser : $deleter;
2478                 if ( !Hooks::run( 'ArticleDelete',
2479                         [ &$wikiPage, &$deleter, &$reason, &$error, &$status, $suppress ]
2480                 ) ) {
2481                         if ( $status->isOK() ) {
2482                                 // Hook aborted but didn't set a fatal status
2483                                 $status->fatal( 'delete-hook-aborted' );
2484                         }
2485                         return $status;
2486                 }
2487
2488                 $dbw = wfGetDB( DB_MASTER );
2489                 $dbw->startAtomic( __METHOD__ );
2490
2491                 $this->loadPageData( self::READ_LATEST );
2492                 $id = $this->getId();
2493                 // T98706: lock the page from various other updates but avoid using
2494                 // WikiPage::READ_LOCKING as that will carry over the FOR UPDATE to
2495                 // the revisions queries (which also JOIN on user). Only lock the page
2496                 // row and CAS check on page_latest to see if the trx snapshot matches.
2497                 $lockedLatest = $this->lockAndGetLatest();
2498                 if ( $id == 0 || $this->getLatest() != $lockedLatest ) {
2499                         $dbw->endAtomic( __METHOD__ );
2500                         // Page not there or trx snapshot is stale
2501                         $status->error( 'cannotdelete',
2502                                 wfEscapeWikiText( $this->getTitle()->getPrefixedText() ) );
2503                         return $status;
2504                 }
2505
2506                 // Given the lock above, we can be confident in the title and page ID values
2507                 $namespace = $this->getTitle()->getNamespace();
2508                 $dbKey = $this->getTitle()->getDBkey();
2509
2510                 // At this point we are now comitted to returning an OK
2511                 // status unless some DB query error or other exception comes up.
2512                 // This way callers don't have to call rollback() if $status is bad
2513                 // unless they actually try to catch exceptions (which is rare).
2514
2515                 // we need to remember the old content so we can use it to generate all deletion updates.
2516                 $revision = $this->getRevision();
2517                 try {
2518                         $content = $this->getContent( Revision::RAW );
2519                 } catch ( Exception $ex ) {
2520                         wfLogWarning( __METHOD__ . ': failed to load content during deletion! '
2521                                 . $ex->getMessage() );
2522
2523                         $content = null;
2524                 }
2525
2526                 $commentStore = CommentStore::getStore();
2527                 $actorMigration = ActorMigration::newMigration();
2528
2529                 $revQuery = Revision::getQueryInfo();
2530                 $bitfield = false;
2531
2532                 // Bitfields to further suppress the content
2533                 if ( $suppress ) {
2534                         $bitfield = Revision::SUPPRESSED_ALL;
2535                         $revQuery['fields'] = array_diff( $revQuery['fields'], [ 'rev_deleted' ] );
2536                 }
2537
2538                 // For now, shunt the revision data into the archive table.
2539                 // Text is *not* removed from the text table; bulk storage
2540                 // is left intact to avoid breaking block-compression or
2541                 // immutable storage schemes.
2542                 // In the future, we may keep revisions and mark them with
2543                 // the rev_deleted field, which is reserved for this purpose.
2544
2545                 // Lock rows in `revision` and its temp tables, but not any others.
2546                 // Note array_intersect() preserves keys from the first arg, and we're
2547                 // assuming $revQuery has `revision` primary and isn't using subtables
2548                 // for anything we care about.
2549                 $dbw->lockForUpdate(
2550                         array_intersect(
2551                                 $revQuery['tables'],
2552                                 [ 'revision', 'revision_comment_temp', 'revision_actor_temp' ]
2553                         ),
2554                         [ 'rev_page' => $id ],
2555                         __METHOD__,
2556                         [],
2557                         $revQuery['joins']
2558                 );
2559
2560                 // If SCHEMA_COMPAT_WRITE_OLD is set, also select all extra fields we still write,
2561                 // so we can copy it to the archive table.
2562                 // We know the fields exist, otherwise SCHEMA_COMPAT_WRITE_OLD could not function.
2563                 if ( $wgMultiContentRevisionSchemaMigrationStage & SCHEMA_COMPAT_WRITE_OLD ) {
2564                         $revQuery['fields'][] = 'rev_text_id';
2565
2566                         if ( $wgContentHandlerUseDB ) {
2567                                 $revQuery['fields'][] = 'rev_content_model';
2568                                 $revQuery['fields'][] = 'rev_content_format';
2569                         }
2570                 }
2571
2572                         // Get all of the page revisions
2573                 $res = $dbw->select(
2574                         $revQuery['tables'],
2575                         $revQuery['fields'],
2576                         [ 'rev_page' => $id ],
2577                         __METHOD__,
2578                         [],
2579                         $revQuery['joins']
2580                 );
2581
2582                 // Build their equivalent archive rows
2583                 $rowsInsert = [];
2584                 $revids = [];
2585
2586                 /** @var int[] Revision IDs of edits that were made by IPs */
2587                 $ipRevIds = [];
2588
2589                 foreach ( $res as $row ) {
2590                         $comment = $commentStore->getComment( 'rev_comment', $row );
2591                         $user = User::newFromAnyId( $row->rev_user, $row->rev_user_text, $row->rev_actor );
2592                         $rowInsert = [
2593                                 'ar_namespace'  => $namespace,
2594                                 'ar_title'      => $dbKey,
2595                                 'ar_timestamp'  => $row->rev_timestamp,
2596                                 'ar_minor_edit' => $row->rev_minor_edit,
2597                                 'ar_rev_id'     => $row->rev_id,
2598                                 'ar_parent_id'  => $row->rev_parent_id,
2599                                         /**
2600                                          * ar_text_id should probably not be written to when the multi content schema has
2601                                          * been migrated to (wgMultiContentRevisionSchemaMigrationStage) however there is no
2602                                          * default for the field in WMF production currently so we must keep writing
2603                                          * writing until a default of 0 is set.
