includes/LinksUpdate.php

   1 <?php
   2 /**
   3  * See docs/deferred.txt
   4  *
   5  * @todo document (e.g. one-sentence top-level class description).
   6  */
   7 class LinksUpdate {
   8
   9         /**@{{
  10          * @private
  11          */
  12         var $mId,            //!< Page ID of the article linked from
  13                 $mTitle,         //!< Title object of the article linked from
  14                 $mLinks,         //!< Map of title strings to IDs for the links in the document
  15                 $mImages,        //!< DB keys of the images used, in the array key only
  16                 $mTemplates,     //!< Map of title strings to IDs for the template references, including broken ones
  17                 $mExternals,     //!< URLs of external links, array key only
  18                 $mCategories,    //!< Map of category names to sort keys
  19                 $mInterlangs,    //!< Map of language codes to titles
  20                 $mProperties,    //!< Map of arbitrary name to value
  21                 $mDb,            //!< Database connection reference
  22                 $mOptions,       //!< SELECT options to be used (array)
  23                 $mRecursive;     //!< Whether to queue jobs for recursive updates
  24         /**@}}*/
  25
  26         /**
  27          * Constructor
  28          *
  29          * @param $title Title of the page we're updating
  30          * @param $parserOutput ParserOutput: output from a full parse of this page
  31          * @param $recursive Boolean: queue jobs for recursive updates?
  32          */
  33         function __construct( $title, $parserOutput, $recursive = true ) {
  34                 global $wgAntiLockFlags;
  35
  36                 if ( $wgAntiLockFlags & ALF_NO_LINK_LOCK ) {
  37                         $this->mOptions = array();
  38                 } else {
  39                         $this->mOptions = array( 'FOR UPDATE' );
  40                 }
  41                 $this->mDb = wfGetDB( DB_MASTER );
  42
  43                 if ( !is_object( $title ) ) {
  44                         throw new MWException( "The calling convention to LinksUpdate::LinksUpdate() has changed. " .
  45                                 "Please see Article::editUpdates() for an invocation example.\n" );
  46                 }
  47                 $this->mTitle = $title;
  48                 $this->mId = $title->getArticleID();
  49
  50                 $this->mParserOutput = $parserOutput;
  51                 $this->mLinks = $parserOutput->getLinks();
  52                 $this->mImages = $parserOutput->getImages();
  53                 $this->mTemplates = $parserOutput->getTemplates();
  54                 $this->mExternals = $parserOutput->getExternalLinks();
  55                 $this->mCategories = $parserOutput->getCategories();
  56                 $this->mProperties = $parserOutput->getProperties();
  57                 $this->mInterwikis = $parserOutput->getInterwikiLinks();
  58
  59                 # Convert the format of the interlanguage links
  60                 # I didn't want to change it in the ParserOutput, because that array is passed all
  61                 # the way back to the skin, so either a skin API break would be required, or an
  62                 # inefficient back-conversion.
  63                 $ill = $parserOutput->getLanguageLinks();
  64                 $this->mInterlangs = array();
  65                 foreach ( $ill as $link ) {
  66                         list( $key, $title ) = explode( ':', $link, 2 );
  67                         $this->mInterlangs[$key] = $title;
  68                 }
  69
  70                 foreach ( $this->mCategories as $cat => &$sortkey ) {
  71                         # If the sortkey is longer then 255 bytes,
  72                         # it truncated by DB, and then doesn't get
  73                         # matched when comparing existing vs current
  74                         # categories, causing bug 25254.
  75                         # Also. substr behaves weird when given "".
