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