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 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 Map of language codes to titles */
  56         public $mInterlangs;
  57
  58         /** @var array Map of arbitrary name to value */
  59         public $mProperties;
  60
  61         /** @var bool Whether to queue jobs for recursive updates */
  62         public $mRecursive;
  63
  64         /**
  65          * @var null|array Added links if calculated.
  66          */
  67         private $linkInsertions = null;
  68
  69         /**
  70          * @var null|array Deleted links if calculated.
  71          */
  72         private $linkDeletions = null;
  73
  74         /**
  75          * Constructor
  76          *
  77          * @param Title $title Title of the page we're updating
  78          * @param ParserOutput $parserOutput Output from a full parse of this page
  79          * @param bool $recursive Queue jobs for recursive updates?
  80          * @throws MWException
  81          */
  82         function __construct( $title, $parserOutput, $recursive = true ) {
  83                 parent::__construct( false ); // no implicit transaction
  84
  85                 if ( !( $title instanceof Title ) ) {
  86                         throw new MWException( "The calling convention to LinksUpdate::LinksUpdate() has changed. " .
  87                                 "Please see Article::editUpdates() for an invocation example.\n" );
  88                 }
  89
  90                 if ( !( $parserOutput instanceof ParserOutput ) ) {
  91                         throw new MWException( "The calling convention to LinksUpdate::__construct() has changed. " .
  92                                 "Please see WikiPage::doEditUpdates() for an invocation example.\n" );
  93                 }
  94
  95                 $this->mTitle = $title;
  96                 $this->mId = $title->getArticleID();
  97
  98                 if ( !$this->mId ) {
  99                         throw new MWException( "The Title object did not provide an article " .
 100                                 "ID. Perhaps the page doesn't exist?" );
 101                 }
 102
 103                 $this->mParserOutput = $parserOutput;
 104
 105                 $this->mLinks = $parserOutput->getLinks();
 106                 $this->mImages = $parserOutput->getImages();
 107                 $this->mTemplates = $parserOutput->getTemplates();
 108                 $this->mExternals = $parserOutput->getExternalLinks();
 109                 $this->mCategories = $parserOutput->getCategories();
 110                 $this->mProperties = $parserOutput->getProperties();
 111                 $this->mInterwikis = $parserOutput->getInterwikiLinks();
 112
 113                 # Convert the format of the interlanguage links
 114                 # I didn't want to change it in the ParserOutput, because that array is passed all
 115                 # the way back to the skin, so either a skin API break would be required, or an
 116                 # inefficient back-conversion.
 117                 $ill = $parserOutput->getLanguageLinks();
 118                 $this->mInterlangs = array();
 119                 foreach ( $ill as $link ) {
 120                         list( $key, $title ) = explode( ':', $link, 2 );
 121                         $this->mInterlangs[$key] = $title;
 122                 }
 123
 124                 foreach ( $this->mCategories as &$sortkey ) {
 125                         # If the sortkey is longer then 255 bytes,
 126                         # it truncated by DB, and then doesn't get
 127                         # matched when comparing existing vs current
 128                         # categories, causing bug 25254.
 129                         # Also. substr behaves weird when given "".
 130                         if ( $sortkey !== '' ) {
 131                                 $sortkey = substr( $sortkey, 0, 255 );
 132                         }
 133                 }
 134
 135                 $this->mRecursive = $recursive;
 136
 137                 Hooks::run( 'LinksUpdateConstructed', array( &$this ) );
 138         }
 139
 140         /**
 141          * Update link tables with outgoing links from an updated article
 142          */
 143         public function doUpdate() {
 144                 Hooks::run( 'LinksUpdate', array( &$this ) );
 145                 $this->doIncrementalUpdate();
 146                 Hooks::run( 'LinksUpdateComplete', array( &$this ) );
 147         }
 148
 149         protected function doIncrementalUpdate() {
 150
 151                 # Page links
 152                 $existing = $this->getExistingLinks();
 153                 $this->linkDeletions = $this->getLinkDeletions( $existing );
 154                 $this->linkInsertions = $this->getLinkInsertions( $existing );
 155                 $this->incrTableUpdate( 'pagelinks', 'pl', $this->linkDeletions, $this->linkInsertions );
 156
 157                 # Image links
 158                 $existing = $this->getExistingImages();
 159
 160                 $imageDeletes = $this->getImageDeletions( $existing );
 161                 $this->incrTableUpdate( 'imagelinks', 'il', $imageDeletes,
 162                         $this->getImageInsertions( $existing ) );
 163