  76                         if ( $sortkey !== '' ) {
  77                                 $sortkey = substr( $sortkey, 0, 255 );
  78                         }
  79                 }
  80
  81                 $this->mRecursive = $recursive;
  82
  83                 wfRunHooks( 'LinksUpdateConstructed', array( &$this ) );
  84         }
  85
  86         /**
  87          * Update link tables with outgoing links from an updated article
  88          */
  89         public function doUpdate() {
  90                 global $wgUseDumbLinkUpdate;
  91
  92                 wfRunHooks( 'LinksUpdate', array( &$this ) );
  93                 if ( $wgUseDumbLinkUpdate ) {
  94                         $this->doDumbUpdate();
  95                 } else {
  96                         $this->doIncrementalUpdate();
  97                 }
  98                 wfRunHooks( 'LinksUpdateComplete', array( &$this ) );
  99         }
 100
 101         protected function doIncrementalUpdate() {
 102                 wfProfileIn( __METHOD__ );
 103
 104                 # Page links
 105                 $existing = $this->getExistingLinks();
 106                 $this->incrTableUpdate( 'pagelinks', 'pl', $this->getLinkDeletions( $existing ),
 107                         $this->getLinkInsertions( $existing ) );
 108
 109                 # Image links
 110                 $existing = $this->getExistingImages();
 111
 112                 $imageDeletes = $this->getImageDeletions( $existing );
 113                 $this->incrTableUpdate( 'imagelinks', 'il', $imageDeletes, $this->getImageInsertions( $existing ) );
 114
 115                 # Invalidate all image description pages which had links added or removed
 116                 $imageUpdates = $imageDeletes + array_diff_key( $this->mImages, $existing );
 117                 $this->invalidateImageDescriptions( $imageUpdates );
 118
 119                 # External links
 120                 $existing = $this->getExistingExternals();
 121                 $this->incrTableUpdate( 'externallinks', 'el', $this->getExternalDeletions( $existing ),
 122                 $this->getExternalInsertions( $existing ) );
 123
 124                 # Language links
 125                 $existing = $this->getExistingInterlangs();
 126                 $this->incrTableUpdate( 'langlinks', 'll', $this->getInterlangDeletions( $existing ),
 127                         $this->getInterlangInsertions( $existing ) );
 128
 129                 # Inline interwiki links
 130                 $existing = $this->getExistingInterwikis();
 131                 $this->incrTableUpdate( 'iwlinks', 'iwl', $this->getInterwikiDeletions( $existing ),
 132                         $this->getInterwikiInsertions( $existing ) );
 133
 134                 # Template links
 135                 $existing = $this->getExistingTemplates();
 136                 $this->incrTableUpdate( 'templatelinks', 'tl', $this->getTemplateDeletions( $existing ),
 137                         $this->getTemplateInsertions( $existing ) );
 138
 139                 # Category links
 140                 $existing = $this->getExistingCategories();
 141
 142                 $categoryDeletes = $this->getCategoryDeletions( $existing );
 143
 144                 $this->incrTableUpdate( 'categorylinks', 'cl', $categoryDeletes, $this->getCategoryInsertions( $existing ) );
 145
 146                 # Invalidate all categories which were added, deleted or changed (set symmetric difference)
 147                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 148                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 149                 $this->invalidateCategories( $categoryUpdates );
 150                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 151
 152                 # Page properties
 153                 $existing = $this->getExistingProperties();
 154
 155                 $propertiesDeletes = $this->getPropertyDeletions( $existing );
 156
 157                 $this->incrTableUpdate( 'page_props', 'pp', $propertiesDeletes, $this->getPropertyInsertions( $existing ) );
 158
 159                 # Invalidate the necessary pages
 160                 $changed = $propertiesDeletes + array_diff_assoc( $this->mProperties, $existing );
 161                 $this->invalidateProperties( $changed );
 162
 163                 # Refresh links of all pages including this page
 164                 # This will be in a separate transaction
 165                 if ( $this->mRecursive ) {
 166                         $this->queueRecursiveJobs();
 167                 }
 168
 169                 wfProfileOut( __METHOD__ );
 170         }
 171
 172         /**
 173          * Link update which clears the previous entries and inserts new ones
 174          * May be slower or faster depending on level of lock contention and write speed of DB
 175          * Also useful where link table corruption needs to be repaired, e.g. in refreshLinks.php
 176          */
 177         protected function doDumbUpdate() {
 178                 wfProfileIn( __METHOD__ );
 179
 180                 # Refresh category pages and image description pages
 181                 $existing = $this->getExistingCategories();
