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 {
  29
  30         /**@{{
  31          * @private
  32          */
  33         var $mId,            //!< Page ID of the article linked from
  34                 $mTitle,         //!< Title object of the article linked from
  35                 $mParserOutput,  //!< Parser output
  36                 $mLinks,         //!< Map of title strings to IDs for the links in the document
  37                 $mImages,        //!< DB keys of the images used, in the array key only
  38                 $mTemplates,     //!< Map of title strings to IDs for the template references, including broken ones
  39                 $mExternals,     //!< URLs of external links, array key only
  40                 $mCategories,    //!< Map of category names to sort keys
  41                 $mInterlangs,    //!< Map of language codes to titles
  42                 $mProperties,    //!< Map of arbitrary name to value
  43                 $mDb,            //!< Database connection reference
  44                 $mOptions,       //!< SELECT options to be used (array)
  45                 $mRecursive;     //!< Whether to queue jobs for recursive updates
  46         /**@}}*/
  47
  48         /**
  49          * Constructor
  50          *
  51          * @param $title Title of the page we're updating
  52          * @param $parserOutput ParserOutput: output from a full parse of this page
  53          * @param $recursive Boolean: queue jobs for recursive updates?
  54          */
  55         function __construct( $title, $parserOutput, $recursive = true ) {
  56                 global $wgAntiLockFlags;
  57
  58                 if ( $wgAntiLockFlags & ALF_NO_LINK_LOCK ) {
  59                         $this->mOptions = array();
  60                 } else {
  61                         $this->mOptions = array( 'FOR UPDATE' );
  62                 }
  63                 $this->mDb = wfGetDB( DB_MASTER );
  64
  65                 if ( !is_object( $title ) ) {
  66                         throw new MWException( "The calling convention to LinksUpdate::__construct() has changed. " .
  67                                 "Please see WikiPage::doEditUpdates() for an invocation example.\n" );
  68                 }
  69                 $this->mTitle = $title;
  70                 $this->mId = $title->getArticleID();
  71
  72                 $this->mParserOutput = $parserOutput;
  73                 $this->mLinks = $parserOutput->getLinks();
  74                 $this->mImages = $parserOutput->getImages();
  75                 $this->mTemplates = $parserOutput->getTemplates();
  76                 $this->mExternals = $parserOutput->getExternalLinks();
  77                 $this->mCategories = $parserOutput->getCategories();
  78                 $this->mProperties = $parserOutput->getProperties();
  79                 $this->mInterwikis = $parserOutput->getInterwikiLinks();
  80
  81                 # Convert the format of the interlanguage links
  82                 # I didn't want to change it in the ParserOutput, because that array is passed all
  83                 # the way back to the skin, so either a skin API break would be required, or an
  84                 # inefficient back-conversion.
  85                 $ill = $parserOutput->getLanguageLinks();
  86                 $this->mInterlangs = array();
  87                 foreach ( $ill as $link ) {
  88                         list( $key, $title ) = explode( ':', $link, 2 );
  89                         $this->mInterlangs[$key] = $title;
  90                 }
  91
  92                 foreach ( $this->mCategories as &$sortkey ) {
  93                         # If the sortkey is longer then 255 bytes,
  94                         # it truncated by DB, and then doesn't get
  95                         # matched when comparing existing vs current
  96                         # categories, causing bug 25254.
  97                         # Also. substr behaves weird when given "".
