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 parameters given,
33 * it will create a list of titles to work on (an instance of the ApiPageSet object)
34 * instantiate and execute various property/list/meta modules,
35 * and assemble all resulting data into a single ApiResult object.
37 * In the generator mode, a generator will be first executed to populate a second ApiPageSet object,
38 * 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',
60 private $mQueryListModules = array (
61 'allpages' => 'ApiQueryAllpages',
62 'alllinks' => 'ApiQueryAllLinks',
63 'allusers' => 'ApiQueryAllUsers',
64 'backlinks' => 'ApiQueryBacklinks',
65 'categorymembers' => 'ApiQueryCategoryMembers',
66 'embeddedin' => 'ApiQueryBacklinks',
67 'imageusage' => 'ApiQueryBacklinks',
68 'logevents' => 'ApiQueryLogEvents',
69 'recentchanges' => 'ApiQueryRecentChanges',
70 'search' => 'ApiQuerySearch',
71 'usercontribs' => 'ApiQueryContributions',
72 'watchlist' => 'ApiQueryWatchlist',
73 'exturlusage' => 'ApiQueryExtLinksUsage',
76 private $mQueryMetaModules = array (
77 'siteinfo' => 'ApiQuerySiteinfo',
78 'userinfo' => 'ApiQueryUserInfo',
79 'allmessages' => 'ApiQueryAllmessages',
82 private $mSlaveDB = null;
83 private $mNamedDB = array();
85 public function __construct($main, $action) {
86 parent
:: __construct($main, $action);
88 // Allow custom modules to be added in LocalSettings.php
89 global $wgApiQueryPropModules, $wgApiQueryListModules, $wgApiQueryMetaModules;
90 self
:: appendUserModules($this->mQueryPropModules
, $wgApiQueryPropModules);
91 self
:: appendUserModules($this->mQueryListModules
, $wgApiQueryListModules);
92 self
:: appendUserModules($this->mQueryMetaModules
, $wgApiQueryMetaModules);
94 $this->mPropModuleNames
= array_keys($this->mQueryPropModules
);
95 $this->mListModuleNames
= array_keys($this->mQueryListModules
);
96 $this->mMetaModuleNames
= array_keys($this->mQueryMetaModules
);
98 // Allow the entire list of modules at first,
99 // but during module instantiation check if it can be used as a generator.
100 $this->mAllowedGenerators
= array_merge($this->mListModuleNames
, $this->mPropModuleNames
);
104 * Helper function to append any add-in modules to the list
106 private static function appendUserModules(&$modules, $newModules) {
107 if (is_array( $newModules )) {
108 foreach ( $newModules as $moduleName => $moduleClass) {
109 $modules[$moduleName] = $moduleClass;
115 * Gets a default slave database connection object
117 public function getDB() {
118 if (!isset ($this->mSlaveDB
)) {
119 $this->profileDBIn();
120 $this->mSlaveDB
= wfGetDB(DB_SLAVE
);
121 $this->profileDBOut();
123 return $this->mSlaveDB
;
127 * Get the query database connection with the given name.
128 * If no such connection has been requested before, it will be created.
129 * Subsequent calls with the same $name will return the same connection
130 * as the first, regardless of $db or $groups new values.
132 public function getNamedDB($name, $db, $groups) {
133 if (!array_key_exists($name, $this->mNamedDB
)) {
134 $this->profileDBIn();
135 $this->mNamedDB
[$name] = wfGetDB($db, $groups);
136 $this->profileDBOut();
138 return $this->mNamedDB
[$name];
142 * Gets the set of pages the user has requested (or generated)
144 public function getPageSet() {
145 return $this->mPageSet
;
149 * Query execution happens in the following steps:
150 * #1 Create a PageSet object with any pages requested by the user
151 * #2 If using generator, execute it to get a new PageSet object
152 * #3 Instantiate all requested modules.
153 * This way the PageSet object will know what shared data is required,
154 * and minimize DB calls.
155 * #4 Output all normalization and redirect resolution information
156 * #5 Execute all requested modules
158 public function execute() {
160 $this->params
= $this->extractRequestParams();
161 $this->redirects
= $this->params
['redirects'];
166 $this->mPageSet
= new ApiPageSet($this, $this->redirects
);
169 // Instantiate requested modules
172 $this->InstantiateModules($modules, 'prop', $this->mQueryPropModules
);
173 $this->InstantiateModules($modules, 'list', $this->mQueryListModules
);
174 $this->InstantiateModules($modules, 'meta', $this->mQueryMetaModules
);
177 // If given, execute generator to substitute user supplied data with generated data.
