Merge "XMP: Throw generic exceptions instead of MWException"
[lhc/web/wiklou.git] / includes / api / ApiQuery.php
1 <?php
2 /**
3 *
4 *
5 * Created on Sep 7, 2006
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 * This is the main query class. It behaves similar to ApiMain: based on the
29 * parameters given, it will create a list of titles to work on (an ApiPageSet
30 * object), instantiate and execute various property/list/meta modules, and
31 * assemble all resulting data into a single ApiResult object.
32 *
33 * In generator mode, a generator will be executed first to populate a second
34 * ApiPageSet object, and that object will be used for all subsequent modules.
35 *
36 * @ingroup API
37 */
38 class ApiQuery extends ApiBase {
39
40 /**
41 * List of Api Query prop modules
42 * @var array
43 */
44 private static $QueryPropModules = array(
45 'categories' => 'ApiQueryCategories',
46 'categoryinfo' => 'ApiQueryCategoryInfo',
47 'contributors' => 'ApiQueryContributors',
48 'deletedrevisions' => 'ApiQueryDeletedRevisions',
49 'duplicatefiles' => 'ApiQueryDuplicateFiles',
50 'extlinks' => 'ApiQueryExternalLinks',
51 'fileusage' => 'ApiQueryBacklinksprop',
52 'images' => 'ApiQueryImages',
53 'imageinfo' => 'ApiQueryImageInfo',
54 'info' => 'ApiQueryInfo',
55 'links' => 'ApiQueryLinks',
56 'linkshere' => 'ApiQueryBacklinksprop',
57 'iwlinks' => 'ApiQueryIWLinks',
58 'langlinks' => 'ApiQueryLangLinks',
59 'pageprops' => 'ApiQueryPageProps',
60 'redirects' => 'ApiQueryBacklinksprop',
61 'revisions' => 'ApiQueryRevisions',
62 'stashimageinfo' => 'ApiQueryStashImageInfo',
63 'templates' => 'ApiQueryLinks',
64 'transcludedin' => 'ApiQueryBacklinksprop',
65 );
66
67 /**
68 * List of Api Query list modules
69 * @var array
70 */
71 private static $QueryListModules = array(
72 'allcategories' => 'ApiQueryAllCategories',
73 'alldeletedrevisions' => 'ApiQueryAllDeletedRevisions',
74 'allfileusages' => 'ApiQueryAllLinks',
75 'allimages' => 'ApiQueryAllImages',
76 'alllinks' => 'ApiQueryAllLinks',
77 'allpages' => 'ApiQueryAllPages',
78 'allredirects' => 'ApiQueryAllLinks',
79 'alltransclusions' => 'ApiQueryAllLinks',
80 'allusers' => 'ApiQueryAllUsers',
81 'backlinks' => 'ApiQueryBacklinks',
82 'blocks' => 'ApiQueryBlocks',
83 'categorymembers' => 'ApiQueryCategoryMembers',
84 'deletedrevs' => 'ApiQueryDeletedrevs',
85 'embeddedin' => 'ApiQueryBacklinks',
86 'exturlusage' => 'ApiQueryExtLinksUsage',
87 'filearchive' => 'ApiQueryFilearchive',
88 'imageusage' => 'ApiQueryBacklinks',
89 'iwbacklinks' => 'ApiQueryIWBacklinks',
90 'langbacklinks' => 'ApiQueryLangBacklinks',
91 'logevents' => 'ApiQueryLogEvents',
92 'pageswithprop' => 'ApiQueryPagesWithProp',
93 'pagepropnames' => 'ApiQueryPagePropNames',
94 'prefixsearch' => 'ApiQueryPrefixSearch',
95 'protectedtitles' => 'ApiQueryProtectedTitles',
96 'querypage' => 'ApiQueryQueryPage',
97 'random' => 'ApiQueryRandom',
98 'recentchanges' => 'ApiQueryRecentChanges',
99 'search' => 'ApiQuerySearch',
100 'tags' => 'ApiQueryTags',
101 'usercontribs' => 'ApiQueryContributions',
102 'users' => 'ApiQueryUsers',
103 'watchlist' => 'ApiQueryWatchlist',
104 'watchlistraw' => 'ApiQueryWatchlistRaw',
105 );
106
107 /**
108 * List of Api Query meta modules
109 * @var array
110 */
111 private static $QueryMetaModules = array(
112 'allmessages' => 'ApiQueryAllMessages',
113 'siteinfo' => 'ApiQuerySiteinfo',
114 'userinfo' => 'ApiQueryUserInfo',
115 'filerepoinfo' => 'ApiQueryFileRepoInfo',
116 'tokens' => 'ApiQueryTokens',
117 );
118
119 /**
120 * @var ApiPageSet
121 */
122 private $mPageSet;
123
124 private $mParams;
125 private $mNamedDB = array();
126 private $mModuleMgr;
127
128 /**
129 * @param ApiMain $main
130 * @param string $action
131 */
132 public function __construct( ApiMain $main, $action ) {
