4 * Created on Sep 7, 2006
6 * API for MediaWiki 1.8+
8 * Copyright (C) 2006 Yuri Astrakhan <Firstname><Lastname>@gmail.com
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.
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.
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
26 if ( !defined( 'MEDIAWIKI' ) ) {
27 // Eclipse helper - will be ignored in production
28 require_once ( 'ApiBase.php' );
32 * This is the main query class. It behaves similar to ApiMain: based on the
33 * parameters given, it will create a list of titles to work on (an ApiPageSet
34 * object), instantiate and execute various property/list/meta modules, and
35 * assemble all resulting data into a single ApiResult object.
37 * In generator mode, a generator will be executed first to populate a second
38 * ApiPageSet object, and that object will be used for all subsequent modules.
42 class ApiQuery extends ApiBase {
44 private $mPropModuleNames, $mListModuleNames, $mMetaModuleNames;
46 private $params, $redirect;
48 private $mQueryPropModules = array (
49 'info' => 'ApiQueryInfo',
50 'revisions' => 'ApiQueryRevisions',
51 'links' => 'ApiQueryLinks',
52 'langlinks' => 'ApiQueryLangLinks',
53 'images' => 'ApiQueryImages',
54 'imageinfo' => 'ApiQueryImageInfo',
55 'templates' => 'ApiQueryLinks',
56 'categories' => 'ApiQueryCategories',
57 'extlinks' => 'ApiQueryExternalLinks',
58 'categoryinfo' => 'ApiQueryCategoryInfo',
59 'duplicatefiles' => 'ApiQueryDuplicateFiles',
62 private $mQueryListModules = array (
63 'allimages' => 'ApiQueryAllimages',
64 'allpages' => 'ApiQueryAllpages',
65 'alllinks' => 'ApiQueryAllLinks',
66 'allcategories' => 'ApiQueryAllCategories',
67 'allusers' => 'ApiQueryAllUsers',
68 'backlinks' => 'ApiQueryBacklinks',
69 'blocks' => 'ApiQueryBlocks',
70 'categorymembers' => 'ApiQueryCategoryMembers',
71 'deletedrevs' => 'ApiQueryDeletedrevs',
72 'embeddedin' => 'ApiQueryBacklinks',
73 'imageusage' => 'ApiQueryBacklinks',
74 'logevents' => 'ApiQueryLogEvents',
75 'recentchanges' => 'ApiQueryRecentChanges',
76 'search' => 'ApiQuerySearch',
77 'tags' => 'ApiQueryTags',
78 'usercontribs' => 'ApiQueryContributions',
79 'watchlist' => 'ApiQueryWatchlist',
80 'watchlistraw' => 'ApiQueryWatchlistRaw',
81 'exturlusage' => 'ApiQueryExtLinksUsage',
82 'users' => 'ApiQueryUsers',
83 'random' => 'ApiQueryRandom',
84 'protectedtitles' => 'ApiQueryProtectedTitles',
87 private $mQueryMetaModules = array (
88 'siteinfo' => 'ApiQuerySiteinfo',
89 'userinfo' => 'ApiQueryUserInfo',
90 'allmessages' => 'ApiQueryAllmessages',
93 private $mSlaveDB = null;
94 private $mNamedDB = array();
96 public function __construct( $main, $action ) {
97 parent :: __construct( $main, $action );
99 // Allow custom modules to be added in LocalSettings.php
100 global $wgAPIPropModules, $wgAPIListModules, $wgAPIMetaModules;
101 self :: appendUserModules( $this->mQueryPropModules, $wgAPIPropModules );
102 self :: appendUserModules( $this->mQueryListModules, $wgAPIListModules );
103 self :: appendUserModules( $this->mQueryMetaModules, $wgAPIMetaModules );
105 $this->mPropModuleNames = array_keys( $this->mQueryPropModules );
106 $this->mListModuleNames = array_keys( $this->mQueryListModules );
107 $this->mMetaModuleNames = array_keys( $this->mQueryMetaModules );
109 // Allow the entire list of modules at first,
110 // but during module instantiation check if it can be used as a generator.
