includes/api/ApiMain.php

   1 <?php
   2 /**
   3  * Copyright © 2006 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @defgroup API API
  22  */
  23
  24 use MediaWiki\Logger\LoggerFactory;
  25 use MediaWiki\MediaWikiServices;
  26 use Wikimedia\Timestamp\TimestampException;
  27
  28 /**
  29  * This is the main API class, used for both external and internal processing.
  30  * When executed, it will create the requested formatter object,
  31  * instantiate and execute an object associated with the needed action,
  32  * and use formatter to print results.
  33  * In case of an exception, an error message will be printed using the same formatter.
  34  *
  35  * To use API from another application, run it using FauxRequest object, in which
  36  * case any internal exceptions will not be handled but passed up to the caller.
  37  * After successful execution, use getResult() for the resulting data.
  38  *
  39  * @ingroup API
  40  */
  41 class ApiMain extends ApiBase {
  42         /**
  43          * When no format parameter is given, this format will be used
  44          */
  45         const API_DEFAULT_FORMAT = 'jsonfm';
  46
  47         /**
  48          * When no uselang parameter is given, this language will be used
  49          */
  50         const API_DEFAULT_USELANG = 'user';
  51
  52         /**
  53          * List of available modules: action name => module class
  54          */
  55         private static $Modules = [
  56                 'login' => ApiLogin::class,
  57                 'clientlogin' => ApiClientLogin::class,
  58                 'logout' => ApiLogout::class,
  59                 'createaccount' => ApiAMCreateAccount::class,
  60                 'linkaccount' => ApiLinkAccount::class,
  61                 'unlinkaccount' => ApiRemoveAuthenticationData::class,
  62                 'changeauthenticationdata' => ApiChangeAuthenticationData::class,
  63                 'removeauthenticationdata' => ApiRemoveAuthenticationData::class,
  64                 'resetpassword' => ApiResetPassword::class,
  65                 'query' => ApiQuery::class,
  66                 'expandtemplates' => ApiExpandTemplates::class,
  67                 'parse' => ApiParse::class,
  68                 'stashedit' => ApiStashEdit::class,
  69                 'opensearch' => ApiOpenSearch::class,
  70                 'feedcontributions' => ApiFeedContributions::class,
  71                 'feedrecentchanges' => ApiFeedRecentChanges::class,
  72                 'feedwatchlist' => ApiFeedWatchlist::class,
  73                 'help' => ApiHelp::class,
  74                 'paraminfo' => ApiParamInfo::class,
  75                 'rsd' => ApiRsd::class,
  76                 'compare' => ApiComparePages::class,
  77                 'tokens' => ApiTokens::class,
  78                 'checktoken' => ApiCheckToken::class,
  79                 'cspreport' => ApiCSPReport::class,
  80                 'validatepassword' => ApiValidatePassword::class,
  81
  82                 // Write modules
  83                 'purge' => ApiPurge::class,
  84                 'setnotificationtimestamp' => ApiSetNotificationTimestamp::class,
  85                 'rollback' => ApiRollback::class,
  86                 'delete' => ApiDelete::class,
  87                 'undelete' => ApiUndelete::class,
  88                 'protect' => ApiProtect::class,
  89                 'block' => ApiBlock::class,
  90                 'unblock' => ApiUnblock::class,
  91                 'move' => ApiMove::class,
  92                 'edit' => ApiEditPage::class,
  93                 'upload' => ApiUpload::class,
  94                 'filerevert' => ApiFileRevert::class,
  95                 'emailuser' => ApiEmailUser::class,
  96                 'watch' => ApiWatch::class,
  97                 'patrol' => ApiPatrol::class,
  98                 'import' => ApiImport::class,
  99                 'clearhasmsg' => ApiClearHasMsg::class,
 100                 'userrights' => ApiUserrights::class,
 101                 'options' => ApiOptions::class,
 102                 'imagerotate' => ApiImageRotate::class,
 103                 'revisiondelete' => ApiRevisionDelete::class,
 104                 'managetags' => ApiManageTags::class,
 105                 'tag' => ApiTag::class,
 106                 'mergehistory' => ApiMergeHistory::class,
 107                 'setpagelanguage' => ApiSetPageLanguage::class,
 108         ];
 109
 110         /**
 111          * List of available formats: format name => format class
 112          */
 113         private static $Formats = [
 114                 'json' => ApiFormatJson::class,
 115                 'jsonfm' => ApiFormatJson::class,
 116                 'php' => ApiFormatPhp::class,
 117                 'phpfm' => ApiFormatPhp::class,
 118                 'xml' => ApiFormatXml::class,
 119                 'xmlfm' => ApiFormatXml::class,
 120                 'rawfm' => ApiFormatJson::class,
 121                 'none' => ApiFormatNone::class,
 122         ];
 123
 124         /**
 125          * List of user roles that are specifically relevant to the API.
