includes/LinksUpdate.php

   1 <?php
   2 /**
   3  * See docs/deferred.txt
   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  * @todo document (e.g. one-sentence top-level class description).
  21  */
  22 class LinksUpdate {
  23
  24         /**@{{
  25          * @private
  26          */
  27         var $mId,            //!< Page ID of the article linked from
  28                 $mTitle,         //!< Title object of the article linked from
  29                 $mLinks,         //!< Map of title strings to IDs for the links in the document
  30                 $mImages,        //!< DB keys of the images used, in the array key only
  31                 $mTemplates,     //!< Map of title strings to IDs for the template references, including broken ones
  32                 $mExternals,     //!< URLs of external links, array key only
  33                 $mCategories,    //!< Map of category names to sort keys
  34                 $mInterlangs,    //!< Map of language codes to titles
  35                 $mProperties,    //!< Map of arbitrary name to value
  36                 $mDb,            //!< Database connection reference
  37                 $mOptions,       //!< SELECT options to be used (array)
  38                 $mRecursive;     //!< Whether to queue jobs for recursive updates
  39         /**@}}*/
  40
  41         /**
  42          * Constructor
  43          *
  44          * @param $title Title of the page we're updating
  45          * @param $parserOutput ParserOutput: output from a full parse of this page
  46          * @param $recursive Boolean: queue jobs for recursive updates?
  47          */
  48         function __construct( $title, $parserOutput, $recursive = true ) {
  49                 global $wgAntiLockFlags;
  50
  51                 if ( $wgAntiLockFlags & ALF_NO_LINK_LOCK ) {
  52                         $this->mOptions = array();
  53                 } else {
  54                         $this->mOptions = array( 'FOR UPDATE' );
  55                 }
  56                 $this->mDb = wfGetDB( DB_MASTER );
  57
  58                 if ( !is_object( $title ) ) {
  59                         throw new MWException( "The calling convention to LinksUpdate::LinksUpdate() has changed. " .
  60                                 "Please see Article::editUpdates() for an invocation example.\n" );
  61                 }
  62                 $this->mTitle = $title;
  63                 $this->mId = $title->getArticleID();
  64
  65                 $this->mParserOutput = $parserOutput;
  66                 $this->mLinks = $parserOutput->getLinks();
  67                 $this->mImages = $parserOutput->getImages();
  68                 $this->mTemplates = $parserOutput->getTemplates();
  69                 $this->mExternals = $parserOutput->getExternalLinks();
  70                 $this->mCategories = $parserOutput->getCategories();
  71                 $this->mProperties = $parserOutput->getProperties();
  72                 $this->mInterwikis = $parserOutput->getInterwikiLinks();
  73
  74                 # Convert the format of the interlanguage links
  75                 # I didn't want to change it in the ParserOutput, because that array is passed all
  76                 # the way back to the skin, so either a skin API break would be required, or an
  77                 # inefficient back-conversion.
  78                 $ill = $parserOutput->getLanguageLinks();
  79                 $this->mInterlangs = array();
  80                 foreach ( $ill as $link ) {
  81                         list( $key, $title ) = explode( ':', $link, 2 );
  82                         $this->mInterlangs[$key] = $title;
  83                 }
  84
  85                 foreach ( $this->mCategories as &$sortkey ) {
  86                         # If the sortkey is longer then 255 bytes,
  87                         # it truncated by DB, and then doesn't get
  88                         # matched when comparing existing vs current
  89                         # categories, causing bug 25254.
  90                         # Also. substr behaves weird when given "".
