includes/specials/SpecialWhatLinksHere.php

   1 <?php
   2 /**
   3  * Implements Special:Whatlinkshere
   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  * @todo Use some variant of Pager or something; the pagination here is lousy.
  22  */
  23
  24 use Wikimedia\Rdbms\IDatabase;
  25
  26 /**
  27  * Implements Special:Whatlinkshere
  28  *
  29  * @ingroup SpecialPage
  30  */
  31 class SpecialWhatLinksHere extends IncludableSpecialPage {
  32         /** @var FormOptions */
  33         protected $opts;
  34
  35         protected $selfTitle;
  36
  37         /** @var Title */
  38         protected $target;
  39
  40         protected $limits = [ 20, 50, 100, 250, 500 ];
  41
  42         public function __construct() {
  43                 parent::__construct( 'Whatlinkshere' );
  44         }
  45
  46         function execute( $par ) {
  47                 $out = $this->getOutput();
  48
  49                 $this->setHeaders();
  50                 $this->outputHeader();
  51                 $this->addHelpLink( 'Help:What links here' );
  52
  53                 $opts = new FormOptions();
  54
  55                 $opts->add( 'target', '' );
  56                 $opts->add( 'namespace', '', FormOptions::INTNULL );
  57                 $opts->add( 'limit', $this->getConfig()->get( 'QueryPageDefaultLimit' ) );
  58                 $opts->add( 'from', 0 );
  59                 $opts->add( 'back', 0 );
  60                 $opts->add( 'hideredirs', false );
  61                 $opts->add( 'hidetrans', false );
  62                 $opts->add( 'hidelinks', false );
  63                 $opts->add( 'hideimages', false );
  64                 $opts->add( 'invert', false );
  65
  66                 $opts->fetchValuesFromRequest( $this->getRequest() );
  67                 $opts->validateIntBounds( 'limit', 0, 5000 );
  68
  69                 // Give precedence to subpage syntax
  70                 if ( $par !== null ) {
  71                         $opts->setValue( 'target', $par );
  72                 }
  73
  74                 // Bind to member variable
  75                 $this->opts = $opts;
  76
  77                 $this->target = Title::newFromText( $opts->getValue( 'target' ) );
  78                 if ( !$this->target ) {
  79                         if ( !$this->including() ) {
  80                                 $out->addHTML( $this->whatlinkshereForm() );
  81                         }
  82
  83                         return;
  84                 }
  85
  86                 $this->getSkin()->setRelevantTitle( $this->target );
  87
  88                 $this->selfTitle = $this->getPageTitle( $this->target->getPrefixedDBkey() );
  89
  90                 $out->setPageTitle( $this->msg( 'whatlinkshere-title', $this->target->getPrefixedText() ) );
  91                 $out->addBacklinkSubtitle( $this->target );
  92                 $this->showIndirectLinks(
  93                         0,
  94                         $this->target,
  95                         $opts->getValue( 'limit' ),
  96                         $opts->getValue( 'from' ),
  97                         $opts->getValue( 'back' )
  98                 );
  99         }
 100
 101         /**
 102          * @param int $level Recursion level
 103          * @param Title $target Target title
 104          * @param int $limit Number of entries to display
 105          * @param int $from Display from this article ID (default: 0)
 106          * @param int $back Display from this article ID at backwards scrolling (default: 0)
 107          */
 108         function showIndirectLinks( $level, $target, $limit, $from = 0, $back = 0 ) {
 109                 $out = $this->getOutput();
 110                 $dbr = wfGetDB( DB_REPLICA );
 111
 112                 $hidelinks = $this->opts->getValue( 'hidelinks' );
 113                 $hideredirs = $this->opts->getValue( 'hideredirs' );
 114                 $hidetrans = $this->opts->getValue( 'hidetrans' );
 115                 $hideimages = $target->getNamespace() != NS_FILE || $this->opts->getValue( 'hideimages' );
 116
 117                 $fetchlinks = ( !$hidelinks || !$hideredirs );
 118
 119                 // Build query conds in concert for all three tables...
