includes/QueryPage.php

   1 <?php
   2 /**
   3  * Base code for "query" special pages.
   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  * @ingroup SpecialPage
  22  */
  23
  24 /**
  25  * This is a class for doing query pages; since they're almost all the same,
  26  * we factor out some of the functionality into a superclass, and let
  27  * subclasses derive from it.
  28  * @ingroup SpecialPage
  29  */
  30 abstract class QueryPage extends SpecialPage {
  31         /** @var bool Whether or not we want plain listoutput rather than an ordered list */
  32         protected $listoutput = false;
  33
  34         /** @var int The offset and limit in use, as passed to the query() function */
  35         protected $offset = 0;
  36
  37         /** @var int */
  38         protected $limit = 0;
  39
  40         /**
  41          * The number of rows returned by the query. Reading this variable
  42          * only makes sense in functions that are run after the query has been
  43          * done, such as preprocessResults() and formatRow().
  44          */
  45         protected $numRows;
  46
  47         protected $cachedTimestamp = null;
  48
  49         /**
  50          * Whether to show prev/next links
  51          */
  52         protected $shownavigation = true;
  53
  54         /**
  55          * Get a list of query page classes and their associated special pages,
  56          * for periodic updates.
  57          *
  58          * DO NOT CHANGE THIS LIST without testing that
  59          * maintenance/updateSpecialPages.php still works.
  60          * @return array
  61          */
  62         public static function getPages() {
  63                 global $wgDisableCounters;
  64                 static $qp = null;
  65
  66                 if ( $qp === null ) {
  67                         // QueryPage subclass, Special page name
  68                         $qp = array(
  69                                 array( 'AncientPagesPage', 'Ancientpages' ),
  70                                 array( 'BrokenRedirectsPage', 'BrokenRedirects' ),
  71                                 array( 'DeadendPagesPage', 'Deadendpages' ),
  72                                 array( 'DoubleRedirectsPage', 'DoubleRedirects' ),
  73                                 array( 'FileDuplicateSearchPage', 'FileDuplicateSearch' ),
  74                                 array( 'ListDuplicatedFilesPage', 'ListDuplicatedFiles'),
  75                                 array( 'LinkSearchPage', 'LinkSearch' ),
  76                                 array( 'ListredirectsPage', 'Listredirects' ),
  77                                 array( 'LonelyPagesPage', 'Lonelypages' ),
  78                                 array( 'LongPagesPage', 'Longpages' ),
  79                                 array( 'MIMEsearchPage', 'MIMEsearch' ),
  80                                 array( 'MostcategoriesPage', 'Mostcategories' ),
  81                                 array( 'MostimagesPage', 'Mostimages' ),
  82                                 array( 'MostinterwikisPage', 'Mostinterwikis' ),
  83                                 array( 'MostlinkedCategoriesPage', 'Mostlinkedcategories' ),
  84                                 array( 'MostlinkedtemplatesPage', 'Mostlinkedtemplates' ),
  85                                 array( 'MostlinkedPage', 'Mostlinked' ),
  86                                 array( 'MostrevisionsPage', 'Mostrevisions' ),
  87                                 array( 'FewestrevisionsPage', 'Fewestrevisions' ),
  88                                 array( 'ShortPagesPage', 'Shortpages' ),
  89                                 array( 'UncategorizedCategoriesPage', 'Uncategorizedcategories' ),
  90                                 array( 'UncategorizedPagesPage', 'Uncategorizedpages' ),
  91                                 array( 'UncategorizedImagesPage', 'Uncategorizedimages' ),
  92                                 array( 'UncategorizedTemplatesPage', 'Uncategorizedtemplates' ),
  93                                 array( 'UnusedCategoriesPage', 'Unusedcategories' ),
  94                                 array( 'UnusedimagesPage', 'Unusedimages' ),
  95                                 array( 'WantedCategoriesPage', 'Wantedcategories' ),
  96                                 array( 'WantedFilesPage', 'Wantedfiles' ),
  97                                 array( 'WantedPagesPage', 'Wantedpages' ),
  98                                 array( 'WantedTemplatesPage', 'Wantedtemplates' ),