  91                         if ( $sortkey !== '' ) {
  92                                 $sortkey = substr( $sortkey, 0, 255 );
  93                         }
  94                 }
  95
  96                 $this->mRecursive = $recursive;
  97
  98                 wfRunHooks( 'LinksUpdateConstructed', array( &$this ) );
  99         }
 100
 101         /**
 102          * Update link tables with outgoing links from an updated article
 103          */
 104         public function doUpdate() {
 105                 global $wgUseDumbLinkUpdate;
 106
 107                 wfRunHooks( 'LinksUpdate', array( &$this ) );
 108                 if ( $wgUseDumbLinkUpdate ) {
 109                         $this->doDumbUpdate();
 110                 } else {
 111                         $this->doIncrementalUpdate();
 112                 }
 113                 wfRunHooks( 'LinksUpdateComplete', array( &$this ) );
 114         }
 115
 116         protected function doIncrementalUpdate() {
 117                 wfProfileIn( __METHOD__ );
 118
 119                 # Page links
 120                 $existing = $this->getExistingLinks();
 121                 $this->incrTableUpdate( 'pagelinks', 'pl', $this->getLinkDeletions( $existing ),
 122                         $this->getLinkInsertions( $existing ) );
 123
 124                 # Image links
 125                 $existing = $this->getExistingImages();
 126
 127                 $imageDeletes = $this->getImageDeletions( $existing );
 128                 $this->incrTableUpdate( 'imagelinks', 'il', $imageDeletes,
 129                         $this->getImageInsertions( $existing ) );
 130
 131                 # Invalidate all image description pages which had links added or removed
 132                 $imageUpdates = $imageDeletes + array_diff_key( $this->mImages, $existing );
 133                 $this->invalidateImageDescriptions( $imageUpdates );
 134
 135                 # External links
 136                 $existing = $this->getExistingExternals();
 137                 $this->incrTableUpdate( 'externallinks', 'el', $this->getExternalDeletions( $existing ),
 138                         $this->getExternalInsertions( $existing ) );
 139
 140                 # Language links
 141                 $existing = $this->getExistingInterlangs();
 142                 $this->incrTableUpdate( 'langlinks', 'll', $this->getInterlangDeletions( $existing ),
 143                         $this->getInterlangInsertions( $existing ) );
 144
 145                 # Inline interwiki links
 146                 $existing = $this->getExistingInterwikis();
 147                 $this->incrTableUpdate( 'iwlinks', 'iwl', $this->getInterwikiDeletions( $existing ),
 148                         $this->getInterwikiInsertions( $existing ) );
 149
 150                 # Template links
 151                 $existing = $this->getExistingTemplates();
 152                 $this->incrTableUpdate( 'templatelinks', 'tl', $this->getTemplateDeletions( $existing ),
 153                         $this->getTemplateInsertions( $existing ) );
 154
 155                 # Category links
 156                 $existing = $this->getExistingCategories();
 157
 158                 $categoryDeletes = $this->getCategoryDeletions( $existing );
 159
 160                 $this->incrTableUpdate( 'categorylinks', 'cl', $categoryDeletes,
 161                         $this->getCategoryInsertions( $existing ) );
 162
 163                 # Invalidate all categories which were added, deleted or changed (set symmetric difference)
 164                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 165                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 166                 $this->invalidateCategories( $categoryUpdates );
 167                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 168
 169                 # Page properties
 170                 $existing = $this->getExistingProperties();
 171
 172                 $propertiesDeletes = $this->getPropertyDeletions( $existing );
 173
 174                 $this->incrTableUpdate( 'page_props', 'pp', $propertiesDeletes,
 175                         $this->getPropertyInsertions( $existing ) );
 176
 177                 # Invalidate the necessary pages
 178                 $changed = $propertiesDeletes + array_diff_assoc( $this->mProperties, $existing );
 179                 $this->invalidateProperties( $changed );
 180
 181                 # Refresh links of all pages including this page
 182                 # This will be in a separate transaction
 183                 if ( $this->mRecursive ) {
 184                         $this->queueRecursiveJobs();
 185                 }
 186
 187                 wfProfileOut( __METHOD__ );
 188         }
 189
 190         /**
 191          * Link update which clears the previous entries and inserts new ones
 192          * May be slower or faster depending on level of lock contention and write speed of DB
 193          * Also useful where link table corruption needs to be repaired, e.g. in refreshLinks.php