 120                 $conds = [];
 121                 $conds['pagelinks'] = [
 122                         'pl_namespace' => $target->getNamespace(),
 123                         'pl_title' => $target->getDBkey(),
 124                 ];
 125                 $conds['templatelinks'] = [
 126                         'tl_namespace' => $target->getNamespace(),
 127                         'tl_title' => $target->getDBkey(),
 128                 ];
 129                 $conds['imagelinks'] = [
 130                         'il_to' => $target->getDBkey(),
 131                 ];
 132
 133                 $namespace = $this->opts->getValue( 'namespace' );
 134                 $invert = $this->opts->getValue( 'invert' );
 135                 $nsComparison = ( $invert ? '!= ' : '= ' ) . $dbr->addQuotes( $namespace );
 136                 if ( is_int( $namespace ) ) {
 137                         $conds['pagelinks'][] = "pl_from_namespace $nsComparison";
 138                         $conds['templatelinks'][] = "tl_from_namespace $nsComparison";
 139                         $conds['imagelinks'][] = "il_from_namespace $nsComparison";
 140                 }
 141
 142                 if ( $from ) {
 143                         $conds['templatelinks'][] = "tl_from >= $from";
 144                         $conds['pagelinks'][] = "pl_from >= $from";
 145                         $conds['imagelinks'][] = "il_from >= $from";
 146                 }
 147
 148                 if ( $hideredirs ) {
 149                         $conds['pagelinks']['rd_from'] = null;
 150                 } elseif ( $hidelinks ) {
 151                         $conds['pagelinks'][] = 'rd_from is NOT NULL';
 152                 }
 153
 154                 $queryFunc = function ( IDatabase $dbr, $table, $fromCol ) use (
 155                         $conds, $target, $limit
 156                 ) {
 157                         // Read an extra row as an at-end check
 158                         $queryLimit = $limit + 1;
 159                         $on = [
 160                                 "rd_from = $fromCol",
 161                                 'rd_title' => $target->getDBkey(),
 162                                 'rd_interwiki = ' . $dbr->addQuotes( '' ) . ' OR rd_interwiki IS NULL'
 163                         ];
 164                         $on['rd_namespace'] = $target->getNamespace();
 165                         // Inner LIMIT is 2X in case of stale backlinks with wrong namespaces
 166                         $subQuery = $dbr->buildSelectSubquery(
 167                                 [ $table, 'redirect', 'page' ],
 168                                 [ $fromCol, 'rd_from' ],
 169                                 $conds[$table],
 170                                 __CLASS__ . '::showIndirectLinks',
 171                                 // Force JOIN order per T106682 to avoid large filesorts
 172                                 [ 'ORDER BY' => $fromCol, 'LIMIT' => 2 * $queryLimit, 'STRAIGHT_JOIN' ],
 173                                 [
 174                                         'page' => [ 'JOIN', "$fromCol = page_id" ],
 175                                         'redirect' => [ 'LEFT JOIN', $on ]
 176                                 ]
 177                         );
 178                         return $dbr->select(
 179                                 [ 'page', 'temp_backlink_range' => $subQuery ],
 180                                 [ 'page_id', 'page_namespace', 'page_title', 'rd_from', 'page_is_redirect' ],
 181                                 [],
 182                                 __CLASS__ . '::showIndirectLinks',
 183                                 [ 'ORDER BY' => 'page_id', 'LIMIT' => $queryLimit ],
 184                                 [ 'page' => [ 'JOIN', "$fromCol = page_id" ] ]
 185                         );
 186                 };
 187
 188                 if ( $fetchlinks ) {
 189                         $plRes = $queryFunc( $dbr, 'pagelinks', 'pl_from' );
 190                 }
 191
 192                 if ( !$hidetrans ) {
 193                         $tlRes = $queryFunc( $dbr, 'templatelinks', 'tl_from' );
 194                 }
 195
 196                 if ( !$hideimages ) {
 197                         $ilRes = $queryFunc( $dbr, 'imagelinks', 'il_from' );
 198                 }
 199
 200                 if ( ( !$fetchlinks || !$plRes->numRows() )
 201                         && ( $hidetrans || !$tlRes->numRows() )
 202                         && ( $hideimages || !$ilRes->numRows() )