  98                         if ( $sortkey !== '' ) {
  99                                 $sortkey = substr( $sortkey, 0, 255 );
 100                         }
 101                 }
 102
 103                 $this->mRecursive = $recursive;
 104
 105                 wfRunHooks( 'LinksUpdateConstructed', array( &$this ) );
 106         }
 107
 108         /**
 109          * Update link tables with outgoing links from an updated article
 110          */
 111         public function doUpdate() {
 112                 global $wgUseDumbLinkUpdate;
 113
 114                 wfRunHooks( 'LinksUpdate', array( &$this ) );
 115                 if ( $wgUseDumbLinkUpdate ) {
 116                         $this->doDumbUpdate();
 117                 } else {
 118                         $this->doIncrementalUpdate();
 119                 }
 120                 wfRunHooks( 'LinksUpdateComplete', array( &$this ) );
 121         }
 122
 123         protected function doIncrementalUpdate() {
 124                 wfProfileIn( __METHOD__ );
 125
 126                 # Page links
 127                 $existing = $this->getExistingLinks();
 128                 $this->incrTableUpdate( 'pagelinks', 'pl', $this->getLinkDeletions( $existing ),
 129                         $this->getLinkInsertions( $existing ) );
 130
 131                 # Image links
 132                 $existing = $this->getExistingImages();
 133
 134                 $imageDeletes = $this->getImageDeletions( $existing );
 135                 $this->incrTableUpdate( 'imagelinks', 'il', $imageDeletes,
 136                         $this->getImageInsertions( $existing ) );
 137
 138                 # Invalidate all image description pages which had links added or removed
 139                 $imageUpdates = $imageDeletes + array_diff_key( $this->mImages, $existing );
 140                 $this->invalidateImageDescriptions( $imageUpdates );
 141
 142                 # External links
 143                 $existing = $this->getExistingExternals();
 144                 $this->incrTableUpdate( 'externallinks', 'el', $this->getExternalDeletions( $existing ),
 145                         $this->getExternalInsertions( $existing ) );
 146
 147                 # Language links
 148                 $existing = $this->getExistingInterlangs();
 149                 $this->incrTableUpdate( 'langlinks', 'll', $this->getInterlangDeletions( $existing ),
 150                         $this->getInterlangInsertions( $existing ) );
 151
 152                 # Inline interwiki links
 153                 $existing = $this->getExistingInterwikis();
 154                 $this->incrTableUpdate( 'iwlinks', 'iwl', $this->getInterwikiDeletions( $existing ),
 155                         $this->getInterwikiInsertions( $existing ) );
 156
 157                 # Template links
 158                 $existing = $this->getExistingTemplates();
 159                 $this->incrTableUpdate( 'templatelinks', 'tl', $this->getTemplateDeletions( $existing ),
 160                         $this->getTemplateInsertions( $existing ) );
 161
 162                 # Category links
 163                 $existing = $this->getExistingCategories();
 164
 165                 $categoryDeletes = $this->getCategoryDeletions( $existing );
 166
 167                 $this->incrTableUpdate( 'categorylinks', 'cl', $categoryDeletes,
 168                         $this->getCategoryInsertions( $existing ) );
 169
 170                 # Invalidate all categories which were added, deleted or changed (set symmetric difference)
 171                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 172                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 173                 $this->invalidateCategories( $categoryUpdates );
 174                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 175
 176                 # Page properties
 177                 $existing = $this->getExistingProperties();
 178
 179                 $propertiesDeletes = $this->getPropertyDeletions( $existing );
 180
 181                 $this->incrTableUpdate( 'page_props', 'pp', $propertiesDeletes,
 182                         $this->getPropertyInsertions( $existing ) );
 183
 184                 # Invalidate the necessary pages
 185                 $changed = $propertiesDeletes + array_diff_assoc( $this->mProperties, $existing );
 186                 $this->invalidateProperties( $changed );
 187
 188                 # Refresh links of all pages including this page
 189                 # This will be in a separate transaction
 190                 if ( $this->mRecursive ) {
 191                         $this->queueRecursiveJobs();
 192                 }
 193
 194                 wfProfileOut( __METHOD__ );
 195         }
 196
 197         /**
 198          * Link update which clears the previous entries and inserts new ones
 199          * May be slower or faster depending on level of lock contention and write speed of DB
 200          * Also useful where link table corruption needs to be repaired, e.g. in refreshLinks.php
