includes/deferred/LinksUpdate.php

   1 <?php
   2 /**
   3  * Updater for link tracking tables after a page edit.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * See docs/deferred.txt
  25  *
  26  * @todo document (e.g. one-sentence top-level class description).
  27  */
  28 class LinksUpdate extends SqlDataUpdate {
  29         // @todo make members protected, but make sure extensions don't break
  30
  31         public $mId, //!< Page ID of the article linked from
  32                 $mTitle, //!< Title object of the article linked from
  33                 $mParserOutput, //!< Parser output
  34                 $mLinks, //!< Map of title strings to IDs for the links in the document
  35                 $mImages, //!< DB keys of the images used, in the array key only
  36                 $mTemplates, //!< Map of title strings to IDs for the template references, including broken ones
  37                 $mExternals, //!< URLs of external links, array key only
  38                 $mCategories, //!< Map of category names to sort keys
  39                 $mInterlangs, //!< Map of language codes to titles
  40                 $mProperties, //!< Map of arbitrary name to value
  41                 $mDb, //!< Database connection reference
  42                 $mOptions, //!< SELECT options to be used (array)
  43                 $mRecursive; //!< Whether to queue jobs for recursive updates
  44
  45         /**
  46          * @var null|array Added links if calculated.
  47          */
  48         private $linkInsertions = null;
  49
  50         /**
  51          * @var null|array Deleted links if calculated.
  52          */
  53         private $linkDeletions = null;
  54
  55         /**
  56          * Constructor
  57          *
  58          * @param $title Title of the page we're updating
  59          * @param $parserOutput ParserOutput: output from a full parse of this page
  60          * @param $recursive Boolean: queue jobs for recursive updates?
  61          * @throws MWException
  62          */
  63         function __construct( $title, $parserOutput, $recursive = true ) {
  64                 parent::__construct( false ); // no implicit transaction
  65
  66                 if ( !( $title instanceof Title ) ) {
  67                         throw new MWException( "The calling convention to LinksUpdate::LinksUpdate() has changed. " .
  68                                 "Please see Article::editUpdates() for an invocation example.\n" );
  69                 }
  70
  71                 if ( !( $parserOutput instanceof ParserOutput ) ) {
  72                         throw new MWException( "The calling convention to LinksUpdate::__construct() has changed. " .
  73                                 "Please see WikiPage::doEditUpdates() for an invocation example.\n" );
  74                 }
  75
  76                 $this->mTitle = $title;
  77                 $this->mId = $title->getArticleID();
  78
  79                 if ( !$this->mId ) {
  80                         throw new MWException( "The Title object did not provide an article ID. Perhaps the page doesn't exist?" );
  81                 }
  82
  83                 $this->mParserOutput = $parserOutput;
  84
  85                 $this->mLinks = $parserOutput->getLinks();
  86                 $this->mImages = $parserOutput->getImages();
  87                 $this->mTemplates = $parserOutput->getTemplates();
  88                 $this->mExternals = $parserOutput->getExternalLinks();
  89                 $this->mCategories = $parserOutput->getCategories();
  90                 $this->mProperties = $parserOutput->getProperties();
  91                 $this->mInterwikis = $parserOutput->getInterwikiLinks();
  92
  93                 # Convert the format of the interlanguage links
  94                 # I didn't want to change it in the ParserOutput, because that array is passed all
  95                 # the way back to the skin, so either a skin API break would be required, or an
  96                 # inefficient back-conversion.
  97                 $ill = $parserOutput->getLanguageLinks();
  98                 $this->mInterlangs = array();
  99                 foreach ( $ill as $link ) {
 100                         list( $key, $title ) = explode( ':', $link, 2 );
 101                         $this->mInterlangs[$key] = $title;
 102                 }
 103
 104                 foreach ( $this->mCategories as &$sortkey ) {
 105                         # If the sortkey is longer then 255 bytes,
 106                         # it truncated by DB, and then doesn't get
 107                         # matched when comparing existing vs current
 108                         # categories, causing bug 25254.
 109                         # Also. substr behaves weird when given "".