 203                 ) {
 204                         if ( $level == 0 && !$this->including() ) {
 205                                 $out->addHTML( $this->whatlinkshereForm() );
 206
 207                                 // Show filters only if there are links
 208                                 if ( $hidelinks || $hidetrans || $hideredirs || $hideimages ) {
 209                                         $out->addHTML( $this->getFilterPanel() );
 210                                 }
 211                                 $msgKey = is_int( $namespace ) ? 'nolinkshere-ns' : 'nolinkshere';
 212                                 $link = $this->getLinkRenderer()->makeLink(
 213                                         $this->target,
 214                                         null,
 215                                         [],
 216                                         $this->target->isRedirect() ? [ 'redirect' => 'no' ] : []
 217                                 );
 218
 219                                 $errMsg = $this->msg( $msgKey )
 220                                         ->params( $this->target->getPrefixedText() )
 221                                         ->rawParams( $link )
 222                                         ->parseAsBlock();
 223                                 $out->addHTML( $errMsg );
 224                                 $out->setStatusCode( 404 );
 225                         }
 226
 227                         return;
 228                 }
 229
 230                 // Read the rows into an array and remove duplicates
 231                 // templatelinks comes second so that the templatelinks row overwrites the
 232                 // pagelinks row, so we get (inclusion) rather than nothing
 233                 $rows = [];
 234                 if ( $fetchlinks ) {
 235                         foreach ( $plRes as $row ) {
 236                                 $row->is_template = 0;
 237                                 $row->is_image = 0;
 238                                 $rows[$row->page_id] = $row;
 239                         }
 240                 }
 241                 if ( !$hidetrans ) {
 242                         foreach ( $tlRes as $row ) {
 243                                 $row->is_template = 1;
 244                                 $row->is_image = 0;
 245                                 $rows[$row->page_id] = $row;
 246                         }
 247                 }
 248                 if ( !$hideimages ) {
 249                         foreach ( $ilRes as $row ) {
 250                                 $row->is_template = 0;
 251                                 $row->is_image = 1;
 252                                 $rows[$row->page_id] = $row;
 253                         }
 254                 }
 255
 256                 // Sort by key and then change the keys to 0-based indices
 257                 ksort( $rows );
 258                 $rows = array_values( $rows );
 259
 260                 $numRows = count( $rows );
 261
 262                 // Work out the start and end IDs, for prev/next links
 263                 if ( $numRows > $limit ) {
 264                         // More rows available after these ones
 265                         // Get the ID from the last row in the result set
 266                         $nextId = $rows[$limit]->page_id;
 267                         // Remove undisplayed rows
 268                         $rows = array_slice( $rows, 0, $limit );
 269                 } else {
 270                         // No more rows after
 271                         $nextId = false;
 272                 }
 273                 $prevId = $from;
 274
 275                 // use LinkBatch to make sure, that all required data (associated with Titles)
 276                 // is loaded in one query
 277                 $lb = new LinkBatch();
 278                 foreach ( $rows as $row ) {
 279                         $lb->add( $row->page_namespace, $row->page_title );
 280                 }
 281                 $lb->execute();
 282
 283                 if ( $level == 0 && !$this->including() ) {
 284                         $out->addHTML( $this->whatlinkshereForm() );
 285                         $out->addHTML( $this->getFilterPanel() );
 286
 287                         $link = $this->getLinkRenderer()->makeLink(
 288                                 $this->target,
 289                                 null,
 290                                 [],
