includes/api/ApiQueryLangLinks.php

   1 <?php
   2 /**
   3  *
   4  *
   5  * Created on May 13, 2007
   6  *
   7  * Copyright © 2006 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
   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  */
  26
  27 /**
  28  * A query module to list all langlinks (links to correspanding foreign language pages).
  29  *
  30  * @ingroup API
  31  */
  32 class ApiQueryLangLinks extends ApiQueryBase {
  33
  34         public function __construct( $query, $moduleName ) {
  35                 parent::__construct( $query, $moduleName, 'll' );
  36         }
  37
  38         public function execute() {
  39                 if ( $this->getPageSet()->getGoodTitleCount() == 0 ) {
  40                         return;
  41                 }
  42
  43                 $params = $this->extractRequestParams();
  44
  45                 if ( isset( $params['title'] ) && !isset( $params['lang'] ) ) {
  46                         $this->dieUsageMsg( array( 'missingparam', 'lang' ) );
  47                 }
  48
  49                 $this->addFields( array(
  50                         'll_from',
  51                         'll_lang',
  52                         'll_title'
  53                 ) );
  54
  55                 $this->addTables( 'langlinks' );
  56                 $this->addWhereFld( 'll_from', array_keys( $this->getPageSet()->getGoodTitles() ) );
  57                 if ( !is_null( $params['continue'] ) ) {
  58                         $cont = explode( '|', $params['continue'] );
  59                         if ( count( $cont ) != 2 ) {
  60                                 $this->dieUsage( 'Invalid continue param. You should pass the ' .
  61                                         'original value returned by the previous query', '_badcontinue' );
  62                         }
  63                         $op = $params['dir'] == 'descending' ? '<' : '>';
  64                         $llfrom = intval( $cont[0] );
  65                         $lllang = $this->getDB()->addQuotes( $cont[1] );
  66                         $this->addWhere(
  67                                 "ll_from $op $llfrom OR " .
  68                                 "(ll_from = $llfrom AND " .
  69                                 "ll_lang $op= $lllang)"
  70                         );
  71                 }
  72
  73                         $sort = ( $params['dir'] == 'descending' ? ' DESC' : '' );
  74                         if ( isset( $params['lang'] ) ) {
  75                         $this->addWhereFld( 'll_lang', $params['lang'] );
  76                         if ( isset( $params['title'] ) ) {
  77                                 $this->addWhereFld( 'll_title', $params['title'] );
  78                                 $this->addOption( 'ORDER BY', 'll_from' . $sort );
  79                         } else {
  80                                 $this->addOption( 'ORDER BY', array(
  81                                                         'll_title' . $sort,
  82                                                         'll_from' . $sort
  83                                 ));
  84                         }
  85                 } else {
  86                         // Don't order by ll_from if it's constant in the WHERE clause
  87                         if ( count( $this->getPageSet()->getGoodTitles() ) == 1 ) {
  88                                 $this->addOption( 'ORDER BY', 'll_lang' . $sort );
  89                         } else {
  90                                 $this->addOption( 'ORDER BY', array(
  91                                                         'll_from' . $sort,
  92                                                         'll_lang' . $sort
  93                                 ));
  94                         }
  95                 }
  96
  97                 $this->addOption( 'LIMIT', $params['limit'] + 1 );
  98                 $res = $this->select( __METHOD__ );
  99
 100                 $count = 0;
 101                 foreach ( $res as $row ) {
 102                         if ( ++$count > $params['limit'] ) {
 103                                 // We've reached the one extra which shows that
 104                                 // there are additional pages to be had. Stop here...
 105                                 $this->setContinueEnumParameter( 'continue', "{$row->ll_from}|{$row->ll_lang}" );
 106                                 break;
 107                         }
 108                         $entry = array( 'lang' => $row->ll_lang );
 109                         if ( $params['url'] ) {
 110                                 $title = Title::newFromText( "{$row->ll_lang}:{$row->ll_title}" );
 111                                 if ( $title ) {
 112                                         $entry['url'] = wfExpandUrl( $title->getFullURL(), PROTO_CURRENT );
 113                                 }
 114                         }
 115                         ApiResult::setContent( $entry, $row->ll_title );
 116                         $fit = $this->addPageSubItem( $row->ll_from, $entry );
 117                         if ( !$fit ) {
 118                                 $this->setContinueEnumParameter( 'continue', "{$row->ll_from}|{$row->ll_lang}" );
 119                                 break;
 120                         }
 121                 }
 122         }
 123
 124         public function getCacheMode( $params ) {
 125                 return 'public';
 126         }
 127
 128         public function getAllowedParams() {
 129                 return array(
 130                         'limit' => array(
 131                                 ApiBase::PARAM_DFLT => 10,
 132                                 ApiBase::PARAM_TYPE => 'limit',
 133                                 ApiBase::PARAM_MIN => 1,
 134                                 ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
 135                                 ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
 136                         ),
 137                         'continue' => null,
 138                         'url' => false,
 139                         'lang' => null,
 140                         'title' => null,
 141                         'dir' => array(
 142                                 ApiBase::PARAM_DFLT => 'ascending',
 143                                 ApiBase::PARAM_TYPE => array(
 144                                         'ascending',
 145                                         'descending'
 146                                 )
 147                         ),
 148                 );
 149         }
 150
 151         public function getParamDescription() {
 152                 return array(
 153                         'limit' => 'How many langlinks to return',
 154                         'continue' => 'When more results are available, use this to continue',
 155                         'url' => 'Whether to get the full URL',
 156                         'lang' => 'Language code',
 157                         'title' => "Link to search for. Must be used with {$this->getModulePrefix()}lang",
 158                         'dir' => 'The direction in which to list',
 159                 );
 160         }
 161
 162         public function getResultProperties() {
 163                 return array(
 164                         '' => array(
 165                                 'lang' => 'string',
 166                                 'url' => array(
 167                                         ApiBase::PROP_TYPE => 'string',
 168                                         ApiBase::PROP_NULLABLE => true
 169                                 ),
 170                                 '*' => 'string'
 171                         )
 172                 );
 173         }
 174
 175         public function getDescription() {
 176                 return 'Returns all interlanguage links from the given page(s)';
 177         }
 178
 179         public function getPossibleErrors() {
 180                 return array_merge( parent::getPossibleErrors(), array(
 181                         array( 'missingparam', 'lang' ),
 182                         array( 'code' => '_badcontinue', 'info' => 'Invalid continue param. You should pass the original value returned by the previous query' ),
 183                 ) );
 184         }
 185
 186         public function getExamples() {
 187                 return array(
 188                         'api.php?action=query&prop=langlinks&titles=Main%20Page&redirects=' => 'Get interlanguage links from the [[Main Page]]',
 189                 );
 190         }
 191
 192         public function getHelpUrls() {
 193                 return 'https://www.mediawiki.org/wiki/API:Properties#langlinks_.2F_ll';
 194         }
 195
 196         public function getVersion() {
 197                 return __CLASS__ . ': $Id$';
 198         }
 199 }