includes/api/ApiQueryCategoryMembers.php

   1 <?php
   2
   3 /*
   4  * Created on June 14, 2007
   5  *
   6  * API for MediaWiki 1.8+
   7  *
   8  * Copyright (C) 2006 Yuri Astrakhan <Firstname><Lastname>@gmail.com
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License along
  21  * with this program; if not, write to the Free Software Foundation, Inc.,
  22  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  * http://www.gnu.org/copyleft/gpl.html
  24  */
  25
  26 if (!defined('MEDIAWIKI')) {
  27         // Eclipse helper - will be ignored in production
  28         require_once ("ApiQueryBase.php");
  29 }
  30
  31 /**
  32  * A query module to enumerate pages that belong to a category.
  33  *
  34  * @addtogroup API
  35  */
  36 class ApiQueryCategoryMembers extends ApiQueryGeneratorBase {
  37
  38         public function __construct($query, $moduleName) {
  39                 parent :: __construct($query, $moduleName, 'cm');
  40         }
  41
  42         public function execute() {
  43                 $this->run();
  44         }
  45
  46         public function executeGenerator($resultPageSet) {
  47                 $this->run($resultPageSet);
  48         }
  49
  50         private function run($resultPageSet = null) {
  51
  52                 $params = $this->extractRequestParams();
  53
  54                 if (is_null($params['category'])) {
  55                         if (is_null($params['title']))
  56                                 $this->dieUsage("Either the cmcategory or the cmtitle parameter is required", 'notitle');
  57                         else
  58                                 $categoryTitle = Title::newFromText($params['title']);
  59                 } else if(is_null($params['title']))
  60                         $categoryTitle = Title::makeTitleSafe(NS_CATEGORY, $params['category']);
  61                 else
  62                         $this->dieUsage("The category and title parameters can't be used together", 'titleandcategory');
  63
  64                 if ( is_null( $categoryTitle ) || $categoryTitle->getNamespace() != NS_CATEGORY )
  65                         $this->dieUsage("The category name you entered is not valid", 'invalidcategory');
  66
  67                 $prop = array_flip($params['prop']);
  68                 $fld_ids = isset($prop['ids']);
  69                 $fld_title = isset($prop['title']);
  70                 $fld_sortkey = isset($prop['sortkey']);
  71                 $fld_timestamp = isset($prop['timestamp']);
  72
  73                 if (is_null($resultPageSet)) {
  74                         $this->addFields(array('cl_from', 'cl_sortkey', 'page_namespace', 'page_title'));
  75                         $this->addFieldsIf('page_id', $fld_ids);
  76                 } else {
  77                         $this->addFields($resultPageSet->getPageTableFields()); // will include page_ id, ns, title
  78                         $this->addFields(array('cl_from', 'cl_sortkey'));
  79                 }
  80
  81                 $this->addFieldsIf('cl_timestamp', $fld_timestamp);
  82                 $this->addTables(array('page','categorylinks'));        // must be in this order for 'USE INDEX'
  83                                                                         // Not needed after bug 10280 is applied to servers
  84                 if($params['sort'] == 'timestamp')
  85                 {
  86                         $this->addOption('USE INDEX', 'cl_timestamp');
  87                         $this->addOption('ORDER BY', 'cl_to, cl_timestamp' . ($params['dir'] == 'desc' ? ' DESC' : ''));
  88                 }
  89                 else
  90                 {
  91                         $this->addOption('USE INDEX', 'cl_sortkey');
  92                         $this->addOption('ORDER BY', 'cl_to, cl_sortkey' . ($params['dir'] == 'desc' ? ' DESC' : '') . ', cl_from');
  93                 }
  94
  95                 $this->addWhere('cl_from=page_id');
  96                 $this->setContinuation($params['continue']);
  97                 $this->addWhereFld('cl_to', $categoryTitle->getDBkey());
  98                 $this->addWhereFld('page_namespace', $params['namespace']);
  99
 100                 $limit = $params['limit'];
 101                 $this->addOption('LIMIT', $limit +1);
 102
 103                 $db = $this->getDB();
 104
 105                 $data = array ();
 106                 $count = 0;
 107                 $lastSortKey = null;
 108                 $res = $this->select(__METHOD__);
 109                 while ($row = $db->fetchObject($res)) {
 110                         if (++ $count > $limit) {
 111                                 // We've reached the one extra which shows that there are additional pages to be had. Stop here...