  99                                 array( 'UnwatchedPagesPage', 'Unwatchedpages' ),
 100                                 array( 'UnusedtemplatesPage', 'Unusedtemplates' ),
 101                                 array( 'WithoutInterwikiPage', 'Withoutinterwiki' ),
 102                         );
 103                         wfRunHooks( 'wgQueryPages', array( &$qp ) );
 104
 105                         if ( !$wgDisableCounters ) {
 106                                 $qp[] = array( 'PopularPagesPage', 'Popularpages' );
 107                         }
 108                 }
 109
 110                 return $qp;
 111         }
 112
 113         /**
 114          * A mutator for $this->listoutput;
 115          *
 116          * @param bool $bool
 117          */
 118         function setListoutput( $bool ) {
 119                 $this->listoutput = $bool;
 120         }
 121
 122         /**
 123          * Subclasses return an SQL query here, formatted as an array with the
 124          * following keys:
 125          *    tables => Table(s) for passing to Database::select()
 126          *    fields => Field(s) for passing to Database::select(), may be *
 127          *    conds => WHERE conditions
 128          *    options => options
 129          *    join_conds => JOIN conditions
 130          *
 131          * Note that the query itself should return the following three columns:
 132          * 'namespace', 'title', and 'value'. 'value' is used for sorting.
 133          *
 134          * These may be stored in the querycache table for expensive queries,
 135          * and that cached data will be returned sometimes, so the presence of
 136          * extra fields can't be relied upon. The cached 'value' column will be
 137          * an integer; non-numeric values are useful only for sorting the
 138          * initial query (except if they're timestamps, see usesTimestamps()).
 139          *
 140          * Don't include an ORDER or LIMIT clause, they will be added.
 141          *
 142          * If this function is not overridden or returns something other than
 143          * an array, getSQL() will be used instead. This is for backwards
 144          * compatibility only and is strongly deprecated.
 145          * @return array
 146          * @since 1.18
 147          */
 148         function getQueryInfo() {
 149                 return null;
 150         }
 151
 152         /**
 153          * For back-compat, subclasses may return a raw SQL query here, as a string.
 154          * This is strongly deprecated; getQueryInfo() should be overridden instead.
 155          * @throws MWException
 156          * @return string
 157          */
 158         function getSQL() {
 159                 /* Implement getQueryInfo() instead */
 160                 throw new MWException( "Bug in a QueryPage: doesn't implement getQueryInfo() nor "
 161                         . "getQuery() properly" );
 162         }
 163
 164         /**
 165          * Subclasses return an array of fields to order by here. Don't append
 166          * DESC to the field names, that'll be done automatically if
 167          * sortDescending() returns true.
 168          * @return array
 169          * @since 1.18
 170          */
 171         function getOrderFields() {
 172                 return array( 'value' );
 173         }
 174
 175         /**
 176          * Does this query return timestamps rather than integers in its
 177          * 'value' field? If true, this class will convert 'value' to a
 178          * UNIX timestamp for caching.
 179          * NOTE: formatRow() may get timestamps in TS_MW (mysql), TS_DB (pgsql)
 180          *       or TS_UNIX (querycache) format, so be sure to always run them
 181          *       through wfTimestamp()
 182          * @return bool
 183          * @since 1.18
 184          */
 185         function usesTimestamps() {
 186                 return false;
 187         }
 188
 189         /**
 190          * Override to sort by increasing values
 191          *
 192          * @return bool
 193          */
 194         function sortDescending() {
 195                 return true;
 196         }
 197
 198         /**
 199          * Is this query expensive (for some definition of expensive)? Then we
 200          * don't let it run in miser mode. $wgDisableQueryPages causes all query
 201          * pages to be declared expensive. Some query pages are always expensive.
