includes/specialpage/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                 return $this->getConfig()->get( 'DisableQueryPages' );
 207         }
 208
 209         /**
 210          * Is the output of this query cacheable? Non-cacheable expensive pages
 211          * will be disabled in miser mode and will not have their results written
 212          * to the querycache table.
 213          * @return bool
 214          * @since 1.18
 215          */
 216         public function isCacheable() {
 217                 return true;
 218         }
 219
 220         /**
 221          * Whether or not the output of the page in question is retrieved from
 222          * the database cache.
 223          *
 224          * @return bool
 225          */
 226         function isCached() {
 227                 return $this->isExpensive() && $this->getConfig()->get( 'MiserMode' );
 228         }
 229
 230         /**
 231          * Sometime we don't want to build rss / atom feeds.
 232          *
 233          * @return bool
 234          */
 235         function isSyndicated() {
 236                 return true;
 237         }
 238
 239         /**
 240          * Formats the results of the query for display. The skin is the current
 241          * skin; you can use it for making links. The result is a single row of
 242          * result data. You should be able to grab SQL results off of it.
 243          * If the function returns false, the line output will be skipped.
 244          * @param Skin $skin
 245          * @param object $result Result row
 246          * @return string|bool String or false to skip
 247          */
 248         abstract function formatResult( $skin, $result );
 249
 250         /**
 251          * The content returned by this function will be output before any result
 252          *
 253          * @return string
 254          */
 255         function getPageHeader() {
 256                 return '';
 257         }
 258
 259         /**
 260          * If using extra form wheely-dealies, return a set of parameters here
 261          * as an associative array. They will be encoded and added to the paging
 262          * links (prev/next/lengths).
 263          *
 264          * @return array
 265          */
 266         function linkParameters() {
 267                 return array();
 268         }
 269
 270         /**
 271          * Some special pages (for example SpecialListusers) might not return the
 272          * current object formatted, but return the previous one instead.
 273          * Setting this to return true will ensure formatResult() is called
 274          * one more time to make sure that the very last result is formatted
 275          * as well.
 276          * @return bool
 277          */
 278         function tryLastResult() {
 279                 return false;
 280         }
 281
 282         /**
 283          * Clear the cache and save new results
 284          *
 285          * @param int|bool $limit Limit for SQL statement
 286          * @param bool $ignoreErrors Whether to ignore database errors
 287          * @throws DBError|Exception
 288          * @return bool|int
 289          */
 290         function recache( $limit, $ignoreErrors = true ) {
 291                 if ( !$this->isCacheable() ) {
 292                         return 0;
 293                 }
 294
 295                 $fname = get_class( $this ) . '::recache';
 296                 $dbw = wfGetDB( DB_MASTER );
 297                 if ( !$dbw ) {
 298                         return false;
 299                 }
 300
 301                 try {
 302                         # Do query
 303                         $res = $this->reallyDoQuery( $limit, false );
 304                         $num = false;
 305                         if ( $res ) {
 306                                 $num = $res->numRows();
 307                                 # Fetch results
 308                                 $vals = array();
 309                                 foreach ( $res as $row ) {
 310                                         if ( isset( $row->value ) ) {
 311                                                 if ( $this->usesTimestamps() ) {
 312                                                         $value = wfTimestamp( TS_UNIX,
 313                                                                 $row->value );
 314                                                 } else {
 315                                                         $value = intval( $row->value ); // @bug 14414
 316                                                 }
 317                                         } else {
 318                                                 $value = 0;
 319                                         }
 320
 321                                         $vals[] = array( 'qc_type' => $this->getName(),
 322                                                         'qc_namespace' => $row->namespace,
 323                                                         'qc_title' => $row->title,
 324                                                         'qc_value' => $value );
 325                                 }
 326
 327                                 $dbw->begin( __METHOD__ );
 328                                 # Clear out any old cached data
 329                                 $dbw->delete( 'querycache', array( 'qc_type' => $this->getName() ), $fname );
 330                                 # Save results into the querycache table on the master
 331                                 if ( count( $vals ) ) {
 332                                         $dbw->insert( 'querycache', $vals, __METHOD__ );
 333                                 }
 334                                 # Update the querycache_info record for the page
 335                                 $dbw->delete( 'querycache_info', array( 'qci_type' => $this->getName() ), $fname );
 336                                 $dbw->insert( 'querycache_info',
 337                                         array( 'qci_type' => $this->getName(), 'qci_timestamp' => $dbw->timestamp() ),
