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