 202          *
 203          * @return bool
 204          */
 205         function isExpensive() {
 206                 global $wgDisableQueryPages;
 207                 return $wgDisableQueryPages;
 208         }
 209
 210         /**
 211          * Is the output of this query cacheable? Non-cacheable expensive pages
 212          * will be disabled in miser mode and will not have their results written
 213          * to the querycache table.
 214          * @return bool
 215          * @since 1.18
 216          */
 217         public function isCacheable() {
 218                 return true;
 219         }
 220
 221         /**
 222          * Whether or not the output of the page in question is retrieved from
 223          * the database cache.
 224          *
 225          * @return bool
 226          */
 227         function isCached() {
 228                 global $wgMiserMode;
 229
 230                 return $this->isExpensive() && $wgMiserMode;
 231         }
 232
 233         /**
 234          * Sometime we don't want to build rss / atom feeds.
 235          *
 236          * @return bool
 237          */
 238         function isSyndicated() {
 239                 return true;
 240         }
 241
 242         /**
 243          * Formats the results of the query for display. The skin is the current
 244          * skin; you can use it for making links. The result is a single row of
 245          * result data. You should be able to grab SQL results off of it.
 246          * If the function returns false, the line output will be skipped.
 247          * @param Skin $skin
 248          * @param object $result Result row
 249          * @return string|bool String or false to skip
 250          */
 251         abstract function formatResult( $skin, $result );
 252
 253         /**
 254          * The content returned by this function will be output before any result
 255          *
 256          * @return string
 257          */
 258         function getPageHeader() {
 259                 return '';
 260         }
 261
 262         /**
 263          * If using extra form wheely-dealies, return a set of parameters here
 264          * as an associative array. They will be encoded and added to the paging
 265          * links (prev/next/lengths).
 266          *
 267          * @return array
 268          */
 269         function linkParameters() {
 270                 return array();
 271         }
 272
 273         /**
 274          * Some special pages (for example SpecialListusers) might not return the
 275          * current object formatted, but return the previous one instead.
 276          * Setting this to return true will ensure formatResult() is called
 277          * one more time to make sure that the very last result is formatted
 278          * as well.
 279          * @return bool
 280          */
 281         function tryLastResult() {
 282                 return false;
 283         }
 284
 285         /**
 286          * Clear the cache and save new results
 287          *
 288          * @param int|bool $limit Limit for SQL statement
 289          * @param bool $ignoreErrors Whether to ignore database errors
 290          * @throws DBError|Exception
 291          * @return bool|int
 292          */
 293         function recache( $limit, $ignoreErrors = true ) {
 294                 if ( !$this->isCacheable() ) {
 295                         return 0;
 296                 }
 297
 298                 $fname = get_class( $this ) . '::recache';
 299                 $dbw = wfGetDB( DB_MASTER );
 300                 if ( !$dbw ) {
 301                         return false;
 302                 }
 303
 304                 try {
 305                         # Do query
 306                         $res = $this->reallyDoQuery( $limit, false );
 307                         $num = false;
 308                         if ( $res ) {
 309                                 $num = $res->numRows();
 310                                 # Fetch results
 311                                 $vals = array();
 312                                 foreach ( $res as $row ) {
 313                                         if ( isset( $row->value ) ) {
 314                                                 if ( $this->usesTimestamps() ) {
 315                                                         $value = wfTimestamp( TS_UNIX,
 316                                                                 $row->value );
 317                                                 } else {
 318                                                         $value = intval( $row->value ); // @bug 14414
 319                                                 }
 320                                         } else {
 321                                                 $value = 0;
 322                                         }
 323
 324                                         $vals[] = array( 'qc_type' => $this->getName(),
 325                                                         'qc_namespace' => $row->namespace,