 164                 # Invalidate all image description pages which had links added or removed
 165                 $imageUpdates = $imageDeletes + array_diff_key( $this->mImages, $existing );
 166                 $this->invalidateImageDescriptions( $imageUpdates );
 167
 168                 # External links
 169                 $existing = $this->getExistingExternals();
 170                 $this->incrTableUpdate( 'externallinks', 'el', $this->getExternalDeletions( $existing ),
 171                         $this->getExternalInsertions( $existing ) );
 172
 173                 # Language links
 174                 $existing = $this->getExistingInterlangs();
 175                 $this->incrTableUpdate( 'langlinks', 'll', $this->getInterlangDeletions( $existing ),
 176                         $this->getInterlangInsertions( $existing ) );
 177
 178                 # Inline interwiki links
 179                 $existing = $this->getExistingInterwikis();
 180                 $this->incrTableUpdate( 'iwlinks', 'iwl', $this->getInterwikiDeletions( $existing ),
 181                         $this->getInterwikiInsertions( $existing ) );
 182
 183                 # Template links
 184                 $existing = $this->getExistingTemplates();
 185                 $this->incrTableUpdate( 'templatelinks', 'tl', $this->getTemplateDeletions( $existing ),
 186                         $this->getTemplateInsertions( $existing ) );
 187
 188                 # Category links
 189                 $existing = $this->getExistingCategories();
 190
 191                 $categoryDeletes = $this->getCategoryDeletions( $existing );
 192
 193                 $this->incrTableUpdate( 'categorylinks', 'cl', $categoryDeletes,
 194                         $this->getCategoryInsertions( $existing ) );
 195
 196                 # Invalidate all categories which were added, deleted or changed (set symmetric difference)
 197                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 198                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 199                 $this->invalidateCategories( $categoryUpdates );
 200                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 201
 202                 # Page properties
 203                 $existing = $this->getExistingProperties();
 204
 205                 $propertiesDeletes = $this->getPropertyDeletions( $existing );
 206
 207                 $this->incrTableUpdate( 'page_props', 'pp', $propertiesDeletes,
 208                         $this->getPropertyInsertions( $existing ) );
 209
 210                 # Invalidate the necessary pages
 211                 $changed = $propertiesDeletes + array_diff_assoc( $this->mProperties, $existing );
 212                 $this->invalidateProperties( $changed );
 213
 214                 # Update the links table freshness for this title
 215                 $this->updateLinksTimestamp();
 216
 217                 # Refresh links of all pages including this page
 218                 # This will be in a separate transaction
 219                 if ( $this->mRecursive ) {
 220                         $this->queueRecursiveJobs();
 221                 }
 222
 223         }
 224
 225         /**
 226          * Queue recursive jobs for this page
 227          *
 228          * Which means do LinksUpdate on all pages that include the current page,
 229          * using the job queue.
 230          */
 231         function queueRecursiveJobs() {
 232                 self::queueRecursiveJobsForTable( $this->mTitle, 'templatelinks' );
 233                 if ( $this->mTitle->getNamespace() == NS_FILE ) {
 234                         // Process imagelinks in case the title is or was a redirect
 235                         self::queueRecursiveJobsForTable( $this->mTitle, 'imagelinks' );
 236                 }
 237         }
 238
 239         /**
 240          * Queue a RefreshLinks job for any table.
 241          *
 242          * @param Title $title Title to do job for
 243          * @param string $table Table to use (e.g. 'templatelinks')
 244          */
 245         public static function queueRecursiveJobsForTable( Title $title, $table ) {
 246                 if ( $title->getBacklinkCache()->hasLinks( $table ) ) {
 247                         $job = new RefreshLinksJob(
 248                                 $title,
 249                                 array(
 250                                         'table' => $table,
 251                                         'recursive' => true,
 252                                 ) + Job::newRootJobParams( // "overall" refresh links job info
 253                                         "refreshlinks:{$table}:{$title->getPrefixedText()}"
 254                                 )
 255                         );
 256                         JobQueueGroup::singleton()->push( $job );
 257                         JobQueueGroup::singleton()->deduplicateRootJob( $job );
 258                 }
 259         }
 260
 261         /**
 262          * @param array $cats
 263          */
 264         function invalidateCategories( $cats ) {
 265                 $this->invalidatePages( NS_CATEGORY, array_keys( $cats ) );
 266         }
 267
 268         /**
 269          * Update all the appropriate counts in the category table.
