includes/specials/SpecialRecentChangesLinked.php

   1 <?php
   2 /**
   3  * Implements Special:Recentchangeslinked
   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 use MediaWiki\MediaWikiServices;
  25
  26 /**
  27  * This is to display changes made to all articles linked in an article.
  28  *
  29  * @ingroup SpecialPage
  30  */
  31 class SpecialRecentChangesLinked extends SpecialRecentChanges {
  32         /** @var bool|Title */
  33         protected $rclTargetTitle;
  34
  35         function __construct() {
  36                 parent::__construct( 'Recentchangeslinked' );
  37         }
  38
  39         public function getDefaultOptions() {
  40                 $opts = parent::getDefaultOptions();
  41                 $opts->add( 'target', '' );
  42                 $opts->add( 'showlinkedto', false );
  43
  44                 return $opts;
  45         }
  46
  47         public function parseParameters( $par, FormOptions $opts ) {
  48                 $opts['target'] = $par;
  49         }
  50
  51         /**
  52          * @inheritDoc
  53          */
  54         protected function doMainQuery( $tables, $select, $conds, $query_options,
  55                 $join_conds, FormOptions $opts
  56         ) {
  57                 $target = $opts['target'];
  58                 $showlinkedto = $opts['showlinkedto'];
  59                 $limit = $opts['limit'];
  60
  61                 if ( $target === '' ) {
  62                         return false;
  63                 }
  64                 $outputPage = $this->getOutput();
  65                 $title = Title::newFromText( $target );
  66                 if ( !$title || $title->isExternal() ) {
  67                         $outputPage->addHTML(
  68                                 Html::errorBox( $this->msg( 'allpagesbadtitle' )->parse() )
  69                         );
  70                         return false;
  71                 }
  72
  73                 $outputPage->setPageTitle( $this->msg( 'recentchangeslinked-title', $title->getPrefixedText() ) );
  74
  75                 /*
  76                  * Ordinary links are in the pagelinks table, while transclusions are
  77                  * in the templatelinks table, categorizations in categorylinks and
  78                  * image use in imagelinks.  We need to somehow combine all these.
  79                  * Special:Whatlinkshere does this by firing multiple queries and
  80                  * merging the results, but the code we inherit from our parent class
  81                  * expects only one result set so we use UNION instead.
  82                  */
  83
  84                 $dbr = wfGetDB( DB_REPLICA, 'recentchangeslinked' );
  85                 $id = $title->getArticleID();
  86                 $ns = $title->getNamespace();
  87                 $dbkey = $title->getDBkey();
  88
  89                 $rcQuery = RecentChange::getQueryInfo();
  90                 $tables = array_merge( $tables, $rcQuery['tables'] );
  91                 $select = array_merge( $rcQuery['fields'], $select );
  92                 $join_conds = array_merge( $join_conds, $rcQuery['joins'] );
  93
  94                 // left join with watchlist table to highlight watched rows
  95                 $uid = $this->getUser()->getId();
  96                 if ( $uid && MediaWikiServices::getInstance()
  97                                 ->getPermissionManager()
  98                                 ->userHasRight( $this->getUser(), 'viewmywatchlist' )
  99                 ) {
 100                         $tables[] = 'watchlist';
 101                         $select[] = 'wl_user';
 102                         $join_conds['watchlist'] = [ 'LEFT JOIN', [
 103                                 'wl_user' => $uid,
 104                                 'wl_title=rc_title',
 105                                 'wl_namespace=rc_namespace'
 106                         ] ];
 107                 }
 108
 109                 // JOIN on page, used for 'last revision' filter highlight
 110                 $tables[] = 'page';
 111                 $join_conds['page'] = [ 'LEFT JOIN', 'rc_cur_id=page_id' ];
 112                 $select[] = 'page_latest';
 113
 114                 $tagFilter = $opts['tagfilter'] ? explode( '|', $opts['tagfilter'] ) : [];
 115                 ChangeTags::modifyDisplayQuery(
 116                         $tables,
 117                         $select,
 118                         $conds,
 119                         $join_conds,
 120                         $query_options,
 121                         $tagFilter
 122                 );
 123
 124                 if ( $dbr->unionSupportsOrderAndLimit() ) {
 125                         if ( count( $tagFilter ) > 1 ) {
 126                                 // ChangeTags::modifyDisplayQuery() will have added DISTINCT.