111 $this->mAllowedGenerators = array_merge( $this->mListModuleNames, $this->mPropModuleNames );
115 * Helper function to append any add-in modules to the list
116 * @param $modules array Module array
117 * @param $newModules array Module array to add to $modules
119 private static function appendUserModules( &$modules, $newModules ) {
120 if ( is_array( $newModules ) ) {
121 foreach ( $newModules as $moduleName => $moduleClass ) {
122 $modules[$moduleName] = $moduleClass;
128 * Gets a default slave database connection object
131 public function getDB() {
132 if ( !isset ( $this->mSlaveDB ) ) {
133 $this->profileDBIn();
134 $this->mSlaveDB = wfGetDB( DB_SLAVE, 'api' );
135 $this->profileDBOut();
137 return $this->mSlaveDB;
141 * Get the query database connection with the given name.
142 * If no such connection has been requested before, it will be created.
143 * Subsequent calls with the same $name will return the same connection
144 * as the first, regardless of the values of $db and $groups
145 * @param $name string Name to assign to the database connection
146 * @param $db int One of the DB_* constants
147 * @param $groups array Query groups
150 public function getNamedDB( $name, $db, $groups ) {
151 if ( !array_key_exists( $name, $this->mNamedDB ) ) {
152 $this->profileDBIn();
153 $this->mNamedDB[$name] = wfGetDB( $db, $groups );
154 $this->profileDBOut();
156 return $this->mNamedDB[$name];
160 * Gets the set of pages the user has requested (or generated)
163 public function getPageSet() {
164 return $this->mPageSet;
168 * Get the array mapping module names to class names
169 * @return array(modulename => classname)
171 function getModules() {
172 return array_merge( $this->mQueryPropModules, $this->mQueryListModules, $this->mQueryMetaModules );
175 public function getCustomPrinter() {
176 // If &exportnowrap is set, use the raw formatter
177 if ( $this->getParameter( 'export' ) &&
178 $this->getParameter( 'exportnowrap' ) )
179 return new ApiFormatRaw( $this->getMain(),
180 $this->getMain()->createPrinterByName( 'xml' ) );
186 * Query execution happens in the following steps:
187 * #1 Create a PageSet object with any pages requested by the user
188 * #2 If using a generator, execute it to get a new ApiPageSet object
189 * #3 Instantiate all requested modules.
190 * This way the PageSet object will know what shared data is required,
191 * and minimize DB calls.
192 * #4 Output all normalization and redirect resolution information
193 * #5 Execute all requested modules
195 public function execute() {
197 $this->params = $this->extractRequestParams();
198 $this->redirects = $this->params['redirects'];
201 $this->mPageSet = new ApiPageSet( $this, $this->redirects );
203 // Instantiate requested modules
205 $this->InstantiateModules( $modules, 'prop', $this->mQueryPropModules );
206 $this->InstantiateModules( $modules, 'list', $this->mQueryListModules );
207 $this->InstantiateModules( $modules, 'meta', $this->mQueryMetaModules );
209 $cacheMode = 'public';
211 // If given, execute generator to substitute user supplied data with generated data.
212 if ( isset ( $this->params['generator'] ) ) {
213 $generator = $this->newGenerator( $this->params['generator'] );
214 $params = $generator->extractRequestParams();
215 $cacheMode = $this->mergeCacheMode( $cacheMode,
216 $generator->getCacheMode( $params ) );
217 $this->executeGeneratorModule( $generator, $modules );
219 // Append custom fields and populate page/revision information
220 $this->addCustomFldsToPageSet( $modules, $this->mPageSet );
221 $this->mPageSet->execute();
224 // Record page information (title, namespace, if exists, etc)
225 $this->outputGeneralPageInfo();
227 // Execute all requested modules.
228 foreach ( $modules as $module ) {
229 $params = $module->extractRequestParams();
230 $cacheMode = $this->mergeCacheMode(
231 $cacheMode, $module->getCacheMode( $params ) );
232 $module->profileIn();
234 wfRunHooks( 'APIQueryAfterExecute', array( &$module ) );
235 $module->profileOut();
238 // Set the cache mode
239 $this->getMain()->setCacheMode( $cacheMode );
243 * Update a cache mode string, applying the cache mode of a new module to it.