 270          * @param array $added Associative array of category name => sort key
 271          * @param array $deleted Associative array of category name => sort key
 272          */
 273         function updateCategoryCounts( $added, $deleted ) {
 274                 $a = WikiPage::factory( $this->mTitle );
 275                 $a->updateCategoryCounts(
 276                         array_keys( $added ), array_keys( $deleted )
 277                 );
 278         }
 279
 280         /**
 281          * @param array $images
 282          */
 283         function invalidateImageDescriptions( $images ) {
 284                 $this->invalidatePages( NS_FILE, array_keys( $images ) );
 285         }
 286
 287         /**
 288          * Update a table by doing a delete query then an insert query
 289          * @param string $table Table name
 290          * @param string $prefix Field name prefix
 291          * @param array $deletions
 292          * @param array $insertions Rows to insert
 293          */
 294         function incrTableUpdate( $table, $prefix, $deletions, $insertions ) {
 295                 if ( $table == 'page_props' ) {
 296                         $fromField = 'pp_page';
 297                 } else {
 298                         $fromField = "{$prefix}_from";
 299                 }
 300                 $where = array( $fromField => $this->mId );
 301                 if ( $table == 'pagelinks' || $table == 'templatelinks' || $table == 'iwlinks' ) {
 302                         if ( $table == 'iwlinks' ) {
 303                                 $baseKey = 'iwl_prefix';
 304                         } else {
 305                                 $baseKey = "{$prefix}_namespace";
 306                         }
 307                         $clause = $this->mDb->makeWhereFrom2d( $deletions, $baseKey, "{$prefix}_title" );
 308                         if ( $clause ) {
 309                                 $where[] = $clause;
 310                         } else {
 311                                 $where = false;
 312                         }
 313                 } else {
 314                         if ( $table == 'langlinks' ) {
 315                                 $toField = 'll_lang';
 316                         } elseif ( $table == 'page_props' ) {
 317                                 $toField = 'pp_propname';
 318                         } else {
 319                                 $toField = $prefix . '_to';
 320                         }
 321                         if ( count( $deletions ) ) {
 322                                 $where[$toField] = array_keys( $deletions );
 323                         } else {
 324                                 $where = false;
 325                         }
 326                 }
 327                 if ( $where ) {
 328                         $this->mDb->delete( $table, $where, __METHOD__ );
 329                 }
 330                 if ( count( $insertions ) ) {
 331                         $this->mDb->insert( $table, $insertions, __METHOD__, 'IGNORE' );
 332                         Hooks::run( 'LinksUpdateAfterInsert', array( $this, $table, $insertions ) );
 333                 }
 334         }
 335
 336         /**
 337          * Get an array of pagelinks insertions for passing to the DB
 338          * Skips the titles specified by the 2-D array $existing
 339          * @param array $existing
 340          * @return array
 341          */
 342         private function getLinkInsertions( $existing = array() ) {
 343                 $arr = array();
 344                 foreach ( $this->mLinks as $ns => $dbkeys ) {
 345                         $diffs = isset( $existing[$ns] )
 346                                 ? array_diff_key( $dbkeys, $existing[$ns] )
 347                                 : $dbkeys;
 348                         foreach ( $diffs as $dbk => $id ) {
 349                                 $arr[] = array(
 350                                         'pl_from' => $this->mId,
 351                                         'pl_from_namespace' => $this->mTitle->getNamespace(),
 352                                         'pl_namespace' => $ns,
 353                                         'pl_title' => $dbk
 354                                 );
 355                         }
 356                 }
 357
 358                 return $arr;
 359         }
 360
 361         /**
 362          * Get an array of template insertions. Like getLinkInsertions()
 363          * @param array $existing
 364          * @return array
 365          */
 366         private function getTemplateInsertions( $existing = array() ) {
 367                 $arr = array();
 368                 foreach ( $this->mTemplates as $ns => $dbkeys ) {
 369                         $diffs = isset( $existing[$ns] ) ? array_diff_key( $dbkeys, $existing[$ns] ) : $dbkeys;
 370                         foreach ( $diffs as $dbk => $id ) {
 371                                 $arr[] = array(
 372                                         'tl_from' => $this->mId,
 373                                         'tl_from_namespace' => $this->mTitle->getNamespace(),
 374                                         'tl_namespace' => $ns,
 375                                         'tl_title' => $dbk
 376                                 );
 377                         }
 378                 }
 379
 380                 return $arr;
 381         }
 382
 383         /**
 384          * Get an array of image insertions
 385          * Skips the names specified in $existing
 386          * @param array $existing
 387          * @return array
 388          */
