includes/deferred/LinksUpdate.php

   1 <?php
   2 /**
   3  * Updater for link tracking tables after a page edit.
   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 /**
  24  * See docs/deferred.txt
  25  *
  26  * @todo document (e.g. one-sentence top-level class description).
  27  */
  28 class LinksUpdate extends SqlDataUpdate {
  29         // @todo make members protected, but make sure extensions don't break
  30
  31         /** @var int Page ID of the article linked from */
  32         public $mId;
  33
  34         /** @var Title object of the article linked from */
  35         public $mTitle;
  36
  37         /** @var ParserOutput */
  38         public $mParserOutput;
  39
  40         /** @var array Map of title strings to IDs for the links in the document */
  41         public $mLinks;
  42
  43         /** @var array DB keys of the images used, in the array key only */
  44         public $mImages;
  45
  46         /** @var array Map of title strings to IDs for the template references, including broken ones */
  47         public $mTemplates;
  48
  49         /** @var array URLs of external links, array key only */
  50         public $mExternals;
  51
  52         /** @var array Map of category names to sort keys */
  53         public $mCategories;
  54
  55         /** @var array ap of language codes to titles */
  56         public $mInterlangs;
  57
  58         /** @var array Map of arbitrary name to value */
  59         public $mProperties;
  60
  61         /** @var DatabaseBase Database connection reference */
  62         public $mDb;
  63
  64         /** @var array SELECT options to be used */
  65         public $mOptions;
  66
  67         /** @var bool Whether to queue jobs for recursive updates */
  68         public $mRecursive;
  69
  70         /**
  71          * @var null|array Added links if calculated.
  72          */
  73         private $linkInsertions = null;
  74
  75         /**
  76          * @var null|array Deleted links if calculated.
  77          */
  78         private $linkDeletions = null;
  79
  80         /**
  81          * Constructor
  82          *
  83          * @param Title $title Title of the page we're updating
  84          * @param ParserOutput $parserOutput Output from a full parse of this page
  85          * @param bool $recursive Queue jobs for recursive updates?
  86          * @throws MWException
  87          */
  88         function __construct( $title, $parserOutput, $recursive = true ) {
  89                 parent::__construct( false ); // no implicit transaction
  90
  91                 if ( !( $title instanceof Title ) ) {
  92                         throw new MWException( "The calling convention to LinksUpdate::LinksUpdate() has changed. " .
  93                                 "Please see Article::editUpdates() for an invocation example.\n" );
  94                 }
  95
  96                 if ( !( $parserOutput instanceof ParserOutput ) ) {
  97                         throw new MWException( "The calling convention to LinksUpdate::__construct() has changed. " .
  98                                 "Please see WikiPage::doEditUpdates() for an invocation example.\n" );
  99                 }
 100
 101                 $this->mTitle = $title;
 102                 $this->mId = $title->getArticleID();
 103
 104                 if ( !$this->mId ) {
 105                         throw new MWException( "The Title object did not provide an article " .
 106                                 "ID. Perhaps the page doesn't exist?" );
 107                 }
 108
 109                 $this->mParserOutput = $parserOutput;
 110
 111                 $this->mLinks = $parserOutput->getLinks();
 112                 $this->mImages = $parserOutput->getImages();
 113                 $this->mTemplates = $parserOutput->getTemplates();
 114                 $this->mExternals = $parserOutput->getExternalLinks();
 115                 $this->mCategories = $parserOutput->getCategories();
 116                 $this->mProperties = $parserOutput->getProperties();
 117                 $this->mInterwikis = $parserOutput->getInterwikiLinks();
 118
 119                 # Convert the format of the interlanguage links
 120                 # I didn't want to change it in the ParserOutput, because that array is passed all
 121                 # the way back to the skin, so either a skin API break would be required, or an
 122                 # inefficient back-conversion.
 123                 $ill = $parserOutput->getLanguageLinks();
 124                 $this->mInterlangs = array();
 125                 foreach ( $ill as $link ) {
 126                         list( $key, $title ) = explode( ':', $link, 2 );
 127                         $this->mInterlangs[$key] = $title;
 128                 }
 129
 130                 foreach ( $this->mCategories as &$sortkey ) {
 131                         # If the sortkey is longer then 255 bytes,
 132                         # it truncated by DB, and then doesn't get
 133                         # matched when comparing existing vs current
 134                         # categories, causing bug 25254.
