includes/api/ApiQuery.php

   1 <?php
   2
   3
   4 /*
   5  * Created on Sep 7, 2006
   6  *
   7  * API for MediaWiki 1.8+
   8  *
   9  * Copyright (C) 2006 Yuri Astrakhan <FirstnameLastname@gmail.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License along
  22  * with this program; if not, write to the Free Software Foundation, Inc.,
  23  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  24  * http://www.gnu.org/copyleft/gpl.html
  25  */
  26
  27 if (!defined('MEDIAWIKI')) {
  28         // Eclipse helper - will be ignored in production
  29         require_once ('ApiBase.php');
  30 }
  31
  32 class ApiQuery extends ApiBase {
  33
  34         private $mPropModuleNames, $mListModuleNames, $mMetaModuleNames;
  35         private $mPageSet;
  36
  37         private $mQueryPropModules = array (
  38                 'info' => 'ApiQueryInfo',
  39                 'revisions' => 'ApiQueryRevisions'
  40         );
  41         //      'categories' => 'ApiQueryCategories',
  42         //      'imageinfo' => 'ApiQueryImageinfo',
  43         //      'langlinks' => 'ApiQueryLanglinks',
  44         //      'links' => 'ApiQueryLinks',
  45         //      'templates' => 'ApiQueryTemplates',
  46
  47         private $mQueryListModules = array (
  48                 'allpages' => 'ApiQueryAllpages'
  49         );
  50         //      'backlinks' => 'ApiQueryBacklinks',
  51         //      'categorymembers' => 'ApiQueryCategorymembers',
  52         //      'embeddedin' => 'ApiQueryEmbeddedin',
  53         //      'imagelinks' => 'ApiQueryImagelinks',
  54         //      'logevents' => 'ApiQueryLogevents',
  55         //      'recentchanges' => 'ApiQueryRecentchanges',
  56         //      'usercontribs' => 'ApiQueryUsercontribs',
  57         //      'users' => 'ApiQueryUsers',
  58         //      'watchlist' => 'ApiQueryWatchlist',
  59
  60         private $mQueryMetaModules = array (
  61                 'siteinfo' => 'ApiQuerySiteinfo'
  62         );
  63         //      'userinfo' => 'ApiQueryUserinfo',
  64
  65         private $mSlaveDB = null;
  66
  67         public function __construct($main, $action) {
  68                 parent :: __construct($main, $action);
  69                 $this->mPropModuleNames = array_keys($this->mQueryPropModules);
  70                 $this->mListModuleNames = array_keys($this->mQueryListModules);
  71                 $this->mMetaModuleNames = array_keys($this->mQueryMetaModules);
  72
  73                 // Allow the entire list of modules at first,
  74                 // but during module instantiation check if it can be used as a generator.
  75                 $this->mAllowedGenerators = array_merge($this->mListModuleNames, $this->mPropModuleNames);
  76         }
  77
  78         public function getDB() {
  79                 if (!isset ($this->mSlaveDB))
  80                         $this->mSlaveDB = & wfGetDB(DB_SLAVE);
  81                 return $this->mSlaveDB;
  82         }
  83
  84         public function getPageSet() {
  85                 return $this->mPageSet;
  86         }
  87
  88         /**
  89          * Query execution happens in the following steps:
  90          * #1 Create a PageSet object with any pages requested by the user
  91          * #2 If using generator, execute it to get a new PageSet object
  92          * #3 Instantiate all requested modules.
  93          *    This way the PageSet object will know what shared data is required,
  94          *    and minimize DB calls.
  95          * #4 Output all normalization and redirect resolution information
  96          * #5 Execute all requested modules
  97          */
  98         public function execute() {
  99                 $prop = $list = $meta = $generator = $redirects = null;
 100                 extract($this->extractRequestParams());
 101
 102                 //
 103                 // Create PageSet
 104                 //
 105                 $this->mPageSet = new ApiPageSet($this, $redirects);
 106
 107                 // Instantiate required modules
 108                 $modules = array ();
 109                 if (isset ($prop))
 110                         foreach ($prop as $moduleName)
 111                                 $modules[] = new $this->mQueryPropModules[$moduleName] ($this, $moduleName);
 112                 if (isset ($list))
 113                         foreach ($list as $moduleName)
 114                                 $modules[] = new $this->mQueryListModules[$moduleName] ($this, $moduleName);
 115                 if (isset ($meta))
 116                         foreach ($meta as $moduleName)
 117                                 $modules[] = new $this->mQueryMetaModules[$moduleName] ($this, $moduleName);
 118
 119                 // Modules may optimize data requests through the $this->getPageSet() object
 120                 // Execute all requested modules.