 389         private function getImageInsertions( $existing = array() ) {
 390                 $arr = array();
 391                 $diffs = array_diff_key( $this->mImages, $existing );
 392                 foreach ( $diffs as $iname => $dummy ) {
 393                         $arr[] = array(
 394                                 'il_from' => $this->mId,
 395                                 'il_from_namespace' => $this->mTitle->getNamespace(),
 396                                 'il_to' => $iname
 397                         );
 398                 }
 399
 400                 return $arr;
 401         }
 402
 403         /**
 404          * Get an array of externallinks insertions. Skips the names specified in $existing
 405          * @param array $existing
 406          * @return array
 407          */
 408         private function getExternalInsertions( $existing = array() ) {
 409                 $arr = array();
 410                 $diffs = array_diff_key( $this->mExternals, $existing );
 411                 foreach ( $diffs as $url => $dummy ) {
 412                         foreach ( wfMakeUrlIndexes( $url ) as $index ) {
 413                                 $arr[] = array(
 414                                         'el_id' => $this->mDb->nextSequenceValue( 'externallinks_el_id_seq' ),
 415                                         'el_from' => $this->mId,
 416                                         'el_to' => $url,
 417                                         'el_index' => $index,
 418                                 );
 419                         }
 420                 }
 421
 422                 return $arr;
 423         }
 424
 425         /**
 426          * Get an array of category insertions
 427          *
 428          * @param array $existing Mapping existing category names to sort keys. If both
 429          * match a link in $this, the link will be omitted from the output
 430          *
 431          * @return array
 432          */
 433         private function getCategoryInsertions( $existing = array() ) {
 434                 global $wgContLang, $wgCategoryCollation;
 435                 $diffs = array_diff_assoc( $this->mCategories, $existing );
 436                 $arr = array();
 437                 foreach ( $diffs as $name => $prefix ) {
 438                         $nt = Title::makeTitleSafe( NS_CATEGORY, $name );
 439                         $wgContLang->findVariantLink( $name, $nt, true );
 440
 441                         if ( $this->mTitle->getNamespace() == NS_CATEGORY ) {
 442                                 $type = 'subcat';
 443                         } elseif ( $this->mTitle->getNamespace() == NS_FILE ) {
 444                                 $type = 'file';
 445                         } else {
 446                                 $type = 'page';
 447                         }
 448
 449                         # Treat custom sortkeys as a prefix, so that if multiple
 450                         # things are forced to sort as '*' or something, they'll
 451                         # sort properly in the category rather than in page_id
 452                         # order or such.
 453                         $sortkey = Collation::singleton()->getSortKey(
 454                                 $this->mTitle->getCategorySortkey( $prefix ) );
 455
 456                         $arr[] = array(
 457                                 'cl_from' => $this->mId,
 458                                 'cl_to' => $name,
 459                                 'cl_sortkey' => $sortkey,
 460                                 'cl_timestamp' => $this->mDb->timestamp(),
 461                                 'cl_sortkey_prefix' => $prefix,
 462                                 'cl_collation' => $wgCategoryCollation,
 463                                 'cl_type' => $type,
 464                         );
 465                 }
 466
 467                 return $arr;
 468         }
 469
 470         /**
 471          * Get an array of interlanguage link insertions
 472          *
 473          * @param array $existing Mapping existing language codes to titles
 474          *
 475          * @return array
 476          */
 477         private function getInterlangInsertions( $existing = array() ) {
 478                 $diffs = array_diff_assoc( $this->mInterlangs, $existing );
 479                 $arr = array();
 480                 foreach ( $diffs as $lang => $title ) {
 481                         $arr[] = array(
 482                                 'll_from' => $this->mId,
 483                                 'll_lang' => $lang,
 484                                 'll_title' => $title
 485                         );
 486                 }
 487
 488                 return $arr;
 489         }
 490
 491         /**
 492          * Get an array of page property insertions
 493          * @param array $existing
 494          * @return array
 495          */
 496         function getPropertyInsertions( $existing = array() ) {
 497                 $diffs = array_diff_assoc( $this->mProperties, $existing );
 498
 499                 $arr = array();
 500                 foreach ( array_keys( $diffs ) as $name ) {
 501                         $arr[] = $this->getPagePropRowData( $name );
 502                 }
 503
 504                 return $arr;
 505         }
 506
 507         /**
 508          * Returns an associative array to be used for inserting a row into
 509          * the page_props table. Besides the given property name, this will
 510          * include the page id from $this->mId and any property value from
 511          * $this->mProperties.