2604                                          * Task: https://phabricator.wikimedia.org/T190148
2605                                          * Copying the value from the revision table should not lead to any issues for now.
2606                                          */
2607                                 'ar_len'        => $row->rev_len,
2608                                 'ar_page_id'    => $id,
2609                                 'ar_deleted'    => $suppress ? $bitfield : $row->rev_deleted,
2610                                 'ar_sha1'       => $row->rev_sha1,
2611                         ] + $commentStore->insert( $dbw, 'ar_comment', $comment )
2612                                 + $actorMigration->getInsertValues( $dbw, 'ar_user', $user );
2613
2614                         if ( $wgMultiContentRevisionSchemaMigrationStage & SCHEMA_COMPAT_WRITE_OLD ) {
2615                                 $rowInsert['ar_text_id'] = $row->rev_text_id;
2616
2617                                 if ( $wgContentHandlerUseDB ) {
2618                                         $rowInsert['ar_content_model'] = $row->rev_content_model;
2619                                         $rowInsert['ar_content_format'] = $row->rev_content_format;
2620                                 }
2621                         }
2622
2623                         $rowsInsert[] = $rowInsert;
2624                         $revids[] = $row->rev_id;
2625
2626                         // Keep track of IP edits, so that the corresponding rows can
2627                         // be deleted in the ip_changes table.
2628                         if ( (int)$row->rev_user === 0 && IP::isValid( $row->rev_user_text ) ) {
2629                                 $ipRevIds[] = $row->rev_id;
2630                         }
2631                 }
2632                 // Copy them into the archive table
2633                 $dbw->insert( 'archive', $rowsInsert, __METHOD__ );
2634                 // Save this so we can pass it to the ArticleDeleteComplete hook.
2635                 $archivedRevisionCount = $dbw->affectedRows();
2636
2637                 // Clone the title and wikiPage, so we have the information we need when
2638                 // we log and run the ArticleDeleteComplete hook.
2639                 $logTitle = clone $this->mTitle;
2640                 $wikiPageBeforeDelete = clone $this;
2641
2642                 // Now that it's safely backed up, delete it
2643                 $dbw->delete( 'page', [ 'page_id' => $id ], __METHOD__ );
2644                 $dbw->delete( 'revision', [ 'rev_page' => $id ], __METHOD__ );
2645                 if ( $wgCommentTableSchemaMigrationStage > MIGRATION_OLD ) {
2646                         $dbw->delete( 'revision_comment_temp', [ 'revcomment_rev' => $revids ], __METHOD__ );
2647                 }
2648                 if ( $wgActorTableSchemaMigrationStage > MIGRATION_OLD ) {
2649                         $dbw->delete( 'revision_actor_temp', [ 'revactor_rev' => $revids ], __METHOD__ );
2650                 }
2651
2652                 // Also delete records from ip_changes as applicable.
2653                 if ( count( $ipRevIds ) > 0 ) {
2654                         $dbw->delete( 'ip_changes', [ 'ipc_rev_id' => $ipRevIds ], __METHOD__ );
2655                 }
2656
2657                 // Log the deletion, if the page was suppressed, put it in the suppression log instead
2658                 $logtype = $suppress ? 'suppress' : 'delete';
2659
2660                 $logEntry = new ManualLogEntry( $logtype, $logsubtype );
2661                 $logEntry->setPerformer( $deleter );
2662                 $logEntry->setTarget( $logTitle );
2663                 $logEntry->setComment( $reason );
2664                 $logEntry->setTags( $tags );
2665                 $logid = $logEntry->insert();
2666
2667                 $dbw->onTransactionPreCommitOrIdle(
2668                         function () use ( $logEntry, $logid ) {
2669                                 // T58776: avoid deadlocks (especially from FileDeleteForm)
2670                                 $logEntry->publish( $logid );
2671                         },
2672                         __METHOD__
2673                 );
2674
2675                 $dbw->endAtomic( __METHOD__ );
2676
2677                 $this->doDeleteUpdates( $id, $content, $revision, $deleter );
2678
2679                 Hooks::run( 'ArticleDeleteComplete', [
2680                         &$wikiPageBeforeDelete,
2681                         &$deleter,
2682                         $reason,
2683                         $id,
2684                         $content,
2685                         $logEntry,
2686                         $archivedRevisionCount
2687                 ] );
2688                 $status->value = $logid;
2689
2690                 // Show log excerpt on 404 pages rather than just a link
2691                 $cache = MediaWikiServices::getInstance()->getMainObjectStash();
2692                 $key = $cache->makeKey( 'page-recent-delete', md5( $logTitle->getPrefixedText() ) );
2693                 $cache->set( $key, 1, $cache::TTL_DAY );
2694
2695                 return $status;
2696         }
2697
2698         /**
2699          * Lock the page row for this title+id and return page_latest (or 0)
2700          *
2701          * @return int Returns 0 if no row was found with this title+id
2702          * @since 1.27
2703          */
2704         public function lockAndGetLatest() {
2705                 return (int)wfGetDB( DB_MASTER )->selectField(
2706                         'page',
2707                         'page_latest',
2708                         [
2709                                 'page_id' => $this->getId(),
2710                                 // Typically page_id is enough, but some code might try to do
2711                                 // updates assuming the title is the same, so verify that
2712                                 'page_namespace' => $this->getTitle()->getNamespace(),
2713                                 'page_title' => $this->getTitle()->getDBkey()
2714                         ],
2715                         __METHOD__,
2716                         [ 'FOR UPDATE' ]
2717                 );
2718         }
2719
2720         /**
2721          * Do some database updates after deletion
2722          *
2723          * @param int $id The page_id value of the page being deleted
2724          * @param Content|null $content Optional page content to be used when determining
2725          *   the required updates. This may be needed because $this->getContent()
2726          *   may already return null when the page proper was deleted.