 201          */
 202         protected function doDumbUpdate() {
 203                 wfProfileIn( __METHOD__ );
 204
 205                 # Refresh category pages and image description pages
 206                 $existing = $this->getExistingCategories();
 207                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 208                 $categoryDeletes = array_diff_assoc( $existing, $this->mCategories );
 209                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 210                 $existing = $this->getExistingImages();
 211                 $imageUpdates = array_diff_key( $existing, $this->mImages ) + array_diff_key( $this->mImages, $existing );
 212
 213                 $this->dumbTableUpdate( 'pagelinks',     $this->getLinkInsertions(),     'pl_from' );
 214                 $this->dumbTableUpdate( 'imagelinks',    $this->getImageInsertions(),    'il_from' );
 215                 $this->dumbTableUpdate( 'categorylinks', $this->getCategoryInsertions(), 'cl_from' );
 216                 $this->dumbTableUpdate( 'templatelinks', $this->getTemplateInsertions(), 'tl_from' );
 217                 $this->dumbTableUpdate( 'externallinks', $this->getExternalInsertions(), 'el_from' );
 218                 $this->dumbTableUpdate( 'langlinks',     $this->getInterlangInsertions(),'ll_from' );
 219                 $this->dumbTableUpdate( 'iwlinks',       $this->getInterwikiInsertions(),'iwl_from' );
 220                 $this->dumbTableUpdate( 'page_props',    $this->getPropertyInsertions(), 'pp_page' );
 221
 222                 # Update the cache of all the category pages and image description
 223                 # pages which were changed, and fix the category table count
 224                 $this->invalidateCategories( $categoryUpdates );
 225                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 226                 $this->invalidateImageDescriptions( $imageUpdates );
 227
 228                 # Refresh links of all pages including this page
 229                 # This will be in a separate transaction
 230                 if ( $this->mRecursive ) {
 231                         $this->queueRecursiveJobs();
 232                 }
 233
 234                 wfProfileOut( __METHOD__ );
 235         }
 236
 237         function queueRecursiveJobs() {
 238                 global $wgUpdateRowsPerJob;
 239                 wfProfileIn( __METHOD__ );
 240
 241                 $cache = $this->mTitle->getBacklinkCache();
 242                 $batches = $cache->partition( 'templatelinks', $wgUpdateRowsPerJob );
 243                 if ( !$batches ) {
 244                         wfProfileOut( __METHOD__ );
 245                         return;
 246                 }
 247                 $jobs = array();
 248                 foreach ( $batches as $batch ) {
 249                         list( $start, $end ) = $batch;
 250                         $params = array(
 251                                 'table' => 'templatelinks',
 252                                 'start' => $start,
 253                                 'end' => $end,
 254                         );
 255                         $jobs[] = new RefreshLinksJob2( $this->mTitle, $params );
 256                 }
 257                 Job::batchInsert( $jobs );
 258
 259                 wfProfileOut( __METHOD__ );
 260         }
 261
 262         /**
 263          * Invalidate the cache of a list of pages from a single namespace
 264          *
 265          * @param $namespace Integer
 266          * @param $dbkeys Array
 267          */
 268         function invalidatePages( $namespace, $dbkeys ) {
 269                 if ( !count( $dbkeys ) ) {
 270                         return;
 271                 }
 272
 273                 /**
 274                  * Determine which pages need to be updated
 275                  * This is necessary to prevent the job queue from smashing the DB with
 276                  * large numbers of concurrent invalidations of the same page
 277                  */
 278                 $now = $this->mDb->timestamp();
 279                 $ids = array();
 280                 $res = $this->mDb->select( 'page', array( 'page_id' ),
 281                         array(
 282                                 'page_namespace' => $namespace,
 283                                 'page_title IN (' . $this->mDb->makeList( $dbkeys ) . ')',
 284                                 'page_touched < ' . $this->mDb->addQuotes( $now )
 285                         ), __METHOD__
 286                 );
 287                 foreach ( $res as $row ) {
 288                         $ids[] = $row->page_id;
 289                 }
 290                 if ( !count( $ids ) ) {
 291                         return;
 292                 }
 293
 294                 /**
 295                  * Do the update
 296                  * We still need the page_touched condition, in case the row has changed since
 297                  * the non-locking select above.