 182                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 183                 $categoryDeletes = array_diff_assoc( $existing, $this->mCategories );
 184                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 185                 $existing = $this->getExistingImages();
 186                 $imageUpdates = array_diff_key( $existing, $this->mImages ) + array_diff_key( $this->mImages, $existing );
 187
 188                 $this->dumbTableUpdate( 'pagelinks',     $this->getLinkInsertions(),     'pl_from' );
 189                 $this->dumbTableUpdate( 'imagelinks',    $this->getImageInsertions(),    'il_from' );
 190                 $this->dumbTableUpdate( 'categorylinks', $this->getCategoryInsertions(), 'cl_from' );
 191                 $this->dumbTableUpdate( 'templatelinks', $this->getTemplateInsertions(), 'tl_from' );
 192                 $this->dumbTableUpdate( 'externallinks', $this->getExternalInsertions(), 'el_from' );
 193                 $this->dumbTableUpdate( 'langlinks',     $this->getInterlangInsertions(),'ll_from' );
 194                 $this->dumbTableUpdate( 'iwlinks',       $this->getInterwikiInsertions(),'iwl_from' );
 195                 $this->dumbTableUpdate( 'page_props',    $this->getPropertyInsertions(), 'pp_page' );
 196
 197                 # Update the cache of all the category pages and image description
 198                 # pages which were changed, and fix the category table count
 199                 $this->invalidateCategories( $categoryUpdates );
 200                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 201                 $this->invalidateImageDescriptions( $imageUpdates );
 202
 203                 # Refresh links of all pages including this page
 204                 # This will be in a separate transaction
 205                 if ( $this->mRecursive ) {
 206                         $this->queueRecursiveJobs();
 207                 }
 208
 209                 wfProfileOut( __METHOD__ );
 210         }
 211
 212         function queueRecursiveJobs() {
 213                 global $wgUpdateRowsPerJob;
 214                 wfProfileIn( __METHOD__ );
 215
 216                 $cache = $this->mTitle->getBacklinkCache();
 217                 $batches = $cache->partition( 'templatelinks', $wgUpdateRowsPerJob );
 218                 if ( !$batches ) {
 219                         wfProfileOut( __METHOD__ );
 220                         return;
 221                 }
 222                 $jobs = array();
 223                 foreach ( $batches as $batch ) {
 224                         list( $start, $end ) = $batch;
 225                         $params = array(
 226                                 'start' => $start,
 227                                 'end' => $end,
 228                         );
 229                         $jobs[] = new RefreshLinksJob2( $this->mTitle, $params );
 230                 }
 231                 Job::batchInsert( $jobs );
 232
 233                 wfProfileOut( __METHOD__ );
 234         }
 235
 236         /**
 237          * Invalidate the cache of a list of pages from a single namespace
 238          *
 239          * @param $namespace Integer
 240          * @param $dbkeys Array
 241          */
 242         function invalidatePages( $namespace, $dbkeys ) {
 243                 if ( !count( $dbkeys ) ) {
 244                         return;
 245                 }
 246
 247                 /**
 248                  * Determine which pages need to be updated
 249                  * This is necessary to prevent the job queue from smashing the DB with
 250                  * large numbers of concurrent invalidations of the same page
 251                  */
 252                 $now = $this->mDb->timestamp();
 253                 $ids = array();
 254                 $res = $this->mDb->select( 'page', array( 'page_id' ),
 255                         array(
 256                                 'page_namespace' => $namespace,
 257                                 'page_title IN (' . $this->mDb->makeList( $dbkeys ) . ')',
 258                                 'page_touched < ' . $this->mDb->addQuotes( $now )
 259                         ), __METHOD__
 260                 );
 261                 foreach ( $res as $row ) {
 262                         $ids[] = $row->page_id;
 263                 }
 264                 if ( !count( $ids ) ) {
 265                         return;
 266                 }
 267
 268                 /**
 269                  * Do the update
 270                  * We still need the page_touched condition, in case the row has changed since
 271                  * the non-locking select above.
 272                  */
 273                 $this->mDb->update( 'page', array( 'page_touched' => $now ),
 274                         array(
 275                                 'page_id IN (' . $this->mDb->makeList( $ids ) . ')',
 276                                 'page_touched < ' . $this->mDb->addQuotes( $now )
 277                         ), __METHOD__
 278                 );
 279         }
 280
 281         function invalidateCategories( $cats ) {
 282                 $this->invalidatePages( NS_CATEGORY, array_keys( $cats ) );
 283         }
 284
 285         /**
 286          * Update all the appropriate counts in the category table.