 126          * [ 'right' => [ 'msg'    => 'Some message with a $1',
 127          *                'params' => [ $someVarToSubst ] ],
 128          * ];
 129          */
 130         private static $mRights = [
 131                 'writeapi' => [
 132                         'msg' => 'right-writeapi',
 133                         'params' => []
 134                 ],
 135                 'apihighlimits' => [
 136                         'msg' => 'api-help-right-apihighlimits',
 137                         'params' => [ ApiBase::LIMIT_SML2, ApiBase::LIMIT_BIG2 ]
 138                 ]
 139         ];
 140
 141         /**
 142          * @var ApiFormatBase
 143          */
 144         private $mPrinter;
 145
 146         private $mModuleMgr, $mResult, $mErrorFormatter = null;
 147         /** @var ApiContinuationManager|null */
 148         private $mContinuationManager;
 149         private $mAction;
 150         private $mEnableWrite;
 151         private $mInternalMode, $mSquidMaxage;
 152         /** @var ApiBase */
 153         private $mModule;
 154
 155         private $mCacheMode = 'private';
 156         private $mCacheControl = [];
 157         private $mParamsUsed = [];
 158         private $mParamsSensitive = [];
 159
 160         /** @var bool|null Cached return value from self::lacksSameOriginSecurity() */
 161         private $lacksSameOriginSecurity = null;
 162
 163         /**
 164          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 165          *
 166          * @param IContextSource|WebRequest|null $context If this is an instance of
 167          *    FauxRequest, errors are thrown and no printing occurs
 168          * @param bool $enableWrite Should be set to true if the api may modify data
 169          */
 170         public function __construct( $context = null, $enableWrite = false ) {
 171                 if ( $context === null ) {
 172                         $context = RequestContext::getMain();
 173                 } elseif ( $context instanceof WebRequest ) {
 174                         // BC for pre-1.19
 175                         $request = $context;
 176                         $context = RequestContext::getMain();
 177                 }
 178                 // We set a derivative context so we can change stuff later
 179                 $this->setContext( new DerivativeContext( $context ) );
 180
 181                 if ( isset( $request ) ) {
 182                         $this->getContext()->setRequest( $request );
 183                 } else {
 184                         $request = $this->getRequest();
 185                 }
 186
 187                 $this->mInternalMode = ( $request instanceof FauxRequest );
 188
 189                 // Special handling for the main module: $parent === $this
 190                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 191
 192                 $config = $this->getConfig();
 193
 194                 if ( !$this->mInternalMode ) {
 195                         // Log if a request with a non-whitelisted Origin header is seen
 196                         // with session cookies.
 197                         $originHeader = $request->getHeader( 'Origin' );
 198                         if ( $originHeader === false ) {
 199                                 $origins = [];
 200                         } else {
 201                                 $originHeader = trim( $originHeader );
 202                                 $origins = preg_split( '/\s+/', $originHeader );
 203                         }
 204                         $sessionCookies = array_intersect(
 205                                 array_keys( $_COOKIE ),
 206                                 MediaWiki\Session\SessionManager::singleton()->getVaryCookies()
 207                         );
 208                         if ( $origins && $sessionCookies && (
 209                                 count( $origins ) !== 1 || !self::matchOrigin(
 210                                         $origins[0],
 211                                         $config->get( 'CrossSiteAJAXdomains' ),
 212                                         $config->get( 'CrossSiteAJAXdomainExceptions' )
 213                                 )
 214                         ) ) {
 215                                 LoggerFactory::getInstance( 'cors' )->warning(
 216                                         'Non-whitelisted CORS request with session cookies', [
 217                                                 'origin' => $originHeader,
 218                                                 'cookies' => $sessionCookies,
 219                                                 'ip' => $request->getIP(),
 220                                                 'userAgent' => $this->getUserAgent(),
 221                                                 'wiki' => wfWikiID(),
 222                                         ]
 223                                 );
 224                         }
 225
 226                         // If we're in a mode that breaks the same-origin policy, strip
 227                         // user credentials for security.
