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         protected $rclTarget;
  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                 $this->rclTarget = $par;
  50         }
  51
  52         /**
  53          * @inheritDoc
  54          */
  55         protected function doMainQuery( $tables, $select, $conds, $query_options,
  56                 $join_conds, FormOptions $opts
  57         ) {
  58                 $target = $opts['target'];
  59                 $showlinkedto = $opts['showlinkedto'];
  60                 $limit = $opts['limit'];
  61
  62                 if ( $target === '' ) {
  63                         return false;
  64                 }
  65                 $outputPage = $this->getOutput();
  66                 $title = Title::newFromText( $target );
  67                 if ( !$title || $title->isExternal() ) {
  68                         $outputPage->addHTML(
  69                                 Html::errorBox( $this->msg( 'allpagesbadtitle' )->parse() )
  70                         );
  71
  72                         return false;
  73                 }
  74
  75                 $outputPage->setPageTitle( $this->msg( 'recentchangeslinked-title', $title->getPrefixedText() ) );
  76
  77                 /*
  78                  * Ordinary links are in the pagelinks table, while transclusions are
  79                  * in the templatelinks table, categorizations in categorylinks and
  80                  * image use in imagelinks.  We need to somehow combine all these.
  81                  * Special:Whatlinkshere does this by firing multiple queries and
  82                  * merging the results, but the code we inherit from our parent class
  83                  * expects only one result set so we use UNION instead.
  84                  */
  85
  86                 $dbr = wfGetDB( DB_REPLICA, 'recentchangeslinked' );
  87                 $id = $title->getArticleID();
  88                 $ns = $title->getNamespace();
  89                 $dbkey = $title->getDBkey();
  90
  91                 $rcQuery = RecentChange::getQueryInfo();
  92                 $tables = array_merge( $tables, $rcQuery['tables'] );
  93                 $select = array_merge( $rcQuery['fields'], $select );
  94                 $join_conds = array_merge( $join_conds, $rcQuery['joins'] );
  95
  96                 // left join with watchlist table to highlight watched rows
  97                 $uid = $this->getUser()->getId();
  98                 if ( $uid && $this->getUser()->isAllowed( 'viewmywatchlist' ) ) {
  99                         $tables[] = 'watchlist';
 100                         $select[] = 'wl_user';
 101                         $join_conds['watchlist'] = [ 'LEFT JOIN', [
 102                                 'wl_user' => $uid,
 103                                 'wl_title=rc_title',
 104                                 'wl_namespace=rc_namespace'
 105                         ] ];
 106                 }
 107
 108                 // JOIN on page, used for 'last revision' filter highlight
 109                 $tables[] = 'page';
 110                 $join_conds['page'] = [ 'LEFT JOIN', 'rc_cur_id=page_id' ];
 111                 $select[] = 'page_latest';
 112
 113                 $tagFilter = $opts['tagfilter'] ? explode( '|', $opts['tagfilter'] ) : [];
 114                 ChangeTags::modifyDisplayQuery(
 115                         $tables,
 116                         $select,
 117                         $conds,
 118                         $join_conds,
 119                         $query_options,
 120                         $tagFilter
 121                 );
 122
 123                 if ( $dbr->unionSupportsOrderAndLimit() ) {
 124                         if ( count( $tagFilter ) > 1 ) {
 125                                 // ChangeTags::modifyDisplayQuery() will have added DISTINCT.
 126                                 // To prevent this from causing query performance problems, we need to add
 127                                 // a GROUP BY, and add rc_id to the ORDER BY.
 128                                 $order = [
 129                                         'GROUP BY' => 'rc_timestamp, rc_id',
 130                                         'ORDER BY' => 'rc_timestamp DESC, rc_id DESC'
 131                                 ];
 132                         } else {
 133                                 $order = [ 'ORDER BY' => 'rc_timestamp DESC' ];
 134                         }
 135                 } else {
 136                         $order = [];
 137                 }
 138
 139                 if ( !$this->runMainQueryHook( $tables, $select, $conds, $query_options, $join_conds,
 140                         $opts )
 141                 ) {
 142                         return false;
 143                 }
 144
 145                 if ( $ns == NS_CATEGORY && !$showlinkedto ) {
 146                         // special handling for categories
 147                         // XXX: should try to make this less kludgy
 148                         $link_tables = [ 'categorylinks' ];
 149                         $showlinkedto = true;
 150                 } else {
 151                         // for now, always join on these tables; really should be configurable as in whatlinkshere
 152                         $link_tables = [ 'pagelinks', 'templatelinks' ];
 153                         // imagelinks only contains links to pages in NS_FILE
 154                         if ( $ns == NS_FILE || !$showlinkedto ) {
 155                                 $link_tables[] = 'imagelinks';
 156                         }
 157                 }
 158
 159                 if ( $id == 0 && !$showlinkedto ) {
 160                         return false; // nonexistent pages can't link to any pages
 161                 }
 162
 163                 // field name prefixes for all the various tables we might want to join with
 164                 $prefix = [
 165                         'pagelinks' => 'pl',
 166                         'templatelinks' => 'tl',
 167                         'categorylinks' => 'cl',
 168                         'imagelinks' => 'il'
 169                 ];
 170
 171                 $subsql = []; // SELECT statements to combine with UNION
 172
 173                 foreach ( $link_tables as $link_table ) {
 174                         $pfx = $prefix[$link_table];
 175
 176                         // imagelinks and categorylinks tables have no xx_namespace field,
 177                         // and have xx_to instead of xx_title
 178                         if ( $link_table == 'imagelinks' ) {
 179                                 $link_ns = NS_FILE;
 180                         } elseif ( $link_table == 'categorylinks' ) {