 135                         # Also. substr behaves weird when given "".
 136                         if ( $sortkey !== '' ) {
 137                                 $sortkey = substr( $sortkey, 0, 255 );
 138                         }
 139                 }
 140
 141                 $this->mRecursive = $recursive;
 142
 143                 wfRunHooks( 'LinksUpdateConstructed', array( &$this ) );
 144         }
 145
 146         /**
 147          * Update link tables with outgoing links from an updated article
 148          */
 149         public function doUpdate() {
 150                 wfRunHooks( 'LinksUpdate', array( &$this ) );
 151                 $this->doIncrementalUpdate();
 152                 wfRunHooks( 'LinksUpdateComplete', array( &$this ) );
 153         }
 154
 155         protected function doIncrementalUpdate() {
 156                 wfProfileIn( __METHOD__ );
 157
 158                 # Page links
 159                 $existing = $this->getExistingLinks();
 160                 $this->linkDeletions = $this->getLinkDeletions( $existing );
 161                 $this->linkInsertions = $this->getLinkInsertions( $existing );
 162                 $this->incrTableUpdate( 'pagelinks', 'pl', $this->linkDeletions, $this->linkInsertions );
 163
 164                 # Image links
 165                 $existing = $this->getExistingImages();
 166
 167                 $imageDeletes = $this->getImageDeletions( $existing );
 168                 $this->incrTableUpdate( 'imagelinks', 'il', $imageDeletes,
 169                         $this->getImageInsertions( $existing ) );
 170
 171                 # Invalidate all image description pages which had links added or removed
 172                 $imageUpdates = $imageDeletes + array_diff_key( $this->mImages, $existing );
 173                 $this->invalidateImageDescriptions( $imageUpdates );
 174
 175                 # External links
 176                 $existing = $this->getExistingExternals();
 177                 $this->incrTableUpdate( 'externallinks', 'el', $this->getExternalDeletions( $existing ),
 178                         $this->getExternalInsertions( $existing ) );
 179
 180                 # Language links
 181                 $existing = $this->getExistingInterlangs();
 182                 $this->incrTableUpdate( 'langlinks', 'll', $this->getInterlangDeletions( $existing ),
 183                         $this->getInterlangInsertions( $existing ) );
 184
 185                 # Inline interwiki links
 186                 $existing = $this->getExistingInterwikis();
 187                 $this->incrTableUpdate( 'iwlinks', 'iwl', $this->getInterwikiDeletions( $existing ),
 188                         $this->getInterwikiInsertions( $existing ) );
 189
 190                 # Template links
 191                 $existing = $this->getExistingTemplates();
 192                 $this->incrTableUpdate( 'templatelinks', 'tl', $this->getTemplateDeletions( $existing ),
 193                         $this->getTemplateInsertions( $existing ) );
 194
 195                 # Category links
 196                 $existing = $this->getExistingCategories();
 197
 198                 $categoryDeletes = $this->getCategoryDeletions( $existing );
 199
 200                 $this->incrTableUpdate( 'categorylinks', 'cl', $categoryDeletes,
 201                         $this->getCategoryInsertions( $existing ) );
 202
 203                 # Invalidate all categories which were added, deleted or changed (set symmetric difference)
 204                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 205                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 206                 $this->invalidateCategories( $categoryUpdates );
 207                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 208
 209                 # Page properties
 210                 $existing = $this->getExistingProperties();
 211
 212                 $propertiesDeletes = $this->getPropertyDeletions( $existing );
 213
 214                 $this->incrTableUpdate( 'page_props', 'pp', $propertiesDeletes,
 215                         $this->getPropertyInsertions( $existing ) );
 216
 217                 # Invalidate the necessary pages
 218                 $changed = $propertiesDeletes + array_diff_assoc( $this->mProperties, $existing );
 219                 $this->invalidateProperties( $changed );
 220
 221                 # Update the links table freshness for this title
 222                 $this->updateLinksTimestamp();
 223
 224                 # Refresh links of all pages including this page
 225                 # This will be in a separate transaction
 226                 if ( $this->mRecursive ) {
 227                         $this->queueRecursiveJobs();
 228                 }
 229
 230                 wfProfileOut( __METHOD__ );
 231         }
 232
 233         /**
 234          * Queue recursive jobs for this page
 235          *
 236          * Which means do LinksUpdate on all templates
 237          * that include the current page, using the job queue.