 326                                                         'qc_title' => $row->title,
 327                                                         'qc_value' => $value );
 328                                 }
 329
 330                                 $dbw->begin( __METHOD__ );
 331                                 # Clear out any old cached data
 332                                 $dbw->delete( 'querycache', array( 'qc_type' => $this->getName() ), $fname );
 333                                 # Save results into the querycache table on the master
 334                                 if ( count( $vals ) ) {
 335                                         $dbw->insert( 'querycache', $vals, __METHOD__ );
 336                                 }
 337                                 # Update the querycache_info record for the page
 338                                 $dbw->delete( 'querycache_info', array( 'qci_type' => $this->getName() ), $fname );
 339                                 $dbw->insert( 'querycache_info',
 340                                         array( 'qci_type' => $this->getName(), 'qci_timestamp' => $dbw->timestamp() ),
 341                                         $fname );
 342                                 $dbw->commit( __METHOD__ );
 343                         }
 344                 } catch ( DBError $e ) {
 345                         if ( !$ignoreErrors ) {
 346                                 throw $e; // report query error
 347                         }
 348                         $num = false; // set result to false to indicate error
 349                 }
 350
 351                 return $num;
 352         }
 353
 354         /**
 355          * Get a DB connection to be used for slow recache queries
 356          * @return DatabaseBase
 357          */
 358         function getRecacheDB() {
 359                 return wfGetDB( DB_SLAVE, array( $this->getName(), 'QueryPage::recache', 'vslow' ) );
 360         }
 361
 362         /**
 363          * Run the query and return the result
 364          * @param int|bool $limit Numerical limit or false for no limit
 365          * @param int|bool $offset Numerical offset or false for no offset
 366          * @return ResultWrapper
 367          * @since 1.18
 368          */
 369         function reallyDoQuery( $limit, $offset = false ) {
 370                 $fname = get_class( $this ) . "::reallyDoQuery";
 371                 $dbr = $this->getRecacheDB();
 372                 $query = $this->getQueryInfo();
 373                 $order = $this->getOrderFields();
 374
 375                 if ( $this->sortDescending() ) {
 376                         foreach ( $order as &$field ) {
 377                                 $field .= ' DESC';
 378                         }
 379                 }
 380
 381                 if ( is_array( $query ) ) {
 382                         $tables = isset( $query['tables'] ) ? (array)$query['tables'] : array();
 383                         $fields = isset( $query['fields'] ) ? (array)$query['fields'] : array();
 384                         $conds = isset( $query['conds'] ) ? (array)$query['conds'] : array();
 385                         $options = isset( $query['options'] ) ? (array)$query['options'] : array();
 386                         $join_conds = isset( $query['join_conds'] ) ? (array)$query['join_conds'] : array();
 387
 388                         if ( count( $order ) ) {
 389                                 $options['ORDER BY'] = $order;
 390                         }
 391
 392                         if ( $limit !== false ) {
 393                                 $options['LIMIT'] = intval( $limit );
 394                         }
 395
 396                         if ( $offset !== false ) {
 397                                 $options['OFFSET'] = intval( $offset );
 398                         }
 399
 400                         $res = $dbr->select( $tables, $fields, $conds, $fname,
 401                                         $options, $join_conds
 402                         );
 403                 } else {
 404                         // Old-fashioned raw SQL style, deprecated
 405                         $sql = $this->getSQL();
 406                         $sql .= ' ORDER BY ' . implode( ', ', $order );
 407                         $sql = $dbr->limitResult( $sql, $limit, $offset );
 408                         $res = $dbr->query( $sql, $fname );
 409                 }
 410
 411                 return $dbr->resultObject( $res );
 412         }
 413
 414         /**
 415          * Somewhat deprecated, you probably want to be using execute()
 416          * @param int|bool $offset
 417          * @param int|bool $limit
 418          * @return ResultWrapper
 419          */
 420         function doQuery( $offset = false, $limit = false ) {
 421                 if ( $this->isCached() && $this->isCacheable() ) {
 422                         return $this->fetchFromCache( $limit, $offset );
 423                 } else {
 424                         return $this->reallyDoQuery( $limit, $offset );