 194          */
 195         protected function doDumbUpdate() {
 196                 wfProfileIn( __METHOD__ );
 197
 198                 # Refresh category pages and image description pages
 199                 $existing = $this->getExistingCategories();
 200                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 201                 $categoryDeletes = array_diff_assoc( $existing, $this->mCategories );
 202                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 203                 $existing = $this->getExistingImages();
 204                 $imageUpdates = array_diff_key( $existing, $this->mImages ) + array_diff_key( $this->mImages, $existing );
 205
 206                 $this->dumbTableUpdate( 'pagelinks',     $this->getLinkInsertions(),     'pl_from' );
 207                 $this->dumbTableUpdate( 'imagelinks',    $this->getImageInsertions(),    'il_from' );
 208                 $this->dumbTableUpdate( 'categorylinks', $this->getCategoryInsertions(), 'cl_from' );
 209                 $this->dumbTableUpdate( 'templatelinks', $this->getTemplateInsertions(), 'tl_from' );
 210                 $this->dumbTableUpdate( 'externallinks', $this->getExternalInsertions(), 'el_from' );
 211                 $this->dumbTableUpdate( 'langlinks',     $this->getInterlangInsertions(),'ll_from' );
 212                 $this->dumbTableUpdate( 'iwlinks',       $this->getInterwikiInsertions(),'iwl_from' );
 213                 $this->dumbTableUpdate( 'page_props',    $this->getPropertyInsertions(), 'pp_page' );
 214
 215                 # Update the cache of all the category pages and image description
 216                 # pages which were changed, and fix the category table count
 217                 $this->invalidateCategories( $categoryUpdates );
 218                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 219                 $this->invalidateImageDescriptions( $imageUpdates );
 220
 221                 # Refresh links of all pages including this page
 222                 # This will be in a separate transaction
 223                 if ( $this->mRecursive ) {
 224                         $this->queueRecursiveJobs();
 225                 }
 226
 227                 wfProfileOut( __METHOD__ );
 228         }
 229
 230         function queueRecursiveJobs() {
 231                 global $wgUpdateRowsPerJob;
 232                 wfProfileIn( __METHOD__ );
 233
 234                 $cache = $this->mTitle->getBacklinkCache();
 235                 $batches = $cache->partition( 'templatelinks', $wgUpdateRowsPerJob );
 236                 if ( !$batches ) {
 237                         wfProfileOut( __METHOD__ );
 238                         return;
 239                 }
 240                 $jobs = array();
 241                 foreach ( $batches as $batch ) {
 242                         list( $start, $end ) = $batch;
 243                         $params = array(
 244                                 'table' => 'templatelinks',
 245                                 'start' => $start,
 246                                 'end' => $end,
 247                         );
 248                         $jobs[] = new RefreshLinksJob2( $this->mTitle, $params );
 249                 }
 250                 Job::batchInsert( $jobs );
 251
 252                 wfProfileOut( __METHOD__ );
 253         }
 254
 255         /**
 256          * Invalidate the cache of a list of pages from a single namespace
 257          *
 258          * @param $namespace Integer
 259          * @param $dbkeys Array
 260          */
 261         function invalidatePages( $namespace, $dbkeys ) {
 262                 if ( !count( $dbkeys ) ) {
 263                         return;
 264                 }
 265
 266                 /**
 267                  * Determine which pages need to be updated
 268                  * This is necessary to prevent the job queue from smashing the DB with
 269                  * large numbers of concurrent invalidations of the same page
 270                  */
 271                 $now = $this->mDb->timestamp();
 272                 $ids = array();
 273                 $res = $this->mDb->select( 'page', array( 'page_id' ),
 274                         array(
 275                                 'page_namespace' => $namespace,
 276                                 'page_title IN (' . $this->mDb->makeList( $dbkeys ) . ')',
 277                                 'page_touched < ' . $this->mDb->addQuotes( $now )
 278                         ), __METHOD__
 279                 );
 280                 foreach ( $res as $row ) {
 281                         $ids[] = $row->page_id;
 282                 }
 283                 if ( !count( $ids ) ) {
 284                         return;
 285                 }
 286
 287                 /**
 288                  * Do the update
 289                  * We still need the page_touched condition, in case the row has changed since
 290                  * the non-locking select above.