133 parent::__construct( $main, $action );
134
135 $this->mModuleMgr = new ApiModuleManager( $this );
136
137 // Allow custom modules to be added in LocalSettings.php
138 $config = $this->getConfig();
139 $this->mModuleMgr->addModules( self::$QueryPropModules, 'prop' );
140 $this->mModuleMgr->addModules( $config->get( 'APIPropModules' ), 'prop' );
141 $this->mModuleMgr->addModules( self::$QueryListModules, 'list' );
142 $this->mModuleMgr->addModules( $config->get( 'APIListModules' ), 'list' );
143 $this->mModuleMgr->addModules( self::$QueryMetaModules, 'meta' );
144 $this->mModuleMgr->addModules( $config->get( 'APIMetaModules' ), 'meta' );
145
146 Hooks::run( 'ApiQuery::moduleManager', array( $this->mModuleMgr ) );
147
148 // Create PageSet that will process titles/pageids/revids/generator
149 $this->mPageSet = new ApiPageSet( $this );
150 }
151
152 /**
153 * Overrides to return this instance's module manager.
154 * @return ApiModuleManager
155 */
156 public function getModuleManager() {
157 return $this->mModuleMgr;
158 }
159
160 /**
161 * Get the query database connection with the given name.
162 * If no such connection has been requested before, it will be created.
163 * Subsequent calls with the same $name will return the same connection
164 * as the first, regardless of the values of $db and $groups
165 * @param string $name Name to assign to the database connection
166 * @param int $db One of the DB_* constants
167 * @param array $groups Query groups
168 * @return DatabaseBase
169 */
170 public function getNamedDB( $name, $db, $groups ) {
171 if ( !array_key_exists( $name, $this->mNamedDB ) ) {
172 $this->mNamedDB[$name] = wfGetDB( $db, $groups );
173 }
174
175 return $this->mNamedDB[$name];
176 }
177
178 /**
179 * Gets the set of pages the user has requested (or generated)
180 * @return ApiPageSet
181 */
182 public function getPageSet() {
183 return $this->mPageSet;
184 }
185
186 /**
187 * Get the array mapping module names to class names
188 * @deprecated since 1.21, use getModuleManager()'s methods instead
189 * @return array Array(modulename => classname)
190 */
191 public function getModules() {
192 wfDeprecated( __METHOD__, '1.21' );
193
194 return $this->getModuleManager()->getNamesWithClasses();
195 }
196
197 /**
198 * Get the generators array mapping module names to class names
199 * @deprecated since 1.21, list of generators is maintained by ApiPageSet
200 * @return array Array(modulename => classname)
201 */
202 public function getGenerators() {
203 wfDeprecated( __METHOD__, '1.21' );
204 $gens = array();
205 foreach ( $this->mModuleMgr->getNamesWithClasses() as $name => $class ) {
206 if ( is_subclass_of( $class, 'ApiQueryGeneratorBase' ) ) {
207 $gens[$name] = $class;
208 }
209 }
210
211 return $gens;
212 }
213
214 /**
215 * Get whether the specified module is a prop, list or a meta query module
216 * @deprecated since 1.21, use getModuleManager()->getModuleGroup()
217 * @param string $moduleName Name of the module to find type for
218 * @return string|null
219 */
220 function getModuleType( $moduleName ) {
221 return $this->getModuleManager()->getModuleGroup( $moduleName );
222 }
223
224 /**
225 * @return ApiFormatRaw|null
226 */
227 public function getCustomPrinter() {
228 // If &exportnowrap is set, use the raw formatter
229 if ( $this->getParameter( 'export' ) &&
230 $this->getParameter( 'exportnowrap' )
231 ) {
232 return new ApiFormatRaw( $this->getMain(),
233 $this->getMain()->createPrinterByName( 'xml' ) );
234 } else {
235 return null;
236 }
237 }
238
239 /**
240 * Query execution happens in the following steps:
241 * #1 Create a PageSet object with any pages requested by the user
242 * #2 If using a generator, execute it to get a new ApiPageSet object
243 * #3 Instantiate all requested modules.