 238          */
 239         function queueRecursiveJobs() {
 240                 self::queueRecursiveJobsForTable( $this->mTitle, 'templatelinks' );
 241         }
 242
 243         /**
 244          * Queue a RefreshLinks job for any table.
 245          *
 246          * @param Title $title Title to do job for
 247          * @param string $table Table to use (e.g. 'templatelinks')
 248          */
 249         public static function queueRecursiveJobsForTable( Title $title, $table ) {
 250                 wfProfileIn( __METHOD__ );
 251                 if ( $title->getBacklinkCache()->hasLinks( $table ) ) {
 252                         $job = new RefreshLinksJob(
 253                                 $title,
 254                                 array(
 255                                         'table'     => $table,
 256                                         'recursive' => true,
 257                                 ) + Job::newRootJobParams( // "overall" refresh links job info
 258                                         "refreshlinks:{$table}:{$title->getPrefixedText()}"
 259                                 )
 260                         );
 261                         JobQueueGroup::singleton()->push( $job );
 262                         JobQueueGroup::singleton()->deduplicateRootJob( $job );
 263                 }
 264                 wfProfileOut( __METHOD__ );
 265         }
 266
 267         /**
 268          * @param $cats
 269          */
 270         function invalidateCategories( $cats ) {
 271                 $this->invalidatePages( NS_CATEGORY, array_keys( $cats ) );
 272         }
 273
 274         /**
 275          * Update all the appropriate counts in the category table.
 276          * @param array $added Associative array of category name => sort key
 277          * @param array $deleted Associative array of category name => sort key
 278          */
 279         function updateCategoryCounts( $added, $deleted ) {
 280                 $a = WikiPage::factory( $this->mTitle );
 281                 $a->updateCategoryCounts(
 282                         array_keys( $added ), array_keys( $deleted )
 283                 );
 284         }
 285
 286         /**
 287          * @param $images
 288          */
 289         function invalidateImageDescriptions( $images ) {
 290                 $this->invalidatePages( NS_FILE, array_keys( $images ) );
 291         }
 292
 293         /**
 294          * Update a table by doing a delete query then an insert query
 295          * @param string $table Table name
 296          * @param string $prefix Field name prefix
 297          * @param array $deletions
 298          * @param array $insertions Rows to insert
 299          */
 300         function incrTableUpdate( $table, $prefix, $deletions, $insertions ) {
 301                 if ( $table == 'page_props' ) {
 302                         $fromField = 'pp_page';
 303                 } else {
 304                         $fromField = "{$prefix}_from";
 305                 }
 306                 $where = array( $fromField => $this->mId );
 307                 if ( $table == 'pagelinks' || $table == 'templatelinks' || $table == 'iwlinks' ) {
 308                         if ( $table == 'iwlinks' ) {
 309                                 $baseKey = 'iwl_prefix';
 310                         } else {
 311                                 $baseKey = "{$prefix}_namespace";
 312                         }
 313                         $clause = $this->mDb->makeWhereFrom2d( $deletions, $baseKey, "{$prefix}_title" );
 314                         if ( $clause ) {
 315                                 $where[] = $clause;
 316                         } else {
 317                                 $where = false;
 318                         }
 319                 } else {
 320                         if ( $table == 'langlinks' ) {
 321                                 $toField = 'll_lang';
 322                         } elseif ( $table == 'page_props' ) {
 323                                 $toField = 'pp_propname';
 324                         } else {
 325                                 $toField = $prefix . '_to';
 326                         }
 327                         if ( count( $deletions ) ) {
 328                                 $where[] = "$toField IN (" . $this->mDb->makeList( array_keys( $deletions ) ) . ')';
 329                         } else {
 330                                 $where = false;
 331                         }
 332                 }
 333                 if ( $where ) {
 334                         $this->mDb->delete( $table, $where, __METHOD__ );
 335                 }
 336                 if ( count( $insertions ) ) {
 337                         $this->mDb->insert( $table, $insertions, __METHOD__, 'IGNORE' );
 338                         wfRunHooks( 'LinksUpdateAfterInsert', array( $this, $table, $insertions ) );
 339                 }
 340         }
 341
 342         /**
 343          * Get an array of pagelinks insertions for passing to the DB
 344          * Skips the titles specified by the 2-D array $existing