244 * The cache mode may increase in the level of privacy, but public modules
245 * added to private data do not decrease the level of privacy.
247 protected function mergeCacheMode( $cacheMode, $modCacheMode ) {
248 if ( $modCacheMode === 'anon-public-user-private' ) {
249 if ( $cacheMode !== 'private' ) {
250 $cacheMode = 'anon-public-user-private';
252 } elseif ( $modCacheMode === 'public' ) {
253 // do nothing, if it's public already it will stay public
255 $cacheMode = 'private';
261 * Query modules may optimize data requests through the $this->getPageSet() object
262 * by adding extra fields from the page table.
263 * This function will gather all the extra request fields from the modules.
264 * @param $modules array of module objects
265 * @param $pageSet ApiPageSet
267 private function addCustomFldsToPageSet( $modules, $pageSet ) {
268 // Query all requested modules.
269 foreach ( $modules as $module ) {
270 $module->requestExtraData( $pageSet );
275 * Create instances of all modules requested by the client
276 * @param $modules array to append instatiated modules to
277 * @param $param string Parameter name to read modules from
278 * @param $moduleList array(modulename => classname)
280 private function InstantiateModules( &$modules, $param, $moduleList ) {
281 $list = @$this->params[$param];
282 if ( !is_null ( $list ) )
283 foreach ( $list as $moduleName )
284 $modules[] = new $moduleList[$moduleName] ( $this, $moduleName );
288 * Appends an element for each page in the current pageSet with the
289 * most general information (id, title), plus any title normalizations
290 * and missing or invalid title/pageids/revids.
292 private function outputGeneralPageInfo() {
294 $pageSet = $this->getPageSet();
295 $result = $this->getResult();
297 // We don't check for a full result set here because we can't be adding
298 // more than 380K. The maximum revision size is in the megabyte range,
299 // and the maximum result size must be even higher than that.
301 // Title normalizations
302 $normValues = array ();
303 foreach ( $pageSet->getNormalizedTitles() as $rawTitleStr => $titleStr ) {
304 $normValues[] = array (
305 'from' => $rawTitleStr,
310 if ( count( $normValues ) ) {
311 $result->setIndexedTagName( $normValues, 'n' );
312 $result->addValue( 'query', 'normalized', $normValues );
316 $intrwValues = array ();
317 foreach ( $pageSet->getInterwikiTitles() as $rawTitleStr => $interwikiStr ) {
318 $intrwValues[] = array (
319 'title' => $rawTitleStr,
320 'iw' => $interwikiStr
324 if ( count( $intrwValues ) ) {
325 $result->setIndexedTagName( $intrwValues, 'i' );
326 $result->addValue( 'query', 'interwiki', $intrwValues );
329 // Show redirect information
330 $redirValues = array ();
331 foreach ( $pageSet->getRedirectTitles() as $titleStrFrom => $titleStrTo ) {
332 $redirValues[] = array (
333 'from' => strval( $titleStrFrom ),
338 if ( count( $redirValues ) ) {
339 $result->setIndexedTagName( $redirValues, 'r' );
340 $result->addValue( 'query', 'redirects', $redirValues );
344 // Missing revision elements
346 $missingRevIDs = $pageSet->getMissingRevisionIDs();
347 if ( count( $missingRevIDs ) ) {
349 foreach ( $missingRevIDs as $revid ) {
350 $revids[$revid] = array (
354 $result->setIndexedTagName( $revids, 'rev' );
355 $result->addValue( 'query', 'badrevids', $revids );
363 // Report any missing titles
364 foreach ( $pageSet->getMissingTitles() as $fakeId => $title ) {
366 ApiQueryBase :: addTitleInfo( $vals, $title );
367 $vals['missing'] = '';
368 $pages[$fakeId] = $vals;
370 // Report any invalid titles
371 foreach ( $pageSet->getInvalidTitles() as $fakeId => $title )
372 $pages[$fakeId] = array( 'title' => $title, 'invalid' => '' );
373 // Report any missing page ids
374 foreach ( $pageSet->getMissingPageIDs() as $pageid ) {
375 $pages[$pageid] = array (
