includes/api/ApiQueryBacklinksprop.php

   1 <?php
   2 /**
   3  * API module to handle links table back-queries
   4  *
   5  * Created on Aug 19, 2014
   6  *
   7  * Copyright © 2014 Brad Jorsch <bjorsch@wikimedia.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  22  * http://www.gnu.org/copyleft/gpl.html
  23  *
  24  * @file
  25  * @since 1.24
  26  */
  27
  28 /**
  29  * This implements prop=redirects, prop=linkshere, prop=catmembers,
  30  * prop=transcludedin, and prop=fileusage
  31  *
  32  * @ingroup API
  33  * @since 1.24
  34  */
  35 class ApiQueryBacklinksprop extends ApiQueryGeneratorBase {
  36
  37         // Data for the various modules implemented by this class
  38         private static $settings = array(
  39                 'redirects' => array(
  40                         'code' => 'rd',
  41                         'prefix' => 'rd',
  42                         'linktable' => 'redirect',
  43                         'props' => array(
  44                                 'fragment',
  45                         ),
  46                         'showredirects' => false,
  47                         'show' => array(
  48                                 'fragment',
  49                                 '!fragment',
  50                         ),
  51                 ),
  52                 'linkshere' => array(
  53                         'code' => 'lh',
  54                         'prefix' => 'pl',
  55                         'linktable' => 'pagelinks',
  56                         'from_namespace' => true,
  57                         'showredirects' => true,
  58                 ),
  59                 'transcludedin' => array(
  60                         'code' => 'ti',
  61                         'prefix' => 'tl',
  62                         'linktable' => 'templatelinks',
  63                         'from_namespace' => true,
  64                         'showredirects' => true,
  65                 ),
  66                 'fileusage' => array(
  67                         'code' => 'fu',
  68                         'prefix' => 'il',
  69                         'linktable' => 'imagelinks',
  70                         'from_namespace' => true,
  71                         'to_namespace' => NS_FILE,
  72                         'exampletitle' => 'File:Example.jpg',
  73                         'showredirects' => true,
  74                 ),
  75         );
  76
  77         public function __construct( ApiQuery $query, $moduleName ) {
  78                 parent::__construct( $query, $moduleName, self::$settings[$moduleName]['code'] );
  79         }
  80
  81         public function execute() {
  82                 $this->run();
  83         }
  84
  85         public function executeGenerator( $resultPageSet ) {
  86                 $this->run( $resultPageSet );
  87         }
  88
  89         /**
  90          * @param ApiPageSet $resultPageSet
  91          */
  92         private function run( ApiPageSet $resultPageSet = null ) {
  93                 $settings = self::$settings[$this->getModuleName()];
  94
  95                 $db = $this->getDB();
  96                 $params = $this->extractRequestParams();
  97                 $prop = array_flip( $params['prop'] );
  98                 $emptyString = $db->addQuotes( '' );
  99
 100                 $pageSet = $this->getPageSet();
 101                 $titles = $pageSet->getGoodAndMissingTitles();
 102                 $map = $pageSet->getGoodAndMissingTitlesByNamespace();
 103
 104                 // Determine our fields to query on
 105                 $p = $settings['prefix'];
 106                 $hasNS = !isset( $settings['to_namespace'] );
 107                 if ( $hasNS ) {
 108                         $bl_namespace = "{$p}_namespace";
 109                         $bl_title = "{$p}_title";
 110                 } else {
 111                         $bl_namespace = $settings['to_namespace'];
 112                         $bl_title = "{$p}_to";
 113
 114                         $titles = array_filter( $titles, function ( $t ) use ( $bl_namespace ) {
 115                                 return $t->getNamespace() === $bl_namespace;
 116                         } );
 117                         $map = array_intersect_key( $map, array( $bl_namespace => true ) );
 118                 }
 119                 $bl_from = "{$p}_from";
 120
 121                 if ( !$titles ) {
 122                         return; // nothing to do
 123                 }
 124
 125                 // Figure out what we're sorting by, and add associated WHERE clauses.
 126                 // MySQL's query planner screws up if we include a field in ORDER BY
 127                 // when it's constant in WHERE, so we have to test that for each field.