 345          * @param array $existing
 346          * @return array
 347          */
 348         private function getLinkInsertions( $existing = array() ) {
 349                 $arr = array();
 350                 foreach ( $this->mLinks as $ns => $dbkeys ) {
 351                         $diffs = isset( $existing[$ns] )
 352                                 ? array_diff_key( $dbkeys, $existing[$ns] )
 353                                 : $dbkeys;
 354                         foreach ( $diffs as $dbk => $id ) {
 355                                 $arr[] = array(
 356                                         'pl_from' => $this->mId,
 357                                         'pl_namespace' => $ns,
 358                                         'pl_title' => $dbk
 359                                 );
 360                         }
 361                 }
 362
 363                 return $arr;
 364         }
 365
 366         /**
 367          * Get an array of template insertions. Like getLinkInsertions()
 368          * @param array $existing
 369          * @return array
 370          */
 371         private function getTemplateInsertions( $existing = array() ) {
 372                 $arr = array();
 373                 foreach ( $this->mTemplates as $ns => $dbkeys ) {
 374                         $diffs = isset( $existing[$ns] ) ? array_diff_key( $dbkeys, $existing[$ns] ) : $dbkeys;
 375                         foreach ( $diffs as $dbk => $id ) {
 376                                 $arr[] = array(
 377                                         'tl_from' => $this->mId,
 378                                         'tl_namespace' => $ns,
 379                                         'tl_title' => $dbk
 380                                 );
 381                         }
 382                 }
 383
 384                 return $arr;
 385         }
 386
 387         /**
 388          * Get an array of image insertions
 389          * Skips the names specified in $existing
 390          * @param array $existing
 391          * @return array
 392          */
 393         private function getImageInsertions( $existing = array() ) {
 394                 $arr = array();
 395                 $diffs = array_diff_key( $this->mImages, $existing );
 396                 foreach ( $diffs as $iname => $dummy ) {
 397                         $arr[] = array(
 398                                 'il_from' => $this->mId,
 399                                 'il_to' => $iname
 400                         );
 401                 }
 402
 403                 return $arr;
 404         }
 405
 406         /**
 407          * Get an array of externallinks insertions. Skips the names specified in $existing
 408          * @param array $existing
 409          * @return array
 410          */
 411         private function getExternalInsertions( $existing = array() ) {
 412                 $arr = array();
 413                 $diffs = array_diff_key( $this->mExternals, $existing );
 414                 foreach ( $diffs as $url => $dummy ) {
 415                         foreach ( wfMakeUrlIndexes( $url ) as $index ) {
 416                                 $arr[] = array(
 417                                         'el_id' => $this->mDb->nextSequenceValue( 'externallinks_el_id_seq' ),
 418                                         'el_from' => $this->mId,
 419                                         'el_to' => $url,
 420                                         'el_index' => $index,
 421                                 );
 422                         }
 423                 }
 424
 425                 return $arr;
 426         }
 427
 428         /**
 429          * Get an array of category insertions
 430          *
 431          * @param array $existing mapping existing category names to sort keys. If both
 432          * match a link in $this, the link will be omitted from the output
 433          *
 434          * @return array
 435          */
 436         private function getCategoryInsertions( $existing = array() ) {
 437                 global $wgContLang, $wgCategoryCollation;
 438                 $diffs = array_diff_assoc( $this->mCategories, $existing );
 439                 $arr = array();
 440                 foreach ( $diffs as $name => $prefix ) {
 441                         $nt = Title::makeTitleSafe( NS_CATEGORY, $name );
 442                         $wgContLang->findVariantLink( $name, $nt, true );
 443
 444                         if ( $this->mTitle->getNamespace() == NS_CATEGORY ) {
 445                                 $type = 'subcat';
 446                         } elseif ( $this->mTitle->getNamespace() == NS_FILE ) {
 447                                 $type = 'file';
 448                         } else {
 449                                 $type = 'page';
 450                         }
 451
 452                         # Treat custom sortkeys as a prefix, so that if multiple
 453                         # things are forced to sort as '*' or something, they'll
 454                         # sort properly in the category rather than in page_id
 455                         # order or such.