 291                                 $this->target->isRedirect() ? [ 'redirect' => 'no' ] : []
 292                         );
 293
 294                         $msg = $this->msg( 'linkshere' )
 295                                 ->params( $this->target->getPrefixedText() )
 296                                 ->rawParams( $link )
 297                                 ->parseAsBlock();
 298                         $out->addHTML( $msg );
 299
 300                         $prevnext = $this->getPrevNext( $prevId, $nextId );
 301                         $out->addHTML( $prevnext );
 302                 }
 303                 $out->addHTML( $this->listStart( $level ) );
 304                 foreach ( $rows as $row ) {
 305                         $nt = Title::makeTitle( $row->page_namespace, $row->page_title );
 306
 307                         if ( $row->rd_from && $level < 2 ) {
 308                                 $out->addHTML( $this->listItem( $row, $nt, $target, true ) );
 309                                 $this->showIndirectLinks(
 310                                         $level + 1,
 311                                         $nt,
 312                                         $this->getConfig()->get( 'MaxRedirectLinksRetrieved' )
 313                                 );
 314                                 $out->addHTML( Xml::closeElement( 'li' ) );
 315                         } else {
 316                                 $out->addHTML( $this->listItem( $row, $nt, $target ) );
 317                         }
 318                 }
 319
 320                 $out->addHTML( $this->listEnd() );
 321
 322                 if ( $level == 0 && !$this->including() ) {
 323                         $out->addHTML( $prevnext );
 324                 }
 325         }
 326
 327         protected function listStart( $level ) {
 328                 return Xml::openElement( 'ul', ( $level ? [] : [ 'id' => 'mw-whatlinkshere-list' ] ) );
 329         }
 330
 331         protected function listItem( $row, $nt, $target, $notClose = false ) {
 332                 $dirmark = $this->getLanguage()->getDirMark();
 333
 334                 # local message cache
 335                 static $msgcache = null;
 336                 if ( $msgcache === null ) {
 337                         static $msgs = [ 'isredirect', 'istemplate', 'semicolon-separator',
 338                                 'whatlinkshere-links', 'isimage', 'editlink' ];
 339                         $msgcache = [];
 340                         foreach ( $msgs as $msg ) {
 341                                 $msgcache[$msg] = $this->msg( $msg )->escaped();
 342                         }
 343                 }
 344
 345                 if ( $row->rd_from ) {
 346                         $query = [ 'redirect' => 'no' ];
 347                 } else {
 348                         $query = [];
 349                 }
 350
 351                 $link = $this->getLinkRenderer()->makeKnownLink(
 352                         $nt,
 353                         null,
 354                         $row->page_is_redirect ? [ 'class' => 'mw-redirect' ] : [],
 355                         $query
 356                 );
 357
 358                 // Display properties (redirect or template)
 359                 $propsText = '';
 360                 $props = [];
 361                 if ( $row->rd_from ) {
 362                         $props[] = $msgcache['isredirect'];
 363                 }
 364                 if ( $row->is_template ) {
 365                         $props[] = $msgcache['istemplate'];
 366                 }
 367                 if ( $row->is_image ) {
 368                         $props[] = $msgcache['isimage'];
 369                 }
 370
 371                 Hooks::run( 'WhatLinksHereProps', [ $row, $nt, $target, &$props ] );
 372
 373                 if ( count( $props ) ) {
 374                         $propsText = $this->msg( 'parentheses' )
 375                                 ->rawParams( implode( $msgcache['semicolon-separator'], $props ) )->escaped();
 376                 }
 377
 378                 # Space for utilities links, with a what-links-here link provided
 379                 $wlhLink = $this->wlhLink( $nt, $msgcache['whatlinkshere-links'], $msgcache['editlink'] );
 380                 $wlh = Xml::wrapClass(
 381                         $this->msg( 'parentheses' )->rawParams( $wlhLink )->escaped(),
 382                         'mw-whatlinkshere-tools'
 383                 );
 384
 385                 return $notClose ?