 110                         if ( $sortkey !== '' ) {
 111                                 $sortkey = substr( $sortkey, 0, 255 );
 112                         }
 113                 }
 114
 115                 $this->mRecursive = $recursive;
 116
 117                 wfRunHooks( 'LinksUpdateConstructed', array( &$this ) );
 118         }
 119
 120         /**
 121          * Update link tables with outgoing links from an updated article
 122          */
 123         public function doUpdate() {
 124                 wfRunHooks( 'LinksUpdate', array( &$this ) );
 125                 $this->doIncrementalUpdate();
 126                 wfRunHooks( 'LinksUpdateComplete', array( &$this ) );
 127         }
 128
 129         protected function doIncrementalUpdate() {
 130                 wfProfileIn( __METHOD__ );
 131
 132                 # Page links
 133                 $existing = $this->getExistingLinks();
 134                 $this->linkDeletions = $this->getLinkDeletions( $existing );
 135                 $this->linkInsertions = $this->getLinkInsertions( $existing );
 136                 $this->incrTableUpdate( 'pagelinks', 'pl', $this->linkDeletions, $this->linkInsertions );
 137
 138                 # Image links
 139                 $existing = $this->getExistingImages();
 140
 141                 $imageDeletes = $this->getImageDeletions( $existing );
 142                 $this->incrTableUpdate( 'imagelinks', 'il', $imageDeletes,
 143                         $this->getImageInsertions( $existing ) );
 144
 145                 # Invalidate all image description pages which had links added or removed
 146                 $imageUpdates = $imageDeletes + array_diff_key( $this->mImages, $existing );
 147                 $this->invalidateImageDescriptions( $imageUpdates );
 148
 149                 # External links
 150                 $existing = $this->getExistingExternals();
 151                 $this->incrTableUpdate( 'externallinks', 'el', $this->getExternalDeletions( $existing ),
 152                         $this->getExternalInsertions( $existing ) );
 153
 154                 # Language links
 155                 $existing = $this->getExistingInterlangs();
 156                 $this->incrTableUpdate( 'langlinks', 'll', $this->getInterlangDeletions( $existing ),
 157                         $this->getInterlangInsertions( $existing ) );
 158
 159                 # Inline interwiki links
 160                 $existing = $this->getExistingInterwikis();
 161                 $this->incrTableUpdate( 'iwlinks', 'iwl', $this->getInterwikiDeletions( $existing ),
 162                         $this->getInterwikiInsertions( $existing ) );
 163
 164                 # Template links
 165                 $existing = $this->getExistingTemplates();
 166                 $this->incrTableUpdate( 'templatelinks', 'tl', $this->getTemplateDeletions( $existing ),
 167                         $this->getTemplateInsertions( $existing ) );
 168
 169                 # Category links
 170                 $existing = $this->getExistingCategories();
 171
 172                 $categoryDeletes = $this->getCategoryDeletions( $existing );
 173
 174                 $this->incrTableUpdate( 'categorylinks', 'cl', $categoryDeletes,
 175                         $this->getCategoryInsertions( $existing ) );
 176
 177                 # Invalidate all categories which were added, deleted or changed (set symmetric difference)
 178                 $categoryInserts = array_diff_assoc( $this->mCategories, $existing );
 179                 $categoryUpdates = $categoryInserts + $categoryDeletes;
 180                 $this->invalidateCategories( $categoryUpdates );
 181                 $this->updateCategoryCounts( $categoryInserts, $categoryDeletes );
 182
 183                 # Page properties
 184                 $existing = $this->getExistingProperties();
 185
 186                 $propertiesDeletes = $this->getPropertyDeletions( $existing );
 187
 188                 $this->incrTableUpdate( 'page_props', 'pp', $propertiesDeletes,
 189                         $this->getPropertyInsertions( $existing ) );
 190
 191                 # Invalidate the necessary pages
 192                 $changed = $propertiesDeletes + array_diff_assoc( $this->mProperties, $existing );
 193                 $this->invalidateProperties( $changed );
 194
 195                 # Refresh links of all pages including this page
 196                 # This will be in a separate transaction
 197                 if ( $this->mRecursive ) {
 198                         $this->queueRecursiveJobs();
 199                 }
 200
 201                 wfProfileOut( __METHOD__ );
 202         }
 203
 204         /**
 205          * Queue recursive jobs for this page
 206          *
 207          * Which means do LinksUpdate on all templates
 208          * that include the current page, using the job queue.