244 * This way the PageSet object will know what shared data is required,
245 * and minimize DB calls.
246 * #4 Output all normalization and redirect resolution information
247 * #5 Execute all requested modules
248 */
249 public function execute() {
250 $this->mParams = $this->extractRequestParams();
251
252 // Instantiate requested modules
253 $allModules = array();
254 $this->instantiateModules( $allModules, 'prop' );
255 $propModules = array_keys( $allModules );
256 $this->instantiateModules( $allModules, 'list' );
257 $this->instantiateModules( $allModules, 'meta' );
258
259 // Filter modules based on continue parameter
260 $continuationManager = new ApiContinuationManager( $this, $allModules, $propModules );
261 $this->setContinuationManager( $continuationManager );
262 $modules = $continuationManager->getRunModules();
263
264 if ( !$continuationManager->isGeneratorDone() ) {
265 // Query modules may optimize data requests through the $this->getPageSet()
266 // object by adding extra fields from the page table.
267 foreach ( $modules as $module ) {
268 $module->requestExtraData( $this->mPageSet );
269 }
270 // Populate page/revision information
271 $this->mPageSet->execute();
272 // Record page information (title, namespace, if exists, etc)
273 $this->outputGeneralPageInfo();
274 } else {
275 $this->mPageSet->executeDryRun();
276 }
277
278 $cacheMode = $this->mPageSet->getCacheMode();
279
280 // Execute all unfinished modules
281 /** @var $module ApiQueryBase */
282 foreach ( $modules as $module ) {
283 $params = $module->extractRequestParams();
284 $cacheMode = $this->mergeCacheMode(
285 $cacheMode, $module->getCacheMode( $params ) );
286 $module->execute();
287 Hooks::run( 'APIQueryAfterExecute', array( &$module ) );
288 }
289
290 // Set the cache mode
291 $this->getMain()->setCacheMode( $cacheMode );
292
293 // Write the continuation data into the result
294 $this->setContinuationManager( null );
295 if ( $this->mParams['continue'] === null ) {
296 $data = $continuationManager->getRawContinuation();
297 if ( $data ) {
298 $this->getResult()->addValue( null, 'query-continue', $data,
299 ApiResult::ADD_ON_TOP | ApiResult::NO_SIZE_CHECK );
300 }
301 } else {
302 $continuationManager->setContinuationIntoResult( $this->getResult() );
303 }
304
305 if ( $this->mParams['continue'] === null && !$this->mParams['rawcontinue'] &&
306 $this->getResult()->getResultData( 'query-continue' ) !== null
307 ) {
308 $this->logFeatureUsage( 'action=query&!rawcontinue&!continue' );
309 $this->setWarning(
310 'Formatting of continuation data will be changing soon. ' .
311 'To continue using the current formatting, use the \'rawcontinue\' parameter. ' .
312 'To begin using the new format, pass an empty string for \'continue\' ' .
313 'in the initial query.'
314 );
315 }
316 }
317
318 /**
319 * Update a cache mode string, applying the cache mode of a new module to it.
320 * The cache mode may increase in the level of privacy, but public modules
321 * added to private data do not decrease the level of privacy.