179 if (isset ($this->params
['generator'])) {
180 $this->executeGeneratorModule($this->params
['generator'], $modules);
182 // Append custom fields and populate page/revision information
183 $this->addCustomFldsToPageSet($modules, $this->mPageSet
);
184 $this->mPageSet
->execute();
188 // Record page information (title, namespace, if exists, etc)
190 $this->outputGeneralPageInfo();
193 // Execute all requested modules.
195 foreach ($modules as $module) {
196 $module->profileIn();
198 $module->profileOut();
203 * Query modules may optimize data requests through the $this->getPageSet() object
204 * by adding extra fields from the page table.
205 * This function will gather all the extra request fields from the modules.
207 private function addCustomFldsToPageSet($modules, $pageSet) {
208 // Query all requested modules.
209 foreach ($modules as $module) {
210 $module->requestExtraData($pageSet);
215 * Create instances of all modules requested by the client
217 private function InstantiateModules(&$modules, $param, $moduleList) {
218 $list = $this->params
[$param];
220 foreach ($list as $moduleName)
221 $modules[] = new $moduleList[$moduleName] ($this, $moduleName);
225 * Appends an element for each page in the current pageSet with the most general
226 * information (id, title), plus any title normalizations and missing title/pageids/revids.
228 private function outputGeneralPageInfo() {
230 $pageSet = $this->getPageSet();
231 $result = $this->getResult();
233 // Title normalizations
234 $normValues = array ();
235 foreach ($pageSet->getNormalizedTitles() as $rawTitleStr => $titleStr) {
236 $normValues[] = array (
237 'from' => $rawTitleStr,
242 if (!empty ($normValues)) {
243 $result->setIndexedTagName($normValues, 'n');
244 $result->addValue('query', 'normalized', $normValues);
248 $intrwValues = array ();
249 foreach ($pageSet->getInterwikiTitles() as $rawTitleStr => $interwikiStr) {
250 $intrwValues[] = array (
251 'title' => $rawTitleStr,
252 'iw' => $interwikiStr
256 if (!empty ($intrwValues)) {
257 $result->setIndexedTagName($intrwValues, 'i');
258 $result->addValue('query', 'interwiki', $intrwValues);
261 // Show redirect information
262 $redirValues = array ();
263 foreach ($pageSet->getRedirectTitles() as $titleStrFrom => $titleStrTo) {
264 $redirValues[] = array (
265 'from' => $titleStrFrom,
270 if (!empty ($redirValues)) {
271 $result->setIndexedTagName($redirValues, 'r');
272 $result->addValue('query', 'redirects', $redirValues);
276 // Missing revision elements
278 $missingRevIDs = $pageSet->getMissingRevisionIDs();
279 if (!empty ($missingRevIDs)) {
281 foreach ($missingRevIDs as $revid) {
282 $revids[$revid] = array (
286 $result->setIndexedTagName($revids, 'rev');
287 $result->addValue('query', 'badrevids', $revids);
295 // Report any missing titles
296 foreach ($pageSet->getMissingTitles() as $fakeId => $title) {
298 ApiQueryBase
:: addTitleInfo($vals, $title);
299 $vals['missing'] = '';
300 $pages[$fakeId] = $vals;
303 // Report any missing page ids
304 foreach ($pageSet->getMissingPageIDs() as $pageid) {
305 $pages[$pageid] = array (
311 // Output general page information for found titles
312 foreach ($pageSet->getGoodTitles() as $pageid => $title) {
314 $vals['pageid'] = $pageid;
315 ApiQueryBase
:: addTitleInfo($vals, $title);
316 $pages[$pageid] = $vals;
319 if (!empty ($pages)) {
321 if ($this->params
['indexpageids']) {
322 $pageIDs = array_keys($pages);
323 // json treats all map keys as strings - converting to match
324 $pageIDs = array_map('strval', $pageIDs);
325 $result->setIndexedTagName($pageIDs, 'id');
326 $result->addValue('query', 'pageids', $pageIDs);
329 $result->setIndexedTagName($pages, 'page');
330 $result->addValue('query', 'pages', $pages);
335 * For generator mode, execute generator, and use its output as new pageSet
337 protected function executeGeneratorModule($generatorName, $modules) {
339 // Find class that implements requested generator
340 if (isset ($this->mQueryListModules
[$generatorName])) {
341 $className = $this->mQueryListModules
[$generatorName];
342 } elseif (isset ($this->mQueryPropModules
[$generatorName])) {
343 $className = $this->mQueryPropModules
[$generatorName];
345 ApiBase
:: dieDebug(__METHOD__
, "Unknown generator=$generatorName");
349 $resultPageSet = new ApiPageSet($this, $this->redirects
);
351 // Create and execute the generator
352 $generator = new $className ($this, $generatorName);
353 if (!$generator instanceof ApiQueryGeneratorBase
)
354 $this->dieUsage("Module $generatorName cannot be used as a generator", "badgenerator");
356 $generator->setGeneratorMode();
358 // Add any additional fields modules may need
359 $generator->requestExtraData($this->mPageSet
);
360 $this->addCustomFldsToPageSet($modules, $resultPageSet);
362 // Populate page information with the original user input
363 $this->mPageSet
->execute();
365 // populate resultPageSet with the generator output
366 $generator->profileIn();
367 $generator->executeGenerator($resultPageSet);
368 $resultPageSet->finishPageSetGeneration();
369 $generator->profileOut();
371 // Swap the resulting pageset back in
372 $this->mPageSet
= $resultPageSet;
376 * Returns the list of allowed parameters for this module.