 338                                         $fname );
 339                                 $dbw->commit( __METHOD__ );
 340                         }
 341                 } catch ( DBError $e ) {
 342                         if ( !$ignoreErrors ) {
 343                                 throw $e; // report query error
 344                         }
 345                         $num = false; // set result to false to indicate error
 346                 }
 347
 348                 return $num;
 349         }
 350
 351         /**
 352          * Get a DB connection to be used for slow recache queries
 353          * @return DatabaseBase
 354          */
 355         function getRecacheDB() {
 356                 return wfGetDB( DB_SLAVE, array( $this->getName(), 'QueryPage::recache', 'vslow' ) );
 357         }
 358
 359         /**
 360          * Run the query and return the result
 361          * @param int|bool $limit Numerical limit or false for no limit
 362          * @param int|bool $offset Numerical offset or false for no offset
 363          * @return ResultWrapper
 364          * @since 1.18
 365          */
 366         function reallyDoQuery( $limit, $offset = false ) {
 367                 $fname = get_class( $this ) . "::reallyDoQuery";
 368                 $dbr = $this->getRecacheDB();
 369                 $query = $this->getQueryInfo();
 370                 $order = $this->getOrderFields();
 371
 372                 if ( $this->sortDescending() ) {
 373                         foreach ( $order as &$field ) {
 374                                 $field .= ' DESC';
 375                         }
 376                 }
 377
 378                 if ( is_array( $query ) ) {
 379                         $tables = isset( $query['tables'] ) ? (array)$query['tables'] : array();
 380                         $fields = isset( $query['fields'] ) ? (array)$query['fields'] : array();
 381                         $conds = isset( $query['conds'] ) ? (array)$query['conds'] : array();
 382                         $options = isset( $query['options'] ) ? (array)$query['options'] : array();
 383                         $join_conds = isset( $query['join_conds'] ) ? (array)$query['join_conds'] : array();
 384
 385                         if ( count( $order ) ) {
 386                                 $options['ORDER BY'] = $order;
 387                         }
 388
 389                         if ( $limit !== false ) {
 390                                 $options['LIMIT'] = intval( $limit );
 391                         }
 392
 393                         if ( $offset !== false ) {
 394                                 $options['OFFSET'] = intval( $offset );
 395                         }
 396
 397                         $res = $dbr->select( $tables, $fields, $conds, $fname,
 398                                         $options, $join_conds
 399                         );
 400                 } else {
 401                         // Old-fashioned raw SQL style, deprecated
 402                         $sql = $this->getSQL();
 403                         $sql .= ' ORDER BY ' . implode( ', ', $order );
 404                         $sql = $dbr->limitResult( $sql, $limit, $offset );
 405                         $res = $dbr->query( $sql, $fname );
 406                 }
 407
 408                 return $dbr->resultObject( $res );
 409         }
 410
 411         /**
 412          * Somewhat deprecated, you probably want to be using execute()
 413          * @param int|bool $offset
 414          * @param int|bool $limit
 415          * @return ResultWrapper
 416          */
 417         function doQuery( $offset = false, $limit = false ) {
 418                 if ( $this->isCached() && $this->isCacheable() ) {
 419                         return $this->fetchFromCache( $limit, $offset );
 420                 } else {
 421                         return $this->reallyDoQuery( $limit, $offset );
 422                 }
 423         }
 424
 425         /**
 426          * Fetch the query results from the query cache
 427          * @param int|bool $limit Numerical limit or false for no limit
 428          * @param int|bool $offset Numerical offset or false for no offset
 429          * @return ResultWrapper
 430          * @since 1.18
 431          */
 432         function fetchFromCache( $limit, $offset = false ) {
 433                 $dbr = wfGetDB( DB_SLAVE );
 434                 $options = array();
 435                 if ( $limit !== false ) {
 436                         $options['LIMIT'] = intval( $limit );
 437                 }
 438                 if ( $offset !== false ) {
 439                         $options['OFFSET'] = intval( $offset );
 440                 }
 441                 if ( $this->sortDescending() ) {
 442                         $options['ORDER BY'] = 'qc_value DESC';
 443                 } else {
 444                         $options['ORDER BY'] = 'qc_value ASC';
 445                 }
 446                 $res = $dbr->select( 'querycache', array( 'qc_type',
 447                                 'namespace' => 'qc_namespace',
 448                                 'title' => 'qc_title',
 449                                 'value' => 'qc_value' ),
 450                                 array( 'qc_type' => $this->getName() ),
 451                                 __METHOD__, $options
 452                 );
 453                 return $dbr->resultObject( $res );
 454         }
 455
 456         public function getCachedTimestamp() {
 457                 if ( is_null( $this->cachedTimestamp ) ) {
 458                         $dbr = wfGetDB( DB_SLAVE );
 459                         $fname = get_class( $this ) . '::getCachedTimestamp';
 460                         $this->cachedTimestamp = $dbr->selectField( 'querycache_info', 'qci_timestamp',
 461                                 array( 'qci_type' => $this->getName() ), $fname );
 462                 }
 463                 return $this->cachedTimestamp;
 464         }
 465
 466         /**
 467          * This is the actual workhorse. It does everything needed to make a
 468          * real, honest-to-gosh query page.