 209          */
 210         function queueRecursiveJobs() {
 211                 self::queueRecursiveJobsForTable( $this->mTitle, 'templatelinks' );
 212         }
 213
 214         /**
 215          * Queue a RefreshLinks job for any table.
 216          *
 217          * @param Title $title Title to do job for
 218          * @param String $table Table to use (e.g. 'templatelinks')
 219          */
 220         public static function queueRecursiveJobsForTable( Title $title, $table ) {
 221                 wfProfileIn( __METHOD__ );
 222                 if ( $title->getBacklinkCache()->hasLinks( $table ) ) {
 223                         $job = new RefreshLinksJob2(
 224                                 $title,
 225                                 array(
 226                                         'table' => $table,
 227                                 ) + Job::newRootJobParams( // "overall" refresh links job info
 228                                         "refreshlinks:{$table}:{$title->getPrefixedText()}"
 229                                 )
 230                         );
 231                         JobQueueGroup::singleton()->push( $job );
 232                         JobQueueGroup::singleton()->deduplicateRootJob( $job );
 233                 }
 234                 wfProfileOut( __METHOD__ );
 235         }
 236
 237         /**
 238          * @param $cats
 239          */
 240         function invalidateCategories( $cats ) {
 241                 $this->invalidatePages( NS_CATEGORY, array_keys( $cats ) );
 242         }
 243
 244         /**
 245          * Update all the appropriate counts in the category table.
 246          * @param array $added associative array of category name => sort key
 247          * @param array $deleted associative array of category name => sort key
 248          */
 249         function updateCategoryCounts( $added, $deleted ) {
 250                 $a = WikiPage::factory( $this->mTitle );
 251                 $a->updateCategoryCounts(
 252                         array_keys( $added ), array_keys( $deleted )
 253                 );
 254         }
 255
 256         /**
 257          * @param $images
 258          */
 259         function invalidateImageDescriptions( $images ) {
 260                 $this->invalidatePages( NS_FILE, array_keys( $images ) );
 261         }
 262
 263         /**
 264          * Update a table by doing a delete query then an insert query
 265          * @param $table
 266          * @param $prefix
 267          * @param $deletions
 268          * @param $insertions
 269          */
 270         function incrTableUpdate( $table, $prefix, $deletions, $insertions ) {
 271                 if ( $table == 'page_props' ) {
 272                         $fromField = 'pp_page';
 273                 } else {
 274                         $fromField = "{$prefix}_from";
 275                 }
 276                 $where = array( $fromField => $this->mId );
 277                 if ( $table == 'pagelinks' || $table == 'templatelinks' || $table == 'iwlinks' ) {
 278                         if ( $table == 'iwlinks' ) {
 279                                 $baseKey = 'iwl_prefix';
 280                         } else {
 281                                 $baseKey = "{$prefix}_namespace";
 282                         }
 283                         $clause = $this->mDb->makeWhereFrom2d( $deletions, $baseKey, "{$prefix}_title" );
 284                         if ( $clause ) {
 285                                 $where[] = $clause;
 286                         } else {
 287                                 $where = false;
 288                         }
 289                 } else {
 290                         if ( $table == 'langlinks' ) {
 291                                 $toField = 'll_lang';
 292                         } elseif ( $table == 'page_props' ) {
 293                                 $toField = 'pp_propname';
 294                         } else {
 295                                 $toField = $prefix . '_to';
 296                         }
 297                         if ( count( $deletions ) ) {
 298                                 $where[] = "$toField IN (" . $this->mDb->makeList( array_keys( $deletions ) ) . ')';
 299                         } else {
 300                                 $where = false;
 301                         }
 302                 }
 303                 if ( $where ) {
 304                         $this->mDb->delete( $table, $where, __METHOD__ );
 305                 }
 306                 if ( count( $insertions ) ) {
 307                         $this->mDb->insert( $table, $insertions, __METHOD__, 'IGNORE' );
 308                         wfRunHooks( 'LinksUpdateAfterInsert', array( $this, $table, $insertions ) );
 309                 }
 310         }
 311
 312         /**
 313          * Get an array of pagelinks insertions for passing to the DB
 314          * Skips the titles specified by the 2-D array $existing
 315          * @param $existing array