377 * Qurey module also lists all ApiPageSet parameters as its own.
379 protected function getAllowedParams() {
382 ApiBase
:: PARAM_ISMULTI
=> true,
383 ApiBase
:: PARAM_TYPE
=> $this->mPropModuleNames
386 ApiBase
:: PARAM_ISMULTI
=> true,
387 ApiBase
:: PARAM_TYPE
=> $this->mListModuleNames
390 ApiBase
:: PARAM_ISMULTI
=> true,
391 ApiBase
:: PARAM_TYPE
=> $this->mMetaModuleNames
393 'generator' => array (
394 ApiBase
:: PARAM_TYPE
=> $this->mAllowedGenerators
396 'redirects' => false,
397 'indexpageids' => false,
402 * Override the parent to generate help messages for all available query modules.
404 public function makeHelpMsg() {
408 // Make sure the internal object is empty
409 // (just in case a sub-module decides to optimize during instantiation)
410 $this->mPageSet
= null;
411 $this->mAllowedGenerators
= array(); // Will be repopulated
413 $astriks = str_repeat('--- ', 8);
414 $msg .= "\n$astriks Query: Prop $astriks\n\n";
415 $msg .= $this->makeHelpMsgHelper($this->mQueryPropModules
, 'prop');
416 $msg .= "\n$astriks Query: List $astriks\n\n";
417 $msg .= $this->makeHelpMsgHelper($this->mQueryListModules
, 'list');
418 $msg .= "\n$astriks Query: Meta $astriks\n\n";
419 $msg .= $this->makeHelpMsgHelper($this->mQueryMetaModules
, 'meta');
421 // Perform the base call last because the $this->mAllowedGenerators
422 // will be updated inside makeHelpMsgHelper()
423 // Use parent to make default message for the query module
424 $msg = parent
:: makeHelpMsg() . $msg;
430 * For all modules in $moduleList, generate help messages and join them together
432 private function makeHelpMsgHelper($moduleList, $paramName) {
434 $moduleDscriptions = array ();
436 foreach ($moduleList as $moduleName => $moduleClass) {
437 $module = new $moduleClass ($this, $moduleName, null);
439 $msg = ApiMain
::makeHelpMsgHeader($module, $paramName);
440 $msg2 = $module->makeHelpMsg();
443 if ($module instanceof ApiQueryGeneratorBase
) {
444 $this->mAllowedGenerators
[] = $moduleName;
445 $msg .= "Generator:\n This module may be used as a generator\n";
447 $moduleDscriptions[] = $msg;
450 return implode("\n", $moduleDscriptions);
454 * Override to add extra parameters from PageSet
456 public function makeHelpMsgParameters() {
457 $psModule = new ApiPageSet($this);
458 return $psModule->makeHelpMsgParameters() . parent
:: makeHelpMsgParameters();
461 // @todo should work correctly
462 public function shouldCheckMaxlag() {
466 protected function getParamDescription() {
468 'prop' => 'Which properties to get for the titles/revisions/pageids',
469 'list' => 'Which lists to get',
470 'meta' => 'Which meta data to get about the site',
471 'generator' => 'Use the output of a list as the input for other prop/list/meta items',
472 'redirects' => 'Automatically resolve redirects',
473 'indexpageids' => 'Include an additional pageids section listing all returned page IDs.'
477 protected function getDescription() {
479 'Query API module allows applications to get needed pieces of data from the MediaWiki databases,',
480 'and is loosely based on the Query API interface currently available on all MediaWiki servers.',
481 'All data modifications will first have to use query to acquire a token to prevent abuse from malicious sites.'
485 protected function getExamples() {
487 'api.php?action=query&prop=revisions&meta=siteinfo&titles=Main%20Page&rvprop=user|comment'
491 public function getVersion() {
492 $psModule = new ApiPageSet($this);
494 $vers[] = __CLASS__
. ': $Id$';
495 $vers[] = $psModule->getVersion();