 127                                 // To prevent this from causing query performance problems, we need to add
 128                                 // a GROUP BY, and add rc_id to the ORDER BY.
 129                                 $order = [
 130                                         'GROUP BY' => 'rc_timestamp, rc_id',
 131                                         'ORDER BY' => 'rc_timestamp DESC, rc_id DESC'
 132                                 ];
 133                         } else {
 134                                 $order = [ 'ORDER BY' => 'rc_timestamp DESC' ];
 135                         }
 136                 } else {
 137                         $order = [];
 138                 }
 139
 140                 if ( !$this->runMainQueryHook( $tables, $select, $conds, $query_options, $join_conds,
 141                         $opts )
 142                 ) {
 143                         return false;
 144                 }
 145
 146                 if ( $ns == NS_CATEGORY && !$showlinkedto ) {
 147                         // special handling for categories
 148                         // XXX: should try to make this less kludgy
 149                         $link_tables = [ 'categorylinks' ];
 150                         $showlinkedto = true;
 151                 } else {
 152                         // for now, always join on these tables; really should be configurable as in whatlinkshere
 153                         $link_tables = [ 'pagelinks', 'templatelinks' ];
 154                         // imagelinks only contains links to pages in NS_FILE
 155                         if ( $ns == NS_FILE || !$showlinkedto ) {
 156                                 $link_tables[] = 'imagelinks';
 157                         }
 158                 }
 159
 160                 if ( $id == 0 && !$showlinkedto ) {
 161                         return false; // nonexistent pages can't link to any pages
 162                 }
 163
 164                 // field name prefixes for all the various tables we might want to join with
 165                 $prefix = [
 166                         'pagelinks' => 'pl',
 167                         'templatelinks' => 'tl',
 168                         'categorylinks' => 'cl',
 169                         'imagelinks' => 'il'
 170                 ];
 171
 172                 $subsql = []; // SELECT statements to combine with UNION
 173
 174                 foreach ( $link_tables as $link_table ) {
 175                         $pfx = $prefix[$link_table];
 176
 177                         // imagelinks and categorylinks tables have no xx_namespace field,
 178                         // and have xx_to instead of xx_title
 179                         if ( $link_table == 'imagelinks' ) {
 180                                 $link_ns = NS_FILE;
 181                         } elseif ( $link_table == 'categorylinks' ) {
 182                                 $link_ns = NS_CATEGORY;
 183                         } else {
 184                                 $link_ns = 0;
 185                         }
 186
 187                         if ( $showlinkedto ) {
 188                                 // find changes to pages linking to this page
 189                                 if ( $link_ns ) {
 190                                         if ( $ns != $link_ns ) {
 191                                                 continue;
 192                                         } // should never happen, but check anyway
 193                                         $subconds = [ "{$pfx}_to" => $dbkey ];
 194                                 } else {
 195                                         $subconds = [ "{$pfx}_namespace" => $ns, "{$pfx}_title" => $dbkey ];
 196                                 }
 197                                 $subjoin = "rc_cur_id = {$pfx}_from";
 198                         } else {
 199                                 // find changes to pages linked from this page
 200                                 $subconds = [ "{$pfx}_from" => $id ];
 201                                 if ( $link_table == 'imagelinks' || $link_table == 'categorylinks' ) {
 202                                         $subconds["rc_namespace"] = $link_ns;
 203                                         $subjoin = "rc_title = {$pfx}_to";
 204                                 } else {
 205                                         $subjoin = [ "rc_namespace = {$pfx}_namespace", "rc_title = {$pfx}_title" ];
 206                                 }
 207                         }
 208
 209                         $query = $dbr->selectSQLText(
 210                                 array_merge( $tables, [ $link_table ] ),
 211                                 $select,
 212                                 $conds + $subconds,
 213                                 __METHOD__,
 214                                 $order + $query_options,
 215                                 $join_conds + [ $link_table => [ 'JOIN', $subjoin ] ]
 216                         );
 217
 218                         if ( $dbr->unionSupportsOrderAndLimit() ) {
 219                                 $query = $dbr->limitResult( $query, $limit );
 220                         }
 221
 222                         $subsql[] = $query;
 223                 }
 224
 225                 if ( count( $subsql ) == 0 ) {
 226                         return false; // should never happen
 227                 }
 228                 if ( count( $subsql ) == 1 && $dbr->unionSupportsOrderAndLimit() ) {
 229                         $sql = $subsql[0];
 230                 } else {
 231                         // need to resort and relimit after union
 232                         $sql = $dbr->unionQueries( $subsql, $dbr::UNION_DISTINCT ) .