 298                  */
 299                 $this->mDb->update( 'page', array( 'page_touched' => $now ),
 300                         array(
 301                                 'page_id IN (' . $this->mDb->makeList( $ids ) . ')',
 302                                 'page_touched < ' . $this->mDb->addQuotes( $now )
 303                         ), __METHOD__
 304                 );
 305         }
 306
 307         /**
 308          * @param $cats
 309          */
 310         function invalidateCategories( $cats ) {
 311                 $this->invalidatePages( NS_CATEGORY, array_keys( $cats ) );
 312         }
 313
 314         /**
 315          * Update all the appropriate counts in the category table.
 316          * @param $added array associative array of category name => sort key
 317          * @param $deleted array associative array of category name => sort key
 318          */
 319         function updateCategoryCounts( $added, $deleted ) {
 320                 $a = WikiPage::factory( $this->mTitle );
 321                 $a->updateCategoryCounts(
 322                         array_keys( $added ), array_keys( $deleted )
 323                 );
 324         }
 325
 326         /**
 327          * @param $images
 328          */
 329         function invalidateImageDescriptions( $images ) {
 330                 $this->invalidatePages( NS_FILE, array_keys( $images ) );
 331         }
 332
 333         /**
 334          * @param $table
 335          * @param $insertions
 336          * @param $fromField
 337          */
 338         private function dumbTableUpdate( $table, $insertions, $fromField ) {
 339                 $this->mDb->delete( $table, array( $fromField => $this->mId ), __METHOD__ );
 340                 if ( count( $insertions ) ) {
 341                         # The link array was constructed without FOR UPDATE, so there may
 342                         # be collisions.  This may cause minor link table inconsistencies,
 343                         # which is better than crippling the site with lock contention.
 344                         $this->mDb->insert( $table, $insertions, __METHOD__, array( 'IGNORE' ) );
 345                 }
 346         }
 347
 348         /**
 349          * Update a table by doing a delete query then an insert query
 350          * @param $table
 351          * @param $prefix
 352          * @param $deletions
 353          * @param $insertions
 354          */
 355         function incrTableUpdate( $table, $prefix, $deletions, $insertions ) {
 356                 if ( $table == 'page_props' ) {
 357                         $fromField = 'pp_page';
 358                 } else {
 359                         $fromField = "{$prefix}_from";
 360                 }
 361                 $where = array( $fromField => $this->mId );
 362                 if ( $table == 'pagelinks' || $table == 'templatelinks' || $table == 'iwlinks' ) {
 363                         if ( $table == 'iwlinks' ) {
 364                                 $baseKey = 'iwl_prefix';
 365                         } else {
 366                                 $baseKey = "{$prefix}_namespace";
 367                         }
 368                         $clause = $this->mDb->makeWhereFrom2d( $deletions, $baseKey, "{$prefix}_title" );
 369                         if ( $clause ) {
 370                                 $where[] = $clause;
 371                         } else {
 372                                 $where = false;
 373                         }
 374                 } else {
 375                         if ( $table == 'langlinks' ) {
 376                                 $toField = 'll_lang';
 377                         } elseif ( $table == 'page_props' ) {
 378                                 $toField = 'pp_propname';
 379                         } else {
 380                                 $toField = $prefix . '_to';
 381                         }
 382                         if ( count( $deletions ) ) {
 383                                 $where[] = "$toField IN (" . $this->mDb->makeList( array_keys( $deletions ) ) . ')';
 384                         } else {
 385                                 $where = false;
 386                         }
 387                 }
 388                 if ( $where ) {
 389                         $this->mDb->delete( $table, $where, __METHOD__ );
 390                 }
 391                 if ( count( $insertions ) ) {
 392                         $this->mDb->insert( $table, $insertions, __METHOD__, 'IGNORE' );
 393                 }
 394         }
 395
 396         /**
 397          * Get an array of pagelinks insertions for passing to the DB
 398          * Skips the titles specified by the 2-D array $existing
 399          * @param $existing array
 400          * @return array
 401          */
 402         private function getLinkInsertions( $existing = array() ) {