 386                         Xml::openElement( 'li' ) . "$link $propsText $dirmark $wlh\n" :
 387                         Xml::tags( 'li', null, "$link $propsText $dirmark $wlh" ) . "\n";
 388         }
 389
 390         protected function listEnd() {
 391                 return Xml::closeElement( 'ul' );
 392         }
 393
 394         protected function wlhLink( Title $target, $text, $editText ) {
 395                 static $title = null;
 396                 if ( $title === null ) {
 397                         $title = $this->getPageTitle();
 398                 }
 399
 400                 $linkRenderer = $this->getLinkRenderer();
 401
 402                 if ( $text !== null ) {
 403                         $text = new HtmlArmor( $text );
 404                 }
 405
 406                 // always show a "<- Links" link
 407                 $links = [
 408                         'links' => $linkRenderer->makeKnownLink(
 409                                 $title,
 410                                 $text,
 411                                 [],
 412                                 [ 'target' => $target->getPrefixedText() ]
 413                         ),
 414                 ];
 415
 416                 // if the page is editable, add an edit link
 417                 if (
 418                         // check user permissions
 419                         $this->getUser()->isAllowed( 'edit' ) &&
 420                         // check, if the content model is editable through action=edit
 421                         ContentHandler::getForTitle( $target )->supportsDirectEditing()
 422                 ) {
 423                         if ( $editText !== null ) {
 424                                 $editText = new HtmlArmor( $editText );
 425                         }
 426
 427                         $links['edit'] = $linkRenderer->makeKnownLink(
 428                                 $target,
 429                                 $editText,
 430                                 [],
 431                                 [ 'action' => 'edit' ]
 432                         );
 433                 }
 434
 435                 // build the links html
 436                 return $this->getLanguage()->pipeList( $links );
 437         }
 438
 439         function makeSelfLink( $text, $query ) {
 440                 if ( $text !== null ) {
 441                         $text = new HtmlArmor( $text );
 442                 }
 443
 444                 return $this->getLinkRenderer()->makeKnownLink(
 445                         $this->selfTitle,
 446                         $text,
 447                         [],
 448                         $query
 449                 );
 450         }
 451
 452         function getPrevNext( $prevId, $nextId ) {
 453                 $currentLimit = $this->opts->getValue( 'limit' );
 454                 $prev = $this->msg( 'whatlinkshere-prev' )->numParams( $currentLimit )->escaped();
 455                 $next = $this->msg( 'whatlinkshere-next' )->numParams( $currentLimit )->escaped();
 456
 457                 $changed = $this->opts->getChangedValues();
 458                 unset( $changed['target'] ); // Already in the request title
 459
 460                 if ( $prevId != 0 ) {
 461                         $overrides = [ 'from' => $this->opts->getValue( 'back' ) ];
 462                         $prev = $this->makeSelfLink( $prev, array_merge( $changed, $overrides ) );
 463                 }
 464                 if ( $nextId != 0 ) {
 465                         $overrides = [ 'from' => $nextId, 'back' => $prevId ];
 466                         $next = $this->makeSelfLink( $next, array_merge( $changed, $overrides ) );
 467                 }
 468
 469                 $limitLinks = [];
 470                 $lang = $this->getLanguage();
 471                 foreach ( $this->limits as $limit ) {
 472                         $prettyLimit = htmlspecialchars( $lang->formatNum( $limit ) );
 473                         $overrides = [ 'limit' => $limit ];
 474                         $limitLinks[] = $this->makeSelfLink( $prettyLimit, array_merge( $changed, $overrides ) );
 475                 }
 476
 477                 $nums = $lang->pipeList( $limitLinks );
 478
 479                 return $this->msg( 'viewprevnext' )->rawParams( $prev, $next, $nums )->escaped();
 480         }
 481
 482         function whatlinkshereForm() {
 483                 // We get nicer value from the title object
 484                 $this->opts->consumeValue( 'target' );
 485                 // Reset these for new requests
 486                 $this->opts->consumeValues( [ 'back', 'from' ] );
 487
 488                 $target = $this->target ? $this->target->getPrefixedText() : '';
 489                 $namespace = $this->opts->consumeValue( 'namespace' );
 490                 $nsinvert = $this->opts->consumeValue( 'invert' );
 491
 492                 # Build up the form
 493                 $f = Xml::openElement( 'form', [ 'action' => wfScript() ] );
 494
 495                 # Values that should not be forgotten
 496                 $f .= Html::hidden( 'title', $this->getPageTitle()->getPrefixedText() );
 497                 foreach ( $this->opts->getUnconsumedValues() as $name => $value ) {
 498                         $f .= Html::hidden( $name, $value );
 499                 }
 500
 501                 $f .= Xml::fieldset( $this->msg( 'whatlinkshere' )->text() );
 502
 503                 # Target input (.mw-searchInput enables suggestions)
 504                 $f .= Xml::inputLabel( $this->msg( 'whatlinkshere-page' )->text(), 'target',
 505                         'mw-whatlinkshere-target', 40, $target, [ 'class' => 'mw-searchInput' ] );
 506
 507                 $f .= ' ';
 508
 509                 # Namespace selector
 510                 $f .= Html::namespaceSelector(
 511                         [
 512                                 'selected' => $namespace,
 513                                 'all' => '',
 514                                 'label' => $this->msg( 'namespace' )->text(),
 515                                 'in-user-lang' => true,
 516                         ], [
 517                                 'name' => 'namespace',
 518                                 'id' => 'namespace',
 519                                 'class' => 'namespaceselector',
 520                         ]
 521                 );
 522
 523                 $f .= "\u{00A0}" .
