includes/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
  30         // @todo: make members protected, but make sure extensions don't break
  31
  32         public $mId,         //!< Page ID of the article linked from
  33                 $mTitle,         //!< Title object of the article linked from
  34                 $mParserOutput,  //!< Parser output
  35                 $mLinks,         //!< Map of title strings to IDs for the links in the document
  36                 $mImages,        //!< DB keys of the images used, in the array key only
  37                 $mTemplates,     //!< Map of title strings to IDs for the template references, including broken ones
  38                 $mExternals,     //!< URLs of external links, array key only
  39                 $mCategories,    //!< Map of category names to sort keys
  40                 $mInterlangs,    //!< Map of language codes to titles
  41                 $mProperties,    //!< Map of arbitrary name to value
  42                 $mRecursive;     //!< Whether to queue jobs for recursive updates
  43
  44         /**
  45          * Constructor
  46          *
  47          * @param $title Title of the page we're updating
  48          * @param $parserOutput ParserOutput: output from a full parse of this page
  49          * @param $recursive Boolean: queue jobs for recursive updates?
  50          */
  51         function __construct( $title, $parserOutput, $recursive = true ) {
  52                 parent::__construct( );
  53
  54                 if ( !( $title instanceof Title ) ) {
  55                         throw new MWException( "The calling convention to LinksUpdate::LinksUpdate() has changed. " .
  56                                 "Please see Article::editUpdates() for an invocation example.\n" );
  57                 }
  58
  59                 if ( !( $parserOutput instanceof ParserOutput ) ) {
  60                         throw new MWException( "The calling convention to LinksUpdate::__construct() has changed. " .
  61                                 "Please see WikiPage::doEditUpdates() for an invocation example.\n" );
  62                 }
  63
  64                 $this->mTitle = $title;
  65                 $this->mId = $title->getArticleID();
  66                 assert( $this->mId > 0 );
  67
  68                 $this->mParserOutput = $parserOutput;
  69
  70                 $this->mLinks = $parserOutput->getLinks();
  71                 $this->mImages = $parserOutput->getImages();
  72                 $this->mTemplates = $parserOutput->getTemplates();
  73                 $this->mExternals = $parserOutput->getExternalLinks();
  74                 $this->mCategories = $parserOutput->getCategories();
  75                 $this->mProperties = $parserOutput->getProperties();
  76                 $this->mInterwikis = $parserOutput->getInterwikiLinks();
  77
  78                 # Convert the format of the interlanguage links
  79                 # I didn't want to change it in the ParserOutput, because that array is passed all
  80                 # the way back to the skin, so either a skin API break would be required, or an
  81                 # inefficient back-conversion.
  82                 $ill = $parserOutput->getLanguageLinks();
  83                 $this->mInterlangs = array();
  84                 foreach ( $ill as $link ) {
  85                         list( $key, $title ) = explode( ':', $link, 2 );
  86                         $this->mInterlangs[$key] = $title;
  87                 }
  88
  89                 foreach ( $this->mCategories as &$sortkey ) {
  90                         # If the sortkey is longer then 255 bytes,
  91                         # it truncated by DB, and then doesn't get
  92                         # matched when comparing existing vs current
  93                         # categories, causing bug 25254.
  94                         # Also. substr behaves weird when given "".