 287          * @param $added associative array of category name => sort key
 288          * @param $deleted associative array of category name => sort key
 289          */
 290         function updateCategoryCounts( $added, $deleted ) {
 291                 $a = new Article($this->mTitle);
 292                 $a->updateCategoryCounts(
 293                         array_keys( $added ), array_keys( $deleted )
 294                 );
 295         }
 296
 297         function invalidateImageDescriptions( $images ) {
 298                 $this->invalidatePages( NS_FILE, array_keys( $images ) );
 299         }
 300
 301         function dumbTableUpdate( $table, $insertions, $fromField ) {
 302                 $this->mDb->delete( $table, array( $fromField => $this->mId ), __METHOD__ );
 303                 if ( count( $insertions ) ) {
 304                         # The link array was constructed without FOR UPDATE, so there may
 305                         # be collisions.  This may cause minor link table inconsistencies,
 306                         # which is better than crippling the site with lock contention.
 307                         $this->mDb->insert( $table, $insertions, __METHOD__, array( 'IGNORE' ) );
 308                 }
 309         }
 310
 311         /**
 312          * Update a table by doing a delete query then an insert query
 313          * @private
 314          */
 315         function incrTableUpdate( $table, $prefix, $deletions, $insertions ) {
 316                 if ( $table == 'page_props' ) {
 317                         $fromField = 'pp_page';
 318                 } else {
 319                         $fromField = "{$prefix}_from";
 320                 }
 321                 $where = array( $fromField => $this->mId );
 322                 if ( $table == 'pagelinks' || $table == 'templatelinks' || $table == 'iwlinks' ) {
 323                         if ( $table == 'iwlinks' ) {
 324                                 $baseKey = 'iwl_prefix';
 325                         } else {
 326                                 $baseKey = "{$prefix}_namespace";
 327                         }
 328                         $clause = $this->mDb->makeWhereFrom2d( $deletions, $baseKey, "{$prefix}_title" );
 329                         if ( $clause ) {
 330                                 $where[] = $clause;
 331                         } else {
 332                                 $where = false;
 333                         }
 334                 } else {
 335                         if ( $table == 'langlinks' ) {
 336                                 $toField = 'll_lang';
 337                         } elseif ( $table == 'page_props' ) {
 338                                 $toField = 'pp_propname';
 339                         } else {
 340                                 $toField = $prefix . '_to';
 341                         }
 342                         if ( count( $deletions ) ) {
 343                                 $where[] = "$toField IN (" . $this->mDb->makeList( array_keys( $deletions ) ) . ')';
 344                         } else {
 345                                 $where = false;
 346                         }
 347                 }
 348                 if ( $where ) {
 349                         $this->mDb->delete( $table, $where, __METHOD__ );
 350                 }
 351                 if ( count( $insertions ) ) {
 352                         $this->mDb->insert( $table, $insertions, __METHOD__, 'IGNORE' );
 353                 }
 354         }
 355
 356
 357         /**
 358          * Get an array of pagelinks insertions for passing to the DB
 359          * Skips the titles specified by the 2-D array $existing
 360          * @private
 361          */
 362         function getLinkInsertions( $existing = array() ) {
 363                 $arr = array();
 364                 foreach( $this->mLinks as $ns => $dbkeys ) {
 365                         $diffs = isset( $existing[$ns] ) ? array_diff_key( $dbkeys, $existing[$ns] ) : $dbkeys;
 366                         foreach ( $diffs as $dbk => $id ) {
 367                                 $arr[] = array(
 368                                         'pl_from'      => $this->mId,
 369                                         'pl_namespace' => $ns,
 370                                         'pl_title'     => $dbk
 371                                 );
 372                         }
 373                 }
 374                 return $arr;
 375         }
 376
 377         /**
 378          * Get an array of template insertions. Like getLinkInsertions()
 379          * @private
 380          */
 381         function getTemplateInsertions( $existing = array() ) {
 382                 $arr = array();
 383                 foreach( $this->mTemplates as $ns => $dbkeys ) {
 384                         $diffs = isset( $existing[$ns] ) ? array_diff_key( $dbkeys, $existing[$ns] ) : $dbkeys;
 385                         foreach ( $diffs as $dbk => $id ) {
 386                                 $arr[] = array(
 387                                         'tl_from'      => $this->mId,