 456                         $sortkey = Collation::singleton()->getSortKey(
 457                                 $this->mTitle->getCategorySortkey( $prefix ) );
 458
 459                         $arr[] = array(
 460                                 'cl_from' => $this->mId,
 461                                 'cl_to' => $name,
 462                                 'cl_sortkey' => $sortkey,
 463                                 'cl_timestamp' => $this->mDb->timestamp(),
 464                                 'cl_sortkey_prefix' => $prefix,
 465                                 'cl_collation' => $wgCategoryCollation,
 466                                 'cl_type' => $type,
 467                         );
 468                 }
 469
 470                 return $arr;
 471         }
 472
 473         /**
 474          * Get an array of interlanguage link insertions
 475          *
 476          * @param array $existing mapping existing language codes to titles
 477          *
 478          * @return array
 479          */
 480         private function getInterlangInsertions( $existing = array() ) {
 481                 $diffs = array_diff_assoc( $this->mInterlangs, $existing );
 482                 $arr = array();
 483                 foreach ( $diffs as $lang => $title ) {
 484                         $arr[] = array(
 485                                 'll_from' => $this->mId,
 486                                 'll_lang' => $lang,
 487                                 'll_title' => $title
 488                         );
 489                 }
 490
 491                 return $arr;
 492         }
 493
 494         /**
 495          * Get an array of page property insertions
 496          * @param array $existing
 497          * @return array
 498          */
 499         function getPropertyInsertions( $existing = array() ) {
 500                 $diffs = array_diff_assoc( $this->mProperties, $existing );
 501                 $arr = array();
 502                 foreach ( $diffs as $name => $value ) {
 503                         $arr[] = array(
 504                                 'pp_page' => $this->mId,
 505                                 'pp_propname' => $name,
 506                                 'pp_value' => $value,
 507                         );
 508                 }
 509
 510                 return $arr;
 511         }
 512
 513         /**
 514          * Get an array of interwiki insertions for passing to the DB
 515          * Skips the titles specified by the 2-D array $existing
 516          * @param array $existing
 517          * @return array
 518          */
 519         private function getInterwikiInsertions( $existing = array() ) {
 520                 $arr = array();
 521                 foreach ( $this->mInterwikis as $prefix => $dbkeys ) {
 522                         $diffs = isset( $existing[$prefix] )
 523                                 ? array_diff_key( $dbkeys, $existing[$prefix] )
 524                                 : $dbkeys;
 525
 526                         foreach ( $diffs as $dbk => $id ) {
 527                                 $arr[] = array(
 528                                         'iwl_from' => $this->mId,
 529                                         'iwl_prefix' => $prefix,
 530                                         'iwl_title' => $dbk
 531                                 );
 532                         }
 533                 }
 534
 535                 return $arr;
 536         }
 537
 538         /**
 539          * Given an array of existing links, returns those links which are not in $this
 540          * and thus should be deleted.
 541          * @param array $existing
 542          * @return array
 543          */
 544         private function getLinkDeletions( $existing ) {
 545                 $del = array();
 546                 foreach ( $existing as $ns => $dbkeys ) {
 547                         if ( isset( $this->mLinks[$ns] ) ) {
 548                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mLinks[$ns] );
 549                         } else {
 550                                 $del[$ns] = $existing[$ns];
 551                         }
 552                 }
 553
 554                 return $del;
 555         }
 556
 557         /**
 558          * Given an array of existing templates, returns those templates which are not in $this
 559          * and thus should be deleted.
 560          * @param array $existing
 561          * @return array
 562          */
 563         private function getTemplateDeletions( $existing ) {
 564                 $del = array();
 565                 foreach ( $existing as $ns => $dbkeys ) {
 566                         if ( isset( $this->mTemplates[$ns] ) ) {
 567                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mTemplates[$ns] );
 568                         } else {
 569                                 $del[$ns] = $existing[$ns];
 570                         }
 571                 }
 572
 573                 return $del;
 574         }
 575
 576         /**
 577          * Given an array of existing images, returns those images which are not in $this
 578          * and thus should be deleted.
 579          * @param array $existing
 580          * @return array
 581          */
 582         private function getImageDeletions( $existing ) {
 583                 return array_diff_key( $existing, $this->mImages );
 584         }
 585
 586         /**
 587          * Given an array of existing external links, returns those links which are not
 588          * in $this and thus should be deleted.
 589          * @param array $existing
 590          * @return array
 591          */
 592         private function getExternalDeletions( $existing ) {
 593                 return array_diff_key( $existing, $this->mExternals );
 594         }
 595
 596         /**
 597          * Given an array of existing categories, returns those categories which are not in $this
 598          * and thus should be deleted.
 599          * @param array $existing
 600          * @return array
 601          */
 602         private function getCategoryDeletions( $existing ) {
 603                 return array_diff_assoc( $existing, $this->mCategories );
 604         }
 605
 606         /**
 607          * Given an array of existing interlanguage links, returns those links which are not
 608          * in $this and thus should be deleted.