 403                 $arr = array();
 404                 foreach( $this->mLinks as $ns => $dbkeys ) {
 405                         $diffs = isset( $existing[$ns] )
 406                                 ? array_diff_key( $dbkeys, $existing[$ns] )
 407                                 : $dbkeys;
 408                         foreach ( $diffs as $dbk => $id ) {
 409                                 $arr[] = array(
 410                                         'pl_from'      => $this->mId,
 411                                         'pl_namespace' => $ns,
 412                                         'pl_title'     => $dbk
 413                                 );
 414                         }
 415                 }
 416                 return $arr;
 417         }
 418
 419         /**
 420          * Get an array of template insertions. Like getLinkInsertions()
 421          * @param $existing array
 422          * @return array
 423          */
 424         private function getTemplateInsertions( $existing = array() ) {
 425                 $arr = array();
 426                 foreach( $this->mTemplates as $ns => $dbkeys ) {
 427                         $diffs = isset( $existing[$ns] ) ? array_diff_key( $dbkeys, $existing[$ns] ) : $dbkeys;
 428                         foreach ( $diffs as $dbk => $id ) {
 429                                 $arr[] = array(
 430                                         'tl_from'      => $this->mId,
 431                                         'tl_namespace' => $ns,
 432                                         'tl_title'     => $dbk
 433                                 );
 434                         }
 435                 }
 436                 return $arr;
 437         }
 438
 439         /**
 440          * Get an array of image insertions
 441          * Skips the names specified in $existing
 442          * @param $existing array
 443          * @return array
 444          */
 445         private function getImageInsertions( $existing = array() ) {
 446                 $arr = array();
 447                 $diffs = array_diff_key( $this->mImages, $existing );
 448                 foreach( $diffs as $iname => $dummy ) {
 449                         $arr[] = array(
 450                                 'il_from' => $this->mId,
 451                                 'il_to'   => $iname
 452                         );
 453                 }
 454                 return $arr;
 455         }
 456
 457         /**
 458          * Get an array of externallinks insertions. Skips the names specified in $existing
 459          * @param $existing array
 460          * @return array
 461          */
 462         private function getExternalInsertions( $existing = array() ) {
 463                 $arr = array();
 464                 $diffs = array_diff_key( $this->mExternals, $existing );
 465                 foreach( $diffs as $url => $dummy ) {
 466                         foreach( wfMakeUrlIndexes( $url ) as $index ) {
 467                                 $arr[] = array(
 468                                         'el_from'   => $this->mId,
 469                                         'el_to'     => $url,
 470                                         'el_index'  => $index,
 471                                 );
 472                         }
 473                 }
 474                 return $arr;
 475         }
 476
 477         /**
 478          * Get an array of category insertions
 479          *
 480          * @param $existing array mapping existing category names to sort keys. If both
 481          * match a link in $this, the link will be omitted from the output
 482          *
 483          * @return array
 484          */
 485         private function getCategoryInsertions( $existing = array() ) {
 486                 global $wgContLang, $wgCategoryCollation;
 487                 $diffs = array_diff_assoc( $this->mCategories, $existing );
 488                 $arr = array();
 489                 foreach ( $diffs as $name => $prefix ) {
 490                         $nt = Title::makeTitleSafe( NS_CATEGORY, $name );
 491                         $wgContLang->findVariantLink( $name, $nt, true );
 492
 493                         if ( $this->mTitle->getNamespace() == NS_CATEGORY ) {
 494                                 $type = 'subcat';
 495                         } elseif ( $this->mTitle->getNamespace() == NS_FILE ) {
 496                                 $type = 'file';
 497                         } else {
 498                                 $type = 'page';
 499                         }
 500
 501                         # Treat custom sortkeys as a prefix, so that if multiple
 502                         # things are forced to sort as '*' or something, they'll
 503                         # sort properly in the category rather than in page_id
 504                         # order or such.