 388                                         'tl_namespace' => $ns,
 389                                         'tl_title'     => $dbk
 390                                 );
 391                         }
 392                 }
 393                 return $arr;
 394         }
 395
 396         /**
 397          * Get an array of image insertions
 398          * Skips the names specified in $existing
 399          * @private
 400          */
 401         function getImageInsertions( $existing = array() ) {
 402                 $arr = array();
 403                 $diffs = array_diff_key( $this->mImages, $existing );
 404                 foreach( $diffs as $iname => $dummy ) {
 405                         $arr[] = array(
 406                                 'il_from' => $this->mId,
 407                                 'il_to'   => $iname
 408                         );
 409                 }
 410                 return $arr;
 411         }
 412
 413         /**
 414          * Get an array of externallinks insertions. Skips the names specified in $existing
 415          * @private
 416          */
 417         function getExternalInsertions( $existing = array() ) {
 418                 $arr = array();
 419                 $diffs = array_diff_key( $this->mExternals, $existing );
 420                 foreach( $diffs as $url => $dummy ) {
 421                         $arr[] = array(
 422                                 'el_from'   => $this->mId,
 423                                 'el_to'     => $url,
 424                                 'el_index'  => wfMakeUrlIndex( $url ),
 425                         );
 426                 }
 427                 return $arr;
 428         }
 429
 430         /**
 431          * Get an array of category insertions
 432          *
 433          * @param $existing Array mapping existing category names to sort keys. If both
 434          * match a link in $this, the link will be omitted from the output
 435          * @private
 436          */
 437         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          * @private
 478          */
 479         function getInterlangInsertions( $existing = array() ) {
 480             $diffs = array_diff_assoc( $this->mInterlangs, $existing );
 481             $arr = array();
 482             foreach( $diffs as $lang => $title ) {
 483                 $arr[] = array(
 484                     'll_from'  => $this->mId,
 485                     'll_lang'  => $lang,
 486                     'll_title' => $title
 487                 );
 488             }
 489             return $arr;
 490         }
 491
 492         /**
 493          * Get an array of page property insertions
 494          */
 495         function getPropertyInsertions( $existing = array() ) {
 496                 $diffs = array_diff_assoc( $this->mProperties, $existing );
 497                 $arr = array();
 498                 foreach ( $diffs as $name => $value ) {
 499                         $arr[] = array(
 500                                 'pp_page'      => $this->mId,
 501                                 'pp_propname'  => $name,
 502                                 'pp_value'     => $value,
 503                         );
 504                 }
 505                 return $arr;
 506         }
 507
 508         /**
 509          * Get an array of interwiki insertions for passing to the DB
 510          * Skips the titles specified by the 2-D array $existing
 511          * @private
 512          */
 513         function getInterwikiInsertions( $existing = array() ) {
 514                 $arr = array();
 515                 foreach( $this->mInterwikis as $prefix => $dbkeys ) {
 516                         $diffs = isset( $existing[$prefix] ) ? array_diff_key( $dbkeys, $existing[$prefix] ) : $dbkeys;
 517                         foreach ( $diffs as $dbk => $id ) {
 518                                 $arr[] = array(
 519                                         'iwl_from'   => $this->mId,
 520                                         'iwl_prefix' => $prefix,
 521                                         'iwl_title'  => $dbk
 522                                 );
 523                         }
 524                 }
 525                 return $arr;
 526         }
 527
 528         /**
 529          * Given an array of existing links, returns those links which are not in $this
 530          * and thus should be deleted.
 531          * @private
 532          */
 533         function getLinkDeletions( $existing ) {
 534                 $del = array();
 535                 foreach ( $existing as $ns => $dbkeys ) {
 536                         if ( isset( $this->mLinks[$ns] ) ) {
 537                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mLinks[$ns] );
 538                         } else {
 539                                 $del[$ns] = $existing[$ns];
 540                         }
 541                 }
 542                 return $del;
 543         }
 544
 545         /**
 546          * Given an array of existing templates, returns those templates which are not in $this
 547          * and thus should be deleted.