  95                         if ( $sortkey !== '' ) {
  96                                 $sortkey = substr( $sortkey, 0, 255 );
  97                         }
  98                 }
  99
 100                 $this->mRecursive = $recursive;
 101
 102                 wfRunHooks( 'LinksUpdateConstructed', array( &$this ) );
 103         }
 104
 105         /**
 106          * Update link tables with outgoing links from an updated article
 107          */
 108         public function doUpdate() {
 109                 global $wgUseDumbLinkUpdate;
 110
 111                 wfRunHooks( 'LinksUpdate', array( &$this ) );
 112                 if ( $wgUseDumbLinkUpdate ) {
 113                         $this->doDumbUpdate();
 114                 } else {
 115                         $this->doIncrementalUpdate();
 116                 }
 117                 wfRunHooks( 'LinksUpdateComplete', array( &$this ) );
 118         }
 119
 120         protected function doIncrementalUpdate() {
 121                 wfProfileIn( __METHOD__ );
 122
 123                 # Page links
 124                 $existing = $this->getExistingLinks();
 125                 $this->incrTableUpdate( 'pagelinks', 'pl', $this->getLinkDeletions( $existing ),
 126                         $this->getLinkInsertions( $existing ) );
 127
 128                 # Image links
 129                 $existing = $this->getExistingImages();
 130
 131                 $imageDeletes = $this->getImageDeletions( $existing );
 132                 $this->incrTableUpdate( 'imagelinks', 'il', $imageDeletes,
 133                         $this->getImageInsertions( $existing ) );
 134
 135                 # Invalidate all image description pages which had links added or removed
 136                 $imageUpdates = $imageDeletes + array_diff_key( $this->mImages, $existing );
 137                 $this->invalidateImageDescriptions( $imageUpdates );
 138
 139                 # External links
 140                 $existing = $this->getExistingExternals();
 141                 $this->incrTableUpdate( 'externallinks', 'el', $this->getExternalDeletions( $existing ),
 142                         $this->getExternalInsertions( $existing ) );
 143
 144                 # Language links
 145                 $existing = $this->getExistingInterlangs();
 146                 $this->incrTableUpdate( 'langlinks', 'll', $this->getInterlangDeletions( $existing ),
 147                         $this->getInterlangInsertions( $existing ) );
 148
 149                 # Inline interwiki links
 150                 $existing = $this->getExistingInterwikis();
 151                 $this->incrTableUpdate( 'iwlinks', 'iwl', $this->getInterwikiDeletions( $existing ),
 152                         $this->getInterwikiInsertions( $existing ) );
 153
 154                 # Template links
 155                 $existing = $this->getExistingTemplates();
 156                 $this->incrTableUpdate( 'templatelinks', 'tl', $this->getTemplateDeletions( $existing ),
 157                         $this->getTemplateInsertions( $existing ) );
 158
 159                 # Category links
 160                 $existing = $this->getExistingCategories();
 161
 162                 $categoryDeletes = $this->getCategoryDeletions( $existing );
 163
 164                 $this->incrTableUpdate( 'categorylinks', 'cl', $categoryDeletes,
 165                         $this->getCategoryInsertions( $existing ) );
 166
 167                 # Invalidate all categories which were added, deleted or changed (set symmetric difference)
 168                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 169                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 170                 $this->invalidateCategories( $categoryUpdates );
 171                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 172
 173                 # Page properties
 174                 $existing = $this->getExistingProperties();
 175
 176                 $propertiesDeletes = $this->getPropertyDeletions( $existing );
 177
 178                 $this->incrTableUpdate( 'page_props', 'pp', $propertiesDeletes,
 179                         $this->getPropertyInsertions( $existing ) );
 180
 181                 # Invalidate the necessary pages
 182                 $changed = $propertiesDeletes + array_diff_assoc( $this->mProperties, $existing );
 183                 $this->invalidateProperties( $changed );
 184
 185                 # Refresh links of all pages including this page
 186                 # This will be in a separate transaction
 187                 if ( $this->mRecursive ) {
 188                         $this->queueRecursiveJobs();
 189                 }
 190
 191                 wfProfileOut( __METHOD__ );
 192         }
 193
 194         /**
 195          * Link update which clears the previous entries and inserts new ones
 196          * May be slower or faster depending on level of lock contention and write speed of DB
 197          * Also useful where link table corruption needs to be repaired, e.g. in refreshLinks.php