381 // Output general page information for found titles
382 foreach ( $pageSet->getGoodTitles() as $pageid => $title ) {
384 $vals['pageid'] = $pageid;
385 ApiQueryBase :: addTitleInfo( $vals, $title );
386 $pages[$pageid] = $vals;
389 if ( count( $pages ) ) {
391 if ( $this->params['indexpageids'] ) {
392 $pageIDs = array_keys( $pages );
393 // json treats all map keys as strings - converting to match
394 $pageIDs = array_map( 'strval', $pageIDs );
395 $result->setIndexedTagName( $pageIDs, 'id' );
396 $result->addValue( 'query', 'pageids', $pageIDs );
399 $result->setIndexedTagName( $pages, 'page' );
400 $result->addValue( 'query', 'pages', $pages );
402 if ( $this->params['export'] ) {
403 $exporter = new WikiExporter( $this->getDB() );
404 // WikiExporter writes to stdout, so catch its
407 $exporter->openStream();
408 foreach ( @$pageSet->getGoodTitles() as $title )
409 if ( $title->userCanRead() )
410 $exporter->pageByTitle( $title );
411 $exporter->closeStream();
412 $exportxml = ob_get_contents();
415 // Don't check the size of exported stuff
416 // It's not continuable, so it would cause more
417 // problems than it'd solve
418 $result->disableSizeCheck();
419 if ( $this->params['exportnowrap'] ) {
421 // Raw formatter will handle this
422 $result->addValue( null, 'text', $exportxml );
423 $result->addValue( null, 'mime', 'text/xml' );
426 ApiResult::setContent( $r, $exportxml );
427 $result->addValue( 'query', 'export', $r );
429 $result->enableSizeCheck();
434 * Create a generator object of the given type and return it
436 public function newGenerator( $generatorName ) {
438 // Find class that implements requested generator
439 if ( isset ( $this->mQueryListModules[$generatorName] ) ) {
440 $className = $this->mQueryListModules[$generatorName];
441 } elseif ( isset ( $this->mQueryPropModules[$generatorName] ) ) {
442 $className = $this->mQueryPropModules[$generatorName];
444 ApiBase :: dieDebug( __METHOD__, "Unknown generator=$generatorName" );
448 $resultPageSet = new ApiPageSet( $this, $this->redirects );
450 // Create and execute the generator
451 $generator = new $className ( $this, $generatorName );
452 if ( !$generator instanceof ApiQueryGeneratorBase )
453 $this->dieUsage( "Module $generatorName cannot be used as a generator", "badgenerator" );
454 $generator->setGeneratorMode();
459 * For generator mode, execute generator, and use its output as new
461 * @param $generatorName string Module name
462 * @param $modules array of module objects
464 protected function executeGeneratorModule( $generator, $modules ) {
466 $resultPageSet = new ApiPageSet( $this, $this->redirects, $this->convertTitles );
468 // Add any additional fields modules may need
469 $generator->requestExtraData( $this->mPageSet );
470 $this->addCustomFldsToPageSet( $modules, $resultPageSet );
472 // Populate page information with the original user input
473 $this->mPageSet->execute();
475 // populate resultPageSet with the generator output
476 $generator->profileIn();
477 $generator->executeGenerator( $resultPageSet );
478 wfRunHooks( 'APIQueryGeneratorAfterExecute', array( &$generator, &$resultPageSet ) );
479 $resultPageSet->finishPageSetGeneration();
480 $generator->profileOut();
482 // Swap the resulting pageset back in
483 $this->mPageSet = $resultPageSet;
486 public function getAllowedParams() {
489 ApiBase :: PARAM_ISMULTI => true,
490 ApiBase :: PARAM_TYPE => $this->mPropModuleNames
493 ApiBase :: PARAM_ISMULTI => true,
494 ApiBase :: PARAM_TYPE => $this->mListModuleNames
497 ApiBase :: PARAM_ISMULTI => true,
498 ApiBase :: PARAM_TYPE => $this->mMetaModuleNames
500 'generator' => array (
501 ApiBase :: PARAM_TYPE => $this->mAllowedGenerators
503 'redirects' => false,
504 'indexpageids' => false,
506 'exportnowrap' => false,
511 * Override the parent to generate help messages for all available query modules.