 548          * @private
 549          */
 550         function getTemplateDeletions( $existing ) {
 551                 $del = array();
 552                 foreach ( $existing as $ns => $dbkeys ) {
 553                         if ( isset( $this->mTemplates[$ns] ) ) {
 554                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mTemplates[$ns] );
 555                         } else {
 556                                 $del[$ns] = $existing[$ns];
 557                         }
 558                 }
 559                 return $del;
 560         }
 561
 562         /**
 563          * Given an array of existing images, returns those images which are not in $this
 564          * and thus should be deleted.
 565          * @private
 566          */
 567         function getImageDeletions( $existing ) {
 568                 return array_diff_key( $existing, $this->mImages );
 569         }
 570
 571         /**
 572          * Given an array of existing external links, returns those links which are not
 573          * in $this and thus should be deleted.
 574          * @private
 575          */
 576         function getExternalDeletions( $existing ) {
 577                 return array_diff_key( $existing, $this->mExternals );
 578         }
 579
 580         /**
 581          * Given an array of existing categories, returns those categories which are not in $this
 582          * and thus should be deleted.
 583          * @private
 584          */
 585         function getCategoryDeletions( $existing ) {
 586                 return array_diff_assoc( $existing, $this->mCategories );
 587         }
 588
 589         /**
 590          * Given an array of existing interlanguage links, returns those links which are not
 591          * in $this and thus should be deleted.
 592          * @private
 593          */
 594         function getInterlangDeletions( $existing ) {
 595             return array_diff_assoc( $existing, $this->mInterlangs );
 596         }
 597
 598         /**
 599          * Get array of properties which should be deleted.
 600          * @private
 601          */
 602         function getPropertyDeletions( $existing ) {
 603                 return array_diff_assoc( $existing, $this->mProperties );
 604         }
 605
 606         /**
 607          * Given an array of existing interwiki links, returns those links which are not in $this
 608          * and thus should be deleted.
 609          * @private
 610          */
 611         function getInterwikiDeletions( $existing ) {
 612                 $del = array();
 613                 foreach ( $existing as $prefix => $dbkeys ) {
 614                         if ( isset( $this->mInterwikis[$prefix] ) ) {
 615                                 $del[$prefix] = array_diff_key( $existing[$prefix], $this->mInterwikis[$prefix] );
 616                         } else {
 617                                 $del[$prefix] = $existing[$prefix];
 618                         }
 619                 }
 620                 return $del;
 621         }
 622
 623         /**
 624          * Get an array of existing links, as a 2-D array
 625          * @private
 626          */
 627         function getExistingLinks() {
 628                 $res = $this->mDb->select( 'pagelinks', array( 'pl_namespace', 'pl_title' ),
 629                         array( 'pl_from' => $this->mId ), __METHOD__, $this->mOptions );
 630                 $arr = array();
 631                 foreach ( $res as $row ) {
 632                         if ( !isset( $arr[$row->pl_namespace] ) ) {
 633                                 $arr[$row->pl_namespace] = array();
 634                         }
 635                         $arr[$row->pl_namespace][$row->pl_title] = 1;
 636                 }
 637                 return $arr;
 638         }
 639
 640         /**
 641          * Get an array of existing templates, as a 2-D array
 642          * @private
 643          */
 644         function getExistingTemplates() {
 645                 $res = $this->mDb->select( 'templatelinks', array( 'tl_namespace', 'tl_title' ),
 646                         array( 'tl_from' => $this->mId ), __METHOD__, $this->mOptions );
 647                 $arr = array();
 648                 foreach ( $res as $row ) {
 649                         if ( !isset( $arr[$row->tl_namespace] ) ) {
 650                                 $arr[$row->tl_namespace] = array();
 651                         }
 652                         $arr[$row->tl_namespace][$row->tl_title] = 1;
 653                 }
 654                 return $arr;
 655         }
 656
 657         /**
 658          * Get an array of existing images, image names in the keys
 659          * @private
 660          */
 661         function getExistingImages() {
 662                 $res = $this->mDb->select( 'imagelinks', array( 'il_to' ),
 663                         array( 'il_from' => $this->mId ), __METHOD__, $this->mOptions );
 664                 $arr = array();
 665                 foreach ( $res as $row ) {
 666                         $arr[$row->il_to] = 1;
 667                 }
 668                 return $arr;
 669         }
 670
 671         /**
 672          * Get an array of existing external links, URLs in the keys
 673          * @private
 674          */
 675         function getExistingExternals() {
 676                 $res = $this->mDb->select( 'externallinks', array( 'el_to' ),
 677                         array( 'el_from' => $this->mId ), __METHOD__, $this->mOptions );
 678                 $arr = array();
 679                 foreach ( $res as $row ) {
 680                         $arr[$row->el_to] = 1;
 681                 }
 682                 return $arr;
 683         }
 684
 685         /**
 686          * Get an array of existing categories, with the name in the key and sort key in the value.