 291                  */
 292                 $this->mDb->update( 'page', array( 'page_touched' => $now ),
 293                         array(
 294                                 'page_id IN (' . $this->mDb->makeList( $ids ) . ')',
 295                                 'page_touched < ' . $this->mDb->addQuotes( $now )
 296                         ), __METHOD__
 297                 );
 298         }
 299
 300         /**
 301          * @param $cats
 302          */
 303         function invalidateCategories( $cats ) {
 304                 $this->invalidatePages( NS_CATEGORY, array_keys( $cats ) );
 305         }
 306
 307         /**
 308          * Update all the appropriate counts in the category table.
 309          * @param $added array associative array of category name => sort key
 310          * @param $deleted array associative array of category name => sort key
 311          */
 312         function updateCategoryCounts( $added, $deleted ) {
 313                 $a = WikiPage::factory( $this->mTitle );
 314                 $a->updateCategoryCounts(
 315                         array_keys( $added ), array_keys( $deleted )
 316                 );
 317         }
 318
 319         /**
 320          * @param $images
 321          */
 322         function invalidateImageDescriptions( $images ) {
 323                 $this->invalidatePages( NS_FILE, array_keys( $images ) );
 324         }
 325
 326         /**
 327          * @param $table
 328          * @param $insertions
 329          * @param $fromField
 330          */
 331         private function dumbTableUpdate( $table, $insertions, $fromField ) {
 332                 $this->mDb->delete( $table, array( $fromField => $this->mId ), __METHOD__ );
 333                 if ( count( $insertions ) ) {
 334                         # The link array was constructed without FOR UPDATE, so there may
 335                         # be collisions.  This may cause minor link table inconsistencies,
 336                         # which is better than crippling the site with lock contention.
 337                         $this->mDb->insert( $table, $insertions, __METHOD__, array( 'IGNORE' ) );
 338                 }
 339         }
 340
 341         /**
 342          * Update a table by doing a delete query then an insert query
 343          * @param $table
 344          * @param $prefix
 345          * @param $deletions
 346          * @param $insertions
 347          */
 348         function incrTableUpdate( $table, $prefix, $deletions, $insertions ) {
 349                 if ( $table == 'page_props' ) {
 350                         $fromField = 'pp_page';
 351                 } else {
 352                         $fromField = "{$prefix}_from";
 353                 }
 354                 $where = array( $fromField => $this->mId );
 355                 if ( $table == 'pagelinks' || $table == 'templatelinks' || $table == 'iwlinks' ) {
 356                         if ( $table == 'iwlinks' ) {
 357                                 $baseKey = 'iwl_prefix';
 358                         } else {
 359                                 $baseKey = "{$prefix}_namespace";
 360                         }
 361                         $clause = $this->mDb->makeWhereFrom2d( $deletions, $baseKey, "{$prefix}_title" );
 362                         if ( $clause ) {
 363                                 $where[] = $clause;
 364                         } else {
 365                                 $where = false;
 366                         }
 367                 } else {
 368                         if ( $table == 'langlinks' ) {
 369                                 $toField = 'll_lang';
 370                         } elseif ( $table == 'page_props' ) {
 371                                 $toField = 'pp_propname';
 372                         } else {
 373                                 $toField = $prefix . '_to';
 374                         }
 375                         if ( count( $deletions ) ) {
 376                                 $where[] = "$toField IN (" . $this->mDb->makeList( array_keys( $deletions ) ) . ')';
 377                         } else {
 378                                 $where = false;
 379                         }
 380                 }
 381                 if ( $where ) {
 382                         $this->mDb->delete( $table, $where, __METHOD__ );
 383                 }
 384                 if ( count( $insertions ) ) {
 385                         $this->mDb->insert( $table, $insertions, __METHOD__, 'IGNORE' );
 386                 }
 387         }
 388
 389         /**
 390          * Get an array of pagelinks insertions for passing to the DB
 391          * Skips the titles specified by the 2-D array $existing
 392          * @param $existing array
 393          * @return array
 394          */
 395         private function getLinkInsertions( $existing = array() ) {