 609          * @param array $existing
 610          * @return array
 611          */
 612         private function getInterlangDeletions( $existing ) {
 613                 return array_diff_assoc( $existing, $this->mInterlangs );
 614         }
 615
 616         /**
 617          * Get array of properties which should be deleted.
 618          * @param array $existing
 619          * @return array
 620          */
 621         function getPropertyDeletions( $existing ) {
 622                 return array_diff_assoc( $existing, $this->mProperties );
 623         }
 624
 625         /**
 626          * Given an array of existing interwiki links, returns those links which are not in $this
 627          * and thus should be deleted.
 628          * @param array $existing
 629          * @return array
 630          */
 631         private function getInterwikiDeletions( $existing ) {
 632                 $del = array();
 633                 foreach ( $existing as $prefix => $dbkeys ) {
 634                         if ( isset( $this->mInterwikis[$prefix] ) ) {
 635                                 $del[$prefix] = array_diff_key( $existing[$prefix], $this->mInterwikis[$prefix] );
 636                         } else {
 637                                 $del[$prefix] = $existing[$prefix];
 638                         }
 639                 }
 640
 641                 return $del;
 642         }
 643
 644         /**
 645          * Get an array of existing links, as a 2-D array
 646          *
 647          * @return array
 648          */
 649         private function getExistingLinks() {
 650                 $res = $this->mDb->select( 'pagelinks', array( 'pl_namespace', 'pl_title' ),
 651                         array( 'pl_from' => $this->mId ), __METHOD__, $this->mOptions );
 652                 $arr = array();
 653                 foreach ( $res as $row ) {
 654                         if ( !isset( $arr[$row->pl_namespace] ) ) {
 655                                 $arr[$row->pl_namespace] = array();
 656                         }
 657                         $arr[$row->pl_namespace][$row->pl_title] = 1;
 658                 }
 659
 660                 return $arr;
 661         }
 662
 663         /**
 664          * Get an array of existing templates, as a 2-D array
 665          *
 666          * @return array
 667          */
 668         private function getExistingTemplates() {
 669                 $res = $this->mDb->select( 'templatelinks', array( 'tl_namespace', 'tl_title' ),
 670                         array( 'tl_from' => $this->mId ), __METHOD__, $this->mOptions );
 671                 $arr = array();
 672                 foreach ( $res as $row ) {
 673                         if ( !isset( $arr[$row->tl_namespace] ) ) {
 674                                 $arr[$row->tl_namespace] = array();
 675                         }
 676                         $arr[$row->tl_namespace][$row->tl_title] = 1;
 677                 }
 678
 679                 return $arr;
 680         }
 681
 682         /**
 683          * Get an array of existing images, image names in the keys
 684          *
 685          * @return array
 686          */
 687         private function getExistingImages() {
 688                 $res = $this->mDb->select( 'imagelinks', array( 'il_to' ),
 689                         array( 'il_from' => $this->mId ), __METHOD__, $this->mOptions );
 690                 $arr = array();
 691                 foreach ( $res as $row ) {
 692                         $arr[$row->il_to] = 1;
 693                 }
 694
 695                 return $arr;
 696         }
 697
 698         /**
 699          * Get an array of existing external links, URLs in the keys
 700          *
 701          * @return array
 702          */
 703         private function getExistingExternals() {
 704                 $res = $this->mDb->select( 'externallinks', array( 'el_to' ),
 705                         array( 'el_from' => $this->mId ), __METHOD__, $this->mOptions );
 706                 $arr = array();
 707                 foreach ( $res as $row ) {
 708                         $arr[$row->el_to] = 1;
 709                 }
 710
 711                 return $arr;
 712         }
 713
 714         /**
 715          * Get an array of existing categories, with the name in the key and sort key in the value.
 716          *
 717          * @return array
 718          */
 719         private function getExistingCategories() {
 720                 $res = $this->mDb->select( 'categorylinks', array( 'cl_to', 'cl_sortkey_prefix' ),
 721                         array( 'cl_from' => $this->mId ), __METHOD__, $this->mOptions );
 722                 $arr = array();
 723                 foreach ( $res as $row ) {
 724                         $arr[$row->cl_to] = $row->cl_sortkey_prefix;
 725                 }
 726
 727                 return $arr;
 728         }
 729
 730         /**
 731          * Get an array of existing interlanguage links, with the language code in the key and the
 732          * title in the value.