 469          * @param string $par
 470          */
 471         function execute( $par ) {
 472                 $user = $this->getUser();
 473                 if ( !$this->userCanExecute( $user ) ) {
 474                         $this->displayRestrictionError();
 475                         return;
 476                 }
 477
 478                 $this->setHeaders();
 479                 $this->outputHeader();
 480
 481                 $out = $this->getOutput();
 482
 483                 if ( $this->isCached() && !$this->isCacheable() ) {
 484                         $out->addWikiMsg( 'querypage-disabled' );
 485                         return;
 486                 }
 487
 488                 $out->setSyndicated( $this->isSyndicated() );
 489
 490                 if ( $this->limit == 0 && $this->offset == 0 ) {
 491                         list( $this->limit, $this->offset ) = $this->getRequest()->getLimitOffset();
 492                 }
 493
 494                 // @todo Use doQuery()
 495                 if ( !$this->isCached() ) {
 496                         # select one extra row for navigation
 497                         $res = $this->reallyDoQuery( $this->limit + 1, $this->offset );
 498                 } else {
 499                         # Get the cached result, select one extra row for navigation
 500                         $res = $this->fetchFromCache( $this->limit + 1, $this->offset );
 501                         if ( !$this->listoutput ) {
 502
 503                                 # Fetch the timestamp of this update
 504                                 $ts = $this->getCachedTimestamp();
 505                                 $lang = $this->getLanguage();
 506                                 $maxResults = $lang->formatNum( $this->getConfig()->get( 'QueryCacheLimit' ) );
 507
 508                                 if ( $ts ) {
 509                                         $updated = $lang->userTimeAndDate( $ts, $user );
 510                                         $updateddate = $lang->userDate( $ts, $user );
 511                                         $updatedtime = $lang->userTime( $ts, $user );
 512                                         $out->addMeta( 'Data-Cache-Time', $ts );
 513                                         $out->addJsConfigVars( 'dataCacheTime', $ts );
 514                                         $out->addWikiMsg( 'perfcachedts', $updated, $updateddate, $updatedtime, $maxResults );
 515                                 } else {
 516                                         $out->addWikiMsg( 'perfcached', $maxResults );
 517                                 }
 518
 519                                 # If updates on this page have been disabled, let the user know
 520                                 # that the data set won't be refreshed for now
 521                                 if ( is_array( $this->getConfig()->get( 'DisableQueryPageUpdate' ) )
 522                                         && in_array( $this->getName(), $this->getConfig()->get( 'DisableQueryPageUpdate' ) )
 523                                 ) {
 524                                         $out->wrapWikiMsg(
 525                                                 "<div class=\"mw-querypage-no-updates\">\n$1\n</div>",
 526                                                 'querypage-no-updates'
 527                                         );
 528                                 }
 529                         }
 530                 }
 531
 532                 $this->numRows = $res->numRows();
 533
 534                 $dbr = wfGetDB( DB_SLAVE );
 535                 $this->preprocessResults( $dbr, $res );
 536
 537                 $out->addHTML( Xml::openElement( 'div', array( 'class' => 'mw-spcontent' ) ) );
 538
 539                 # Top header and navigation
 540                 if ( $this->shownavigation ) {
 541                         $out->addHTML( $this->getPageHeader() );
 542                         if ( $this->numRows > 0 ) {
 543                                 $out->addHTML( $this->msg( 'showingresultsinrange' )->numParams(
 544                                         min( $this->numRows, $this->limit ), # do not show the one extra row, if exist
 545                                         $this->offset + 1, ( min( $this->numRows, $this->limit ) + $this->offset ) )->parseAsBlock() );
 546                                 # Disable the "next" link when we reach the end
 547                                 $paging = $this->getLanguage()->viewPrevNext( $this->getPageTitle( $par ), $this->offset,
 548                                         $this->limit, $this->linkParameters(), ( $this->numRows <= $this->limit ) );
 549                                 $out->addHTML( '<p>' . $paging . '</p>' );
 550                         } else {
 551                                 # No results to show, so don't bother with "showing X of Y" etc.