 181                                 $link_ns = NS_CATEGORY;
 182                         } else {
 183                                 $link_ns = 0;
 184                         }
 185
 186                         if ( $showlinkedto ) {
 187                                 // find changes to pages linking to this page
 188                                 if ( $link_ns ) {
 189                                         if ( $ns != $link_ns ) {
 190                                                 continue;
 191                                         } // should never happen, but check anyway
 192                                         $subconds = [ "{$pfx}_to" => $dbkey ];
 193                                 } else {
 194                                         $subconds = [ "{$pfx}_namespace" => $ns, "{$pfx}_title" => $dbkey ];
 195                                 }
 196                                 $subjoin = "rc_cur_id = {$pfx}_from";
 197                         } else {
 198                                 // find changes to pages linked from this page
 199                                 $subconds = [ "{$pfx}_from" => $id ];
 200                                 if ( $link_table == 'imagelinks' || $link_table == 'categorylinks' ) {
 201                                         $subconds["rc_namespace"] = $link_ns;
 202                                         $subjoin = "rc_title = {$pfx}_to";
 203                                 } else {
 204                                         $subjoin = [ "rc_namespace = {$pfx}_namespace", "rc_title = {$pfx}_title" ];
 205                                 }
 206                         }
 207
 208                         $query = $dbr->selectSQLText(
 209                                 array_merge( $tables, [ $link_table ] ),
 210                                 $select,
 211                                 $conds + $subconds,
 212                                 __METHOD__,
 213                                 $order + $query_options,
 214                                 $join_conds + [ $link_table => [ 'INNER JOIN', $subjoin ] ]
 215                         );
 216
 217                         if ( $dbr->unionSupportsOrderAndLimit() ) {
 218                                 $query = $dbr->limitResult( $query, $limit );
 219                         }
 220
 221                         $subsql[] = $query;
 222                 }
 223
 224                 if ( count( $subsql ) == 0 ) {
 225                         return false; // should never happen
 226                 }
 227                 if ( count( $subsql ) == 1 && $dbr->unionSupportsOrderAndLimit() ) {
 228                         $sql = $subsql[0];
 229                 } else {
 230                         // need to resort and relimit after union
 231                         $sql = $dbr->unionQueries( $subsql, false ) . ' ORDER BY rc_timestamp DESC';
 232                         $sql = $dbr->limitResult( $sql, $limit, false );
 233                 }
 234
 235                 $res = $dbr->query( $sql, __METHOD__ );
 236
 237                 if ( $res->numRows() == 0 ) {
 238                         $this->mResultEmpty = true;
 239                 }
 240
 241                 return $res;
 242         }
 243
 244         function setTopText( FormOptions $opts ) {
 245                 $target = $this->getTargetTitle();
 246                 if ( $target ) {
 247                         $this->getOutput()->addBacklinkSubtitle( $target );
 248                         $this->getSkin()->setRelevantTitle( $target );
 249                 }
 250         }
 251
 252         /**
 253          * Get options to be displayed in a form
 254          *
 255          * @param FormOptions $opts
 256          * @return array
 257          */
 258         function getExtraOptions( $opts ) {
 259                 $extraOpts = parent::getExtraOptions( $opts );
 260
 261                 $opts->consumeValues( [ 'showlinkedto', 'target' ] );
 262
 263                 $extraOpts['target'] = [ $this->msg( 'recentchangeslinked-page' )->escaped(),
 264                         Xml::input( 'target', 40, str_replace( '_', ' ', $opts['target'] ) ) .
 265                         Xml::check( 'showlinkedto', $opts['showlinkedto'], [ 'id' => 'showlinkedto' ] ) . ' ' .
 266                         Xml::label( $this->msg( 'recentchangeslinked-to' )->text(), 'showlinkedto' ) ];
 267
 268                 $this->addHelpLink( 'Help:Related changes' );
 269                 return $extraOpts;
 270         }
 271
 272         /**
 273          * @return Title
 274          */
 275         function getTargetTitle() {
 276                 if ( $this->rclTargetTitle === null ) {
 277                         $opts = $this->getOptions();
 278                         if ( isset( $opts['target'] ) && $opts['target'] !== '' ) {
 279                                 $this->rclTargetTitle = Title::newFromText( $opts['target'] );
 280                         } else {
 281                                 $this->rclTargetTitle = false;
 282                         }
 283                 }
 284
 285                 return $this->rclTargetTitle;
 286         }
 287
 288         /**
 289          * Return an array of subpages beginning with $search that this special page will accept.
 290          *
 291          * @param string $search Prefix to search for
 292          * @param int $limit Maximum number of results to return (usually 10)
 293          * @param int $offset Number of results to skip (usually 0)
 294          * @return string[] Matching subpages
 295          */
 296         public function prefixSearchSubpages( $search, $limit, $offset ) {
 297                 return $this->prefixSearchString( $search, $limit, $offset );
 298         }
 299
 300         /**
 301          * Get a self-referential title object
 302          * with consideration to the given subpage.
 303          *
 304          * @param string|bool $subpage
 305          * @return Title
 306          * @since 1.23
 307          */
 308         public function getPageTitle( $subpage = false ) {
 309                 $subpage = $subpage ? $subpage : $this->rclTarget;
 310
 311                 return parent::getPageTitle( $subpage );
 312         }
 313
 314         protected function outputNoResults() {
 315                 if ( $this->getTargetTitle() === false ) {
 316                         $this->getOutput()->addHTML(
 317                                 '<div class="mw-changeslist-notargetpage">' .
 318                                 $this->msg( 'recentchanges-notargetpage' )->parse() .
 319                                 '</div>'
 320                         );
 321                 } else {
 322                         parent::outputNoResults();
 323                 }
 324         }
 325 }