2727          * @param Revision|null $revision The latest page revision
2728          * @param User|null $user The user that caused the deletion
2729          */
2730         public function doDeleteUpdates(
2731                 $id, Content $content = null, Revision $revision = null, User $user = null
2732         ) {
2733                 try {
2734                         $countable = $this->isCountable();
2735                 } catch ( Exception $ex ) {
2736                         // fallback for deleting broken pages for which we cannot load the content for
2737                         // some reason. Note that doDeleteArticleReal() already logged this problem.
2738                         $countable = false;
2739                 }
2740
2741                 // Update site status
2742                 DeferredUpdates::addUpdate( SiteStatsUpdate::factory(
2743                         [ 'edits' => 1, 'articles' => -$countable, 'pages' => -1 ]
2744                 ) );
2745
2746                 // Delete pagelinks, update secondary indexes, etc
2747                 $updates = $this->getDeletionUpdates( $content );
2748                 foreach ( $updates as $update ) {
2749                         DeferredUpdates::addUpdate( $update );
2750                 }
2751
2752                 $causeAgent = $user ? $user->getName() : 'unknown';
2753                 // Reparse any pages transcluding this page
2754                 LinksUpdate::queueRecursiveJobsForTable(
2755                         $this->mTitle, 'templatelinks', 'delete-page', $causeAgent );
2756                 // Reparse any pages including this image
2757                 if ( $this->mTitle->getNamespace() == NS_FILE ) {
2758                         LinksUpdate::queueRecursiveJobsForTable(
2759                                 $this->mTitle, 'imagelinks', 'delete-page', $causeAgent );
2760                 }
2761
2762                 // Clear caches
2763                 self::onArticleDelete( $this->mTitle );
2764                 ResourceLoaderWikiModule::invalidateModuleCache(
2765                         $this->mTitle, $revision, null, wfWikiID()
2766                 );
2767
2768                 // Reset this object and the Title object
2769                 $this->loadFromRow( false, self::READ_LATEST );
2770
2771                 // Search engine
2772                 DeferredUpdates::addUpdate( new SearchUpdate( $id, $this->mTitle ) );
2773         }
2774
2775         /**
2776          * Roll back the most recent consecutive set of edits to a page
2777          * from the same user; fails if there are no eligible edits to
2778          * roll back to, e.g. user is the sole contributor. This function
2779          * performs permissions checks on $user, then calls commitRollback()
2780          * to do the dirty work
2781          *
2782          * @todo Separate the business/permission stuff out from backend code
2783          * @todo Remove $token parameter. Already verified by RollbackAction and ApiRollback.
2784          *
2785          * @param string $fromP Name of the user whose edits to rollback.
2786          * @param string $summary Custom summary. Set to default summary if empty.
2787          * @param string $token Rollback token.
2788          * @param bool $bot If true, mark all reverted edits as bot.
2789          *
2790          * @param array &$resultDetails Array contains result-specific array of additional values
2791          *    'alreadyrolled' : 'current' (rev)
2792          *    success        : 'summary' (str), 'current' (rev), 'target' (rev)
2793          *
2794          * @param User $user The user performing the rollback
2795          * @param array|null $tags Change tags to apply to the rollback
2796          * Callers are responsible for permission checks
2797          * (with ChangeTags::canAddTagsAccompanyingChange)
2798          *
2799          * @return array Array of errors, each error formatted as
2800          *   array(messagekey, param1, param2, ...).
2801          * On success, the array is empty.  This array can also be passed to
2802          * OutputPage::showPermissionsErrorPage().
2803          */
2804         public function doRollback(
2805                 $fromP, $summary, $token, $bot, &$resultDetails, User $user, $tags = null
2806         ) {
2807                 $resultDetails = null;
2808
2809                 // Check permissions
2810                 $editErrors = $this->mTitle->getUserPermissionsErrors( 'edit', $user );
2811                 $rollbackErrors = $this->mTitle->getUserPermissionsErrors( 'rollback', $user );
2812                 $errors = array_merge( $editErrors, wfArrayDiff2( $rollbackErrors, $editErrors ) );
2813
2814                 if ( !$user->matchEditToken( $token, 'rollback' ) ) {
2815                         $errors[] = [ 'sessionfailure' ];
2816                 }
2817
2818                 if ( $user->pingLimiter( 'rollback' ) || $user->pingLimiter() ) {
2819                         $errors[] = [ 'actionthrottledtext' ];
2820                 }
2821
2822                 // If there were errors, bail out now
2823                 if ( !empty( $errors ) ) {
2824                         return $errors;
2825                 }
2826
2827                 return $this->commitRollback( $fromP, $summary, $bot, $resultDetails, $user, $tags );
2828         }
2829
2830         /**
2831          * Backend implementation of doRollback(), please refer there for parameter
2832          * and return value documentation
2833          *
2834          * NOTE: This function does NOT check ANY permissions, it just commits the
2835          * rollback to the DB. Therefore, you should only call this function direct-
2836          * ly if you want to use custom permissions checks. If you don't, use
2837          * doRollback() instead.
2838          * @param string $fromP Name of the user whose edits to rollback.
2839          * @param string $summary Custom summary. Set to default summary if empty.