 198          */
 199         protected function doDumbUpdate() {
 200                 wfProfileIn( __METHOD__ );
 201
 202                 # Refresh category pages and image description pages
 203                 $existing = $this->getExistingCategories();
 204                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 205                 $categoryDeletes = array_diff_assoc( $existing, $this->mCategories );
 206                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 207                 $existing = $this->getExistingImages();
 208                 $imageUpdates = array_diff_key( $existing, $this->mImages ) + array_diff_key( $this->mImages, $existing );
 209
 210                 $this->dumbTableUpdate( 'pagelinks',     $this->getLinkInsertions(),     'pl_from' );
 211                 $this->dumbTableUpdate( 'imagelinks',    $this->getImageInsertions(),    'il_from' );
 212                 $this->dumbTableUpdate( 'categorylinks', $this->getCategoryInsertions(), 'cl_from' );
 213                 $this->dumbTableUpdate( 'templatelinks', $this->getTemplateInsertions(), 'tl_from' );
 214                 $this->dumbTableUpdate( 'externallinks', $this->getExternalInsertions(), 'el_from' );
 215                 $this->dumbTableUpdate( 'langlinks',     $this->getInterlangInsertions(),'ll_from' );
 216                 $this->dumbTableUpdate( 'iwlinks',       $this->getInterwikiInsertions(),'iwl_from' );
 217                 $this->dumbTableUpdate( 'page_props',    $this->getPropertyInsertions(), 'pp_page' );
 218
 219                 # Update the cache of all the category pages and image description
 220                 # pages which were changed, and fix the category table count
 221                 $this->invalidateCategories( $categoryUpdates );
 222                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 223                 $this->invalidateImageDescriptions( $imageUpdates );
 224
 225                 # Refresh links of all pages including this page
 226                 # This will be in a separate transaction
 227                 if ( $this->mRecursive ) {
 228                         $this->queueRecursiveJobs();
 229                 }
 230
 231                 wfProfileOut( __METHOD__ );
 232         }
 233
 234         function queueRecursiveJobs() {
 235                 global $wgUpdateRowsPerJob;
 236                 wfProfileIn( __METHOD__ );
 237
 238                 $cache = $this->mTitle->getBacklinkCache();
 239                 $batches = $cache->partition( 'templatelinks', $wgUpdateRowsPerJob );
 240                 if ( !$batches ) {
 241                         wfProfileOut( __METHOD__ );
 242                         return;
 243                 }
 244                 $jobs = array();
 245                 foreach ( $batches as $batch ) {
 246                         list( $start, $end ) = $batch;
 247                         $params = array(
 248                                 'table' => 'templatelinks',
 249                                 'start' => $start,
 250                                 'end' => $end,
 251                         );
 252                         $jobs[] = new RefreshLinksJob2( $this->mTitle, $params );
 253                 }
 254                 Job::batchInsert( $jobs );
 255
 256                 wfProfileOut( __METHOD__ );
 257         }
 258
 259         /**
 260          * @param $cats
 261          */
 262         function invalidateCategories( $cats ) {
 263                 $this->invalidatePages( NS_CATEGORY, array_keys( $cats ) );
 264         }
 265
 266         /**
 267          * Update all the appropriate counts in the category table.
 268          * @param $added array associative array of category name => sort key
 269          * @param $deleted array associative array of category name => sort key
 270          */
 271         function updateCategoryCounts( $added, $deleted ) {
 272                 $a = WikiPage::factory( $this->mTitle );
 273                 $a->updateCategoryCounts(
 274                         array_keys( $added ), array_keys( $deleted )
 275                 );
 276         }
 277
 278         /**
 279          * @param $images
 280          */
 281         function invalidateImageDescriptions( $images ) {
 282                 $this->invalidatePages( NS_FILE, array_keys( $images ) );
 283         }
 284
 285         /**
 286          * @param $table
 287          * @param $insertions
 288          * @param $fromField
 289          */
 290         private function dumbTableUpdate( $table, $insertions, $fromField ) {
 291                 $this->mDb->delete( $table, array( $fromField => $this->mId ), __METHOD__ );
 292                 if ( count( $insertions ) ) {
 293                         # The link array was constructed without FOR UPDATE, so there may
 294                         # be collisions.  This may cause minor link table inconsistencies,
 295                         # which is better than crippling the site with lock contention.