 505                         $sortkey = Collation::singleton()->getSortKey(
 506                                 $this->mTitle->getCategorySortkey( $prefix ) );
 507
 508                         $arr[] = array(
 509                                 'cl_from'    => $this->mId,
 510                                 'cl_to'      => $name,
 511                                 'cl_sortkey' => $sortkey,
 512                                 'cl_timestamp' => $this->mDb->timestamp(),
 513                                 'cl_sortkey_prefix' => $prefix,
 514                                 'cl_collation' => $wgCategoryCollation,
 515                                 'cl_type' => $type,
 516                         );
 517                 }
 518                 return $arr;
 519         }
 520
 521         /**
 522          * Get an array of interlanguage link insertions
 523          *
 524          * @param $existing Array mapping existing language codes to titles
 525          *
 526          * @return array
 527          */
 528         private function getInterlangInsertions( $existing = array() ) {
 529                 $diffs = array_diff_assoc( $this->mInterlangs, $existing );
 530                 $arr = array();
 531                 foreach( $diffs as $lang => $title ) {
 532                         $arr[] = array(
 533                                 'll_from'  => $this->mId,
 534                                 'll_lang'  => $lang,
 535                                 'll_title' => $title
 536                         );
 537                 }
 538                 return $arr;
 539         }
 540
 541         /**
 542          * Get an array of page property insertions
 543          * @param $existing array
 544          * @return array
 545          */
 546         function getPropertyInsertions( $existing = array() ) {
 547                 $diffs = array_diff_assoc( $this->mProperties, $existing );
 548                 $arr = array();
 549                 foreach ( $diffs as $name => $value ) {
 550                         $arr[] = array(
 551                                 'pp_page'      => $this->mId,
 552                                 'pp_propname'  => $name,
 553                                 'pp_value'     => $value,
 554                         );
 555                 }
 556                 return $arr;
 557         }
 558
 559         /**
 560          * Get an array of interwiki insertions for passing to the DB
 561          * Skips the titles specified by the 2-D array $existing
 562          * @param $existing array
 563          * @return array
 564          */
 565         private function getInterwikiInsertions( $existing = array() ) {
 566                 $arr = array();
 567                 foreach( $this->mInterwikis as $prefix => $dbkeys ) {
 568                         $diffs = isset( $existing[$prefix] ) ? array_diff_key( $dbkeys, $existing[$prefix] ) : $dbkeys;
 569                         foreach ( $diffs as $dbk => $id ) {
 570                                 $arr[] = array(
 571                                         'iwl_from'   => $this->mId,
 572                                         'iwl_prefix' => $prefix,
 573                                         'iwl_title'  => $dbk
 574                                 );
 575                         }
 576                 }
 577                 return $arr;
 578         }
 579
 580         /**
 581          * Given an array of existing links, returns those links which are not in $this
 582          * and thus should be deleted.
 583          * @param $existing array
 584          * @return array
 585          */
 586         private function getLinkDeletions( $existing ) {
 587                 $del = array();
 588                 foreach ( $existing as $ns => $dbkeys ) {
 589                         if ( isset( $this->mLinks[$ns] ) ) {
 590                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mLinks[$ns] );
 591                         } else {
 592                                 $del[$ns] = $existing[$ns];
 593                         }
 594                 }
 595                 return $del;
 596         }
 597
 598         /**
 599          * Given an array of existing templates, returns those templates which are not in $this
 600          * and thus should be deleted.
 601          * @param $existing array
 602          * @return array
 603          */
 604         private function getTemplateDeletions( $existing ) {
 605                 $del = array();
 606                 foreach ( $existing as $ns => $dbkeys ) {
 607                         if ( isset( $this->mTemplates[$ns] ) ) {
 608                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mTemplates[$ns] );
 609                         } else {
 610                                 $del[$ns] = $existing[$ns];
 611                         }
 612                 }
 613                 return $del;
 614         }
 615
 616         /**
 617          * Given an array of existing images, returns those images which are not in $this
 618          * and thus should be deleted.
 619          * @param $existing array
 620          * @return array
 621          */
 622         private function getImageDeletions( $existing ) {
 623                 return array_diff_key( $existing, $this->mImages );
 624         }
 625
 626         /**
 627          * Given an array of existing external links, returns those links which are not
 628          * in $this and thus should be deleted.