2840          * @param bool $bot If true, mark all reverted edits as bot.
2841          *
2842          * @param array &$resultDetails Contains result-specific array of additional values
2843          * @param User $guser The user performing the rollback
2844          * @param array|null $tags Change tags to apply to the rollback
2845          * Callers are responsible for permission checks
2846          * (with ChangeTags::canAddTagsAccompanyingChange)
2847          *
2848          * @return array An array of error messages, as returned by Status::getErrorsArray()
2849          */
2850         public function commitRollback( $fromP, $summary, $bot,
2851                 &$resultDetails, User $guser, $tags = null
2852         ) {
2853                 global $wgUseRCPatrol;
2854
2855                 $dbw = wfGetDB( DB_MASTER );
2856
2857                 if ( wfReadOnly() ) {
2858                         return [ [ 'readonlytext' ] ];
2859                 }
2860
2861                 // Begin revision creation cycle by creating a PageUpdater.
2862                 // If the page is changed concurrently after grabParentRevision(), the rollback will fail.
2863                 $updater = $this->newPageUpdater( $guser );
2864                 $current = $updater->grabParentRevision();
2865
2866                 if ( is_null( $current ) ) {
2867                         // Something wrong... no page?
2868                         return [ [ 'notanarticle' ] ];
2869                 }
2870
2871                 $currentEditorForPublic = $current->getUser( RevisionRecord::FOR_PUBLIC );
2872                 $legacyCurrent = new Revision( $current );
2873                 $from = str_replace( '_', ' ', $fromP );
2874
2875                 // User name given should match up with the top revision.
2876                 // If the revision's user is not visible, then $from should be empty.
2877                 if ( $from !== ( $currentEditorForPublic ? $currentEditorForPublic->getName() : '' ) ) {
2878                         $resultDetails = [ 'current' => $legacyCurrent ];
2879                         return [ [ 'alreadyrolled',
2880                                 htmlspecialchars( $this->mTitle->getPrefixedText() ),
2881                                 htmlspecialchars( $fromP ),
2882                                 htmlspecialchars( $currentEditorForPublic ? $currentEditorForPublic->getName() : '' )
2883                         ] ];
2884                 }
2885
2886                 // Get the last edit not by this person...
2887                 // Note: these may not be public values
2888                 $actorWhere = ActorMigration::newMigration()->getWhere(
2889                         $dbw,
2890                         'rev_user',
2891                         $current->getUser( RevisionRecord::RAW )
2892                 );
2893
2894                 $s = $dbw->selectRow(
2895                         [ 'revision' ] + $actorWhere['tables'],
2896                         [ 'rev_id', 'rev_timestamp', 'rev_deleted' ],
2897                         [
2898                                 'rev_page' => $current->getPageId(),
2899                                 'NOT(' . $actorWhere['conds'] . ')',
2900                         ],
2901                         __METHOD__,
2902                         [
2903                                 'USE INDEX' => [ 'revision' => 'page_timestamp' ],
2904                                 'ORDER BY' => 'rev_timestamp DESC'
2905                         ],
2906                         $actorWhere['joins']
2907                 );
2908                 if ( $s === false ) {
2909                         // No one else ever edited this page
2910                         return [ [ 'cantrollback' ] ];
2911                 } elseif ( $s->rev_deleted & RevisionRecord::DELETED_TEXT
2912                         || $s->rev_deleted & RevisionRecord::DELETED_USER
2913                 ) {
2914                         // Only admins can see this text
2915                         return [ [ 'notvisiblerev' ] ];
2916                 }
2917
2918                 // Generate the edit summary if necessary
2919                 $target = $this->getRevisionStore()->getRevisionById(
2920                         $s->rev_id,
2921                         RevisionStore::READ_LATEST
2922                 );
2923                 if ( empty( $summary ) ) {
2924                         if ( !$currentEditorForPublic ) { // no public user name
2925                                 $summary = wfMessage( 'revertpage-nouser' );
2926                         } else {
2927                                 $summary = wfMessage( 'revertpage' );
2928                         }
2929                 }
2930                 $legacyTarget = new Revision( $target );
2931                 $targetEditorForPublic = $target->getUser( RevisionRecord::FOR_PUBLIC );
2932
2933                 // Allow the custom summary to use the same args as the default message
2934                 $contLang = MediaWikiServices::getInstance()->getContentLanguage();
2935                 $args = [
2936                         $targetEditorForPublic ? $targetEditorForPublic->getName() : null,
2937                         $currentEditorForPublic ? $currentEditorForPublic->getName() : null,
2938                         $s->rev_id,
2939                         $contLang->timeanddate( wfTimestamp( TS_MW, $s->rev_timestamp ) ),
2940                         $current->getId(),
2941                         $contLang->timeanddate( $current->getTimestamp() )
2942                 ];
2943                 if ( $summary instanceof Message ) {
2944                         $summary = $summary->params( $args )->inContentLanguage()->text();
2945                 } else {
2946                         $summary = wfMsgReplaceArgs( $summary, $args );
2947                 }
2948
2949                 // Trim spaces on user supplied text
2950                 $summary = trim( $summary );
2951
2952                 // Save
2953                 $flags = EDIT_UPDATE | EDIT_INTERNAL;
2954
2955                 if ( $guser->isAllowed( 'minoredit' ) ) {
2956                         $flags |= EDIT_MINOR;
2957                 }
2958
2959                 if ( $bot && ( $guser->isAllowedAny( 'markbotedits', 'bot' ) ) ) {
2960                         $flags |= EDIT_FORCE_BOT;
2961                 }
2962
2963                 // TODO: MCR: also log model changes in other slots, in case that becomes possible!