 396                 $arr = array();
 397                 foreach( $this->mLinks as $ns => $dbkeys ) {
 398                         $diffs = isset( $existing[$ns] )
 399                                 ? array_diff_key( $dbkeys, $existing[$ns] )
 400                                 : $dbkeys;
 401                         foreach ( $diffs as $dbk => $id ) {
 402                                 $arr[] = array(
 403                                         'pl_from'      => $this->mId,
 404                                         'pl_namespace' => $ns,
 405                                         'pl_title'     => $dbk
 406                                 );
 407                         }
 408                 }
 409                 return $arr;
 410         }
 411
 412         /**
 413          * Get an array of template insertions. Like getLinkInsertions()
 414          * @param $existing array
 415          * @return array
 416          */
 417         private function getTemplateInsertions( $existing = array() ) {
 418                 $arr = array();
 419                 foreach( $this->mTemplates as $ns => $dbkeys ) {
 420                         $diffs = isset( $existing[$ns] ) ? array_diff_key( $dbkeys, $existing[$ns] ) : $dbkeys;
 421                         foreach ( $diffs as $dbk => $id ) {
 422                                 $arr[] = array(
 423                                         'tl_from'      => $this->mId,
 424                                         'tl_namespace' => $ns,
 425                                         'tl_title'     => $dbk
 426                                 );
 427                         }
 428                 }
 429                 return $arr;
 430         }
 431
 432         /**
 433          * Get an array of image insertions
 434          * Skips the names specified in $existing
 435          * @param $existing array
 436          * @return array
 437          */
 438         private function getImageInsertions( $existing = array() ) {
 439                 $arr = array();
 440                 $diffs = array_diff_key( $this->mImages, $existing );
 441                 foreach( $diffs as $iname => $dummy ) {
 442                         $arr[] = array(
 443                                 'il_from' => $this->mId,
 444                                 'il_to'   => $iname
 445                         );
 446                 }
 447                 return $arr;
 448         }
 449
 450         /**
 451          * Get an array of externallinks insertions. Skips the names specified in $existing
 452          * @param $existing array
 453          * @return array
 454          */
 455         private function getExternalInsertions( $existing = array() ) {
 456                 $arr = array();
 457                 $diffs = array_diff_key( $this->mExternals, $existing );
 458                 foreach( $diffs as $url => $dummy ) {
 459                         foreach( wfMakeUrlIndexes( $url ) as $index ) {
 460                                 $arr[] = array(
 461                                         'el_from'   => $this->mId,
 462                                         'el_to'     => $url,
 463                                         'el_index'  => $index,
 464                                 );
 465                         }
 466                 }
 467                 return $arr;
 468         }
 469
 470         /**
 471          * Get an array of category insertions
 472          *
 473          * @param $existing array mapping existing category names to sort keys. If both
 474          * match a link in $this, the link will be omitted from the output
 475          *
 476          * @return array
 477          */
 478         private function getCategoryInsertions( $existing = array() ) {
 479                 global $wgContLang, $wgCategoryCollation;
 480                 $diffs = array_diff_assoc( $this->mCategories, $existing );
 481                 $arr = array();
 482                 foreach ( $diffs as $name => $prefix ) {
 483                         $nt = Title::makeTitleSafe( NS_CATEGORY, $name );
 484                         $wgContLang->findVariantLink( $name, $nt, true );
 485
 486                         if ( $this->mTitle->getNamespace() == NS_CATEGORY ) {
 487                                 $type = 'subcat';
 488                         } elseif ( $this->mTitle->getNamespace() == NS_FILE ) {
 489                                 $type = 'file';
 490                         } else {
 491                                 $type = 'page';
 492                         }
 493
 494                         # Treat custom sortkeys as a prefix, so that if multiple
 495                         # things are forced to sort as '*' or something, they'll
 496                         # sort properly in the category rather than in page_id
 497                         # order or such.