 128                 $sortby = array();
 129                 if ( $hasNS && count( $map ) > 1 ) {
 130                         $sortby[$bl_namespace] = 'ns';
 131                 }
 132                 $theTitle = null;
 133                 foreach ( $map as $nsTitles ) {
 134                         reset( $nsTitles );
 135                         $key = key( $nsTitles );
 136                         if ( $theTitle === null ) {
 137                                 $theTitle = $key;
 138                         }
 139                         if ( count( $nsTitles ) > 1 || $key !== $theTitle ) {
 140                                 $sortby[$bl_title] = 'title';
 141                                 break;
 142                         }
 143                 }
 144                 $miser_ns = null;
 145                 if ( $params['namespace'] !== null ) {
 146                         if ( empty( $settings['from_namespace'] ) && $this->getConfig()->get( 'MiserMode' ) ) {
 147                                 $miser_ns = $params['namespace'];
 148                         } else {
 149                                 $this->addWhereFld( "{$p}_from_namespace", $params['namespace'] );
 150                                 if ( !empty( $settings['from_namespace'] ) && count( $params['namespace'] ) > 1 ) {
 151                                         $sortby["{$p}_from_namespace"] = 'int';
 152                                 }
 153                         }
 154                 }
 155                 $sortby[$bl_from] = 'int';
 156
 157                 // Now use the $sortby to figure out the continuation
 158                 if ( !is_null( $params['continue'] ) ) {
 159                         $cont = explode( '|', $params['continue'] );
 160                         $this->dieContinueUsageIf( count( $cont ) != count( $sortby ) );
 161                         $where = '';
 162                         $i = count( $sortby ) - 1;
 163                         $cont_ns = 0;
 164                         $cont_title = '';
 165                         foreach ( array_reverse( $sortby, true ) as $field => $type ) {
 166                                 $v = $cont[$i];
 167                                 switch ( $type ) {
 168                                         case 'ns':
 169                                                 $cont_ns = (int)$v;
 170                                                 /* fall through */
 171                                         case 'int':
 172                                                 $v = (int)$v;
 173                                                 $this->dieContinueUsageIf( $v != $cont[$i] );
 174                                                 break;
 175
 176                                         case 'title':
 177                                                 $cont_title = $v;
 178                                                 /* fall through */
 179                                         default:
 180                                                 $v = $db->addQuotes( $v );
 181                                                 break;
 182                                 }
 183
 184                                 if ( $where === '' ) {
 185                                         $where = "$field >= $v";
 186                                 } else {
 187                                         $where = "$field > $v OR ($field = $v AND ($where))";
 188                                 }
 189
 190                                 $i--;
 191                         }
 192                         $this->addWhere( $where );
 193                 }
 194
 195                 // Populate the rest of the query
 196                 $this->addTables( array( $settings['linktable'], 'page' ) );
 197                 $this->addWhere( "$bl_from = page_id" );
 198
 199                 if ( $this->getModuleName() === 'redirects' ) {
 200                         $this->addWhere( "rd_interwiki = $emptyString OR rd_interwiki IS NULL" );
 201                 }
 202
 203                 $this->addFields( array_keys( $sortby ) );
 204                 $this->addFields( array( 'bl_namespace' => $bl_namespace, 'bl_title' => $bl_title ) );
 205                 if ( is_null( $resultPageSet ) ) {
 206                         $fld_pageid = isset( $prop['pageid'] );
 207                         $fld_title = isset( $prop['title'] );
 208                         $fld_redirect = isset( $prop['redirect'] );
 209
 210                         $this->addFieldsIf( 'page_id', $fld_pageid );
 211                         $this->addFieldsIf( array( 'page_title', 'page_namespace' ), $fld_title );
 212                         $this->addFieldsIf( 'page_is_redirect', $fld_redirect );
 213
 214                         // prop=redirects
 215                         $fld_fragment = isset( $prop['fragment'] );
 216                         $this->addFieldsIf( 'rd_fragment', $fld_fragment );
 217                 } else {
 218                         $this->addFields( $resultPageSet->getPageTableFields() );