514 public function makeHelpMsg() {
518 // Make sure the internal object is empty
519 // (just in case a sub-module decides to optimize during instantiation)
520 $this->mPageSet = null;
521 $this->mAllowedGenerators = array(); // Will be repopulated
523 $astriks = str_repeat( '--- ', 8 );
524 $astriks2 = str_repeat( '*** ', 10 );
525 $msg .= "\n$astriks Query: Prop $astriks\n\n";
526 $msg .= $this->makeHelpMsgHelper( $this->mQueryPropModules, 'prop' );
527 $msg .= "\n$astriks Query: List $astriks\n\n";
528 $msg .= $this->makeHelpMsgHelper( $this->mQueryListModules, 'list' );
529 $msg .= "\n$astriks Query: Meta $astriks\n\n";
530 $msg .= $this->makeHelpMsgHelper( $this->mQueryMetaModules, 'meta' );
531 $msg .= "\n\n$astriks2 Modules: continuation $astriks2\n\n";
533 // Perform the base call last because the $this->mAllowedGenerators
534 // will be updated inside makeHelpMsgHelper()
535 // Use parent to make default message for the query module
536 $msg = parent :: makeHelpMsg() . $msg;
542 * For all modules in $moduleList, generate help messages and join them together
543 * @param $moduleList array(modulename => classname)
544 * @param $paramName string Parameter name
547 private function makeHelpMsgHelper( $moduleList, $paramName ) {
549 $moduleDescriptions = array ();
551 foreach ( $moduleList as $moduleName => $moduleClass ) {
552 $module = new $moduleClass ( $this, $moduleName, null );
554 $msg = ApiMain::makeHelpMsgHeader( $module, $paramName );
555 $msg2 = $module->makeHelpMsg();
556 if ( $msg2 !== false )
558 if ( $module instanceof ApiQueryGeneratorBase ) {
559 $this->mAllowedGenerators[] = $moduleName;
560 $msg .= "Generator:\n This module may be used as a generator\n";
562 $moduleDescriptions[] = $msg;
565 return implode( "\n", $moduleDescriptions );
569 * Override to add extra parameters from PageSet
572 public function makeHelpMsgParameters() {
573 $psModule = new ApiPageSet( $this );
574 return $psModule->makeHelpMsgParameters() . parent :: makeHelpMsgParameters();
577 public function shouldCheckMaxlag() {
581 public function getParamDescription() {
583 'prop' => 'Which properties to get for the titles/revisions/pageids',
584 'list' => 'Which lists to get',
585 'meta' => 'Which meta data to get about the site',
586 'generator' => array( 'Use the output of a list as the input for other prop/list/meta items',
587 'NOTE: generator parameter names must be prefixed with a \'g\', see examples.' ),
588 'redirects' => 'Automatically resolve redirects',
589 'indexpageids' => 'Include an additional pageids section listing all returned page IDs.',
590 'export' => 'Export the current revisions of all given or generated pages',
591 'exportnowrap' => 'Return the export XML without wrapping it in an XML result (same format as Special:Export). Can only be used with export',
595 public function getDescription() {
597 'Query API module allows applications to get needed pieces of data from the MediaWiki databases,',
598 'and is loosely based on the old query.php interface.',
599 'All data modifications will first have to use query to acquire a token to prevent abuse from malicious sites.'
603 public function getPossibleErrors() {
604 return array_merge( parent::getPossibleErrors(), array(
605 array( 'code' => 'badgenerator', 'info' => 'Module $generatorName cannot be used as a generator' ),
609 protected function getExamples() {
611 'api.php?action=query&prop=revisions&meta=siteinfo&titles=Main%20Page&rvprop=user|comment',
612 'api.php?action=query&generator=allpages&gapprefix=API/&prop=revisions',
616 public function getVersion() {
617 $psModule = new ApiPageSet( $this );
619 $vers[] = __CLASS__ . ': $Id: ApiQuery.php 69932 2010-07-26 08:03:21Z tstarling $';
620 $vers[] = $psModule->getVersion();