322 *
323 * @param string $cacheMode
324 * @param string $modCacheMode
325 * @return string
326 */
327 protected function mergeCacheMode( $cacheMode, $modCacheMode ) {
328 if ( $modCacheMode === 'anon-public-user-private' ) {
329 if ( $cacheMode !== 'private' ) {
330 $cacheMode = 'anon-public-user-private';
331 }
332 } elseif ( $modCacheMode === 'public' ) {
333 // do nothing, if it's public already it will stay public
334 } else { // private
335 $cacheMode = 'private';
336 }
337
338 return $cacheMode;
339 }
340
341 /**
342 * Create instances of all modules requested by the client
343 * @param array $modules To append instantiated modules to
344 * @param string $param Parameter name to read modules from
345 */
346 private function instantiateModules( &$modules, $param ) {
347 $wasPosted = $this->getRequest()->wasPosted();
348 if ( isset( $this->mParams[$param] ) ) {
349 foreach ( $this->mParams[$param] as $moduleName ) {
350 $instance = $this->mModuleMgr->getModule( $moduleName, $param );
351 if ( $instance === null ) {
352 ApiBase::dieDebug( __METHOD__, 'Error instantiating module' );
353 }
354 if ( !$wasPosted && $instance->mustBePosted() ) {
355 $this->dieUsageMsgOrDebug( array( 'mustbeposted', $moduleName ) );
356 }
357 // Ignore duplicates. TODO 2.0: die()?
358 if ( !array_key_exists( $moduleName, $modules ) ) {
359 $modules[$moduleName] = $instance;
360 }
361 }
362 }
363 }
364
365 /**
366 * Appends an element for each page in the current pageSet with the
367 * most general information (id, title), plus any title normalizations
368 * and missing or invalid title/pageids/revids.
369 */
370 private function outputGeneralPageInfo() {
371 $pageSet = $this->getPageSet();
372 $result = $this->getResult();
373
374 // We can't really handle max-result-size failure here, but we need to
375 // check anyway in case someone set the limit stupidly low.
376 $fit = true;
377
378 $values = $pageSet->getNormalizedTitlesAsResult( $result );
379 if ( $values ) {
380 $fit = $fit && $result->addValue( 'query', 'normalized', $values );
381 }
382 $values = $pageSet->getConvertedTitlesAsResult( $result );
383 if ( $values ) {
384 $fit = $fit && $result->addValue( 'query', 'converted', $values );
385 }
386 $values = $pageSet->getInterwikiTitlesAsResult( $result, $this->mParams['iwurl'] );
387 if ( $values ) {
388 $fit = $fit && $result->addValue( 'query', 'interwiki', $values );
389 }
390 $values = $pageSet->getRedirectTitlesAsResult( $result );
391 if ( $values ) {
392 $fit = $fit && $result->addValue( 'query', 'redirects', $values );
393 }
394 $values = $pageSet->getMissingRevisionIDsAsResult( $result );
395 if ( $values ) {
396 $fit = $fit && $result->addValue( 'query', 'badrevids', $values );
397 }
398
399 // Page elements
400 $pages = array();
401
402 // Report any missing titles
403 foreach ( $pageSet->getMissingTitles() as $fakeId => $title ) {
404 $vals = array();
405 ApiQueryBase::addTitleInfo( $vals, $title );
406 $vals['missing'] = true;
407 $pages[$fakeId] = $vals;
408 }
409 // Report any invalid titles
410 foreach ( $pageSet->getInvalidTitlesAndReasons() as $fakeId => $data ) {
411 $pages[$fakeId] = $data + array( 'invalid' => true );
412 }
413 // Report any missing page ids
414 foreach ( $pageSet->getMissingPageIDs() as $pageid ) {
415 $pages[$pageid] = array(
416 'pageid' => $pageid,
417 'missing' => true
418 );
419 }
420 // Report special pages
421 /** @var $title Title */
422 foreach ( $pageSet->getSpecialTitles() as $fakeId => $title ) {
423 $vals = array();
424 ApiQueryBase::addTitleInfo( $vals, $title );
425 $vals['special'] = true;
426 if ( $title->isSpecialPage() &&
427 !SpecialPageFactory::exists( $title->getDBkey() )
428 ) {
429 $vals['missing'] = true;
430 } elseif ( $title->getNamespace() == NS_MEDIA &&
431 !wfFindFile( $title )
432 ) {
433 $vals['missing'] = true;
434 }
435 $pages[$fakeId] = $vals;
436 }
437
438 // Output general page information for found titles
439 foreach ( $pageSet->getGoodTitles() as $pageid => $title ) {