 233                                 ' ORDER BY rc_timestamp DESC';
 234                         $sql = $dbr->limitResult( $sql, $limit, false );
 235                 }
 236
 237                 return $dbr->query( $sql, __METHOD__ );
 238         }
 239
 240         function setTopText( FormOptions $opts ) {
 241                 $target = $this->getTargetTitle();
 242                 if ( $target ) {
 243                         $this->getOutput()->addBacklinkSubtitle( $target );
 244                         $this->getSkin()->setRelevantTitle( $target );
 245                 }
 246         }
 247
 248         /**
 249          * Get options to be displayed in a form
 250          *
 251          * @param FormOptions $opts
 252          * @return array
 253          */
 254         function getExtraOptions( $opts ) {
 255                 $extraOpts = parent::getExtraOptions( $opts );
 256
 257                 $opts->consumeValues( [ 'showlinkedto', 'target' ] );
 258
 259                 $extraOpts['target'] = [ $this->msg( 'recentchangeslinked-page' )->escaped(),
 260                         Xml::input( 'target', 40, str_replace( '_', ' ', $opts['target'] ) ) .
 261                         Xml::check( 'showlinkedto', $opts['showlinkedto'], [ 'id' => 'showlinkedto' ] ) . ' ' .
 262                         Xml::label( $this->msg( 'recentchangeslinked-to' )->text(), 'showlinkedto' ) ];
 263
 264                 $this->addHelpLink( 'Help:Related changes' );
 265                 return $extraOpts;
 266         }
 267
 268         /**
 269          * @return Title
 270          */
 271         function getTargetTitle() {
 272                 if ( $this->rclTargetTitle === null ) {
 273                         $opts = $this->getOptions();
 274                         if ( isset( $opts['target'] ) && $opts['target'] !== '' ) {
 275                                 $this->rclTargetTitle = Title::newFromText( $opts['target'] );
 276                         } else {
 277                                 $this->rclTargetTitle = false;
 278                         }
 279                 }
 280
 281                 return $this->rclTargetTitle;
 282         }
 283
 284         /**
 285          * Return an array of subpages beginning with $search that this special page will accept.
 286          *
 287          * @param string $search Prefix to search for
 288          * @param int $limit Maximum number of results to return (usually 10)
 289          * @param int $offset Number of results to skip (usually 0)
 290          * @return string[] Matching subpages
 291          */
 292         public function prefixSearchSubpages( $search, $limit, $offset ) {
 293                 return $this->prefixSearchString( $search, $limit, $offset );
 294         }
 295
 296         protected function outputNoResults() {
 297                 $targetTitle = $this->getTargetTitle();
 298                 if ( $targetTitle === false ) {
 299                         $this->getOutput()->addHTML(
 300                                 Html::rawElement(
 301                                         'div',
 302                                         [ 'class' => 'mw-changeslist-empty mw-changeslist-notargetpage' ],
 303                                         $this->msg( 'recentchanges-notargetpage' )->parse()
 304                                 )
 305                         );
 306                 } elseif ( !$targetTitle || $targetTitle->isExternal() ) {
 307                         $this->getOutput()->addHTML(
 308                                 Html::rawElement(
 309                                         'div',
 310                                         [ 'class' => 'mw-changeslist-empty mw-changeslist-invalidtargetpage' ],
 311                                         $this->msg( 'allpagesbadtitle' )->parse()
 312                                 )
 313                         );
 314                 } else {
 315                         parent::outputNoResults();
 316                 }
 317         }
 318 }