 425                 }
 426         }
 427
 428         /**
 429          * Fetch the query results from the query cache
 430          * @param int|bool $limit Numerical limit or false for no limit
 431          * @param int|bool $offset Numerical offset or false for no offset
 432          * @return ResultWrapper
 433          * @since 1.18
 434          */
 435         function fetchFromCache( $limit, $offset = false ) {
 436                 $dbr = wfGetDB( DB_SLAVE );
 437                 $options = array();
 438                 if ( $limit !== false ) {
 439                         $options['LIMIT'] = intval( $limit );
 440                 }
 441                 if ( $offset !== false ) {
 442                         $options['OFFSET'] = intval( $offset );
 443                 }
 444                 if ( $this->sortDescending() ) {
 445                         $options['ORDER BY'] = 'qc_value DESC';
 446                 } else {
 447                         $options['ORDER BY'] = 'qc_value ASC';
 448                 }
 449                 $res = $dbr->select( 'querycache', array( 'qc_type',
 450                                 'namespace' => 'qc_namespace',
 451                                 'title' => 'qc_title',
 452                                 'value' => 'qc_value' ),
 453                                 array( 'qc_type' => $this->getName() ),
 454                                 __METHOD__, $options
 455                 );
 456                 return $dbr->resultObject( $res );
 457         }
 458
 459         public function getCachedTimestamp() {
 460                 if ( is_null( $this->cachedTimestamp ) ) {
 461                         $dbr = wfGetDB( DB_SLAVE );
 462                         $fname = get_class( $this ) . '::getCachedTimestamp';
 463                         $this->cachedTimestamp = $dbr->selectField( 'querycache_info', 'qci_timestamp',
 464                                 array( 'qci_type' => $this->getName() ), $fname );
 465                 }
 466                 return $this->cachedTimestamp;
 467         }
 468
 469         /**
 470          * This is the actual workhorse. It does everything needed to make a
 471          * real, honest-to-gosh query page.
 472          * @param string $par
 473          * @return int
 474          */
 475         function execute( $par ) {
 476                 global $wgQueryCacheLimit, $wgDisableQueryPageUpdate;
 477
 478                 $user = $this->getUser();
 479                 if ( !$this->userCanExecute( $user ) ) {
 480                         $this->displayRestrictionError();
 481                         return;
 482                 }
 483
 484                 $this->setHeaders();
 485                 $this->outputHeader();
 486
 487                 $out = $this->getOutput();
 488
 489                 if ( $this->isCached() && !$this->isCacheable() ) {
 490                         $out->addWikiMsg( 'querypage-disabled' );
 491                         return 0;
 492                 }
 493
 494                 $out->setSyndicated( $this->isSyndicated() );
 495
 496                 if ( $this->limit == 0 && $this->offset == 0 ) {
 497                         list( $this->limit, $this->offset ) = $this->getRequest()->getLimitOffset();
 498                 }
 499
 500                 // @todo Use doQuery()
 501                 if ( !$this->isCached() ) {
 502                         # select one extra row for navigation
 503                         $res = $this->reallyDoQuery( $this->limit + 1, $this->offset );
 504                 } else {
 505                         # Get the cached result, select one extra row for navigation
 506                         $res = $this->fetchFromCache( $this->limit + 1, $this->offset );
 507                         if ( !$this->listoutput ) {
 508
 509                                 # Fetch the timestamp of this update
 510                                 $ts = $this->getCachedTimestamp();
 511                                 $lang = $this->getLanguage();
 512                                 $maxResults = $lang->formatNum( $wgQueryCacheLimit );
 513
 514                                 if ( $ts ) {
 515                                         $updated = $lang->userTimeAndDate( $ts, $user );
 516                                         $updateddate = $lang->userDate( $ts, $user );
 517                                         $updatedtime = $lang->userTime( $ts, $user );
 518                                         $out->addMeta( 'Data-Cache-Time', $ts );
 519                                         $out->addJsConfigVars( 'dataCacheTime', $ts );
 520                                         $out->addWikiMsg( 'perfcachedts', $updated, $updateddate, $updatedtime, $maxResults );
 521                                 } else {
 522                                         $out->addWikiMsg( 'perfcached', $maxResults );
 523                                 }
 524
 525                                 # If updates on this page have been disabled, let the user know