 219                 }
 220
 221                 $this->addFieldsIf( 'page_namespace', $miser_ns !== null );
 222
 223                 if ( $hasNS ) {
 224                         $lb = new LinkBatch( $titles );
 225                         $this->addWhere( $lb->constructSet( $p, $db ) );
 226                 } else {
 227                         $where = array();
 228                         foreach ( $titles as $t ) {
 229                                 if ( $t->getNamespace() == $bl_namespace ) {
 230                                         $where[] = "$bl_title = " . $db->addQuotes( $t->getDBkey() );
 231                                 }
 232                         }
 233                         $this->addWhere( $db->makeList( $where, LIST_OR ) );
 234                 }
 235
 236                 if ( $params['show'] !== null ) {
 237                         // prop=redirects only
 238                         $show = array_flip( $params['show'] );
 239                         if ( isset( $show['fragment'] ) && isset( $show['!fragment'] ) ||
 240                                 isset( $show['redirect'] ) && isset( $show['!redirect'] )
 241                         ) {
 242                                 $this->dieUsageMsg( 'show' );
 243                         }
 244                         $this->addWhereIf( "rd_fragment != $emptyString", isset( $show['fragment'] ) );
 245                         $this->addWhereIf(
 246                                 "rd_fragment = $emptyString OR rd_fragment IS NULL",
 247                                 isset( $show['!fragment'] )
 248                         );
 249                         $this->addWhereIf( array( 'page_is_redirect' => 1 ), isset( $show['redirect'] ) );
 250                         $this->addWhereIf( array( 'page_is_redirect' => 0 ), isset( $show['!redirect'] ) );
 251                 }
 252
 253                 // Override any ORDER BY from above with what we calculated earlier.
 254                 $this->addOption( 'ORDER BY', array_keys( $sortby ) );
 255
 256                 $this->addOption( 'LIMIT', $params['limit'] + 1 );
 257
 258                 $res = $this->select( __METHOD__ );
 259
 260                 if ( is_null( $resultPageSet ) ) {
 261                         $count = 0;
 262                         foreach ( $res as $row ) {
 263                                 if ( ++$count > $params['limit'] ) {
 264                                         // We've reached the one extra which shows that
 265                                         // there are additional pages to be had. Stop here...
 266                                         $this->setContinue( $row, $sortby );
 267                                         break;
 268                                 }
 269
 270                                 if ( $miser_ns !== null && !in_array( $row->page_namespace, $miser_ns ) ) {
 271                                         // Miser mode namespace check
 272                                         continue;
 273                                 }
 274
 275                                 // Get the ID of the current page
 276                                 $id = $map[$row->bl_namespace][$row->bl_title];
 277
 278                                 $vals = array();
 279                                 if ( $fld_pageid ) {
 280                                         $vals['pageid'] = $row->page_id;
 281                                 }
 282                                 if ( $fld_title ) {
 283                                         ApiQueryBase::addTitleInfo( $vals,
 284                                                 Title::makeTitle( $row->page_namespace, $row->page_title )
 285                                         );
 286                                 }
 287                                 if ( $fld_fragment && $row->rd_fragment !== null && $row->rd_fragment !== '' ) {
 288                                         $vals['fragment'] = $row->rd_fragment;
 289                                 }
 290                                 if ( $fld_redirect && $row->page_is_redirect ) {
 291                                         $vals['redirect'] = '';
 292                                 }
 293                                 $fit = $this->addPageSubItem( $id, $vals );
 294                                 if ( !$fit ) {
 295                                         $this->setContinue( $row, $sortby );
 296                                         break;
 297                                 }
 298                         }
 299                 } else {
 300                         $titles = array();
 301                         $count = 0;
 302                         foreach ( $res as $row ) {
 303                                 if ( ++$count > $params['limit'] ) {
 304                                         // We've reached the one extra which shows that
 305                                         // there are additional pages to be had. Stop here...