 316          * @return array
 317          */
 318         private function getLinkInsertions( $existing = array() ) {
 319                 $arr = array();
 320                 foreach ( $this->mLinks as $ns => $dbkeys ) {
 321                         $diffs = isset( $existing[$ns] )
 322                                 ? array_diff_key( $dbkeys, $existing[$ns] )
 323                                 : $dbkeys;
 324                         foreach ( $diffs as $dbk => $id ) {
 325                                 $arr[] = array(
 326                                         'pl_from' => $this->mId,
 327                                         'pl_namespace' => $ns,
 328                                         'pl_title' => $dbk
 329                                 );
 330                         }
 331                 }
 332
 333                 return $arr;
 334         }
 335
 336         /**
 337          * Get an array of template insertions. Like getLinkInsertions()
 338          * @param $existing array
 339          * @return array
 340          */
 341         private function getTemplateInsertions( $existing = array() ) {
 342                 $arr = array();
 343                 foreach ( $this->mTemplates as $ns => $dbkeys ) {
 344                         $diffs = isset( $existing[$ns] ) ? array_diff_key( $dbkeys, $existing[$ns] ) : $dbkeys;
 345                         foreach ( $diffs as $dbk => $id ) {
 346                                 $arr[] = array(
 347                                         'tl_from' => $this->mId,
 348                                         'tl_namespace' => $ns,
 349                                         'tl_title' => $dbk
 350                                 );
 351                         }
 352                 }
 353
 354                 return $arr;
 355         }
 356
 357         /**
 358          * Get an array of image insertions
 359          * Skips the names specified in $existing
 360          * @param $existing array
 361          * @return array
 362          */
 363         private function getImageInsertions( $existing = array() ) {
 364                 $arr = array();
 365                 $diffs = array_diff_key( $this->mImages, $existing );
 366                 foreach ( $diffs as $iname => $dummy ) {
 367                         $arr[] = array(
 368                                 'il_from' => $this->mId,
 369                                 'il_to' => $iname
 370                         );
 371                 }
 372
 373                 return $arr;
 374         }
 375
 376         /**
 377          * Get an array of externallinks insertions. Skips the names specified in $existing
 378          * @param $existing array
 379          * @return array
 380          */
 381         private function getExternalInsertions( $existing = array() ) {
 382                 $arr = array();
 383                 $diffs = array_diff_key( $this->mExternals, $existing );
 384                 foreach ( $diffs as $url => $dummy ) {
 385                         foreach ( wfMakeUrlIndexes( $url ) as $index ) {
 386                                 $arr[] = array(
 387                                         'el_from' => $this->mId,
 388                                         'el_to' => $url,
 389                                         'el_index' => $index,
 390                                 );
 391                         }
 392                 }
 393
 394                 return $arr;
 395         }
 396
 397         /**
 398          * Get an array of category insertions
 399          *
 400          * @param array $existing mapping existing category names to sort keys. If both
 401          * match a link in $this, the link will be omitted from the output
 402          *
 403          * @return array
 404          */
 405         private function getCategoryInsertions( $existing = array() ) {
 406                 global $wgContLang, $wgCategoryCollation;
 407                 $diffs = array_diff_assoc( $this->mCategories, $existing );
 408                 $arr = array();
 409                 foreach ( $diffs as $name => $prefix ) {
 410                         $nt = Title::makeTitleSafe( NS_CATEGORY, $name );
 411                         $wgContLang->findVariantLink( $name, $nt, true );
 412
 413                         if ( $this->mTitle->getNamespace() == NS_CATEGORY ) {
 414                                 $type = 'subcat';
 415                         } elseif ( $this->mTitle->getNamespace() == NS_FILE ) {
 416                                 $type = 'file';
 417                         } else {
 418                                 $type = 'page';
 419                         }
 420
 421                         # Treat custom sortkeys as a prefix, so that if multiple
 422                         # things are forced to sort as '*' or something, they'll
 423                         # sort properly in the category rather than in page_id
 424                         # order or such.