 687          * @private
 688          */
 689         function getExistingCategories() {
 690                 $res = $this->mDb->select( 'categorylinks', array( 'cl_to', 'cl_sortkey_prefix' ),
 691                         array( 'cl_from' => $this->mId ), __METHOD__, $this->mOptions );
 692                 $arr = array();
 693                 foreach ( $res as $row ) {
 694                         $arr[$row->cl_to] = $row->cl_sortkey_prefix;
 695                 }
 696                 return $arr;
 697         }
 698
 699         /**
 700          * Get an array of existing interlanguage links, with the language code in the key and the
 701          * title in the value.
 702          * @private
 703          */
 704         function getExistingInterlangs() {
 705                 $res = $this->mDb->select( 'langlinks', array( 'll_lang', 'll_title' ),
 706                         array( 'll_from' => $this->mId ), __METHOD__, $this->mOptions );
 707                 $arr = array();
 708                 foreach ( $res as $row ) {
 709                         $arr[$row->ll_lang] = $row->ll_title;
 710                 }
 711                 return $arr;
 712         }
 713
 714         /**
 715          * Get an array of existing inline interwiki links, as a 2-D array
 716          * @return array (prefix => array(dbkey => 1))
 717          */
 718         protected function getExistingInterwikis() {
 719                 $res = $this->mDb->select( 'iwlinks', array( 'iwl_prefix', 'iwl_title' ),
 720                         array( 'iwl_from' => $this->mId ), __METHOD__, $this->mOptions );
 721                 $arr = array();
 722                 foreach ( $res as $row ) {
 723                         if ( !isset( $arr[$row->iwl_prefix] ) ) {
 724                                 $arr[$row->iwl_prefix] = array();
 725                         }
 726                         $arr[$row->iwl_prefix][$row->iwl_title] = 1;
 727                 }
 728                 return $arr;
 729         }
 730
 731         /**
 732          * Get an array of existing categories, with the name in the key and sort key in the value.
 733          * @private
 734          */
 735         function getExistingProperties() {
 736                 $res = $this->mDb->select( 'page_props', array( 'pp_propname', 'pp_value' ),
 737                         array( 'pp_page' => $this->mId ), __METHOD__, $this->mOptions );
 738                 $arr = array();
 739                 foreach ( $res as $row ) {
 740                         $arr[$row->pp_propname] = $row->pp_value;
 741                 }
 742                 return $arr;
 743         }
 744
 745
 746         /**
 747          * Return the title object of the page being updated
 748          */
 749         function getTitle() {
 750                 return $this->mTitle;
 751         }
 752
 753         /**
 754          * Return the list of images used as generated by the parser
 755          */
 756         public function getImages() {
 757                 return $this->mImages;
 758         }
 759
 760         /**
 761          * Invalidate any necessary link lists related to page property changes
 762          */
 763         function invalidateProperties( $changed ) {
 764                 global $wgPagePropLinkInvalidations;
 765
 766                 foreach ( $changed as $name => $value ) {
 767                         if ( isset( $wgPagePropLinkInvalidations[$name] ) ) {
 768                                 $inv = $wgPagePropLinkInvalidations[$name];
 769                                 if ( !is_array( $inv ) ) {
 770                                         $inv = array( $inv );
 771                                 }
 772                                 foreach ( $inv as $table ) {
 773                                         $update = new HTMLCacheUpdate( $this->mTitle, $table );
 774                                         $update->doUpdate();
 775                                 }
 776                         }
 777                 }
 778         }
 779 }