2964                 $currentContent = $current->getContent( 'main' );
2965                 $targetContent = $target->getContent( 'main' );
2966                 $changingContentModel = $targetContent->getModel() !== $currentContent->getModel();
2967
2968                 if ( in_array( 'mw-rollback', ChangeTags::getSoftwareTags() ) ) {
2969                         $tags[] = 'mw-rollback';
2970                 }
2971
2972                 // Build rollback revision:
2973                 // Restore old content
2974                 // TODO: MCR: test this once we can store multiple slots
2975                 foreach ( $target->getSlots()->getSlots() as $slot ) {
2976                         $updater->inheritSlot( $slot );
2977                 }
2978
2979                 // Remove extra slots
2980                 // TODO: MCR: test this once we can store multiple slots
2981                 foreach ( $current->getSlotRoles() as $role ) {
2982                         if ( !$target->hasSlot( $role ) ) {
2983                                 $updater->removeSlot( $role );
2984                         }
2985                 }
2986
2987                 $updater->setOriginalRevisionId( $target->getId() );
2988                 // Do not call setUndidRevisionId(), that causes an extra "mw-undo" tag to be added (T190374)
2989                 $updater->addTags( $tags );
2990
2991                 // TODO: this logic should not be in the storage layer, it's here for compatibility
2992                 // with 1.31 behavior. Applying the 'autopatrol' right should be done in the same
2993                 // place the 'bot' right is handled, which is currently in EditPage::attemptSave.
2994                 if ( $wgUseRCPatrol && $this->getTitle()->userCan( 'autopatrol', $guser ) ) {
2995                         $updater->setRcPatrolStatus( RecentChange::PRC_AUTOPATROLLED );
2996                 }
2997
2998                 // Actually store the rollback
2999                 $rev = $updater->saveRevision(
3000                         CommentStoreComment::newUnsavedComment( $summary ),
3001                         $flags
3002                 );
3003
3004                 // Set patrolling and bot flag on the edits, which gets rollbacked.
3005                 // This is done even on edit failure to have patrolling in that case (T64157).
3006                 $set = [];
3007                 if ( $bot && $guser->isAllowed( 'markbotedits' ) ) {
3008                         // Mark all reverted edits as bot
3009                         $set['rc_bot'] = 1;
3010                 }
3011
3012                 if ( $wgUseRCPatrol ) {
3013                         // Mark all reverted edits as patrolled
3014                         $set['rc_patrolled'] = RecentChange::PRC_PATROLLED;
3015                 }
3016
3017                 if ( count( $set ) ) {
3018                         $actorWhere = ActorMigration::newMigration()->getWhere(
3019                                 $dbw,
3020                                 'rc_user',
3021                                 $current->getUser( RevisionRecord::RAW ),
3022                                 false
3023                         );
3024                         $dbw->update( 'recentchanges', $set,
3025                                 [ /* WHERE */
3026                                         'rc_cur_id' => $current->getPageId(),
3027                                         'rc_timestamp > ' . $dbw->addQuotes( $s->rev_timestamp ),
3028                                         $actorWhere['conds'], // No tables/joins are needed for rc_user
3029                                 ],
3030                                 __METHOD__
3031                         );
3032                 }
3033
3034                 if ( !$updater->wasSuccessful() ) {
3035                         return $updater->getStatus()->getErrorsArray();
3036                 }
3037
3038                 // Report if the edit was not created because it did not change the content.
3039                 if ( $updater->isUnchanged() ) {
3040                         $resultDetails = [ 'current' => $legacyCurrent ];
3041                         return [ [ 'alreadyrolled',
3042                                         htmlspecialchars( $this->mTitle->getPrefixedText() ),
3043                                         htmlspecialchars( $fromP ),
3044                                         htmlspecialchars( $targetEditorForPublic ? $targetEditorForPublic->getName() : '' )
3045                         ] ];
3046                 }
3047
3048                 if ( $changingContentModel ) {
3049                         // If the content model changed during the rollback,
3050                         // make sure it gets logged to Special:Log/contentmodel
3051                         $log = new ManualLogEntry( 'contentmodel', 'change' );
3052                         $log->setPerformer( $guser );
3053                         $log->setTarget( $this->mTitle );
3054                         $log->setComment( $summary );
3055                         $log->setParameters( [
3056                                 '4::oldmodel' => $currentContent->getModel(),
3057                                 '5::newmodel' => $targetContent->getModel(),
3058                         ] );
3059
3060                         $logId = $log->insert( $dbw );
3061                         $log->publish( $logId );
3062                 }
3063
3064                 $revId = $rev->getId();
3065
3066                 Hooks::run( 'ArticleRollbackComplete', [ $this, $guser, $legacyTarget, $legacyCurrent ] );
3067
3068                 $resultDetails = [
3069                         'summary' => $summary,
3070                         'current' => $legacyCurrent,
3071                         'target' => $legacyTarget,
3072                         'newid' => $revId,
3073                         'tags' => $tags
3074                 ];
3075
3076                 // TODO: make this return a Status object and wrap $resultDetails in that.
3077                 return [];
3078         }
3079
3080         /**
3081          * The onArticle*() functions are supposed to be a kind of hooks
3082          * which should be called whenever any of the specified actions
3083          * are done.
3084          *
3085          * This is a good place to put code to clear caches, for instance.
3086          *
3087          * This is called on page move and undelete, as well as edit
3088          *
3089          * @param Title $title
3090          */
3091         public static function onArticleCreate( Title $title ) {
3092                 // TODO: move this into a PageEventEmitter service
3093
3094                 // Update existence markers on article/talk tabs...