 425                         $sortkey = Collation::singleton()->getSortKey(
 426                                 $this->mTitle->getCategorySortkey( $prefix ) );
 427
 428                         $arr[] = array(
 429                                 'cl_from' => $this->mId,
 430                                 'cl_to' => $name,
 431                                 'cl_sortkey' => $sortkey,
 432                                 'cl_timestamp' => $this->mDb->timestamp(),
 433                                 'cl_sortkey_prefix' => $prefix,
 434                                 'cl_collation' => $wgCategoryCollation,
 435                                 'cl_type' => $type,
 436                         );
 437                 }
 438
 439                 return $arr;
 440         }
 441
 442         /**
 443          * Get an array of interlanguage link insertions
 444          *
 445          * @param array $existing mapping existing language codes to titles
 446          *
 447          * @return array
 448          */
 449         private function getInterlangInsertions( $existing = array() ) {
 450                 $diffs = array_diff_assoc( $this->mInterlangs, $existing );
 451                 $arr = array();
 452                 foreach ( $diffs as $lang => $title ) {
 453                         $arr[] = array(
 454                                 'll_from' => $this->mId,
 455                                 'll_lang' => $lang,
 456                                 'll_title' => $title
 457                         );
 458                 }
 459
 460                 return $arr;
 461         }
 462
 463         /**
 464          * Get an array of page property insertions
 465          * @param $existing array
 466          * @return array
 467          */
 468         function getPropertyInsertions( $existing = array() ) {
 469                 $diffs = array_diff_assoc( $this->mProperties, $existing );
 470                 $arr = array();
 471                 foreach ( $diffs as $name => $value ) {
 472                         $arr[] = array(
 473                                 'pp_page' => $this->mId,
 474                                 'pp_propname' => $name,
 475                                 'pp_value' => $value,
 476                         );
 477                 }
 478
 479                 return $arr;
 480         }
 481
 482         /**
 483          * Get an array of interwiki insertions for passing to the DB
 484          * Skips the titles specified by the 2-D array $existing
 485          * @param $existing array
 486          * @return array
 487          */
 488         private function getInterwikiInsertions( $existing = array() ) {
 489                 $arr = array();
 490                 foreach ( $this->mInterwikis as $prefix => $dbkeys ) {
 491                         $diffs = isset( $existing[$prefix] ) ? array_diff_key( $dbkeys, $existing[$prefix] ) : $dbkeys;
 492                         foreach ( $diffs as $dbk => $id ) {
 493                                 $arr[] = array(
 494                                         'iwl_from' => $this->mId,
 495                                         'iwl_prefix' => $prefix,
 496                                         'iwl_title' => $dbk
 497                                 );
 498                         }
 499                 }
 500
 501                 return $arr;
 502         }
 503
 504         /**
 505          * Given an array of existing links, returns those links which are not in $this
 506          * and thus should be deleted.
 507          * @param $existing array
 508          * @return array
 509          */
 510         private function getLinkDeletions( $existing ) {
 511                 $del = array();
 512                 foreach ( $existing as $ns => $dbkeys ) {
 513                         if ( isset( $this->mLinks[$ns] ) ) {
 514                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mLinks[$ns] );
 515                         } else {
 516                                 $del[$ns] = $existing[$ns];
 517                         }
 518                 }
 519
 520                 return $del;
 521         }
 522
 523         /**
 524          * Given an array of existing templates, returns those templates which are not in $this
 525          * and thus should be deleted.
 526          * @param $existing array
 527          * @return array
 528          */
 529         private function getTemplateDeletions( $existing ) {
 530                 $del = array();
 531                 foreach ( $existing as $ns => $dbkeys ) {
 532                         if ( isset( $this->mTemplates[$ns] ) ) {
 533                                 $del[$ns] = array_diff_key( $existing[$ns], $this->mTemplates[$ns] );
 534                         } else {
 535                                 $del[$ns] = $existing[$ns];
 536                         }
 537                 }
 538
 539                 return $del;
 540         }
 541
 542         /**
 543          * Given an array of existing images, returns those images which are not in $this
 544          * and thus should be deleted.
 545          * @param $existing array
 546          * @return array
 547          */
 548         private function getImageDeletions( $existing ) {
 549                 return array_diff_key( $existing, $this->mImages );
 550         }
 551
 552         /**
 553          * Given an array of existing external links, returns those links which are not
 554          * in $this and thus should be deleted.
 555          * @param $existing array
 556          * @return array
 557          */
 558         private function getExternalDeletions( $existing ) {
 559                 return array_diff_key( $existing, $this->mExternals );
 560         }
 561
 562         /**
 563          * Given an array of existing categories, returns those categories which are not in $this
 564          * and thus should be deleted.