 629          * @param $existing array
 630          * @return array
 631          */
 632         private function getExternalDeletions( $existing ) {
 633                 return array_diff_key( $existing, $this->mExternals );
 634         }
 635
 636         /**
 637          * Given an array of existing categories, returns those categories which are not in $this
 638          * and thus should be deleted.
 639          * @param $existing array
 640          * @return array
 641          */
 642         private function getCategoryDeletions( $existing ) {
 643                 return array_diff_assoc( $existing, $this->mCategories );
 644         }
 645
 646         /**
 647          * Given an array of existing interlanguage links, returns those links which are not
 648          * in $this and thus should be deleted.
 649          * @param $existing array
 650          * @return array
 651          */
 652         private function getInterlangDeletions( $existing ) {
 653                 return array_diff_assoc( $existing, $this->mInterlangs );
 654         }
 655
 656         /**
 657          * Get array of properties which should be deleted.
 658          * @param $existing array
 659          * @return array
 660          */
 661         function getPropertyDeletions( $existing ) {
 662                 return array_diff_assoc( $existing, $this->mProperties );
 663         }
 664
 665         /**
 666          * Given an array of existing interwiki links, returns those links which are not in $this
 667          * and thus should be deleted.
 668          * @param $existing array
 669          * @return array
 670          */
 671         private function getInterwikiDeletions( $existing ) {
 672                 $del = array();
 673                 foreach ( $existing as $prefix => $dbkeys ) {
 674                         if ( isset( $this->mInterwikis[$prefix] ) ) {
 675                                 $del[$prefix] = array_diff_key( $existing[$prefix], $this->mInterwikis[$prefix] );
 676                         } else {
 677                                 $del[$prefix] = $existing[$prefix];
 678                         }
 679                 }
 680                 return $del;
 681         }
 682
 683         /**
 684          * Get an array of existing links, as a 2-D array
 685          *
 686          * @return array
 687          */
 688         private function getExistingLinks() {
 689                 $res = $this->mDb->select( 'pagelinks', array( 'pl_namespace', 'pl_title' ),
 690                         array( 'pl_from' => $this->mId ), __METHOD__, $this->mOptions );
 691                 $arr = array();
 692                 foreach ( $res as $row ) {
 693                         if ( !isset( $arr[$row->pl_namespace] ) ) {
 694                                 $arr[$row->pl_namespace] = array();
 695                         }
 696                         $arr[$row->pl_namespace][$row->pl_title] = 1;
 697                 }
 698                 return $arr;
 699         }
 700
 701         /**
 702          * Get an array of existing templates, as a 2-D array
 703          *
 704          * @return array
 705          */
 706         private function getExistingTemplates() {
 707                 $res = $this->mDb->select( 'templatelinks', array( 'tl_namespace', 'tl_title' ),
 708                         array( 'tl_from' => $this->mId ), __METHOD__, $this->mOptions );
 709                 $arr = array();
 710                 foreach ( $res as $row ) {
 711                         if ( !isset( $arr[$row->tl_namespace] ) ) {
 712                                 $arr[$row->tl_namespace] = array();
 713                         }
 714                         $arr[$row->tl_namespace][$row->tl_title] = 1;
 715                 }
 716                 return $arr;
 717         }
 718
 719         /**
 720          * Get an array of existing images, image names in the keys
 721          *
 722          * @return array
 723          */
 724         private function getExistingImages() {
 725                 $res = $this->mDb->select( 'imagelinks', array( 'il_to' ),
 726                         array( 'il_from' => $this->mId ), __METHOD__, $this->mOptions );
 727                 $arr = array();
 728                 foreach ( $res as $row ) {
 729                         $arr[$row->il_to] = 1;
 730                 }
 731                 return $arr;
 732         }
 733
 734         /**
 735          * Get an array of existing external links, URLs in the keys
 736          *
 737          * @return array
 738          */
 739         private function getExistingExternals() {
 740                 $res = $this->mDb->select( 'externallinks', array( 'el_to' ),
 741                         array( 'el_from' => $this->mId ), __METHOD__, $this->mOptions );
 742                 $arr = array();
 743                 foreach ( $res as $row ) {
 744                         $arr[$row->el_to] = 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 getExistingCategories() {
 755                 $res = $this->mDb->select( 'categorylinks', array( 'cl_to', 'cl_sortkey_prefix' ),
 756                         array( 'cl_from' => $this->mId ), __METHOD__, $this->mOptions );
 757                 $arr = array();
 758                 foreach ( $res as $row ) {
 759                         $arr[$row->cl_to] = $row->cl_sortkey_prefix;
 760                 }
 761                 return $arr;
 762         }
 763
 764         /**
 765          * Get an array of existing interlanguage links, with the language code in the key and the
 766          * title in the value.