 512          *
 513          * The array returned will include the pp_sortkey field if this
 514          * is present in the database (as indicated by $wgPagePropsHaveSortkey).
 515          * The sortkey value is currently determined by getPropertySortKeyValue().
 516          *
 517          * @note this assumes that $this->mProperties[$prop] is defined.
 518          *
 519          * @param string $prop The name of the property.
 520          *
 521          * @return array
 522          */
 523         private function getPagePropRowData( $prop ) {
 524                 global $wgPagePropsHaveSortkey;
 525
 526                 $value = $this->mProperties[$prop];
 527
 528                 $row = array(
 529                         'pp_page' => $this->mId,
 530                         'pp_propname' => $prop,
 531                         'pp_value' => $value,
 532                 );
 533
 534                 if ( $wgPagePropsHaveSortkey ) {
 535                         $row['pp_sortkey'] = $this->getPropertySortKeyValue( $value );
 536                 }
 537
 538                 return $row;
 539         }
 540
 541         /**
 542          * Determines the sort key for the given property value.
 543          * This will return $value if it is a float or int,
 544          * 1 or resp. 0 if it is a bool, and null otherwise.
 545          *
 546          * @note In the future, we may allow the sortkey to be specified explicitly
 547          *       in ParserOutput::setProperty.
 548          *
 549          * @param mixed $value
 550          *
 551          * @return float|null
 552          */
 553         private function getPropertySortKeyValue( $value ) {
 554                 if ( is_int( $value ) || is_float( $value ) || is_bool( $value ) ) {
 555                         return floatval( $value );
 556                 }
 557
 558                 return null;
 559         }
 560
 561         /**
 562          * Get an array of interwiki insertions for passing to the DB
 563          * Skips the titles specified by the 2-D array $existing
 564          * @param array $existing
 565          * @return array
 566          */
 567         private function getInterwikiInsertions( $existing = array() ) {
 568                 $arr = array();
 569                 foreach ( $this->mInterwikis as $prefix => $dbkeys ) {
 570                         $diffs = isset( $existing[$prefix] )
 571                                 ? array_diff_key( $dbkeys, $existing[$prefix] )
 572                                 : $dbkeys;
 573
 574                         foreach ( $diffs as $dbk => $id ) {
 575                                 $arr[] = array(
 576                                         'iwl_from' => $this->mId,
 577                                         'iwl_prefix' => $prefix,
 578                                         'iwl_title' => $dbk
 579                                 );
 580                         }
 581                 }
 582
 583                 return $arr;
 584         }
 585
 586         /**
 587          * Given an array of existing links, returns those links which are not in $this
 588          * and thus should be deleted.
 589          * @param array $existing
 590          * @return array
 591          */
 592         private function getLinkDeletions( $existing ) {
 593                 $del = array();
 594                 foreach ( $existing as $ns => $dbkeys ) {
 595                         if ( isset( $this->mLinks[$ns] ) ) {
 596                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mLinks[$ns] );
 597                         } else {
 598                                 $del[$ns] = $existing[$ns];
 599                         }
 600                 }
 601
 602                 return $del;
 603         }
 604
 605         /**
 606          * Given an array of existing templates, returns those templates which are not in $this
 607          * and thus should be deleted.
 608          * @param array $existing
 609          * @return array
 610          */
 611         private function getTemplateDeletions( $existing ) {
 612                 $del = array();
 613                 foreach ( $existing as $ns => $dbkeys ) {
 614                         if ( isset( $this->mTemplates[$ns] ) ) {
 615                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mTemplates[$ns] );
 616                         } else {
 617                                 $del[$ns] = $existing[$ns];
 618                         }
 619                 }
 620
 621                 return $del;
 622         }
 623
 624         /**
 625          * Given an array of existing images, returns those images which are not in $this
 626          * and thus should be deleted.
 627          * @param array $existing
 628          * @return array
 629          */
 630         private function getImageDeletions( $existing ) {
 631                 return array_diff_key( $existing, $this->mImages );
 632         }
 633
 634         /**
 635          * Given an array of existing external links, returns those links which are not
 636          * in $this and thus should be deleted.
 637          * @param array $existing
 638          * @return array
 639          */
 640         private function getExternalDeletions( $existing ) {
 641                 return array_diff_key( $existing, $this->mExternals );
 642         }
 643
 644         /**
 645          * Given an array of existing categories, returns those categories which are not in $this
 646          * and thus should be deleted.