 565          * @param $existing array
 566          * @return array
 567          */
 568         private function getCategoryDeletions( $existing ) {
 569                 return array_diff_assoc( $existing, $this->mCategories );
 570         }
 571
 572         /**
 573          * Given an array of existing interlanguage links, returns those links which are not
 574          * in $this and thus should be deleted.
 575          * @param $existing array
 576          * @return array
 577          */
 578         private function getInterlangDeletions( $existing ) {
 579                 return array_diff_assoc( $existing, $this->mInterlangs );
 580         }
 581
 582         /**
 583          * Get array of properties which should be deleted.
 584          * @param $existing array
 585          * @return array
 586          */
 587         function getPropertyDeletions( $existing ) {
 588                 return array_diff_assoc( $existing, $this->mProperties );
 589         }
 590
 591         /**
 592          * Given an array of existing interwiki links, returns those links which are not in $this
 593          * and thus should be deleted.
 594          * @param $existing array
 595          * @return array
 596          */
 597         private function getInterwikiDeletions( $existing ) {
 598                 $del = array();
 599                 foreach ( $existing as $prefix => $dbkeys ) {
 600                         if ( isset( $this->mInterwikis[$prefix] ) ) {
 601                                 $del[$prefix] = array_diff_key( $existing[$prefix], $this->mInterwikis[$prefix] );
 602                         } else {
 603                                 $del[$prefix] = $existing[$prefix];
 604                         }
 605                 }
 606
 607                 return $del;
 608         }
 609
 610         /**
 611          * Get an array of existing links, as a 2-D array
 612          *
 613          * @return array
 614          */
 615         private function getExistingLinks() {
 616                 $res = $this->mDb->select( 'pagelinks', array( 'pl_namespace', 'pl_title' ),
 617                         array( 'pl_from' => $this->mId ), __METHOD__, $this->mOptions );
 618                 $arr = array();
 619                 foreach ( $res as $row ) {
 620                         if ( !isset( $arr[$row->pl_namespace] ) ) {
 621                                 $arr[$row->pl_namespace] = array();
 622                         }
 623                         $arr[$row->pl_namespace][$row->pl_title] = 1;
 624                 }
 625
 626                 return $arr;
 627         }
 628
 629         /**
 630          * Get an array of existing templates, as a 2-D array
 631          *
 632          * @return array
 633          */
 634         private function getExistingTemplates() {
 635                 $res = $this->mDb->select( 'templatelinks', array( 'tl_namespace', 'tl_title' ),
 636                         array( 'tl_from' => $this->mId ), __METHOD__, $this->mOptions );
 637                 $arr = array();
 638                 foreach ( $res as $row ) {
 639                         if ( !isset( $arr[$row->tl_namespace] ) ) {
 640                                 $arr[$row->tl_namespace] = array();
 641                         }
 642                         $arr[$row->tl_namespace][$row->tl_title] = 1;
 643                 }
 644
 645                 return $arr;
 646         }
 647
 648         /**
 649          * Get an array of existing images, image names in the keys
 650          *
 651          * @return array
 652          */
 653         private function getExistingImages() {
 654                 $res = $this->mDb->select( 'imagelinks', array( 'il_to' ),
 655                         array( 'il_from' => $this->mId ), __METHOD__, $this->mOptions );
 656                 $arr = array();
 657                 foreach ( $res as $row ) {
 658                         $arr[$row->il_to] = 1;
 659                 }
 660
 661                 return $arr;
 662         }
 663
 664         /**
 665          * Get an array of existing external links, URLs in the keys
 666          *
 667          * @return array
 668          */
 669         private function getExistingExternals() {
 670                 $res = $this->mDb->select( 'externallinks', array( 'el_to' ),
 671                         array( 'el_from' => $this->mId ), __METHOD__, $this->mOptions );
 672                 $arr = array();
 673                 foreach ( $res as $row ) {
 674                         $arr[$row->el_to] = 1;
 675                 }
 676
 677                 return $arr;
 678         }
 679
 680         /**
 681          * Get an array of existing categories, with the name in the key and sort key in the value.