 121                 foreach ($modules as $module) {
 122                         $module->requestExtraData();
 123                 }
 124
 125                 //
 126                 // If given, execute generator to substitute user supplied data with generated data.
 127                 //
 128                 if (isset ($generator))
 129                         $this->executeGeneratorModule($generator, $redirects);
 130
 131                 //
 132                 // Populate page information for the given pageSet
 133                 //
 134                 $this->mPageSet->execute();
 135
 136                 //
 137                 // Record page information (title, namespace, if exists, etc)
 138                 //
 139                 $this->outputGeneralPageInfo();
 140
 141                 //
 142                 // Execute all requested modules.
 143                 //
 144                 foreach ($modules as $module) {
 145                         $module->profileIn();
 146                         $module->execute();
 147                         $module->profileOut();
 148                 }
 149         }
 150
 151         private function outputGeneralPageInfo() {
 152
 153                 $pageSet = $this->getPageSet();
 154
 155                 // Title normalizations
 156                 $normValues = array ();
 157                 foreach ($pageSet->getNormalizedTitles() as $rawTitleStr => $titleStr) {
 158                         $normValues[] = array (
 159                                 'from' => $rawTitleStr,
 160                                 'to' => $titleStr
 161                         );
 162                 }
 163
 164                 if (!empty ($normValues)) {
 165                         ApiResult :: setIndexedTagName($normValues, 'n');
 166                         $this->getResult()->addValue('query', 'normalized', $normValues);
 167                 }
 168
 169                 // Show redirect information
 170                 $redirValues = array ();
 171                 foreach ($pageSet->getRedirectTitles() as $titleStrFrom => $titleStrTo) {
 172                         $redirValues[] = array (
 173                                 'from' => $titleStrFrom,
 174                                 'to' => $titleStrTo
 175                         );
 176                 }
 177
 178                 if (!empty ($redirValues)) {
 179                         ApiResult :: setIndexedTagName($redirValues, 'r');
 180                         $this->getResult()->addValue('query', 'redirects', $redirValues);
 181                 }
 182
 183                 //
 184                 // Page elements
 185                 //
 186                 $pages = array ();
 187
 188                 // Report any missing titles
 189                 $fakepageid = -1;
 190                 foreach ($pageSet->getMissingTitles() as $title) {
 191                         $pages[$fakepageid--] = array (
 192                         'ns' => $title->getNamespace(), 'title' => $title->getPrefixedText(), 'missing' => '');
 193                 }
 194
 195                 // Report any missing page ids
 196                 foreach ($pageSet->getMissingPageIDs() as $pageid) {
 197                         $pages[$pageid] = array (
 198                                 'id' => $pageid,
 199                                 'missing' => ''
 200                         );
 201                 }
 202
 203                 // Output general page information for found titles
 204                 foreach ($pageSet->getGoodTitles() as $pageid => $title) {
 205                         $pages[$pageid] = array (
 206                         'ns' => $title->getNamespace(), 'title' => $title->getPrefixedText(), 'id' => $pageid);
 207                 }
 208
 209                 if (!empty ($pages)) {
 210                         ApiResult :: setIndexedTagName($pages, 'page');
 211                         $this->getResult()->addValue('query', 'pages', $pages);
 212                 }
 213         }
 214
 215         protected function executeGeneratorModule($generatorName, $redirects) {
 216
 217                 // Find class that implements requested generator
 218                 if (isset ($this->mQueryListModules[$generatorName])) {
 219                         $className = $this->mQueryListModules[$generatorName];
 220                 }
 221                 elseif (isset ($this->mQueryPropModules[$generatorName])) {
 222                         $className = $this->mQueryPropModules[$generatorName];
 223                 } else {
 224                         ApiBase :: dieDebug(__METHOD__, "Unknown generator=$generatorName");
 225                 }
 226
 227                 // Use current pageset as the result, and create a new one just for the generator
 228                 $resultPageSet = $this->mPageSet;
 229                 $this->mPageSet = new ApiPageSet($this, $redirects);
 230
 231                 // Create and execute the generator
 232                 $generator = new $className ($this, $generatorName);
 233                 if (!$generator instanceof ApiQueryGeneratorBase)
 234                         $this->dieUsage("Module $generatorName cannot be used as a generator", "badgenerator");
 235
 236                 $generator->setGeneratorMode();
 237                 $generator->requestExtraData();
 238
 239                 // execute current pageSet to get the data for the generator module
 240                 $this->mPageSet->execute();
 241
 242                 // populate resultPageSet with the generator output
 243                 $generator->profileIn();
 244                 $generator->executeGenerator($resultPageSet);
 245                 $resultPageSet->finishPageSetGeneration();
 246                 $generator->profileOut();
 247
 248                 // Swap the resulting pageset back in
 249                 $this->mPageSet = $resultPageSet;
 250         }
 251
 252         protected function getAllowedParams() {
 253                 return array (
 254                         'prop' => array (
 255                                 ApiBase :: PARAM_ISMULTI => true,
 256                                 ApiBase :: PARAM_TYPE => $this->mPropModuleNames
 257                         ),
 258                         'list' => array (
 259                                 ApiBase :: PARAM_ISMULTI => true,
 260                                 ApiBase :: PARAM_TYPE => $this->mListModuleNames
 261                         ),
 262                         'meta' => array (
 263                                 ApiBase :: PARAM_ISMULTI => true,
 264                                 ApiBase :: PARAM_TYPE => $this->mMetaModuleNames
 265                         ),
 266                         'generator' => array (
 267                                 ApiBase :: PARAM_TYPE => $this->mAllowedGenerators
 268                         ),
 269                         'redirects' => false
 270                 );
 271         }
 272
 273         /**
 274          * Override the parent to generate help messages for all available query modules.