 112                                 // TODO: Security issue - if the user has no right to view next title, it will still be shown
 113                                 $this->setContinueEnumParameter('continue', $this->getContinueStr($row, $lastSortKey));
 114                                 break;
 115                         }
 116
 117                         $lastSortKey = $row->cl_sortkey;        // detect duplicate sortkeys
 118
 119                         if (is_null($resultPageSet)) {
 120                                 $vals = array();
 121                                 if ($fld_ids)
 122                                         $vals['pageid'] = intval($row->page_id);
 123                                 if ($fld_title) {
 124                                         $title = Title :: makeTitle($row->page_namespace, $row->page_title);
 125                                         $vals['ns'] = intval($title->getNamespace());
 126                                         $vals['title'] = $title->getPrefixedText();
 127                                 }
 128                                 if ($fld_sortkey)
 129                                         $vals['sortkey'] = $row->cl_sortkey;
 130                                 if ($fld_timestamp)
 131                                         $vals['timestamp'] = wfTimestamp(TS_ISO_8601, $row->cl_timestamp);
 132                                 $data[] = $vals;
 133                         } else {
 134                                 $resultPageSet->processDbRow($row);
 135                         }
 136                 }
 137                 $db->freeResult($res);
 138
 139                 if (is_null($resultPageSet)) {
 140                         $this->getResult()->setIndexedTagName($data, 'cm');
 141                         $this->getResult()->addValue('query', $this->getModuleName(), $data);
 142                 }
 143         }
 144
 145         private function getContinueStr($row, $lastSortKey) {
 146                 $ret = $row->cl_sortkey . '|';
 147                 if ($row->cl_sortkey == $lastSortKey)   // duplicate sort key, add cl_from
 148                         $ret .= $row->cl_from;
 149                 return $ret;
 150         }
 151
 152         /**
 153          * Add DB WHERE clause to continue previous query based on 'continue' parameter
 154          */
 155         private function setContinuation($continue) {
 156                 if (is_null($continue))
 157                         return; // This is not a continuation request
 158
 159                 $continueList = explode('|', $continue);
 160                 $hasError = count($continueList) != 2;
 161                 $from = 0;
 162                 if (!$hasError && strlen($continueList[1]) > 0) {
 163                         $from = intval($continueList[1]);
 164                         $hasError = ($from == 0);
 165                 }
 166
 167                 if ($hasError)
 168                         $this->dieUsage("Invalid continue param. You should pass the original value returned by the previous query", "badcontinue");
 169
 170                 $encSortKey = $this->getDB()->addQuotes($continueList[0]);
 171                 $encFrom = $this->getDB()->addQuotes($from);
 172
 173                 if ($from != 0) {
 174                         // Duplicate sort key continue
 175                         $this->addWhere( "cl_sortkey>$encSortKey OR (cl_sortkey=$encSortKey AND cl_from>=$encFrom)" );
 176                 } else {
 177                         $this->addWhere( "cl_sortkey>=$encSortKey" );
 178                 }
 179         }
 180
 181         public function getAllowedParams() {
 182                 return array (
 183                         'title' => null,
 184                         'category' => null, // DEPRECATED, will be removed in early March
 185                         'prop' => array (
 186                                 ApiBase :: PARAM_DFLT => 'ids|title',
 187                                 ApiBase :: PARAM_ISMULTI => true,
 188                                 ApiBase :: PARAM_TYPE => array (
 189                                         'ids',
 190                                         'title',
 191                                         'sortkey',
 192                                         'timestamp',
 193                                 )
 194                         ),
 195                         'namespace' => array (
 196                                 ApiBase :: PARAM_ISMULTI => true,
 197                                 ApiBase :: PARAM_TYPE => 'namespace',
 198                         ),
 199                         'continue' => null,
 200                         'limit' => array (
 201                                 ApiBase :: PARAM_TYPE => 'limit',
 202                                 ApiBase :: PARAM_DFLT => 10,
 203                                 ApiBase :: PARAM_MIN => 1,
 204                                 ApiBase :: PARAM_MAX => ApiBase :: LIMIT_BIG1,
 205                                 ApiBase :: PARAM_MAX2 => ApiBase :: LIMIT_BIG2
 206                         ),
 207                         'sort' => array(
 208                                 ApiBase :: PARAM_DFLT => 'sortkey',
 209                                 ApiBase :: PARAM_TYPE => array(
 210                                         'sortkey',
 211                                         'timestamp'
 212                                 )
 213                         ),
 214                         'dir' => array(
 215                                 ApiBase :: PARAM_DFLT => 'asc',
 216                                 ApiBase :: PARAM_TYPE => array(
 217                                         'asc',
 218                                         'desc'
 219                                 )
 220                         )
 221                 );
 222         }
 223
 224         public function getParamDescription() {
 225                 return array (
 226                         'title' => 'Which category to enumerate (required). Must include Category: prefix',
 227                         'prop' => 'What pieces of information to include',
 228                         'namespace' => 'Only include pages in these namespaces',
 229                         'sort' => 'Property to sort by',
 230                         'dir' => 'In which direction to sort',
 231                         'continue' => 'For large categories, give the value retured from previous query',
 232                         'limit' => 'The maximum number of pages to return.',
 233                         'category' => 'DEPRECATED. Like title, but without the Category: prefix.',
 234                 );
 235         }
 236
 237         public function getDescription() {
 238                 return 'List all pages in a given category';
 239         }
 240
 241         protected function getExamples() {
 242                 return array (
 243                                 "Get first 10 pages in [[Category:Physics]]:",
 244                                 "  api.php?action=query&list=categorymembers&cmtitle=Category:Physics",
 245                                 "Get page info about first 10 pages in [[Category:Physics]]:",
 246                                 "  api.php?action=query&generator=categorymembers&gcmtitle=Category:Physics&prop=info",
 247                         );
 248         }
 249
 250         public function getVersion() {
 251                 return __CLASS__ . ': $Id$';
 252         }
 253 }
 254