 306                                         $this->setContinue( $row, $sortby );
 307                                         break;
 308                                 }
 309                                 $titles[] = Title::makeTitle( $row->page_namespace, $row->page_title );
 310                         }
 311                         $resultPageSet->populateFromTitles( $titles );
 312                 }
 313         }
 314
 315         private function setContinue( $row, $sortby ) {
 316                 $cont = array();
 317                 foreach ( $sortby as $field => $v ) {
 318                         $cont[] = $row->$field;
 319                 }
 320                 $this->setContinueEnumParameter( 'continue', join( '|', $cont ) );
 321         }
 322
 323         public function getCacheMode( $params ) {
 324                 return 'public';
 325         }
 326
 327         public function getAllowedParams() {
 328                 $settings = self::$settings[$this->getModuleName()];
 329
 330                 $ret = array(
 331                         'prop' => array(
 332                                 ApiBase::PARAM_TYPE => array(
 333                                         'pageid',
 334                                         'title',
 335                                 ),
 336                                 ApiBase::PARAM_ISMULTI => true,
 337                                 ApiBase::PARAM_DFLT => 'pageid|title',
 338                         ),
 339                         'namespace' => array(
 340                                 ApiBase::PARAM_ISMULTI => true,
 341                                 ApiBase::PARAM_TYPE => 'namespace',
 342                         ),
 343                         'show' => null, // Will be filled/removed below
 344                         'limit' => array(
 345                                 ApiBase::PARAM_DFLT => 10,
 346                                 ApiBase::PARAM_TYPE => 'limit',
 347                                 ApiBase::PARAM_MIN => 1,
 348                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 349                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 350                         ),
 351                         'continue' => array(
 352                                 ApiBase::PARAM_HELP_MSG => 'api-help-param-continue',
 353                         ),
 354                 );
 355
 356                 if ( empty( $settings['from_namespace'] ) && $this->getConfig()->get( 'MiserMode' ) ) {
 357                         $ret['namespace'][ApiBase::PARAM_HELP_MSG_APPEND] = array(
 358                                 'api-help-param-limited-in-miser-mode',
 359                         );
 360                 }
 361
 362                 if ( !empty( $settings['showredirects'] ) ) {
 363                         $ret['prop'][ApiBase::PARAM_TYPE][] = 'redirect';
 364                         $ret['prop'][ApiBase::PARAM_DFLT] .= '|redirect';
 365                 }
 366                 if ( isset( $settings['props'] ) ) {
 367                         $ret['prop'][ApiBase::PARAM_TYPE] = array_merge(
 368                                 $ret['prop'][ApiBase::PARAM_TYPE], $settings['props']
 369                         );
 370                 }
 371
 372                 $show = array();
 373                 if ( !empty( $settings['showredirects'] ) ) {
 374                         $show[] = 'redirect';
 375                         $show[] = '!redirect';
 376                 }
 377                 if ( isset( $settings['show'] ) ) {
 378                         $show = array_merge( $show, $settings['show'] );
 379                 }
 380                 if ( $show ) {
 381                         $ret['show'] = array(
 382                                 ApiBase::PARAM_TYPE => $show,
 383                                 ApiBase::PARAM_ISMULTI => true,
 384                         );
 385                 } else {
 386                         unset( $ret['show'] );
 387                 }
 388
 389                 return $ret;
 390         }
 391
 392         protected function getExamplesMessages() {
 393                 $settings = self::$settings[$this->getModuleName()];
 394                 $name = $this->getModuleName();
 395                 $path = $this->getModulePath();
 396                 $title = isset( $settings['exampletitle'] ) ? $settings['exampletitle'] : 'Main Page';
 397                 $etitle = rawurlencode( $title );
 398
 399                 return array(
 400                         "action=query&prop={$name}&titles={$etitle}"
 401                                 => "apihelp-$path-example-simple",
 402                         "action=query&generator={$name}&titles={$etitle}&prop=info"
 403                                 => "apihelp-$path-example-generator",
 404                 );
 405         }
 406
 407         public function getHelpUrls() {
 408                 $name = $this->getModuleName();
 409                 $prefix = $this->getModulePrefix();
 410                 return "https://www.mediawiki.org/wiki/API:Properties#{$name}_.2F_{$prefix}";
 411         }
 412 }