 275          */
 276         public function makeHelpMsg() {
 277
 278                 // Use parent to make default message for the query module
 279                 $msg = parent :: makeHelpMsg();
 280
 281                 // Make sure the internal object is empty
 282                 // (just in case a sub-module decides to optimize during instantiation)
 283                 $this->mPageSet = null;
 284
 285                 $astriks = str_repeat('--- ', 8);
 286                 $msg .= "\n$astriks Query: Prop  $astriks\n\n";
 287                 $msg .= $this->makeHelpMsgHelper($this->mQueryPropModules, 'prop');
 288                 $msg .= "\n$astriks Query: List  $astriks\n\n";
 289                 $msg .= $this->makeHelpMsgHelper($this->mQueryListModules, 'list');
 290                 $msg .= "\n$astriks Query: Meta  $astriks\n\n";
 291                 $msg .= $this->makeHelpMsgHelper($this->mQueryMetaModules, 'meta');
 292
 293                 return $msg;
 294         }
 295
 296         private function makeHelpMsgHelper($moduleList, $paramName) {
 297
 298                 $moduleDscriptions = array ();
 299
 300                 foreach ($moduleList as $moduleName => $moduleClass) {
 301                         $msg = "* $paramName=$moduleName *";
 302                         $module = new $moduleClass ($this, $moduleName, null);
 303                         $msg2 = $module->makeHelpMsg();
 304                         if ($msg2 !== false)
 305                                 $msg .= $msg2;
 306                         if ($module instanceof ApiQueryGeneratorBase)
 307                                 $msg .= "Generator:\n  This module may be used as a generator\n";
 308                         $moduleDscriptions[] = $msg;
 309                 }
 310
 311                 return implode("\n", $moduleDscriptions);
 312         }
 313
 314         /**
 315          * Override to add extra parameters from PageSet
 316          */
 317         public function makeHelpMsgParameters() {
 318                 $psModule = new ApiPageSet($this);
 319                 return $psModule->makeHelpMsgParameters() . parent :: makeHelpMsgParameters();
 320         }
 321
 322         protected function getParamDescription() {
 323                 return array (
 324                         'prop' => 'Which properties to get for the titles/revisions/pageids',
 325                         'list' => 'Which lists to get',
 326                         'meta' => 'Which meta data to get about the site',
 327                         'generator' => 'Use the output of a list as the input for other prop/list/meta items',
 328                         'redirects' => 'Automatically resolve redirects'
 329                 );
 330         }
 331
 332         protected function getDescription() {
 333                 return array (
 334                         'Query API module allows applications to get needed pieces of data from the MediaWiki databases,',
 335                         'and is loosely based on the Query API interface currently available on all MediaWiki servers.',
 336                         'All data modifications will first have to use query to acquire a token to prevent abuse from malicious sites.'
 337                 );
 338         }
 339
 340         protected function getExamples() {
 341                 return array (
 342                         'api.php?action=query&prop=revisions&meta=siteinfo&titles=Main%20Page&rvprop=user|comment'
 343                 );
 344         }
 345
 346         public function getVersion() {
 347                 $psModule = new ApiPageSet($this);
 348                 $vers = array ();
 349                 $vers[] = __CLASS__ . ': $Id$';
 350                 $vers[] = $psModule->getVersion();
 351                 return $vers;
 352         }
 353 }
 354 ?>