 552                                 # -- just let the user know and give up now
 553                                 $out->addWikiMsg( 'specialpage-empty' );
 554                                 $out->addHTML( Xml::closeElement( 'div' ) );
 555                                 return;
 556                         }
 557                 }
 558
 559                 # The actual results; specialist subclasses will want to handle this
 560                 # with more than a straight list, so we hand them the info, plus
 561                 # an OutputPage, and let them get on with it
 562                 $this->outputResults( $out,
 563                         $this->getSkin(),
 564                         $dbr, # Should use a ResultWrapper for this
 565                         $res,
 566                         min( $this->numRows, $this->limit ), # do not format the one extra row, if exist
 567                         $this->offset );
 568
 569                 # Repeat the paging links at the bottom
 570                 if ( $this->shownavigation ) {
 571                         $out->addHTML( '<p>' . $paging . '</p>' );
 572                 }
 573
 574                 $out->addHTML( Xml::closeElement( 'div' ) );
 575         }
 576
 577         /**
 578          * Format and output report results using the given information plus
 579          * OutputPage
 580          *
 581          * @param OutputPage $out OutputPage to print to
 582          * @param Skin $skin User skin to use
 583          * @param DatabaseBase $dbr Database (read) connection to use
 584          * @param ResultWrapper $res Result pointer
 585          * @param int $num Number of available result rows
 586          * @param int $offset Paging offset
 587          */
 588         protected function outputResults( $out, $skin, $dbr, $res, $num, $offset ) {
 589                 global $wgContLang;
 590
 591                 if ( $num > 0 ) {
 592                         $html = array();
 593                         if ( !$this->listoutput ) {
 594                                 $html[] = $this->openList( $offset );
 595                         }
 596
 597                         # $res might contain the whole 1,000 rows, so we read up to
 598                         # $num [should update this to use a Pager]
 599                         // @codingStandardsIgnoreStart Generic.CodeAnalysis.ForLoopWithTestFunctionCall.NotAllowed
 600                         for ( $i = 0; $i < $num && $row = $res->fetchObject(); $i++ ) {
 601                                 // @codingStandardsIgnoreEnd
 602                                 $line = $this->formatResult( $skin, $row );
 603                                 if ( $line ) {
 604                                         $attr = ( isset( $row->usepatrol ) && $row->usepatrol && $row->patrolled == 0 )
 605                                                 ? ' class="not-patrolled"'
 606                                                 : '';
 607                                         $html[] = $this->listoutput
 608                                                 ? $line
 609                                                 : "<li{$attr}>{$line}</li>\n";
 610                                 }
 611                         }
 612
 613                         # Flush the final result
 614                         if ( $this->tryLastResult() ) {
 615                                 $row = null;
 616                                 $line = $this->formatResult( $skin, $row );
 617                                 if ( $line ) {
 618                                         $attr = ( isset( $row->usepatrol ) && $row->usepatrol && $row->patrolled == 0 )
 619                                                 ? ' class="not-patrolled"'
 620                                                 : '';
 621                                         $html[] = $this->listoutput
 622                                                 ? $line
 623                                                 : "<li{$attr}>{$line}</li>\n";
 624                                 }
 625                         }
 626
 627                         if ( !$this->listoutput ) {
 628                                 $html[] = $this->closeList();
 629                         }
 630
 631                         $html = $this->listoutput
 632                                 ? $wgContLang->listToText( $html )
 633                                 : implode( '', $html );
 634
 635                         $out->addHTML( $html );
 636                 }
 637         }
 638
 639         /**
 640          * @param int $offset
 641          * @return string
 642          */
 643         function openList( $offset ) {
 644                 return "\n<ol start='" . ( $offset + 1 ) . "' class='special'>\n";
 645         }
 646
 647         /**
 648          * @return string
 649          */
 650         function closeList() {
 651                 return "</ol>\n";
 652         }
 653
 654         /**
 655          * Do any necessary preprocessing of the result object.