 498                         $sortkey = Collation::singleton()->getSortKey(
 499                                 $this->mTitle->getCategorySortkey( $prefix ) );
 500
 501                         $arr[] = array(
 502                                 'cl_from'    => $this->mId,
 503                                 'cl_to'      => $name,
 504                                 'cl_sortkey' => $sortkey,
 505                                 'cl_timestamp' => $this->mDb->timestamp(),
 506                                 'cl_sortkey_prefix' => $prefix,
 507                                 'cl_collation' => $wgCategoryCollation,
 508                                 'cl_type' => $type,
 509                         );
 510                 }
 511                 return $arr;
 512         }
 513
 514         /**
 515          * Get an array of interlanguage link insertions
 516          *
 517          * @param $existing Array mapping existing language codes to titles
 518          *
 519          * @return array
 520          */
 521         private function getInterlangInsertions( $existing = array() ) {
 522                 $diffs = array_diff_assoc( $this->mInterlangs, $existing );
 523                 $arr = array();
 524                 foreach( $diffs as $lang => $title ) {
 525                         $arr[] = array(
 526                                 'll_from'  => $this->mId,
 527                                 'll_lang'  => $lang,
 528                                 'll_title' => $title
 529                         );
 530                 }
 531                 return $arr;
 532         }
 533
 534         /**
 535          * Get an array of page property insertions
 536          * @param $existing array
 537          * @return array
 538          */
 539         function getPropertyInsertions( $existing = array() ) {
 540                 $diffs = array_diff_assoc( $this->mProperties, $existing );
 541                 $arr = array();
 542                 foreach ( $diffs as $name => $value ) {
 543                         $arr[] = array(
 544                                 'pp_page'      => $this->mId,
 545                                 'pp_propname'  => $name,
 546                                 'pp_value'     => $value,
 547                         );
 548                 }
 549                 return $arr;
 550         }
 551
 552         /**
 553          * Get an array of interwiki insertions for passing to the DB
 554          * Skips the titles specified by the 2-D array $existing
 555          * @param $existing array
 556          * @return array
 557          */
 558         private function getInterwikiInsertions( $existing = array() ) {
 559                 $arr = array();
 560                 foreach( $this->mInterwikis as $prefix => $dbkeys ) {
 561                         $diffs = isset( $existing[$prefix] ) ? array_diff_key( $dbkeys, $existing[$prefix] ) : $dbkeys;
 562                         foreach ( $diffs as $dbk => $id ) {
 563                                 $arr[] = array(
 564                                         'iwl_from'   => $this->mId,
 565                                         'iwl_prefix' => $prefix,
 566                                         'iwl_title'  => $dbk
 567                                 );
 568                         }
 569                 }
 570                 return $arr;
 571         }
 572
 573         /**
 574          * Given an array of existing links, returns those links which are not in $this
 575          * and thus should be deleted.
 576          * @param $existing array
 577          * @return array
 578          */
 579         private function getLinkDeletions( $existing ) {
 580                 $del = array();
 581                 foreach ( $existing as $ns => $dbkeys ) {
 582                         if ( isset( $this->mLinks[$ns] ) ) {
 583                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mLinks[$ns] );
 584                         } else {
 585                                 $del[$ns] = $existing[$ns];
 586                         }
 587                 }
 588                 return $del;
 589         }
 590
 591         /**
 592          * Given an array of existing templates, returns those templates which are not in $this
 593          * and thus should be deleted.
 594          * @param $existing array
 595          * @return array
 596          */
 597         private function getTemplateDeletions( $existing ) {
 598                 $del = array();
 599                 foreach ( $existing as $ns => $dbkeys ) {
 600                         if ( isset( $this->mTemplates[$ns] ) ) {
 601                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mTemplates[$ns] );
 602                         } else {
 603                                 $del[$ns] = $existing[$ns];
 604                         }
 605                 }
 606                 return $del;
 607         }
 608
 609         /**
 610          * Given an array of existing images, returns those images which are not in $this
 611          * and thus should be deleted.
 612          * @param $existing array
 613          * @return array
 614          */
 615         private function getImageDeletions( $existing ) {
 616                 return array_diff_key( $existing, $this->mImages );
 617         }
 618
 619         /**
 620          * Given an array of existing external links, returns those links which are not
 621          * in $this and thus should be deleted.