 682          *
 683          * @return array
 684          */
 685         private function getExistingCategories() {
 686                 $res = $this->mDb->select( 'categorylinks', array( 'cl_to', 'cl_sortkey_prefix' ),
 687                         array( 'cl_from' => $this->mId ), __METHOD__, $this->mOptions );
 688                 $arr = array();
 689                 foreach ( $res as $row ) {
 690                         $arr[$row->cl_to] = $row->cl_sortkey_prefix;
 691                 }
 692
 693                 return $arr;
 694         }
 695
 696         /**
 697          * Get an array of existing interlanguage links, with the language code in the key and the
 698          * title in the value.
 699          *
 700          * @return array
 701          */
 702         private function getExistingInterlangs() {
 703                 $res = $this->mDb->select( 'langlinks', array( 'll_lang', 'll_title' ),
 704                         array( 'll_from' => $this->mId ), __METHOD__, $this->mOptions );
 705                 $arr = array();
 706                 foreach ( $res as $row ) {
 707                         $arr[$row->ll_lang] = $row->ll_title;
 708                 }
 709
 710                 return $arr;
 711         }
 712
 713         /**
 714          * Get an array of existing inline interwiki links, as a 2-D array
 715          * @return array (prefix => array(dbkey => 1))
 716          */
 717         protected function getExistingInterwikis() {
 718                 $res = $this->mDb->select( 'iwlinks', array( 'iwl_prefix', 'iwl_title' ),
 719                         array( 'iwl_from' => $this->mId ), __METHOD__, $this->mOptions );
 720                 $arr = array();
 721                 foreach ( $res as $row ) {
 722                         if ( !isset( $arr[$row->iwl_prefix] ) ) {
 723                                 $arr[$row->iwl_prefix] = array();
 724                         }
 725                         $arr[$row->iwl_prefix][$row->iwl_title] = 1;
 726                 }
 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          *
 734          * @return array
 735          */
 736         private function getExistingProperties() {
 737                 $res = $this->mDb->select( 'page_props', array( 'pp_propname', 'pp_value' ),
 738                         array( 'pp_page' => $this->mId ), __METHOD__, $this->mOptions );
 739                 $arr = array();
 740                 foreach ( $res as $row ) {
 741                         $arr[$row->pp_propname] = $row->pp_value;
 742                 }
 743
 744                 return $arr;
 745         }
 746
 747         /**
 748          * Return the title object of the page being updated
 749          * @return Title
 750          */
 751         public function getTitle() {
 752                 return $this->mTitle;
 753         }
 754
 755         /**
 756          * Returns parser output
 757          * @since 1.19
 758          * @return ParserOutput
 759          */
 760         public function getParserOutput() {
 761                 return $this->mParserOutput;
 762         }
 763
 764         /**
 765          * Return the list of images used as generated by the parser
 766          * @return array
 767          */
 768         public function getImages() {
 769                 return $this->mImages;
 770         }
 771
 772         /**
 773          * Invalidate any necessary link lists related to page property changes
 774          * @param $changed
 775          */
 776         private function invalidateProperties( $changed ) {
 777                 global $wgPagePropLinkInvalidations;
 778
 779                 foreach ( $changed as $name => $value ) {
 780                         if ( isset( $wgPagePropLinkInvalidations[$name] ) ) {
 781                                 $inv = $wgPagePropLinkInvalidations[$name];
 782                                 if ( !is_array( $inv ) ) {
 783                                         $inv = array( $inv );
 784                                 }
 785                                 foreach ( $inv as $table ) {
 786                                         $update = new HTMLCacheUpdate( $this->mTitle, $table );
 787                                         $update->doUpdate();
 788                                 }
 789                         }
 790                 }
 791         }
 792
 793         /**
 794          * Fetch page links added by this LinksUpdate.  Only available after the update is complete.
 795          * @since 1.22
 796          * @return null|array of Titles
 797          */
 798         public function getAddedLinks() {
 799                 if ( $this->linkInsertions === null ) {
 800                         return null;
 801                 }
 802                 $result = array();
 803                 foreach ( $this->linkInsertions as $insertion ) {
 804                         $result[] = Title::makeTitle( $insertion['pl_namespace'], $insertion['pl_title'] );
 805                 }
 806
 807                 return $result;
 808         }
 809
 810         /**
 811          * Fetch page links removed by this LinksUpdate.  Only available after the update is complete.