 656          * @param DatabaseBase $db
 657          * @param ResultWrapper $res
 658          */
 659         function preprocessResults( $db, $res ) {
 660         }
 661
 662         /**
 663          * Similar to above, but packaging in a syndicated feed instead of a web page
 664          * @param string $class
 665          * @param int $limit
 666          * @return bool
 667          */
 668         function doFeed( $class = '', $limit = 50 ) {
 669                 if ( !$this->getConfig()->get( 'Feed' ) ) {
 670                         $this->getOutput()->addWikiMsg( 'feed-unavailable' );
 671                         return false;
 672                 }
 673
 674                 $limit = min( $limit, $this->getConfig()->get( 'FeedLimit' ) );
 675
 676                 $feedClasses = $this->getConfig()->get( 'FeedClasses' );
 677                 if ( isset( $feedClasses[$class] ) ) {
 678                         /** @var RSSFeed|AtomFeed $feed */
 679                         $feed = new $feedClasses[$class](
 680                                 $this->feedTitle(),
 681                                 $this->feedDesc(),
 682                                 $this->feedUrl() );
 683                         $feed->outHeader();
 684
 685                         $res = $this->reallyDoQuery( $limit, 0 );
 686                         foreach ( $res as $obj ) {
 687                                 $item = $this->feedResult( $obj );
 688                                 if ( $item ) {
 689                                         $feed->outItem( $item );
 690                                 }
 691                         }
 692
 693                         $feed->outFooter();
 694                         return true;
 695                 } else {
 696                         return false;
 697                 }
 698         }
 699
 700         /**
 701          * Override for custom handling. If the titles/links are ok, just do
 702          * feedItemDesc()
 703          * @param object $row
 704          * @return FeedItem|null
 705          */
 706         function feedResult( $row ) {
 707                 if ( !isset( $row->title ) ) {
 708                         return null;
 709                 }
 710                 $title = Title::makeTitle( intval( $row->namespace ), $row->title );
 711                 if ( $title ) {
 712                         $date = isset( $row->timestamp ) ? $row->timestamp : '';
 713                         $comments = '';
 714                         if ( $title ) {
 715                                 $talkpage = $title->getTalkPage();
 716                                 $comments = $talkpage->getFullURL();
 717                         }
 718
 719                         return new FeedItem(
 720                                 $title->getPrefixedText(),
 721                                 $this->feedItemDesc( $row ),
 722                                 $title->getFullURL(),
 723                                 $date,
 724                                 $this->feedItemAuthor( $row ),
 725                                 $comments );
 726                 } else {
 727                         return null;
 728                 }
 729         }
 730
 731         function feedItemDesc( $row ) {
 732                 return isset( $row->comment ) ? htmlspecialchars( $row->comment ) : '';
 733         }
 734
 735         function feedItemAuthor( $row ) {
 736                 return isset( $row->user_text ) ? $row->user_text : '';
 737         }
 738
 739         function feedTitle() {
 740                 $desc = $this->getDescription();
 741                 $code = $this->getConfig()->get( 'LanguageCode' );
 742                 $sitename = $this->getConfig()->get( 'Sitename' );
 743                 return "$sitename - $desc [$code]";
 744         }
 745
 746         function feedDesc() {
 747                 return $this->msg( 'tagline' )->text();
 748         }
 749
 750         function feedUrl() {
 751                 return $this->getPageTitle()->getFullURL();
 752         }
 753 }