 647          * @param array $existing
 648          * @return array
 649          */
 650         private function getCategoryDeletions( $existing ) {
 651                 return array_diff_assoc( $existing, $this->mCategories );
 652         }
 653
 654         /**
 655          * Given an array of existing interlanguage links, returns those links which are not
 656          * in $this and thus should be deleted.
 657          * @param array $existing
 658          * @return array
 659          */
 660         private function getInterlangDeletions( $existing ) {
 661                 return array_diff_assoc( $existing, $this->mInterlangs );
 662         }
 663
 664         /**
 665          * Get array of properties which should be deleted.
 666          * @param array $existing
 667          * @return array
 668          */
 669         function getPropertyDeletions( $existing ) {
 670                 return array_diff_assoc( $existing, $this->mProperties );
 671         }
 672
 673         /**
 674          * Given an array of existing interwiki links, returns those links which are not in $this
 675          * and thus should be deleted.
 676          * @param array $existing
 677          * @return array
 678          */
 679         private function getInterwikiDeletions( $existing ) {
 680                 $del = array();
 681                 foreach ( $existing as $prefix => $dbkeys ) {
 682                         if ( isset( $this->mInterwikis[$prefix] ) ) {
 683                                 $del[$prefix] = array_diff_key( $existing[$prefix], $this->mInterwikis[$prefix] );
 684                         } else {
 685                                 $del[$prefix] = $existing[$prefix];
 686                         }
 687                 }
 688
 689                 return $del;
 690         }
 691
 692         /**
 693          * Get an array of existing links, as a 2-D array
 694          *
 695          * @return array
 696          */
 697         private function getExistingLinks() {
 698                 $res = $this->mDb->select( 'pagelinks', array( 'pl_namespace', 'pl_title' ),
 699                         array( 'pl_from' => $this->mId ), __METHOD__, $this->mOptions );
 700                 $arr = array();
 701                 foreach ( $res as $row ) {
 702                         if ( !isset( $arr[$row->pl_namespace] ) ) {
 703                                 $arr[$row->pl_namespace] = array();
 704                         }
 705                         $arr[$row->pl_namespace][$row->pl_title] = 1;
 706                 }
 707
 708                 return $arr;
 709         }
 710
 711         /**
 712          * Get an array of existing templates, as a 2-D array
 713          *
 714          * @return array
 715          */
 716         private function getExistingTemplates() {
 717                 $res = $this->mDb->select( 'templatelinks', array( 'tl_namespace', 'tl_title' ),
 718                         array( 'tl_from' => $this->mId ), __METHOD__, $this->mOptions );
 719                 $arr = array();
 720                 foreach ( $res as $row ) {
 721                         if ( !isset( $arr[$row->tl_namespace] ) ) {
 722                                 $arr[$row->tl_namespace] = array();
 723                         }
 724                         $arr[$row->tl_namespace][$row->tl_title] = 1;
 725                 }
 726
 727                 return $arr;
 728         }
 729
 730         /**
 731          * Get an array of existing images, image names in the keys
 732          *
 733          * @return array
 734          */
 735         private function getExistingImages() {
 736                 $res = $this->mDb->select( 'imagelinks', array( 'il_to' ),
 737                         array( 'il_from' => $this->mId ), __METHOD__, $this->mOptions );
 738                 $arr = array();
 739                 foreach ( $res as $row ) {
 740                         $arr[$row->il_to] = 1;
 741                 }
 742
 743                 return $arr;
 744         }
 745
 746         /**
 747          * Get an array of existing external links, URLs in the keys
 748          *
 749          * @return array
 750          */
 751         private function getExistingExternals() {
 752                 $res = $this->mDb->select( 'externallinks', array( 'el_to' ),
 753                         array( 'el_from' => $this->mId ), __METHOD__, $this->mOptions );
 754                 $arr = array();
 755                 foreach ( $res as $row ) {
 756                         $arr[$row->el_to] = 1;
 757                 }
 758
 759                 return $arr;
 760         }
 761
 762         /**
 763          * Get an array of existing categories, with the name in the key and sort key in the value.
 764          *
 765          * @return array
 766          */
 767         private function getExistingCategories() {
 768                 $res = $this->mDb->select( 'categorylinks', array( 'cl_to', 'cl_sortkey_prefix' ),
 769                         array( 'cl_from' => $this->mId ), __METHOD__, $this->mOptions );
 770                 $arr = array();
 771                 foreach ( $res as $row ) {
 772                         $arr[$row->cl_to] = $row->cl_sortkey_prefix;
 773                 }
 774
 775                 return $arr;
 776         }
 777
 778         /**
 779          * Get an array of existing interlanguage links, with the language code in the key and the
 780          * title in the value.