 526                                 # that the data set won't be refreshed for now
 527                                 if ( is_array( $wgDisableQueryPageUpdate )
 528                                         && in_array( $this->getName(), $wgDisableQueryPageUpdate )
 529                                 ) {
 530                                         $out->wrapWikiMsg(
 531                                                 "<div class=\"mw-querypage-no-updates\">\n$1\n</div>",
 532                                                 'querypage-no-updates'
 533                                         );
 534                                 }
 535                         }
 536                 }
 537
 538                 $this->numRows = $res->numRows();
 539
 540                 $dbr = wfGetDB( DB_SLAVE );
 541                 $this->preprocessResults( $dbr, $res );
 542
 543                 $out->addHTML( Xml::openElement( 'div', array( 'class' => 'mw-spcontent' ) ) );
 544
 545                 # Top header and navigation
 546                 if ( $this->shownavigation ) {
 547                         $out->addHTML( $this->getPageHeader() );
 548                         if ( $this->numRows > 0 ) {
 549                                 $out->addHTML( $this->msg( 'showingresultsinrange' )->numParams(
 550                                         min( $this->numRows, $this->limit ), # do not show the one extra row, if exist
 551                                         $this->offset + 1, ( min( $this->numRows, $this->limit ) + $this->offset ) )->parseAsBlock() );
 552                                 # Disable the "next" link when we reach the end
 553                                 $paging = $this->getLanguage()->viewPrevNext( $this->getPageTitle( $par ), $this->offset,
 554                                         $this->limit, $this->linkParameters(), ( $this->numRows <= $this->limit ) );
 555                                 $out->addHTML( '<p>' . $paging . '</p>' );
 556                         } else {
 557                                 # No results to show, so don't bother with "showing X of Y" etc.
 558                                 # -- just let the user know and give up now
 559                                 $out->addWikiMsg( 'specialpage-empty' );
 560                                 $out->addHTML( Xml::closeElement( 'div' ) );
 561                                 return;
 562                         }
 563                 }
 564
 565                 # The actual results; specialist subclasses will want to handle this
 566                 # with more than a straight list, so we hand them the info, plus
 567                 # an OutputPage, and let them get on with it
 568                 $this->outputResults( $out,
 569                         $this->getSkin(),
 570                         $dbr, # Should use a ResultWrapper for this
 571                         $res,
 572                         min( $this->numRows, $this->limit ), # do not format the one extra row, if exist
 573                         $this->offset );
 574
 575                 # Repeat the paging links at the bottom
 576                 if ( $this->shownavigation ) {
 577                         $out->addHTML( '<p>' . $paging . '</p>' );
 578                 }
 579
 580                 $out->addHTML( Xml::closeElement( 'div' ) );
 581
 582                 return min( $this->numRows, $this->limit ); # do not return the one extra row, if exist
 583         }
 584
 585         /**
 586          * Format and output report results using the given information plus
 587          * OutputPage
 588          *
 589          * @param OutputPage $out OutputPage to print to
 590          * @param Skin $skin User skin to use
 591          * @param DatabaseBase $dbr Database (read) connection to use
 592          * @param ResultWrapper $res Result pointer
 593          * @param int $num Number of available result rows
 594          * @param int $offset Paging offset
 595          */
 596         protected function outputResults( $out, $skin, $dbr, $res, $num, $offset ) {
 597                 global $wgContLang;
 598
 599                 if ( $num > 0 ) {
 600                         $html = array();
 601                         if ( !$this->listoutput ) {
 602                                 $html[] = $this->openList( $offset );
 603                         }
 604
 605                         # $res might contain the whole 1,000 rows, so we read up to
 606                         # $num [should update this to use a Pager]
 607                         // @codingStandardsIgnoreStart Generic.CodeAnalysis.ForLoopWithTestFunctionCall.NotAllowed
 608                         for ( $i = 0; $i < $num && $row = $res->fetchObject(); $i++ ) {
 609                                 // @codingStandardsIgnoreEnd
 610                                 $line = $this->formatResult( $skin, $row );
 611                                 if ( $line ) {
 612                                         $attr = ( isset( $row->usepatrol ) && $row->usepatrol && $row->patrolled == 0 )