 524                         Xml::checkLabel(
 525                                 $this->msg( 'invert' )->text(),
 526                                 'invert',
 527                                 'nsinvert',
 528                                 $nsinvert,
 529                                 [ 'title' => $this->msg( 'tooltip-whatlinkshere-invert' )->text() ]
 530                         );
 531
 532                 $f .= ' ';
 533
 534                 # Submit
 535                 $f .= Xml::submitButton( $this->msg( 'whatlinkshere-submit' )->text() );
 536
 537                 # Close
 538                 $f .= Xml::closeElement( 'fieldset' ) . Xml::closeElement( 'form' ) . "\n";
 539
 540                 return $f;
 541         }
 542
 543         /**
 544          * Create filter panel
 545          *
 546          * @return string HTML fieldset and filter panel with the show/hide links
 547          */
 548         function getFilterPanel() {
 549                 $show = $this->msg( 'show' )->escaped();
 550                 $hide = $this->msg( 'hide' )->escaped();
 551
 552                 $changed = $this->opts->getChangedValues();
 553                 unset( $changed['target'] ); // Already in the request title
 554
 555                 $links = [];
 556                 $types = [ 'hidetrans', 'hidelinks', 'hideredirs' ];
 557                 if ( $this->target->getNamespace() == NS_FILE ) {
 558                         $types[] = 'hideimages';
 559                 }
 560
 561                 // Combined message keys: 'whatlinkshere-hideredirs', 'whatlinkshere-hidetrans',
 562                 // 'whatlinkshere-hidelinks', 'whatlinkshere-hideimages'
 563                 // To be sure they will be found by grep
 564                 foreach ( $types as $type ) {
 565                         $chosen = $this->opts->getValue( $type );
 566                         $msg = $chosen ? $show : $hide;
 567                         $overrides = [ $type => !$chosen ];
 568                         $links[] = $this->msg( "whatlinkshere-{$type}" )->rawParams(
 569                                 $this->makeSelfLink( $msg, array_merge( $changed, $overrides ) ) )->escaped();
 570                 }
 571
 572                 return Xml::fieldset(
 573                         $this->msg( 'whatlinkshere-filters' )->text(),
 574                         $this->getLanguage()->pipeList( $links )
 575                 );
 576         }
 577
 578         /**
 579          * Return an array of subpages beginning with $search that this special page will accept.
 580          *
 581          * @param string $search Prefix to search for
 582          * @param int $limit Maximum number of results to return (usually 10)
 583          * @param int $offset Number of results to skip (usually 0)
 584          * @return string[] Matching subpages
 585          */
 586         public function prefixSearchSubpages( $search, $limit, $offset ) {
 587                 return $this->prefixSearchString( $search, $limit, $offset );
 588         }
 589
 590         protected function getGroupName() {
 591                 return 'pagetools';
 592         }
 593 }