 812          * @since 1.22
 813          * @return null|array of Titles
 814          */
 815         public function getRemovedLinks() {
 816                 if ( $this->linkDeletions === null ) {
 817                         return null;
 818                 }
 819                 $result = array();
 820                 foreach ( $this->linkDeletions as $ns => $titles ) {
 821                         foreach ( $titles as $title => $unused ) {
 822                                 $result[] = Title::makeTitle( $ns, $title );
 823                         }
 824                 }
 825
 826                 return $result;
 827         }
 828 }
 829
 830 /**
 831  * Update object handling the cleanup of links tables after a page was deleted.
 832  **/
 833 class LinksDeletionUpdate extends SqlDataUpdate {
 834         protected $mPage; //!< WikiPage the wikipage that was deleted
 835
 836         /**
 837          * Constructor
 838          *
 839          * @param $page WikiPage Page we are updating
 840          * @throws MWException
 841          */
 842         function __construct( WikiPage $page ) {
 843                 parent::__construct( false ); // no implicit transaction
 844
 845                 $this->mPage = $page;
 846
 847                 if ( !$page->exists() ) {
 848                         throw new MWException( "Page ID not known, perhaps the page doesn't exist?" );
 849                 }
 850         }
 851
 852         /**
 853          * Do some database updates after deletion
 854          */
 855         public function doUpdate() {
 856                 $title = $this->mPage->getTitle();
 857                 $id = $this->mPage->getId();
 858
 859                 # Delete restrictions for it
 860                 $this->mDb->delete( 'page_restrictions', array( 'pr_page' => $id ), __METHOD__ );
 861
 862                 # Fix category table counts
 863                 $cats = array();
 864                 $res = $this->mDb->select( 'categorylinks', 'cl_to', array( 'cl_from' => $id ), __METHOD__ );
 865
 866                 foreach ( $res as $row ) {
 867                         $cats[] = $row->cl_to;
 868                 }
 869
 870                 $this->mPage->updateCategoryCounts( array(), $cats );
 871
 872                 # If using cascading deletes, we can skip some explicit deletes
 873                 if ( !$this->mDb->cascadingDeletes() ) {
 874                         # Delete outgoing links
 875                         $this->mDb->delete( 'pagelinks', array( 'pl_from' => $id ), __METHOD__ );
 876                         $this->mDb->delete( 'imagelinks', array( 'il_from' => $id ), __METHOD__ );
 877                         $this->mDb->delete( 'categorylinks', array( 'cl_from' => $id ), __METHOD__ );
 878                         $this->mDb->delete( 'templatelinks', array( 'tl_from' => $id ), __METHOD__ );
 879                         $this->mDb->delete( 'externallinks', array( 'el_from' => $id ), __METHOD__ );
 880                         $this->mDb->delete( 'langlinks', array( 'll_from' => $id ), __METHOD__ );
 881                         $this->mDb->delete( 'iwlinks', array( 'iwl_from' => $id ), __METHOD__ );
 882                         $this->mDb->delete( 'redirect', array( 'rd_from' => $id ), __METHOD__ );
 883                         $this->mDb->delete( 'page_props', array( 'pp_page' => $id ), __METHOD__ );
 884                 }
 885
 886                 # If using cleanup triggers, we can skip some manual deletes
 887                 if ( !$this->mDb->cleanupTriggers() ) {
 888                         # Clean up recentchanges entries...
 889                         $this->mDb->delete( 'recentchanges',
 890                                 array( 'rc_type != ' . RC_LOG,
 891                                         'rc_namespace' => $title->getNamespace(),
 892                                         'rc_title' => $title->getDBkey() ),
 893                                 __METHOD__ );
 894                         $this->mDb->delete( 'recentchanges',
 895                                 array( 'rc_type != ' . RC_LOG, 'rc_cur_id' => $id ),
 896                                 __METHOD__ );
 897                 }
 898         }
 899
 900         /**
 901          * Update all the appropriate counts in the category table.
 902          * @param array $added associative array of category name => sort key
 903          * @param array $deleted associative array of category name => sort key
 904          */
 905         function updateCategoryCounts( $added, $deleted ) {
 906                 $a = WikiPage::factory( $this->mTitle );
 907                 $a->updateCategoryCounts(
 908                         array_keys( $added ), array_keys( $deleted )
 909                 );
 910         }
 911 }