 228                         if ( $this->lacksSameOriginSecurity() ) {
 229                                 global $wgUser;
 230                                 wfDebug( "API: stripping user credentials when the same-origin policy is not applied\n" );
 231                                 $wgUser = new User();
 232                                 $this->getContext()->setUser( $wgUser );
 233                                 $request->response()->header( 'MediaWiki-Login-Suppressed: true' );
 234                         }
 235                 }
 236
 237                 $this->mResult = new ApiResult( $this->getConfig()->get( 'APIMaxResultSize' ) );
 238
 239                 // Setup uselang. This doesn't use $this->getParameter()
 240                 // because we're not ready to handle errors yet.
 241                 $uselang = $request->getVal( 'uselang', self::API_DEFAULT_USELANG );
 242                 if ( $uselang === 'user' ) {
 243                         // Assume the parent context is going to return the user language
 244                         // for uselang=user (see T85635).
 245                 } else {
 246                         if ( $uselang === 'content' ) {
 247                                 global $wgContLang;
 248                                 $uselang = $wgContLang->getCode();
 249                         }
 250                         $code = RequestContext::sanitizeLangCode( $uselang );
 251                         $this->getContext()->setLanguage( $code );
 252                         if ( !$this->mInternalMode ) {
 253                                 global $wgLang;
 254                                 $wgLang = $this->getContext()->getLanguage();
 255                                 RequestContext::getMain()->setLanguage( $wgLang );
 256                         }
 257                 }
 258
 259                 // Set up the error formatter. This doesn't use $this->getParameter()
 260                 // because we're not ready to handle errors yet.
 261                 $errorFormat = $request->getVal( 'errorformat', 'bc' );
 262                 $errorLangCode = $request->getVal( 'errorlang', 'uselang' );
 263                 $errorsUseDB = $request->getCheck( 'errorsuselocal' );
 264                 if ( in_array( $errorFormat, [ 'plaintext', 'wikitext', 'html', 'raw', 'none' ], true ) ) {
 265                         if ( $errorLangCode === 'uselang' ) {
 266                                 $errorLang = $this->getLanguage();
 267                         } elseif ( $errorLangCode === 'content' ) {
 268                                 global $wgContLang;
 269                                 $errorLang = $wgContLang;
 270                         } else {
 271                                 $errorLangCode = RequestContext::sanitizeLangCode( $errorLangCode );
 272                                 $errorLang = Language::factory( $errorLangCode );
 273                         }
 274                         $this->mErrorFormatter = new ApiErrorFormatter(
 275                                 $this->mResult, $errorLang, $errorFormat, $errorsUseDB
 276                         );
 277                 } else {
 278                         $this->mErrorFormatter = new ApiErrorFormatter_BackCompat( $this->mResult );
 279                 }
 280                 $this->mResult->setErrorFormatter( $this->getErrorFormatter() );
 281
 282                 $this->mModuleMgr = new ApiModuleManager( $this );
 283                 $this->mModuleMgr->addModules( self::$Modules, 'action' );
 284                 $this->mModuleMgr->addModules( $config->get( 'APIModules' ), 'action' );
 285                 $this->mModuleMgr->addModules( self::$Formats, 'format' );
 286                 $this->mModuleMgr->addModules( $config->get( 'APIFormatModules' ), 'format' );
 287
 288                 Hooks::run( 'ApiMain::moduleManager', [ $this->mModuleMgr ] );
 289
 290                 $this->mContinuationManager = null;
 291                 $this->mEnableWrite = $enableWrite;
 292
 293                 $this->mSquidMaxage = -1; // flag for executeActionWithErrorHandling()
 294                 $this->mCommit = false;
 295         }
 296
 297         /**
 298          * Return true if the API was started by other PHP code using FauxRequest
 299          * @return bool
 300          */
 301         public function isInternalMode() {
 302                 return $this->mInternalMode;
 303         }
 304
 305         /**
 306          * Get the ApiResult object associated with current request
 307          *
 308          * @return ApiResult
 309          */
 310         public function getResult() {
 311                 return $this->mResult;
 312         }
 313
 314         /**
 315          * Get the security flag for the current request
 316          * @return bool
 317          */
 318         public function lacksSameOriginSecurity() {
 319                 if ( $this->lacksSameOriginSecurity !== null ) {
 320                         return $this->lacksSameOriginSecurity;
 321                 }
 322
 323                 $request = $this->getRequest();
 324
 325                 // JSONP mode
 326                 if ( $request->getVal( 'callback' ) !== null ) {
 327                         $this->lacksSameOriginSecurity = true;
 328                         return true;
 329                 }
 330
 331                 // Anonymous CORS
 332                 if ( $request->getVal( 'origin' ) === '*' ) {
 333                         $this->lacksSameOriginSecurity = true;
 334                         return true;
 335                 }
 336
 337                 // Header to be used from XMLHTTPRequest when the request might
 338                 // otherwise be used for XSS.