3095                 $other = $title->getOtherPage();
3096
3097                 $other->purgeSquid();
3098
3099                 $title->touchLinks();
3100                 $title->purgeSquid();
3101                 $title->deleteTitleProtection();
3102
3103                 MediaWikiServices::getInstance()->getLinkCache()->invalidateTitle( $title );
3104
3105                 // Invalidate caches of articles which include this page
3106                 DeferredUpdates::addUpdate(
3107                         new HTMLCacheUpdate( $title, 'templatelinks', 'page-create' )
3108                 );
3109
3110                 if ( $title->getNamespace() == NS_CATEGORY ) {
3111                         // Load the Category object, which will schedule a job to create
3112                         // the category table row if necessary. Checking a replica DB is ok
3113                         // here, in the worst case it'll run an unnecessary recount job on
3114                         // a category that probably doesn't have many members.
3115                         Category::newFromTitle( $title )->getID();
3116                 }
3117         }
3118
3119         /**
3120          * Clears caches when article is deleted
3121          *
3122          * @param Title $title
3123          */
3124         public static function onArticleDelete( Title $title ) {
3125                 // TODO: move this into a PageEventEmitter service
3126
3127                 // Update existence markers on article/talk tabs...
3128                 // Clear Backlink cache first so that purge jobs use more up-to-date backlink information
3129                 BacklinkCache::get( $title )->clear();
3130                 $other = $title->getOtherPage();
3131
3132                 $other->purgeSquid();
3133
3134                 $title->touchLinks();
3135                 $title->purgeSquid();
3136
3137                 MediaWikiServices::getInstance()->getLinkCache()->invalidateTitle( $title );
3138
3139                 // File cache
3140                 HTMLFileCache::clearFileCache( $title );
3141                 InfoAction::invalidateCache( $title );
3142
3143                 // Messages
3144                 if ( $title->getNamespace() == NS_MEDIAWIKI ) {
3145                         MessageCache::singleton()->updateMessageOverride( $title, null );
3146                 }
3147
3148                 // Images
3149                 if ( $title->getNamespace() == NS_FILE ) {
3150                         DeferredUpdates::addUpdate(
3151                                 new HTMLCacheUpdate( $title, 'imagelinks', 'page-delete' )
3152                         );
3153                 }
3154
3155                 // User talk pages
3156                 if ( $title->getNamespace() == NS_USER_TALK ) {
3157                         $user = User::newFromName( $title->getText(), false );
3158                         if ( $user ) {
3159                                 $user->setNewtalk( false );
3160                         }
3161                 }
3162
3163                 // Image redirects
3164                 RepoGroup::singleton()->getLocalRepo()->invalidateImageRedirect( $title );
3165
3166                 // Purge cross-wiki cache entities referencing this page
3167                 self::purgeInterwikiCheckKey( $title );
3168         }
3169
3170         /**
3171          * Purge caches on page update etc
3172          *
3173          * @param Title $title
3174          * @param Revision|null $revision Revision that was just saved, may be null
3175          * @param string[]|null $slotsChanged The role names of the slots that were changed.
3176          *        If not given, all slots are assumed to have changed.
3177          */
3178         public static function onArticleEdit(
3179                 Title $title,
3180                 Revision $revision = null,
3181                 $slotsChanged = null
3182         ) {
3183                 // TODO: move this into a PageEventEmitter service
3184
3185                 if ( $slotsChanged === null || in_array( 'main',  $slotsChanged ) ) {
3186                         // Invalidate caches of articles which include this page.
3187                         // Only for the main slot, because only the main slot is transcluded.
3188                         // TODO: MCR: not true for TemplateStyles! [SlotHandler]
3189                         DeferredUpdates::addUpdate(
3190                                 new HTMLCacheUpdate( $title, 'templatelinks', 'page-edit' )
3191                         );
3192                 }
3193
3194                 // Invalidate the caches of all pages which redirect here
3195                 DeferredUpdates::addUpdate(
3196                         new HTMLCacheUpdate( $title, 'redirect', 'page-edit' )
3197                 );
3198
3199                 MediaWikiServices::getInstance()->getLinkCache()->invalidateTitle( $title );
3200
3201                 // Purge CDN for this page only
3202                 $title->purgeSquid();
3203                 // Clear file cache for this page only
3204                 HTMLFileCache::clearFileCache( $title );
3205
3206                 // Purge ?action=info cache
3207                 $revid = $revision ? $revision->getId() : null;
3208                 DeferredUpdates::addCallableUpdate( function () use ( $title, $revid ) {
3209                         InfoAction::invalidateCache( $title, $revid );
3210                 } );
3211
3212                 // Purge cross-wiki cache entities referencing this page
3213                 self::purgeInterwikiCheckKey( $title );
3214         }
3215
3216         /**#@-*/
3217
3218         /**
3219          * Purge the check key for cross-wiki cache entries referencing this page
3220          *
3221          * @param Title $title
3222          */
3223         private static function purgeInterwikiCheckKey( Title $title ) {
3224                 global $wgEnableScaryTranscluding;
3225
3226                 if ( !$wgEnableScaryTranscluding ) {
3227                         return; // @todo: perhaps this wiki is only used as a *source* for content?
3228                 }
3229
3230                 DeferredUpdates::addCallableUpdate( function () use ( $title ) {
3231                         $cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
3232                         $cache->resetCheckKey(
3233                                 // Do not include the namespace since there can be multiple aliases to it
3234                                 // due to different namespace text definitions on different wikis. This only
3235                                 // means that some cache invalidations happen that are not strictly needed.