440 $vals = array();
441 $vals['pageid'] = $pageid;
442 ApiQueryBase::addTitleInfo( $vals, $title );
443 $pages[$pageid] = $vals;
444 }
445
446 if ( count( $pages ) ) {
447 $pageSet->populateGeneratorData( $pages );
448 ApiResult::setArrayType( $pages, 'BCarray' );
449
450 if ( $this->mParams['indexpageids'] ) {
451 $pageIDs = array_keys( ApiResult::stripMetadataNonRecursive( $pages ) );
452 // json treats all map keys as strings - converting to match
453 $pageIDs = array_map( 'strval', $pageIDs );
454 ApiResult::setIndexedTagName( $pageIDs, 'id' );
455 $fit = $fit && $result->addValue( 'query', 'pageids', $pageIDs );
456 }
457
458 ApiResult::setIndexedTagName( $pages, 'page' );
459 $fit = $fit && $result->addValue( 'query', 'pages', $pages );
460 }
461
462 if ( !$fit ) {
463 $this->dieUsage(
464 'The value of $wgAPIMaxResultSize on this wiki is ' .
465 'too small to hold basic result information',
466 'badconfig'
467 );
468 }
469
470 if ( $this->mParams['export'] ) {
471 $this->doExport( $pageSet, $result );
472 }
473 }
474
475 /**
476 * This method is called by the generator base when generator in the smart-continue
477 * mode tries to set 'query-continue' value. ApiQuery stores those values separately
478 * until the post-processing when it is known if the generation should continue or repeat.
479 * @deprecated since 1.24
480 * @param ApiQueryGeneratorBase $module Generator module
481 * @param string $paramName
482 * @param mixed $paramValue
483 * @return bool True if processed, false if this is a legacy continue
484 */
485 public function setGeneratorContinue( $module, $paramName, $paramValue ) {
486 wfDeprecated( __METHOD__, '1.24' );
487 $this->getContinuationManager()->addGeneratorContinueParam( $module, $paramName, $paramValue );
488 return $this->getParameter( 'continue' ) !== null;
489 }
490
491 /**
492 * @param ApiPageSet $pageSet Pages to be exported
493 * @param ApiResult $result Result to output to
494 */
495 private function doExport( $pageSet, $result ) {
496 $exportTitles = array();
497 $titles = $pageSet->getGoodTitles();
498 if ( count( $titles ) ) {
499 $user = $this->getUser();
500 /** @var $title Title */
501 foreach ( $titles as $title ) {
502 if ( $title->userCan( 'read', $user ) ) {
503 $exportTitles[] = $title;
504 }
505 }
506 }
507
508 $exporter = new WikiExporter( $this->getDB() );
509 // WikiExporter writes to stdout, so catch its
510 // output with an ob
511 ob_start();
512 $exporter->openStream();
513 foreach ( $exportTitles as $title ) {
514 $exporter->pageByTitle( $title );
515 }
516 $exporter->closeStream();
517 $exportxml = ob_get_contents();
518 ob_end_clean();
519
520 // Don't check the size of exported stuff
521 // It's not continuable, so it would cause more
522 // problems than it'd solve
523 if ( $this->mParams['exportnowrap'] ) {
524 $result->reset();
525 // Raw formatter will handle this
526 $result->addValue( null, 'text', $exportxml, ApiResult::NO_SIZE_CHECK );
527 $result->addValue( null, 'mime', 'text/xml', ApiResult::NO_SIZE_CHECK );
528 } else {
529 $result->addValue( 'query', 'export', $exportxml, ApiResult::NO_SIZE_CHECK );
530 $result->addValue( 'query', ApiResult::META_BC_SUBELEMENTS, array( 'export' ) );
531 }
532 }
533
534 public function getAllowedParams( $flags = 0 ) {
535 $result = array(
536 'prop' => array(
537 ApiBase::PARAM_ISMULTI => true,
538 ApiBase::PARAM_TYPE => 'submodule',
539 ),
540 'list' => array(
541 ApiBase::PARAM_ISMULTI => true,
542 ApiBase::PARAM_TYPE => 'submodule',
543 ),
544 'meta' => array(
545 ApiBase::PARAM_ISMULTI => true,
546 ApiBase::PARAM_TYPE => 'submodule',
547 ),
548 'indexpageids' => false,
549 'export' => false,
550 'exportnowrap' => false,
551 'iwurl' => false,
552 'continue' => null,
553 'rawcontinue' => false,
554 );
555 if ( $flags ) {
556 $result += $this->getPageSet()->getFinalParams( $flags );
557 }
558
559 return $result;
560 }
561
562 /**
563 * Override the parent to generate help messages for all available query modules.
