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 = $this->extractRequestParams();
  53
  54                 if ( !isset($params['title']) || is_null($params['title']) )
  55                         $this->dieUsage("The cmtitle parameter is required", 'notitle');
  56                 $categoryTitle = Title::newFromText($params['title']);
  57
  58                 if ( is_null( $categoryTitle ) || $categoryTitle->getNamespace() != NS_CATEGORY )
  59                         $this->dieUsage("The category name you entered is not valid", 'invalidcategory');
  60
  61                 $prop = array_flip($params['prop']);
  62                 $fld_ids = isset($prop['ids']);
  63                 $fld_title = isset($prop['title']);
  64                 $fld_sortkey = isset($prop['sortkey']);
  65                 $fld_timestamp = isset($prop['timestamp']);
  66
  67                 if (is_null($resultPageSet)) {
  68                         $this->addFields(array('cl_from', 'cl_sortkey', 'page_namespace', 'page_title'));
  69                         $this->addFieldsIf('page_id', $fld_ids);
  70                 } else {
  71                         $this->addFields($resultPageSet->getPageTableFields()); // will include page_ id, ns, title
  72                         $this->addFields(array('cl_from', 'cl_sortkey'));
  73                 }
  74
  75                 $this->addFieldsIf('cl_timestamp', $fld_timestamp || $params['sort'] == 'timestamp');
  76                 $this->addTables(array('page','categorylinks'));        // must be in this order for 'USE INDEX'
  77                                                                         // Not needed after bug 10280 is applied to servers
  78                 if($params['sort'] == 'timestamp')
  79                 {
  80                         $this->addOption('USE INDEX', 'cl_timestamp');
  81                         $this->addOption('ORDER BY', 'cl_to, cl_timestamp' . ($params['dir'] == 'desc' ? ' DESC' : ''));
  82                 }
  83                 else
  84                 {
  85                         $this->addOption('USE INDEX', 'cl_sortkey');
  86                         $this->addOption('ORDER BY', 'cl_to, cl_sortkey' . ($params['dir'] == 'desc' ? ' DESC' : '') . ', cl_from');
  87                 }
  88
  89                 $this->addWhere('cl_from=page_id');
  90                 $this->setContinuation($params['continue']);
  91                 $this->addWhereFld('cl_to', $categoryTitle->getDBkey());
  92                 $this->addWhereFld('page_namespace', $params['namespace']);
  93                 $this->addWhereRange('cl_timestamp', ($params['dir'] == 'asc' ? 'newer' : 'older'), $params['start'], $params['end']);
  94
  95                 $limit = $params['limit'];
  96                 $this->addOption('LIMIT', $limit +1);
  97
  98                 $db = $this->getDB();
  99
 100                 $data = array ();
 101                 $count = 0;
 102                 $lastSortKey = null;
 103                 $res = $this->select(__METHOD__);
 104                 while ($row = $db->fetchObject($res)) {
 105                         if (++ $count > $limit) {
 106                                 // We've reached the one extra which shows that there are additional pages to be had. Stop here...
 107                                 // TODO: Security issue - if the user has no right to view next title, it will still be shown
 108                                 if ($params['sort'] == 'timestamp')
 109                                         $this->setContinueEnumParameter('start', $row->cl_timestamp);
 110                                 else
 111                                         $this->setContinueEnumParameter('continue', $this->getContinueStr($row, $lastSortKey));
 112                                 break;
 113                         }
 114
 115                         $lastSortKey = $row->cl_sortkey;        // detect duplicate sortkeys
 116
 117                         if (is_null($resultPageSet)) {
 118                                 $vals = array();
 119                                 if ($fld_ids)
 120                                         $vals['pageid'] = intval($row->page_id);
 121                                 if ($fld_title) {
 122                                         $title = Title :: makeTitle($row->page_namespace, $row->page_title);
 123                                         $vals['ns'] = intval($title->getNamespace());
 124                                         $vals['title'] = $title->getPrefixedText();
 125                                 }
 126                                 if ($fld_sortkey)
 127                                         $vals['sortkey'] = $row->cl_sortkey;
 128                                 if ($fld_timestamp)
 129                                         $vals['timestamp'] = wfTimestamp(TS_ISO_8601, $row->cl_timestamp);
 130                                 $data[] = $vals;
 131                         } else {
 132                                 $resultPageSet->processDbRow($row);
 133                         }
 134                 }
 135                 $db->freeResult($res);
 136
 137                 if (is_null($resultPageSet)) {
 138                         $this->getResult()->setIndexedTagName($data, 'cm');
 139                         $this->getResult()->addValue('query', $this->getModuleName(), $data);
 140                 }
 141         }
 142
 143         private function getContinueStr($row, $lastSortKey) {
 144                 $ret = $row->cl_sortkey . '|';
 145                 if ($row->cl_sortkey == $lastSortKey)   // duplicate sort key, add cl_from