3236                                 $cache->makeGlobalKey( 'interwiki-page', wfWikiID(), $title->getDBkey() )
3237                         );
3238                 } );
3239         }
3240
3241         /**
3242          * Returns a list of categories this page is a member of.
3243          * Results will include hidden categories
3244          *
3245          * @return TitleArray
3246          */
3247         public function getCategories() {
3248                 $id = $this->getId();
3249                 if ( $id == 0 ) {
3250                         return TitleArray::newFromResult( new FakeResultWrapper( [] ) );
3251                 }
3252
3253                 $dbr = wfGetDB( DB_REPLICA );
3254                 $res = $dbr->select( 'categorylinks',
3255                         [ 'cl_to AS page_title, ' . NS_CATEGORY . ' AS page_namespace' ],
3256                         // Have to do that since Database::fieldNamesWithAlias treats numeric indexes
3257                         // as not being aliases, and NS_CATEGORY is numeric
3258                         [ 'cl_from' => $id ],
3259                         __METHOD__ );
3260
3261                 return TitleArray::newFromResult( $res );
3262         }
3263
3264         /**
3265          * Returns a list of hidden categories this page is a member of.
3266          * Uses the page_props and categorylinks tables.
3267          *
3268          * @return array Array of Title objects
3269          */
3270         public function getHiddenCategories() {
3271                 $result = [];
3272                 $id = $this->getId();
3273
3274                 if ( $id == 0 ) {
3275                         return [];
3276                 }
3277
3278                 $dbr = wfGetDB( DB_REPLICA );
3279                 $res = $dbr->select( [ 'categorylinks', 'page_props', 'page' ],
3280                         [ 'cl_to' ],
3281                         [ 'cl_from' => $id, 'pp_page=page_id', 'pp_propname' => 'hiddencat',
3282                                 'page_namespace' => NS_CATEGORY, 'page_title=cl_to' ],
3283                         __METHOD__ );
3284
3285                 if ( $res !== false ) {
3286                         foreach ( $res as $row ) {
3287                                 $result[] = Title::makeTitle( NS_CATEGORY, $row->cl_to );
3288                         }
3289                 }
3290
3291                 return $result;
3292         }
3293
3294         /**
3295          * Auto-generates a deletion reason
3296          *
3297          * @param bool &$hasHistory Whether the page has a history
3298          * @return string|bool String containing deletion reason or empty string, or boolean false
3299          *    if no revision occurred
3300          */
3301         public function getAutoDeleteReason( &$hasHistory ) {
3302                 return $this->getContentHandler()->getAutoDeleteReason( $this->getTitle(), $hasHistory );
3303         }
3304
3305         /**
3306          * Update all the appropriate counts in the category table, given that
3307          * we've added the categories $added and deleted the categories $deleted.
3308          *
3309          * This should only be called from deferred updates or jobs to avoid contention.
3310          *
3311          * @param array $added The names of categories that were added
3312          * @param array $deleted The names of categories that were deleted
3313          * @param int $id Page ID (this should be the original deleted page ID)
3314          */
3315         public function updateCategoryCounts( array $added, array $deleted, $id = 0 ) {
3316                 $id = $id ?: $this->getId();
3317                 $type = MWNamespace::getCategoryLinkType( $this->getTitle()->getNamespace() );
3318
3319                 $addFields = [ 'cat_pages = cat_pages + 1' ];
3320                 $removeFields = [ 'cat_pages = cat_pages - 1' ];
3321                 if ( $type !== 'page' ) {
3322                         $addFields[] = "cat_{$type}s = cat_{$type}s + 1";
3323                         $removeFields[] = "cat_{$type}s = cat_{$type}s - 1";
3324                 }
3325
3326                 $dbw = wfGetDB( DB_MASTER );
3327
3328                 if ( count( $added ) ) {
3329                         $existingAdded = $dbw->selectFieldValues(
3330                                 'category',
3331                                 'cat_title',
3332                                 [ 'cat_title' => $added ],
3333                                 __METHOD__
3334                         );
3335
3336                         // For category rows that already exist, do a plain
3337                         // UPDATE instead of INSERT...ON DUPLICATE KEY UPDATE
3338                         // to avoid creating gaps in the cat_id sequence.