 622          * @param $existing array
 623          * @return array
 624          */
 625         private function getExternalDeletions( $existing ) {
 626                 return array_diff_key( $existing, $this->mExternals );
 627         }
 628
 629         /**
 630          * Given an array of existing categories, returns those categories which are not in $this
 631          * and thus should be deleted.
 632          * @param $existing array
 633          * @return array
 634          */
 635         private function getCategoryDeletions( $existing ) {
 636                 return array_diff_assoc( $existing, $this->mCategories );
 637         }
 638
 639         /**
 640          * Given an array of existing interlanguage links, returns those links which are not
 641          * in $this and thus should be deleted.
 642          * @param $existing array
 643          * @return array
 644          */
 645         private function getInterlangDeletions( $existing ) {
 646                 return array_diff_assoc( $existing, $this->mInterlangs );
 647         }
 648
 649         /**
 650          * Get array of properties which should be deleted.
 651          * @param $existing array
 652          * @return array
 653          */
 654         function getPropertyDeletions( $existing ) {
 655                 return array_diff_assoc( $existing, $this->mProperties );
 656         }
 657
 658         /**
 659          * Given an array of existing interwiki links, returns those links which are not in $this
 660          * and thus should be deleted.
 661          * @param $existing array
 662          * @return array
 663          */
 664         private function getInterwikiDeletions( $existing ) {
 665                 $del = array();
 666                 foreach ( $existing as $prefix => $dbkeys ) {
 667                         if ( isset( $this->mInterwikis[$prefix] ) ) {
 668                                 $del[$prefix] = array_diff_key( $existing[$prefix], $this->mInterwikis[$prefix] );
 669                         } else {
 670                                 $del[$prefix] = $existing[$prefix];
 671                         }
 672                 }
 673                 return $del;
 674         }
 675
 676         /**
 677          * Get an array of existing links, as a 2-D array
 678          *
 679          * @return array
 680          */
 681         private function getExistingLinks() {
 682                 $res = $this->mDb->select( 'pagelinks', array( 'pl_namespace', 'pl_title' ),
 683                         array( 'pl_from' => $this->mId ), __METHOD__, $this->mOptions );
 684                 $arr = array();
 685                 foreach ( $res as $row ) {
 686                         if ( !isset( $arr[$row->pl_namespace] ) ) {
 687                                 $arr[$row->pl_namespace] = array();
 688                         }
 689                         $arr[$row->pl_namespace][$row->pl_title] = 1;
 690                 }
 691                 return $arr;
 692         }
 693
 694         /**
 695          * Get an array of existing templates, as a 2-D array
 696          *
 697          * @return array
 698          */
 699         private function getExistingTemplates() {
 700                 $res = $this->mDb->select( 'templatelinks', array( 'tl_namespace', 'tl_title' ),
 701                         array( 'tl_from' => $this->mId ), __METHOD__, $this->mOptions );
 702                 $arr = array();
 703                 foreach ( $res as $row ) {
 704                         if ( !isset( $arr[$row->tl_namespace] ) ) {
 705                                 $arr[$row->tl_namespace] = array();
 706                         }
 707                         $arr[$row->tl_namespace][$row->tl_title] = 1;
 708                 }
 709                 return $arr;
 710         }
 711
 712         /**
 713          * Get an array of existing images, image names in the keys
 714          *
 715          * @return array
 716          */
 717         private function getExistingImages() {
 718                 $res = $this->mDb->select( 'imagelinks', array( 'il_to' ),
 719                         array( 'il_from' => $this->mId ), __METHOD__, $this->mOptions );
 720                 $arr = array();
 721                 foreach ( $res as $row ) {
 722                         $arr[$row->il_to] = 1;
 723                 }
 724                 return $arr;
 725         }
 726
 727         /**
 728          * Get an array of existing external links, URLs in the keys
 729          *
 730          * @return array
 731          */
 732         private function getExistingExternals() {
 733                 $res = $this->mDb->select( 'externallinks', array( 'el_to' ),
 734                         array( 'el_from' => $this->mId ), __METHOD__, $this->mOptions );
 735                 $arr = array();
 736                 foreach ( $res as $row ) {
 737                         $arr[$row->el_to] = 1;
 738                 }
 739                 return $arr;
 740         }
 741
 742         /**
 743          * Get an array of existing categories, with the name in the key and sort key in the value.