 613                                                 ? ' class="not-patrolled"'
 614                                                 : '';
 615                                         $html[] = $this->listoutput
 616                                                 ? $line
 617                                                 : "<li{$attr}>{$line}</li>\n";
 618                                 }
 619                         }
 620
 621                         # Flush the final result
 622                         if ( $this->tryLastResult() ) {
 623                                 $row = null;
 624                                 $line = $this->formatResult( $skin, $row );
 625                                 if ( $line ) {
 626                                         $attr = ( isset( $row->usepatrol ) && $row->usepatrol && $row->patrolled == 0 )
 627                                                 ? ' class="not-patrolled"'
 628                                                 : '';
 629                                         $html[] = $this->listoutput
 630                                                 ? $line
 631                                                 : "<li{$attr}>{$line}</li>\n";
 632                                 }
 633                         }
 634
 635                         if ( !$this->listoutput ) {
 636                                 $html[] = $this->closeList();
 637                         }
 638
 639                         $html = $this->listoutput
 640                                 ? $wgContLang->listToText( $html )
 641                                 : implode( '', $html );
 642
 643                         $out->addHTML( $html );
 644                 }
 645         }
 646
 647         /**
 648          * @param int $offset
 649          * @return string
 650          */
 651         function openList( $offset ) {
 652                 return "\n<ol start='" . ( $offset + 1 ) . "' class='special'>\n";
 653         }
 654
 655         /**
 656          * @return string
 657          */
 658         function closeList() {
 659                 return "</ol>\n";
 660         }
 661
 662         /**
 663          * Do any necessary preprocessing of the result object.
 664          * @param DatabaseBase $db
 665          * @param ResultWrapper $res
 666          */
 667         function preprocessResults( $db, $res ) {
 668         }
 669
 670         /**
 671          * Similar to above, but packaging in a syndicated feed instead of a web page
 672          * @param string $class
 673          * @param int $limit
 674          * @return bool
 675          */
 676         function doFeed( $class = '', $limit = 50 ) {
 677                 global $wgFeed, $wgFeedClasses, $wgFeedLimit;
 678
 679                 if ( !$wgFeed ) {
 680                         $this->getOutput()->addWikiMsg( 'feed-unavailable' );
 681                         return false;
 682                 }
 683
 684                 $limit = min( $limit, $wgFeedLimit );
 685
 686                 if ( isset( $wgFeedClasses[$class] ) ) {
 687                         /** @var RSSFeed|AtomFeed $feed */
 688                         $feed = new $wgFeedClasses[$class](
 689                                 $this->feedTitle(),
 690                                 $this->feedDesc(),
 691                                 $this->feedUrl() );
 692                         $feed->outHeader();
 693
 694                         $res = $this->reallyDoQuery( $limit, 0 );
 695                         foreach ( $res as $obj ) {
 696                                 $item = $this->feedResult( $obj );
 697                                 if ( $item ) {
 698                                         $feed->outItem( $item );
 699                                 }
 700                         }
 701
 702                         $feed->outFooter();
 703                         return true;
 704                 } else {
 705                         return false;
 706                 }
 707         }
 708
 709         /**
 710          * Override for custom handling. If the titles/links are ok, just do
 711          * feedItemDesc()
 712          * @param object $row
 713          * @return FeedItem|null
 714          */
 715         function feedResult( $row ) {
 716                 if ( !isset( $row->title ) ) {
 717                         return null;
 718                 }
 719                 $title = Title::makeTitle( intval( $row->namespace ), $row->title );
 720                 if ( $title ) {
 721                         $date = isset( $row->timestamp ) ? $row->timestamp : '';
 722                         $comments = '';
 723                         if ( $title ) {
 724                                 $talkpage = $title->getTalkPage();
 725                                 $comments = $talkpage->getFullURL();
 726                         }
 727
 728                         return new FeedItem(
 729                                 $title->getPrefixedText(),
 730                                 $this->feedItemDesc( $row ),