3339                         if ( count( $existingAdded ) ) {
3340                                 $dbw->update(
3341                                         'category',
3342                                         $addFields,
3343                                         [ 'cat_title' => $existingAdded ],
3344                                         __METHOD__
3345                                 );
3346                         }
3347
3348                         $missingAdded = array_diff( $added, $existingAdded );
3349                         if ( count( $missingAdded ) ) {
3350                                 $insertRows = [];
3351                                 foreach ( $missingAdded as $cat ) {
3352                                         $insertRows[] = [
3353                                                 'cat_title'   => $cat,
3354                                                 'cat_pages'   => 1,
3355                                                 'cat_subcats' => ( $type === 'subcat' ) ? 1 : 0,
3356                                                 'cat_files'   => ( $type === 'file' ) ? 1 : 0,
3357                                         ];
3358                                 }
3359                                 $dbw->upsert(
3360                                         'category',
3361                                         $insertRows,
3362                                         [ 'cat_title' ],
3363                                         $addFields,
3364                                         __METHOD__
3365                                 );
3366                         }
3367                 }
3368
3369                 if ( count( $deleted ) ) {
3370                         $dbw->update(
3371                                 'category',
3372                                 $removeFields,
3373                                 [ 'cat_title' => $deleted ],
3374                                 __METHOD__
3375                         );
3376                 }
3377
3378                 foreach ( $added as $catName ) {
3379                         $cat = Category::newFromName( $catName );
3380                         Hooks::run( 'CategoryAfterPageAdded', [ $cat, $this ] );
3381                 }
3382
3383                 foreach ( $deleted as $catName ) {
3384                         $cat = Category::newFromName( $catName );
3385                         Hooks::run( 'CategoryAfterPageRemoved', [ $cat, $this, $id ] );
3386                         // Refresh counts on categories that should be empty now (after commit, T166757)
3387                         DeferredUpdates::addCallableUpdate( function () use ( $cat ) {
3388                                 $cat->refreshCountsIfEmpty();
3389                         } );
3390                 }
3391         }
3392
3393         /**
3394          * Opportunistically enqueue link update jobs given fresh parser output if useful
3395          *
3396          * @param ParserOutput $parserOutput Current version page output
3397          * @since 1.25
3398          */
3399         public function triggerOpportunisticLinksUpdate( ParserOutput $parserOutput ) {
3400                 if ( wfReadOnly() ) {
3401                         return;
3402                 }
3403
3404                 if ( !Hooks::run( 'OpportunisticLinksUpdate',
3405                         [ $this, $this->mTitle, $parserOutput ]
3406                 ) ) {
3407                         return;
3408                 }
3409
3410                 $config = RequestContext::getMain()->getConfig();
3411
3412                 $params = [
3413                         'isOpportunistic' => true,
3414                         'rootJobTimestamp' => $parserOutput->getCacheTime()
3415                 ];
3416
3417                 if ( $this->mTitle->areRestrictionsCascading() ) {
3418                         // If the page is cascade protecting, the links should really be up-to-date
3419                         JobQueueGroup::singleton()->lazyPush(
3420                                 RefreshLinksJob::newPrioritized( $this->mTitle, $params )
3421                         );
3422                 } elseif ( !$config->get( 'MiserMode' ) && $parserOutput->hasDynamicContent() ) {
3423                         // Assume the output contains "dynamic" time/random based magic words.
3424                         // Only update pages that expired due to dynamic content and NOT due to edits
3425                         // to referenced templates/files. When the cache expires due to dynamic content,
3426                         // page_touched is unchanged. We want to avoid triggering redundant jobs due to
3427                         // views of pages that were just purged via HTMLCacheUpdateJob. In that case, the
3428                         // template/file edit already triggered recursive RefreshLinksJob jobs.
3429                         if ( $this->getLinksTimestamp() > $this->getTouched() ) {
3430                                 // If a page is uncacheable, do not keep spamming a job for it.
3431                                 // Although it would be de-duplicated, it would still waste I/O.
3432                                 $cache = ObjectCache::getLocalClusterInstance();
3433                                 $key = $cache->makeKey( 'dynamic-linksupdate', 'last', $this->getId() );
3434                                 $ttl = max( $parserOutput->getCacheExpiry(), 3600 );
3435                                 if ( $cache->add( $key, time(), $ttl ) ) {
3436                                         JobQueueGroup::singleton()->lazyPush(
3437                                                 RefreshLinksJob::newDynamic( $this->mTitle, $params )
3438                                         );
3439                                 }
3440                         }
3441                 }
3442         }
3443
3444         /**
3445          * Returns a list of updates to be performed when this page is deleted. The
3446          * updates should remove any information about this page from secondary data
3447          * stores such as links tables.
3448          *
3449          * @param Content|null $content Optional Content object for determining the
3450          *   necessary updates.
3451          * @return DeferrableUpdate[]
3452          */
3453         public function getDeletionUpdates( Content $content = null ) {
3454                 if ( !$content ) {
3455                         // load content object, which may be used to determine the necessary updates.
3456                         // XXX: the content may not be needed to determine the updates.
3457                         try {
3458                                 $content = $this->getContent( Revision::RAW );
3459                         } catch ( Exception $ex ) {
3460                                 // If we can't load the content, something is wrong. Perhaps that's why
3461                                 // the user is trying to delete the page, so let's not fail in that case.
3462                                 // Note that doDeleteArticleReal() will already have logged an issue with
3463                                 // loading the content.
3464                         }
3465                 }
3466
3467                 if ( !$content ) {
3468                         $updates = [];
3469                 } else {
3470                         $updates = $content->getDeletionUpdates( $this );
3471                 }
3472
3473                 Hooks::run( 'WikiPageDeletionUpdates', [ $this, $content, &$updates ] );
3474                 return $updates;
3475         }
3476
3477         /**
3478          * Whether this content displayed on this page
3479          * comes from the local database
3480          *
3481          * @since 1.28
3482          * @return bool
3483          */
3484         public function isLocal() {
3485                 return true;
3486         }
3487
3488         /**
3489          * The display name for the site this content
3490          * come from. If a subclass overrides isLocal(),
3491          * this could return something other than the
3492          * current site name
3493          *
3494          * @since 1.28
3495          * @return string
3496          */
3497         public function getWikiDisplayName() {
3498                 global $wgSitename;
3499                 return $wgSitename;
3500         }
3501
3502         /**
3503          * Get the source URL for the content on this page,
3504          * typically the canonical URL, but may be a remote
3505          * link if the content comes from another site
3506          *
3507          * @since 1.28
3508          * @return string
3509          */
3510         public function getSourceURL() {
3511                 return $this->getTitle()->getCanonicalURL();
3512         }
3513
3514         /**
3515          * @param WANObjectCache $cache
3516          * @return string[]
3517          * @since 1.28
3518          */
3519         public function getMutableCacheKeys( WANObjectCache $cache ) {
3520                 $linkCache = MediaWikiServices::getInstance()->getLinkCache();
3521
3522                 return $linkCache->getMutableCacheKeys( $cache, $this->getTitle() );
3523         }
3524
3525 }