 781          *
 782          * @return array
 783          */
 784         private function getExistingInterlangs() {
 785                 $res = $this->mDb->select( 'langlinks', array( 'll_lang', 'll_title' ),
 786                         array( 'll_from' => $this->mId ), __METHOD__, $this->mOptions );
 787                 $arr = array();
 788                 foreach ( $res as $row ) {
 789                         $arr[$row->ll_lang] = $row->ll_title;
 790                 }
 791
 792                 return $arr;
 793         }
 794
 795         /**
 796          * Get an array of existing inline interwiki links, as a 2-D array
 797          * @return array (prefix => array(dbkey => 1))
 798          */
 799         protected function getExistingInterwikis() {
 800                 $res = $this->mDb->select( 'iwlinks', array( 'iwl_prefix', 'iwl_title' ),
 801                         array( 'iwl_from' => $this->mId ), __METHOD__, $this->mOptions );
 802                 $arr = array();
 803                 foreach ( $res as $row ) {
 804                         if ( !isset( $arr[$row->iwl_prefix] ) ) {
 805                                 $arr[$row->iwl_prefix] = array();
 806                         }
 807                         $arr[$row->iwl_prefix][$row->iwl_title] = 1;
 808                 }
 809
 810                 return $arr;
 811         }
 812
 813         /**
 814          * Get an array of existing categories, with the name in the key and sort key in the value.
 815          *
 816          * @return array Array of property names and values
 817          */
 818         private function getExistingProperties() {
 819                 $res = $this->mDb->select( 'page_props', array( 'pp_propname', 'pp_value' ),
 820                         array( 'pp_page' => $this->mId ), __METHOD__, $this->mOptions );
 821                 $arr = array();
 822                 foreach ( $res as $row ) {
 823                         $arr[$row->pp_propname] = $row->pp_value;
 824                 }
 825
 826                 return $arr;
 827         }
 828
 829         /**
 830          * Return the title object of the page being updated
 831          * @return Title
 832          */
 833         public function getTitle() {
 834                 return $this->mTitle;
 835         }
 836
 837         /**
 838          * Returns parser output
 839          * @since 1.19
 840          * @return ParserOutput
 841          */
 842         public function getParserOutput() {
 843                 return $this->mParserOutput;
 844         }
 845
 846         /**
 847          * Return the list of images used as generated by the parser
 848          * @return array
 849          */
 850         public function getImages() {
 851                 return $this->mImages;
 852         }
 853
 854         /**
 855          * Invalidate any necessary link lists related to page property changes
 856          * @param array $changed
 857          */
 858         private function invalidateProperties( $changed ) {
 859                 global $wgPagePropLinkInvalidations;
 860
 861                 foreach ( $changed as $name => $value ) {
 862                         if ( isset( $wgPagePropLinkInvalidations[$name] ) ) {
 863                                 $inv = $wgPagePropLinkInvalidations[$name];
 864                                 if ( !is_array( $inv ) ) {
 865                                         $inv = array( $inv );
 866                                 }
 867                                 foreach ( $inv as $table ) {
 868                                         $update = new HTMLCacheUpdate( $this->mTitle, $table );
 869                                         $update->doUpdate();
 870                                 }
 871                         }
 872                 }
 873         }
 874
 875         /**
 876          * Fetch page links added by this LinksUpdate.  Only available after the update is complete.
 877          * @since 1.22
 878          * @return null|array Array of Titles
 879          */
 880         public function getAddedLinks() {
 881                 if ( $this->linkInsertions === null ) {
 882                         return null;
 883                 }
 884                 $result = array();
 885                 foreach ( $this->linkInsertions as $insertion ) {
 886                         $result[] = Title::makeTitle( $insertion['pl_namespace'], $insertion['pl_title'] );
 887                 }
 888
 889                 return $result;
 890         }
 891
 892         /**
 893          * Fetch page links removed by this LinksUpdate.  Only available after the update is complete.