 731                                 $title->getFullURL(),
 732                                 $date,
 733                                 $this->feedItemAuthor( $row ),
 734                                 $comments );
 735                 } else {
 736                         return null;
 737                 }
 738         }
 739
 740         function feedItemDesc( $row ) {
 741                 return isset( $row->comment ) ? htmlspecialchars( $row->comment ) : '';
 742         }
 743
 744         function feedItemAuthor( $row ) {
 745                 return isset( $row->user_text ) ? $row->user_text : '';
 746         }
 747
 748         function feedTitle() {
 749                 global $wgLanguageCode, $wgSitename;
 750                 $desc = $this->getDescription();
 751                 return "$wgSitename - $desc [$wgLanguageCode]";
 752         }
 753
 754         function feedDesc() {
 755                 return $this->msg( 'tagline' )->text();
 756         }
 757
 758         function feedUrl() {
 759                 return $this->getPageTitle()->getFullURL();
 760         }
 761 }
 762
 763 /**
 764  * Class definition for a wanted query page like
 765  * WantedPages, WantedTemplates, etc
 766  */
 767 abstract class WantedQueryPage extends QueryPage {
 768         function isExpensive() {
 769                 return true;
 770         }
 771
 772         function isSyndicated() {
 773                 return false;
 774         }
 775
 776         /**
 777          * Cache page existence for performance
 778          * @param DatabaseBase $db
 779          * @param ResultWrapper $res
 780          */
 781         function preprocessResults( $db, $res ) {
 782                 if ( !$res->numRows() ) {
 783                         return;
 784                 }
 785
 786                 $batch = new LinkBatch;
 787                 foreach ( $res as $row ) {
 788                         $batch->add( $row->namespace, $row->title );
 789                 }
 790                 $batch->execute();
 791
 792                 // Back to start for display
 793                 $res->seek( 0 );
 794         }
 795
 796         /**
 797          * Should formatResult() always check page existence, even if
 798          * the results are fresh?  This is a (hopefully temporary)
 799          * kluge for Special:WantedFiles, which may contain false
 800          * positives for files that exist e.g. in a shared repo (bug
 801          * 6220).
 802          * @return bool
 803          */
 804         function forceExistenceCheck() {
 805                 return false;
 806         }
 807
 808         /**
 809          * Format an individual result
 810          *
 811          * @param Skin $skin Skin to use for UI elements
 812          * @param object $result Result row
 813          * @return string
 814          */
 815         public function formatResult( $skin, $result ) {
 816                 $title = Title::makeTitleSafe( $result->namespace, $result->title );
 817                 if ( $title instanceof Title ) {
 818                         if ( $this->isCached() || $this->forceExistenceCheck() ) {
 819                                 $pageLink = $title->isKnown()
 820                                         ? '<del>' . Linker::link( $title ) . '</del>'
 821                                         : Linker::link(
 822                                                 $title,
 823                                                 null,
 824                                                 array(),
 825                                                 array(),
 826                                                 array( 'broken' )
 827                                         );
 828                         } else {
 829                                 $pageLink = Linker::link(
 830                                         $title,
 831                                         null,
 832                                         array(),
 833                                         array(),
 834                                         array( 'broken' )
 835                                 );
 836                         }
 837                         return $this->getLanguage()->specialList( $pageLink, $this->makeWlhLink( $title, $result ) );
 838                 } else {
 839                         return $this->msg( 'wantedpages-badtitle', $result->title )->escaped();
 840                 }
 841         }
 842
 843         /**
 844          * Make a "what links here" link for a given title
 845          *
 846          * @param Title $title Title to make the link for
 847          * @param object $result Result row
 848          * @return string
 849          */
 850         private function makeWlhLink( $title, $result ) {
 851                 $wlh = SpecialPage::getTitleFor( 'Whatlinkshere', $title->getPrefixedText() );
 852                 $label = $this->msg( 'nlinks' )->numParams( $result->value )->escaped();
 853                 return Linker::link( $wlh, $label );
 854         }
 855 }