 767          *
 768          * @return array
 769          */
 770         private function getExistingInterlangs() {
 771                 $res = $this->mDb->select( 'langlinks', array( 'll_lang', 'll_title' ),
 772                         array( 'll_from' => $this->mId ), __METHOD__, $this->mOptions );
 773                 $arr = array();
 774                 foreach ( $res as $row ) {
 775                         $arr[$row->ll_lang] = $row->ll_title;
 776                 }
 777                 return $arr;
 778         }
 779
 780         /**
 781          * Get an array of existing inline interwiki links, as a 2-D array
 782          * @return array (prefix => array(dbkey => 1))
 783          */
 784         protected function getExistingInterwikis() {
 785                 $res = $this->mDb->select( 'iwlinks', array( 'iwl_prefix', 'iwl_title' ),
 786                         array( 'iwl_from' => $this->mId ), __METHOD__, $this->mOptions );
 787                 $arr = array();
 788                 foreach ( $res as $row ) {
 789                         if ( !isset( $arr[$row->iwl_prefix] ) ) {
 790                                 $arr[$row->iwl_prefix] = array();
 791                         }
 792                         $arr[$row->iwl_prefix][$row->iwl_title] = 1;
 793                 }
 794                 return $arr;
 795         }
 796
 797         /**
 798          * Get an array of existing categories, with the name in the key and sort key in the value.
 799          *
 800          * @return array
 801          */
 802         private function getExistingProperties() {
 803                 $res = $this->mDb->select( 'page_props', array( 'pp_propname', 'pp_value' ),
 804                         array( 'pp_page' => $this->mId ), __METHOD__, $this->mOptions );
 805                 $arr = array();
 806                 foreach ( $res as $row ) {
 807                         $arr[$row->pp_propname] = $row->pp_value;
 808                 }
 809                 return $arr;
 810         }
 811
 812         /**
 813          * Return the title object of the page being updated
 814          * @return Title
 815          */
 816         public function getTitle() {
 817                 return $this->mTitle;
 818         }
 819
 820         /**
 821          * Returns parser output
 822          * @since 1.19
 823          * @return ParserOutput
 824          */
 825         public function getParserOutput() {
 826                 return $this->mParserOutput;
 827         }
 828
 829         /**
 830          * Return the list of images used as generated by the parser
 831          * @return array
 832          */
 833         public function getImages() {
 834                 return $this->mImages;
 835         }
 836
 837         /**
 838          * Invalidate any necessary link lists related to page property changes
 839          * @param $changed
 840          */
 841         private function invalidateProperties( $changed ) {
 842                 global $wgPagePropLinkInvalidations;
 843
 844                 foreach ( $changed as $name => $value ) {
 845                         if ( isset( $wgPagePropLinkInvalidations[$name] ) ) {
 846                                 $inv = $wgPagePropLinkInvalidations[$name];
 847                                 if ( !is_array( $inv ) ) {
 848                                         $inv = array( $inv );
 849                                 }
 850                                 foreach ( $inv as $table ) {
 851                                         $update = new HTMLCacheUpdate( $this->mTitle, $table );
 852                                         $update->doUpdate();
 853                                 }
 854                         }
 855                 }
 856         }
 857 }