 296                         $this->mDb->insert( $table, $insertions, __METHOD__, array( 'IGNORE' ) );
 297                 }
 298         }
 299
 300         /**
 301          * Update a table by doing a delete query then an insert query
 302          * @param $table
 303          * @param $prefix
 304          * @param $deletions
 305          * @param $insertions
 306          */
 307         function incrTableUpdate( $table, $prefix, $deletions, $insertions ) {
 308                 if ( $table == 'page_props' ) {
 309                         $fromField = 'pp_page';
 310                 } else {
 311                         $fromField = "{$prefix}_from";
 312                 }
 313                 $where = array( $fromField => $this->mId );
 314                 if ( $table == 'pagelinks' || $table == 'templatelinks' || $table == 'iwlinks' ) {
 315                         if ( $table == 'iwlinks' ) {
 316                                 $baseKey = 'iwl_prefix';
 317                         } else {
 318                                 $baseKey = "{$prefix}_namespace";
 319                         }
 320                         $clause = $this->mDb->makeWhereFrom2d( $deletions, $baseKey, "{$prefix}_title" );
 321                         if ( $clause ) {
 322                                 $where[] = $clause;
 323                         } else {
 324                                 $where = false;
 325                         }
 326                 } else {
 327                         if ( $table == 'langlinks' ) {
 328                                 $toField = 'll_lang';
 329                         } elseif ( $table == 'page_props' ) {
 330                                 $toField = 'pp_propname';
 331                         } else {
 332                                 $toField = $prefix . '_to';
 333                         }
 334                         if ( count( $deletions ) ) {
 335                                 $where[] = "$toField IN (" . $this->mDb->makeList( array_keys( $deletions ) ) . ')';
 336                         } else {
 337                                 $where = false;
 338                         }
 339                 }
 340                 if ( $where ) {
 341                         $this->mDb->delete( $table, $where, __METHOD__ );
 342                 }
 343                 if ( count( $insertions ) ) {
 344                         $this->mDb->insert( $table, $insertions, __METHOD__, 'IGNORE' );
 345                 }
 346         }
 347
 348         /**
 349          * Get an array of pagelinks insertions for passing to the DB
 350          * Skips the titles specified by the 2-D array $existing
 351          * @param $existing array
 352          * @return array
 353          */
 354         private function getLinkInsertions( $existing = array() ) {
 355                 $arr = array();
 356                 foreach( $this->mLinks as $ns => $dbkeys ) {
 357                         $diffs = isset( $existing[$ns] )
 358                                 ? array_diff_key( $dbkeys, $existing[$ns] )
 359                                 : $dbkeys;
 360                         foreach ( $diffs as $dbk => $id ) {
 361                                 $arr[] = array(
 362                                         'pl_from'      => $this->mId,
 363                                         'pl_namespace' => $ns,
 364                                         'pl_title'     => $dbk
 365                                 );
 366                         }
 367                 }
 368                 return $arr;
 369         }
 370
 371         /**
 372          * Get an array of template insertions. Like getLinkInsertions()
 373          * @param $existing array
 374          * @return array
 375          */
 376         private function getTemplateInsertions( $existing = array() ) {
 377                 $arr = array();
 378                 foreach( $this->mTemplates as $ns => $dbkeys ) {
 379                         $diffs = isset( $existing[$ns] ) ? array_diff_key( $dbkeys, $existing[$ns] ) : $dbkeys;
 380                         foreach ( $diffs as $dbk => $id ) {
 381                                 $arr[] = array(
 382                                         'tl_from'      => $this->mId,
 383                                         'tl_namespace' => $ns,
 384                                         'tl_title'     => $dbk
 385                                 );
 386                         }
 387                 }
 388                 return $arr;
 389         }
 390
 391         /**
 392          * Get an array of image insertions
 393          * Skips the names specified in $existing
 394          * @param $existing array
 395          * @return array
 396          */
 397         private function getImageInsertions( $existing = array() ) {
 398                 $arr = array();
 399                 $diffs = array_diff_key( $this->mImages, $existing );
 400                 foreach( $diffs as $iname => $dummy ) {
 401                         $arr[] = array(
 402                                 'il_from' => $this->mId,
 403                                 'il_to'   => $iname
 404                         );
 405                 }
 406                 return $arr;
 407         }
 408
 409         /**
 410          * Get an array of externallinks insertions. Skips the names specified in $existing
 411          * @param $existing array
 412          * @return array
 413          */
 414         private function getExternalInsertions( $existing = array() ) {
 415                 $arr = array();
 416                 $diffs = array_diff_key( $this->mExternals, $existing );
 417                 foreach( $diffs as $url => $dummy ) {