564 * @deprecated since 1.25
565 * @return string
566 */
567 public function makeHelpMsg() {
568 wfDeprecated( __METHOD__, '1.25' );
569
570 // Use parent to make default message for the query module
571 $msg = parent::makeHelpMsg();
572
573 $querySeparator = str_repeat( '--- ', 12 );
574 $moduleSeparator = str_repeat( '*** ', 14 );
575 $msg .= "\n$querySeparator Query: Prop $querySeparator\n\n";
576 $msg .= $this->makeHelpMsgHelper( 'prop' );
577 $msg .= "\n$querySeparator Query: List $querySeparator\n\n";
578 $msg .= $this->makeHelpMsgHelper( 'list' );
579 $msg .= "\n$querySeparator Query: Meta $querySeparator\n\n";
580 $msg .= $this->makeHelpMsgHelper( 'meta' );
581 $msg .= "\n\n$moduleSeparator Modules: continuation $moduleSeparator\n\n";
582
583 return $msg;
584 }
585
586 /**
587 * For all modules of a given group, generate help messages and join them together
588 * @deprecated since 1.25
589 * @param string $group Module group
590 * @return string
591 */
592 private function makeHelpMsgHelper( $group ) {
593 $moduleDescriptions = array();
594
595 $moduleNames = $this->mModuleMgr->getNames( $group );
596 sort( $moduleNames );
597 foreach ( $moduleNames as $name ) {
598 /**
599 * @var $module ApiQueryBase
600 */
601 $module = $this->mModuleMgr->getModule( $name );
602
603 $msg = ApiMain::makeHelpMsgHeader( $module, $group );
604 $msg2 = $module->makeHelpMsg();
605 if ( $msg2 !== false ) {
606 $msg .= $msg2;
607 }
608 if ( $module instanceof ApiQueryGeneratorBase ) {
609 $msg .= "Generator:\n This module may be used as a generator\n";
610 }
611 $moduleDescriptions[] = $msg;
612 }
613
614 return implode( "\n", $moduleDescriptions );
615 }
616
617 public function shouldCheckMaxlag() {
618 return true;
619 }
620
621 protected function getExamplesMessages() {
622 return array(
623 'action=query&prop=revisions&meta=siteinfo&' .
624 'titles=Main%20Page&rvprop=user|comment&continue='
625 => 'apihelp-query-example-revisions',
626 'action=query&generator=allpages&gapprefix=API/&prop=revisions&continue='
627 => 'apihelp-query-example-allpages',
628 );
629 }
630
631 public function getHelpUrls() {
632 return array(
633 'https://www.mediawiki.org/wiki/API:Query',
634 'https://www.mediawiki.org/wiki/API:Meta',
635 'https://www.mediawiki.org/wiki/API:Properties',
636 'https://www.mediawiki.org/wiki/API:Lists',
637 );
638 }
639 }