 894          * @since 1.22
 895          * @return null|array Array of Titles
 896          */
 897         public function getRemovedLinks() {
 898                 if ( $this->linkDeletions === null ) {
 899                         return null;
 900                 }
 901                 $result = array();
 902                 foreach ( $this->linkDeletions as $ns => $titles ) {
 903                         foreach ( $titles as $title => $unused ) {
 904                                 $result[] = Title::makeTitle( $ns, $title );
 905                         }
 906                 }
 907
 908                 return $result;
 909         }
 910
 911         /**
 912          * Update links table freshness
 913          */
 914         protected function updateLinksTimestamp() {
 915                 if ( $this->mId ) {
 916                         // The link updates made here only reflect the freshness of the parser output
 917                         $timestamp = $this->mParserOutput->getCacheTime();
 918                         $this->mDb->update( 'page',
 919                                 array( 'page_links_updated' => $this->mDb->timestamp( $timestamp ) ),
 920                                 array( 'page_id' => $this->mId ),
 921                                 __METHOD__
 922                         );
 923                 }
 924         }
 925 }
 926
 927 /**
 928  * Update object handling the cleanup of links tables after a page was deleted.
 929  **/
 930 class LinksDeletionUpdate extends SqlDataUpdate {
 931         /** @var WikiPage The WikiPage that was deleted */
 932         protected $mPage;
 933
 934         /**
 935          * Constructor
 936          *
 937          * @param WikiPage $page Page we are updating
 938          * @throws MWException
 939          */
 940         function __construct( WikiPage $page ) {
 941                 parent::__construct( false ); // no implicit transaction
 942
 943                 $this->mPage = $page;
 944
 945                 if ( !$page->exists() ) {
 946                         throw new MWException( "Page ID not known, perhaps the page doesn't exist?" );
 947                 }
 948         }
 949
 950         /**
 951          * Do some database updates after deletion
 952          */
 953         public function doUpdate() {
 954                 $title = $this->mPage->getTitle();
 955                 $id = $this->mPage->getId();
 956
 957                 # Delete restrictions for it
 958                 $this->mDb->delete( 'page_restrictions', array( 'pr_page' => $id ), __METHOD__ );
 959
 960                 # Fix category table counts
 961                 $cats = array();
 962                 $res = $this->mDb->select( 'categorylinks', 'cl_to', array( 'cl_from' => $id ), __METHOD__ );
 963
 964                 foreach ( $res as $row ) {
 965                         $cats[] = $row->cl_to;
 966                 }
 967
 968                 $this->mPage->updateCategoryCounts( array(), $cats );
 969
 970                 # If using cascading deletes, we can skip some explicit deletes
 971                 if ( !$this->mDb->cascadingDeletes() ) {
 972                         # Delete outgoing links
 973                         $this->mDb->delete( 'pagelinks', array( 'pl_from' => $id ), __METHOD__ );
 974                         $this->mDb->delete( 'imagelinks', array( 'il_from' => $id ), __METHOD__ );
 975                         $this->mDb->delete( 'categorylinks', array( 'cl_from' => $id ), __METHOD__ );
 976                         $this->mDb->delete( 'templatelinks', array( 'tl_from' => $id ), __METHOD__ );
 977                         $this->mDb->delete( 'externallinks', array( 'el_from' => $id ), __METHOD__ );
 978                         $this->mDb->delete( 'langlinks', array( 'll_from' => $id ), __METHOD__ );
 979                         $this->mDb->delete( 'iwlinks', array( 'iwl_from' => $id ), __METHOD__ );
 980                         $this->mDb->delete( 'redirect', array( 'rd_from' => $id ), __METHOD__ );
 981                         $this->mDb->delete( 'page_props', array( 'pp_page' => $id ), __METHOD__ );
 982                 }
 983
 984                 # If using cleanup triggers, we can skip some manual deletes
 985                 if ( !$this->mDb->cleanupTriggers() ) {
 986                         # Clean up recentchanges entries...
 987                         $this->mDb->delete( 'recentchanges',
 988                                 array( 'rc_type != ' . RC_LOG,
 989                                         'rc_namespace' => $title->getNamespace(),
 990                                         'rc_title' => $title->getDBkey() ),
 991                                 __METHOD__ );
 992                         $this->mDb->delete( 'recentchanges',
 993                                 array( 'rc_type != ' . RC_LOG, 'rc_cur_id' => $id ),
 994                                 __METHOD__ );
 995                 }
 996         }
 997
 998         /**
 999          * Update all the appropriate counts in the category table.
1000          * @param array $added Associative array of category name => sort key
1001          * @param array $deleted Associative array of category name => sort key
1002          */
1003         function updateCategoryCounts( $added, $deleted ) {
1004                 $a = WikiPage::factory( $this->mTitle );
1005                 $a->updateCategoryCounts(
1006                         array_keys( $added ), array_keys( $deleted )
1007                 );
1008         }
1009 }