 733          *
 734          * @return array
 735          */
 736         private function getExistingInterlangs() {
 737                 $res = $this->mDb->select( 'langlinks', array( 'll_lang', 'll_title' ),
 738                         array( 'll_from' => $this->mId ), __METHOD__, $this->mOptions );
 739                 $arr = array();
 740                 foreach ( $res as $row ) {
 741                         $arr[$row->ll_lang] = $row->ll_title;
 742                 }
 743
 744                 return $arr;
 745         }
 746
 747         /**
 748          * Get an array of existing inline interwiki links, as a 2-D array
 749          * @return array (prefix => array(dbkey => 1))
 750          */
 751         protected function getExistingInterwikis() {
 752                 $res = $this->mDb->select( 'iwlinks', array( 'iwl_prefix', 'iwl_title' ),
 753                         array( 'iwl_from' => $this->mId ), __METHOD__, $this->mOptions );
 754                 $arr = array();
 755                 foreach ( $res as $row ) {
 756                         if ( !isset( $arr[$row->iwl_prefix] ) ) {
 757                                 $arr[$row->iwl_prefix] = array();
 758                         }
 759                         $arr[$row->iwl_prefix][$row->iwl_title] = 1;
 760                 }
 761
 762                 return $arr;
 763         }
 764
 765         /**
 766          * Get an array of existing categories, with the name in the key and sort key in the value.
 767          *
 768          * @return array of property names and values
 769          */
 770         private function getExistingProperties() {
 771                 $res = $this->mDb->select( 'page_props', array( 'pp_propname', 'pp_value' ),
 772                         array( 'pp_page' => $this->mId ), __METHOD__, $this->mOptions );
 773                 $arr = array();
 774                 foreach ( $res as $row ) {
 775                         $arr[$row->pp_propname] = $row->pp_value;
 776                 }
 777
 778                 return $arr;
 779         }
 780
 781         /**
 782          * Return the title object of the page being updated
 783          * @return Title
 784          */
 785         public function getTitle() {
 786                 return $this->mTitle;
 787         }
 788
 789         /**
 790          * Returns parser output
 791          * @since 1.19
 792          * @return ParserOutput
 793          */
 794         public function getParserOutput() {
 795                 return $this->mParserOutput;
 796         }
 797
 798         /**
 799          * Return the list of images used as generated by the parser
 800          * @return array
 801          */
 802         public function getImages() {
 803                 return $this->mImages;
 804         }
 805
 806         /**
 807          * Invalidate any necessary link lists related to page property changes
 808          * @param array $changed
 809          */
 810         private function invalidateProperties( $changed ) {
 811                 global $wgPagePropLinkInvalidations;
 812
 813                 foreach ( $changed as $name => $value ) {
 814                         if ( isset( $wgPagePropLinkInvalidations[$name] ) ) {
 815                                 $inv = $wgPagePropLinkInvalidations[$name];
 816                                 if ( !is_array( $inv ) ) {
 817                                         $inv = array( $inv );
 818                                 }
 819                                 foreach ( $inv as $table ) {
 820                                         $update = new HTMLCacheUpdate( $this->mTitle, $table );
 821                                         $update->doUpdate();
 822                                 }
 823                         }
 824                 }
 825         }
 826
 827         /**
 828          * Fetch page links added by this LinksUpdate.  Only available after the update is complete.
 829          * @since 1.22
 830          * @return null|array of Titles
 831          */
 832         public function getAddedLinks() {
 833                 if ( $this->linkInsertions === null ) {
 834                         return null;
 835                 }
 836                 $result = array();
 837                 foreach ( $this->linkInsertions as $insertion ) {
 838                         $result[] = Title::makeTitle( $insertion['pl_namespace'], $insertion['pl_title'] );
 839                 }
 840
 841                 return $result;
 842         }
 843
 844         /**
 845          * Fetch page links removed by this LinksUpdate.  Only available after the update is complete.