 418                         foreach( wfMakeUrlIndexes( $url ) as $index ) {
 419                                 $arr[] = array(
 420                                         'el_from'   => $this->mId,
 421                                         'el_to'     => $url,
 422                                         'el_index'  => $index,
 423                                 );
 424                         }
 425                 }
 426                 return $arr;
 427         }
 428
 429         /**
 430          * Get an array of category insertions
 431          *
 432          * @param $existing array mapping existing category names to sort keys. If both
 433          * match a link in $this, the link will be omitted from the output
 434          *
 435          * @return array
 436          */
 437         private function getCategoryInsertions( $existing = array() ) {
 438                 global $wgContLang, $wgCategoryCollation;
 439                 $diffs = array_diff_assoc( $this->mCategories, $existing );
 440                 $arr = array();
 441                 foreach ( $diffs as $name => $prefix ) {
 442                         $nt = Title::makeTitleSafe( NS_CATEGORY, $name );
 443                         $wgContLang->findVariantLink( $name, $nt, true );
 444
 445                         if ( $this->mTitle->getNamespace() == NS_CATEGORY ) {
 446                                 $type = 'subcat';
 447                         } elseif ( $this->mTitle->getNamespace() == NS_FILE ) {
 448                                 $type = 'file';
 449                         } else {
 450                                 $type = 'page';
 451                         }
 452
 453                         # Treat custom sortkeys as a prefix, so that if multiple
 454                         # things are forced to sort as '*' or something, they'll
 455                         # sort properly in the category rather than in page_id
 456                         # order or such.
 457                         $sortkey = Collation::singleton()->getSortKey(
 458                                 $this->mTitle->getCategorySortkey( $prefix ) );
 459
 460                         $arr[] = array(
 461                                 'cl_from'    => $this->mId,
 462                                 'cl_to'      => $name,
 463                                 'cl_sortkey' => $sortkey,
 464                                 'cl_timestamp' => $this->mDb->timestamp(),
 465                                 'cl_sortkey_prefix' => $prefix,
 466                                 'cl_collation' => $wgCategoryCollation,
 467                                 'cl_type' => $type,
 468                         );
 469                 }
 470                 return $arr;
 471         }
 472
 473         /**
 474          * Get an array of interlanguage link insertions
 475          *
 476          * @param $existing Array 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                 return $arr;
 491         }
 492
 493         /**
 494          * Get an array of page property insertions
 495          * @param $existing array
 496          * @return array
 497          */
 498         function getPropertyInsertions( $existing = array() ) {
 499                 $diffs = array_diff_assoc( $this->mProperties, $existing );
 500                 $arr = array();
 501                 foreach ( $diffs as $name => $value ) {
 502                         $arr[] = array(
 503                                 'pp_page'      => $this->mId,
 504                                 'pp_propname'  => $name,
 505                                 'pp_value'     => $value,
 506                         );
 507                 }
 508                 return $arr;
 509         }
 510
 511         /**
 512          * Get an array of interwiki insertions for passing to the DB
 513          * Skips the titles specified by the 2-D array $existing
 514          * @param $existing array
 515          * @return array
 516          */
 517         private function getInterwikiInsertions( $existing = array() ) {
 518                 $arr = array();
 519                 foreach( $this->mInterwikis as $prefix => $dbkeys ) {
 520                         $diffs = isset( $existing[$prefix] ) ? array_diff_key( $dbkeys, $existing[$prefix] ) : $dbkeys;
 521                         foreach ( $diffs as $dbk => $id ) {
 522                                 $arr[] = array(
 523                                         'iwl_from'   => $this->mId,
 524                                         'iwl_prefix' => $prefix,
 525                                         'iwl_title'  => $dbk
 526                                 );
 527                         }
 528                 }
 529                 return $arr;
 530         }
 531
 532         /**
 533          * Given an array of existing links, returns those links which are not in $this
 534          * and thus should be deleted.
 535          * @param $existing array
 536          * @return array
 537          */
 538         private function getLinkDeletions( $existing ) {
 539                 $del = array();
 540                 foreach ( $existing as $ns => $dbkeys ) {
 541                         if ( isset( $this->mLinks[$ns] ) ) {
 542                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mLinks[$ns] );
 543                         } else {
 544                                 $del[$ns] = $existing[$ns];
 545                         }
 546                 }
 547                 return $del;
 548         }
 549
 550         /**
 551          * Given an array of existing templates, returns those templates which are not in $this
 552          * and thus should be deleted.