 744          *
 745          * @return array
 746          */
 747         private function getExistingCategories() {
 748                 $res = $this->mDb->select( 'categorylinks', array( 'cl_to', 'cl_sortkey_prefix' ),
 749                         array( 'cl_from' => $this->mId ), __METHOD__, $this->mOptions );
 750                 $arr = array();
 751                 foreach ( $res as $row ) {
 752                         $arr[$row->cl_to] = $row->cl_sortkey_prefix;
 753                 }
 754                 return $arr;
 755         }
 756
 757         /**
 758          * Get an array of existing interlanguage links, with the language code in the key and the
 759          * title in the value.
 760          *
 761          * @return array
 762          */
 763         private function getExistingInterlangs() {
 764                 $res = $this->mDb->select( 'langlinks', array( 'll_lang', 'll_title' ),
 765                         array( 'll_from' => $this->mId ), __METHOD__, $this->mOptions );
 766                 $arr = array();
 767                 foreach ( $res as $row ) {
 768                         $arr[$row->ll_lang] = $row->ll_title;
 769                 }
 770                 return $arr;
 771         }
 772
 773         /**
 774          * Get an array of existing inline interwiki links, as a 2-D array
 775          * @return array (prefix => array(dbkey => 1))
 776          */
 777         protected function getExistingInterwikis() {
 778                 $res = $this->mDb->select( 'iwlinks', array( 'iwl_prefix', 'iwl_title' ),
 779                         array( 'iwl_from' => $this->mId ), __METHOD__, $this->mOptions );
 780                 $arr = array();
 781                 foreach ( $res as $row ) {
 782                         if ( !isset( $arr[$row->iwl_prefix] ) ) {
 783                                 $arr[$row->iwl_prefix] = array();
 784                         }
 785                         $arr[$row->iwl_prefix][$row->iwl_title] = 1;
 786                 }
 787                 return $arr;
 788         }
 789
 790         /**
 791          * Get an array of existing categories, with the name in the key and sort key in the value.
 792          *
 793          * @return array
 794          */
 795         private function getExistingProperties() {
 796                 $res = $this->mDb->select( 'page_props', array( 'pp_propname', 'pp_value' ),
 797                         array( 'pp_page' => $this->mId ), __METHOD__, $this->mOptions );
 798                 $arr = array();
 799                 foreach ( $res as $row ) {
 800                         $arr[$row->pp_propname] = $row->pp_value;
 801                 }
 802                 return $arr;
 803         }
 804
 805         /**
 806          * Return the title object of the page being updated
 807          * @return Title
 808          */
 809         public function getTitle() {
 810                 return $this->mTitle;
 811         }
 812
 813         /**
 814          * Return the list of images used as generated by the parser
 815          * @return array
 816          */
 817         public function getImages() {
 818                 return $this->mImages;
 819         }
 820
 821         /**
 822          * Invalidate any necessary link lists related to page property changes
 823          * @param $changed
 824          */
 825         private function invalidateProperties( $changed ) {
 826                 global $wgPagePropLinkInvalidations;
 827
 828                 foreach ( $changed as $name => $value ) {
 829                         if ( isset( $wgPagePropLinkInvalidations[$name] ) ) {
 830                                 $inv = $wgPagePropLinkInvalidations[$name];
 831                                 if ( !is_array( $inv ) ) {
 832                                         $inv = array( $inv );
 833                                 }
 834                                 foreach ( $inv as $table ) {
 835                                         $update = new HTMLCacheUpdate( $this->mTitle, $table );
 836                                         $update->doUpdate();
 837                                 }
 838                         }
 839                 }
 840         }
 841 }