 146                         $ret .= $row->cl_from;
 147                 return $ret;
 148         }
 149
 150         /**
 151          * Add DB WHERE clause to continue previous query based on 'continue' parameter
 152          */
 153         private function setContinuation($continue) {
 154                 if (is_null($continue))
 155                         return; // This is not a continuation request
 156
 157                 $continueList = explode('|', $continue);
 158                 $hasError = count($continueList) != 2;
 159                 $from = 0;
 160                 if (!$hasError && strlen($continueList[1]) > 0) {
 161                         $from = intval($continueList[1]);
 162                         $hasError = ($from == 0);
 163                 }
 164
 165                 if ($hasError)
 166                         $this->dieUsage("Invalid continue param. You should pass the original value returned by the previous query", "badcontinue");
 167
 168                 $encSortKey = $this->getDB()->addQuotes($continueList[0]);
 169                 $encFrom = $this->getDB()->addQuotes($from);
 170
 171                 if ($from != 0) {
 172                         // Duplicate sort key continue
 173                         $this->addWhere( "cl_sortkey>$encSortKey OR (cl_sortkey=$encSortKey AND cl_from>=$encFrom)" );
 174                 } else {
 175                         $this->addWhere( "cl_sortkey>=$encSortKey" );
 176                 }
 177         }
 178
 179         public function getAllowedParams() {
 180                 return array (
 181                         'title' => null,
 182                         'prop' => array (
 183                                 ApiBase :: PARAM_DFLT => 'ids|title',
 184                                 ApiBase :: PARAM_ISMULTI => true,
 185                                 ApiBase :: PARAM_TYPE => array (
 186                                         'ids',
 187                                         'title',
 188                                         'sortkey',
 189                                         'timestamp',
 190                                 )
 191                         ),
 192                         'namespace' => array (
 193                                 ApiBase :: PARAM_ISMULTI => true,
 194                                 ApiBase :: PARAM_TYPE => 'namespace',
 195                         ),
 196                         'continue' => null,
 197                         'limit' => array (
 198                                 ApiBase :: PARAM_TYPE => 'limit',
 199                                 ApiBase :: PARAM_DFLT => 10,
 200                                 ApiBase :: PARAM_MIN => 1,
 201                                 ApiBase :: PARAM_MAX => ApiBase :: LIMIT_BIG1,
 202                                 ApiBase :: PARAM_MAX2 => ApiBase :: LIMIT_BIG2
 203                         ),
 204                         'sort' => array(
 205                                 ApiBase :: PARAM_DFLT => 'sortkey',
 206                                 ApiBase :: PARAM_TYPE => array(
 207                                         'sortkey',
 208                                         'timestamp'
 209                                 )
 210                         ),
 211                         'dir' => array(
 212                                 ApiBase :: PARAM_DFLT => 'asc',
 213                                 ApiBase :: PARAM_TYPE => array(
 214                                         'asc',
 215                                         'desc'
 216                                 )
 217                         ),
 218                         'start' => array(
 219                                 ApiBase :: PARAM_TYPE => 'timestamp'
 220                         ),
 221                         'end' => array(
 222                                 ApiBase :: PARAM_TYPE => 'timestamp'
 223                         )
 224                 );
 225         }
 226
 227         public function getParamDescription() {
 228                 return array (
 229                         'title' => 'Which category to enumerate (required). Must include Category: prefix',
 230                         'prop' => 'What pieces of information to include',
 231                         'namespace' => 'Only include pages in these namespaces',
 232                         'sort' => 'Property to sort by',
 233                         'dir' => 'In which direction to sort',
 234                         'start' => 'Timestamp to start listing from',
 235                         'end' => 'Timestamp to end listing at',
 236                         'continue' => 'For large categories, give the value retured from previous query',
 237                         'limit' => 'The maximum number of pages to return.',
 238                 );
 239         }
 240
 241         public function getDescription() {
 242                 return 'List all pages in a given category';
 243         }
 244
 245         protected function getExamples() {
 246                 return array (
 247                                 "Get first 10 pages in [[Category:Physics]]:",
 248                                 "  api.php?action=query&list=categorymembers&cmtitle=Category:Physics",
 249                                 "Get page info about first 10 pages in [[Category:Physics]]:",
 250                                 "  api.php?action=query&generator=categorymembers&gcmtitle=Category:Physics&prop=info",
 251                         );
 252         }
 253
 254         public function getVersion() {
 255                 return __CLASS__ . ': $Id$';
 256         }
 257 }