 553          * @param $existing array
 554          * @return array
 555          */
 556         private function getTemplateDeletions( $existing ) {
 557                 $del = array();
 558                 foreach ( $existing as $ns => $dbkeys ) {
 559                         if ( isset( $this->mTemplates[$ns] ) ) {
 560                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mTemplates[$ns] );
 561                         } else {
 562                                 $del[$ns] = $existing[$ns];
 563                         }
 564                 }
 565                 return $del;
 566         }
 567
 568         /**
 569          * Given an array of existing images, returns those images which are not in $this
 570          * and thus should be deleted.
 571          * @param $existing array
 572          * @return array
 573          */
 574         private function getImageDeletions( $existing ) {
 575                 return array_diff_key( $existing, $this->mImages );
 576         }
 577
 578         /**
 579          * Given an array of existing external links, returns those links which are not
 580          * in $this and thus should be deleted.
 581          * @param $existing array
 582          * @return array
 583          */
 584         private function getExternalDeletions( $existing ) {
 585                 return array_diff_key( $existing, $this->mExternals );
 586         }
 587
 588         /**
 589          * Given an array of existing categories, returns those categories which are not in $this
 590          * and thus should be deleted.
 591          * @param $existing array
 592          * @return array
 593          */
 594         private function getCategoryDeletions( $existing ) {
 595                 return array_diff_assoc( $existing, $this->mCategories );
 596         }
 597
 598         /**
 599          * Given an array of existing interlanguage links, returns those links which are not
 600          * in $this and thus should be deleted.
 601          * @param $existing array
 602          * @return array
 603          */
 604         private function getInterlangDeletions( $existing ) {
 605                 return array_diff_assoc( $existing, $this->mInterlangs );
 606         }
 607
 608         /**
 609          * Get array of properties which should be deleted.
 610          * @param $existing array
 611          * @return array
 612          */
 613         function getPropertyDeletions( $existing ) {
 614                 return array_diff_assoc( $existing, $this->mProperties );
 615         }
 616
 617         /**
 618          * Given an array of existing interwiki links, returns those links which are not in $this
 619          * and thus should be deleted.
 620          * @param $existing array
 621          * @return array
 622          */
 623         private function getInterwikiDeletions( $existing ) {
 624                 $del = array();
 625                 foreach ( $existing as $prefix => $dbkeys ) {
 626                         if ( isset( $this->mInterwikis[$prefix] ) ) {
 627                                 $del[$prefix] = array_diff_key( $existing[$prefix], $this->mInterwikis[$prefix] );
 628                         } else {
 629                                 $del[$prefix] = $existing[$prefix];
 630                         }
 631                 }
 632                 return $del;
 633         }
 634
 635         /**
 636          * Get an array of existing links, as a 2-D array
 637          *
 638          * @return array
 639          */
 640         private function getExistingLinks() {
 641                 $res = $this->mDb->select( 'pagelinks', array( 'pl_namespace', 'pl_title' ),
 642                         array( 'pl_from' => $this->mId ), __METHOD__, $this->mOptions );
 643                 $arr = array();
 644                 foreach ( $res as $row ) {
 645                         if ( !isset( $arr[$row->pl_namespace] ) ) {
 646                                 $arr[$row->pl_namespace] = array();
 647                         }
 648                         $arr[$row->pl_namespace][$row->pl_title] = 1;
 649                 }
 650                 return $arr;
 651         }
 652
 653         /**
 654          * Get an array of existing templates, as a 2-D array
 655          *
 656          * @return array
 657          */
 658         private function getExistingTemplates() {
 659                 $res = $this->mDb->select( 'templatelinks', array( 'tl_namespace', 'tl_title' ),
 660                         array( 'tl_from' => $this->mId ), __METHOD__, $this->mOptions );
 661                 $arr = array();
 662                 foreach ( $res as $row ) {
 663                         if ( !isset( $arr[$row->tl_namespace] ) ) {
 664                                 $arr[$row->tl_namespace] = array();
 665                         }
 666                         $arr[$row->tl_namespace][$row->tl_title] = 1;
 667                 }
 668                 return $arr;
 669         }
 670
 671         /**
 672          * Get an array of existing images, image names in the keys
 673          *
 674          * @return array
 675          */
 676         private function getExistingImages() {
 677                 $res = $this->mDb->select( 'imagelinks', array( 'il_to' ),
 678                         array( 'il_from' => $this->mId ), __METHOD__, $this->mOptions );
 679                 $arr = array();
 680                 foreach ( $res as $row ) {
 681                         $arr[$row->il_to] = 1;
 682                 }
 683                 return $arr;
 684         }
 685
 686         /**
 687          * Get an array of existing external links, URLs in the keys
 688          *
 689          * @return array
 690          */
 691         private function getExistingExternals() {
 692                 $res = $this->mDb->select( 'externallinks', array( 'el_to' ),
 693                         array( 'el_from' => $this->mId ), __METHOD__, $this->mOptions );
 694                 $arr = array();
 695                 foreach ( $res as $row ) {
 696                         $arr[$row->el_to] = 1;
 697                 }
 698                 return $arr;
 699         }
 700
 701         /**
 702          * Get an array of existing categories, with the name in the key and sort key in the value.