 846          * @since 1.22
 847          * @return null|array of Titles
 848          */
 849         public function getRemovedLinks() {
 850                 if ( $this->linkDeletions === null ) {
 851                         return null;
 852                 }
 853                 $result = array();
 854                 foreach ( $this->linkDeletions as $ns => $titles ) {
 855                         foreach ( $titles as $title => $unused ) {
 856                                 $result[] = Title::makeTitle( $ns, $title );
 857                         }
 858                 }
 859
 860                 return $result;
 861         }
 862
 863         /**
 864          * Update links table freshness
 865          */
 866         protected function updateLinksTimestamp() {
 867                 if ( $this->mId ) {
 868                         $this->mDb->update( 'page',
 869                                 array( 'page_links_updated' => $this->mDb->timestamp() ),
 870                                 array( 'page_id' => $this->mId ),
 871                                 __METHOD__
 872                         );
 873                 }
 874         }
 875 }
 876
 877 /**
 878  * Update object handling the cleanup of links tables after a page was deleted.
 879  **/
 880 class LinksDeletionUpdate extends SqlDataUpdate {
 881         /** @var WikiPage The WikiPage that was deleted */
 882         protected $mPage;
 883
 884         /**
 885          * Constructor
 886          *
 887          * @param WikiPage $page Page we are updating
 888          * @throws MWException
 889          */
 890         function __construct( WikiPage $page ) {
 891                 parent::__construct( false ); // no implicit transaction
 892
 893                 $this->mPage = $page;
 894
 895                 if ( !$page->exists() ) {
 896                         throw new MWException( "Page ID not known, perhaps the page doesn't exist?" );
 897                 }
 898         }
 899
 900         /**
 901          * Do some database updates after deletion
 902          */
 903         public function doUpdate() {
 904                 $title = $this->mPage->getTitle();
 905                 $id = $this->mPage->getId();
 906
 907                 # Delete restrictions for it
 908                 $this->mDb->delete( 'page_restrictions', array( 'pr_page' => $id ), __METHOD__ );
 909
 910                 # Fix category table counts
 911                 $cats = array();
 912                 $res = $this->mDb->select( 'categorylinks', 'cl_to', array( 'cl_from' => $id ), __METHOD__ );
 913
 914                 foreach ( $res as $row ) {
 915                         $cats[] = $row->cl_to;
 916                 }
 917
 918                 $this->mPage->updateCategoryCounts( array(), $cats );
 919
 920                 # If using cascading deletes, we can skip some explicit deletes
 921                 if ( !$this->mDb->cascadingDeletes() ) {
 922                         # Delete outgoing links
 923                         $this->mDb->delete( 'pagelinks', array( 'pl_from' => $id ), __METHOD__ );
 924                         $this->mDb->delete( 'imagelinks', array( 'il_from' => $id ), __METHOD__ );
 925                         $this->mDb->delete( 'categorylinks', array( 'cl_from' => $id ), __METHOD__ );
 926                         $this->mDb->delete( 'templatelinks', array( 'tl_from' => $id ), __METHOD__ );
 927                         $this->mDb->delete( 'externallinks', array( 'el_from' => $id ), __METHOD__ );
 928                         $this->mDb->delete( 'langlinks', array( 'll_from' => $id ), __METHOD__ );
 929                         $this->mDb->delete( 'iwlinks', array( 'iwl_from' => $id ), __METHOD__ );
 930                         $this->mDb->delete( 'redirect', array( 'rd_from' => $id ), __METHOD__ );
 931                         $this->mDb->delete( 'page_props', array( 'pp_page' => $id ), __METHOD__ );
 932                 }
 933
 934                 # If using cleanup triggers, we can skip some manual deletes
 935                 if ( !$this->mDb->cleanupTriggers() ) {
 936                         # Clean up recentchanges entries...
 937                         $this->mDb->delete( 'recentchanges',
 938                                 array( 'rc_type != ' . RC_LOG,
 939                                         'rc_namespace' => $title->getNamespace(),
 940                                         'rc_title' => $title->getDBkey() ),
 941                                 __METHOD__ );
 942                         $this->mDb->delete( 'recentchanges',
 943                                 array( 'rc_type != ' . RC_LOG, 'rc_cur_id' => $id ),
 944                                 __METHOD__ );
 945                 }
 946         }
 947
 948         /**
 949          * Update all the appropriate counts in the category table.
 950          * @param array $added Associative array of category name => sort key
 951          * @param array $deleted Associative array of category name => sort key
 952          */
 953         function updateCategoryCounts( $added, $deleted ) {
 954                 $a = WikiPage::factory( $this->mTitle );
 955                 $a->updateCategoryCounts(
 956                         array_keys( $added ), array_keys( $deleted )
 957                 );
 958         }
 959 }