 703          *
 704          * @return array
 705          */
 706         private function getExistingCategories() {
 707                 $res = $this->mDb->select( 'categorylinks', array( 'cl_to', 'cl_sortkey_prefix' ),
 708                         array( 'cl_from' => $this->mId ), __METHOD__, $this->mOptions );
 709                 $arr = array();
 710                 foreach ( $res as $row ) {
 711                         $arr[$row->cl_to] = $row->cl_sortkey_prefix;
 712                 }
 713                 return $arr;
 714         }
 715
 716         /**
 717          * Get an array of existing interlanguage links, with the language code in the key and the
 718          * title in the value.
 719          *
 720          * @return array
 721          */
 722         private function getExistingInterlangs() {
 723                 $res = $this->mDb->select( 'langlinks', array( 'll_lang', 'll_title' ),
 724                         array( 'll_from' => $this->mId ), __METHOD__, $this->mOptions );
 725                 $arr = array();
 726                 foreach ( $res as $row ) {
 727                         $arr[$row->ll_lang] = $row->ll_title;
 728                 }
 729                 return $arr;
 730         }
 731
 732         /**
 733          * Get an array of existing inline interwiki links, as a 2-D array
 734          * @return array (prefix => array(dbkey => 1))
 735          */
 736         protected function getExistingInterwikis() {
 737                 $res = $this->mDb->select( 'iwlinks', array( 'iwl_prefix', 'iwl_title' ),
 738                         array( 'iwl_from' => $this->mId ), __METHOD__, $this->mOptions );
 739                 $arr = array();
 740                 foreach ( $res as $row ) {
 741                         if ( !isset( $arr[$row->iwl_prefix] ) ) {
 742                                 $arr[$row->iwl_prefix] = array();
 743                         }
 744                         $arr[$row->iwl_prefix][$row->iwl_title] = 1;
 745                 }
 746                 return $arr;
 747         }
 748
 749         /**
 750          * Get an array of existing categories, with the name in the key and sort key in the value.
 751          *
 752          * @return array
 753          */
 754         private function getExistingProperties() {
 755                 $res = $this->mDb->select( 'page_props', array( 'pp_propname', 'pp_value' ),
 756                         array( 'pp_page' => $this->mId ), __METHOD__, $this->mOptions );
 757                 $arr = array();
 758                 foreach ( $res as $row ) {
 759                         $arr[$row->pp_propname] = $row->pp_value;
 760                 }
 761                 return $arr;
 762         }
 763
 764         /**
 765          * Return the title object of the page being updated
 766          * @return Title
 767          */
 768         public function getTitle() {
 769                 return $this->mTitle;
 770         }
 771
 772         /**
 773          * Returns parser output
 774          * @since 1.19
 775          * @return ParserOutput
 776          */
 777         public function getParserOutput() {
 778                 return $this->mParserOutput;
 779         }
 780
 781         /**
 782          * Return the list of images used as generated by the parser
 783          * @return array
 784          */
 785         public function getImages() {
 786                 return $this->mImages;
 787         }
 788
 789         /**
 790          * Invalidate any necessary link lists related to page property changes
 791          * @param $changed
 792          */
 793         private function invalidateProperties( $changed ) {
 794                 global $wgPagePropLinkInvalidations;
 795
 796                 foreach ( $changed as $name => $value ) {
 797                         if ( isset( $wgPagePropLinkInvalidations[$name] ) ) {
 798                                 $inv = $wgPagePropLinkInvalidations[$name];
 799                                 if ( !is_array( $inv ) ) {
 800                                         $inv = array( $inv );
 801                                 }
 802                                 foreach ( $inv as $table ) {
 803                                         $update = new HTMLCacheUpdate( $this->mTitle, $table );
 804                                         $update->doUpdate();
 805                                 }
 806                         }
 807                 }
 808         }
 809 }
 810
 811 /**
 812  * Update object handling the cleanup of links tables after a page was deleted.
 813  **/
 814 class LinksDeletionUpdate extends SqlDataUpdate {
 815
 816         protected $mPage;     //!< WikiPage the wikipage that was deleted
 817
 818         /**
 819          * Constructor
 820          *
 821          * @param $title Title of the page we're updating
 822          * @param $parserOutput ParserOutput: output from a full parse of this page
 823          * @param $recursive Boolean: queue jobs for recursive updates?
 824          */
 825         function __construct( WikiPage $page ) {
 826                 parent::__construct( );
 827
 828                 $this->mPage = $page;
 829         }
 830
 831         /**
 832          * Do some database updates after deletion
 833          */
 834         public function doUpdate() {
 835                 $title = $this->mPage->getTitle();
 836                 $id = $this->mPage->getId();
 837
 838                 # Delete restrictions for it
 839                 $this->mDb->delete( 'page_restrictions', array ( 'pr_page' => $id ), __METHOD__ );
 840
 841                 # Fix category table counts
 842                 $cats = array();
 843                 $res = $this->mDb->select( 'categorylinks', 'cl_to', array( 'cl_from' => $id ), __METHOD__ );
 844
 845                 foreach ( $res as $row ) {
 846                         $cats [] = $row->cl_to;
 847                 }
 848
 849                 $this->mPage->updateCategoryCounts( array(), $cats );
 850
 851                 # If using cascading deletes, we can skip some explicit deletes
 852                 if ( !$this->mDb->cascadingDeletes() ) {
 853                         $this->mDb->delete( 'revision', array( 'rev_page' => $id ), __METHOD__ );
 854
 855                         # Delete outgoing links
 856                         $this->mDb->delete( 'pagelinks', array( 'pl_from' => $id ), __METHOD__ );
 857                         $this->mDb->delete( 'imagelinks', array( 'il_from' => $id ), __METHOD__ );
 858                         $this->mDb->delete( 'categorylinks', array( 'cl_from' => $id ), __METHOD__ );
 859                         $this->mDb->delete( 'templatelinks', array( 'tl_from' => $id ), __METHOD__ );
 860                         $this->mDb->delete( 'externallinks', array( 'el_from' => $id ), __METHOD__ );
 861                         $this->mDb->delete( 'langlinks', array( 'll_from' => $id ), __METHOD__ );
 862                         $this->mDb->delete( 'iwlinks', array( 'iwl_from' => $id ), __METHOD__ );
 863                         $this->mDb->delete( 'redirect', array( 'rd_from' => $id ), __METHOD__ );
 864                         $this->mDb->delete( 'page_props', array( 'pp_page' => $id ), __METHOD__ );
 865                 }
 866
 867                 # If using cleanup triggers, we can skip some manual deletes
 868                 if ( !$this->mDb->cleanupTriggers() ) {
 869                         # Clean up recentchanges entries...
 870                         $this->mDb->delete( 'recentchanges',
 871                                 array( 'rc_type != ' . RC_LOG,
 872                                         'rc_namespace' => $title->getNamespace(),
 873                                         'rc_title' => $title->getDBkey() ),
 874                                 __METHOD__ );
 875                         $this->mDb->delete( 'recentchanges',
 876                                 array( 'rc_type != ' . RC_LOG, 'rc_cur_id' => $id ),
 877                                 __METHOD__ );
 878                 }
 879         }
 880 }