 339                 if ( $request->getHeader( 'Treat-as-Untrusted' ) !== false ) {
 340                         $this->lacksSameOriginSecurity = true;
 341                         return true;
 342                 }
 343
 344                 // Allow extensions to override.
 345                 $this->lacksSameOriginSecurity = !Hooks::run( 'RequestHasSameOriginSecurity', [ $request ] );
 346                 return $this->lacksSameOriginSecurity;
 347         }
 348
 349         /**
 350          * Get the ApiErrorFormatter object associated with current request
 351          * @return ApiErrorFormatter
 352          */
 353         public function getErrorFormatter() {
 354                 return $this->mErrorFormatter;
 355         }
 356
 357         /**
 358          * Get the continuation manager
 359          * @return ApiContinuationManager|null
 360          */
 361         public function getContinuationManager() {
 362                 return $this->mContinuationManager;
 363         }
 364
 365         /**
 366          * Set the continuation manager
 367          * @param ApiContinuationManager|null $manager
 368          */
 369         public function setContinuationManager( ApiContinuationManager $manager = null ) {
 370                 if ( $manager !== null && $this->mContinuationManager !== null ) {
 371                         throw new UnexpectedValueException(
 372                                 __METHOD__ . ': tried to set manager from ' . $manager->getSource() .
 373                                 ' when a manager is already set from ' . $this->mContinuationManager->getSource()
 374                         );
 375                 }
 376                 $this->mContinuationManager = $manager;
 377         }
 378
 379         /**
 380          * Get the API module object. Only works after executeAction()
 381          *
 382          * @return ApiBase
 383          */
 384         public function getModule() {
 385                 return $this->mModule;
 386         }
 387
 388         /**
 389          * Get the result formatter object. Only works after setupExecuteAction()
 390          *
 391          * @return ApiFormatBase
 392          */
 393         public function getPrinter() {
 394                 return $this->mPrinter;
 395         }
 396
 397         /**
 398          * Set how long the response should be cached.
 399          *
 400          * @param int $maxage
 401          */
 402         public function setCacheMaxAge( $maxage ) {
 403                 $this->setCacheControl( [
 404                         'max-age' => $maxage,
 405                         's-maxage' => $maxage
 406                 ] );
 407         }
 408
 409         /**
 410          * Set the type of caching headers which will be sent.
 411          *
 412          * @param string $mode One of:
 413          *    - 'public':     Cache this object in public caches, if the maxage or smaxage
 414          *         parameter is set, or if setCacheMaxAge() was called. If a maximum age is
 415          *         not provided by any of these means, the object will be private.
 416          *    - 'private':    Cache this object only in private client-side caches.
 417          *    - 'anon-public-user-private': Make this object cacheable for logged-out
 418          *         users, but private for logged-in users. IMPORTANT: If this is set, it must be
 419          *         set consistently for a given URL, it cannot be set differently depending on
 420          *         things like the contents of the database, or whether the user is logged in.
 421          *
 422          *  If the wiki does not allow anonymous users to read it, the mode set here
 423          *  will be ignored, and private caching headers will always be sent. In other words,
 424          *  the "public" mode is equivalent to saying that the data sent is as public as a page
 425          *  view.
 426          *
 427          *  For user-dependent data, the private mode should generally be used. The
 428          *  anon-public-user-private mode should only be used where there is a particularly
 429          *  good performance reason for caching the anonymous response, but where the
 430          *  response to logged-in users may differ, or may contain private data.
 431          *
 432          *  If this function is never called, then the default will be the private mode.
 433          */
 434         public function setCacheMode( $mode ) {
 435                 if ( !in_array( $mode, [ 'private', 'public', 'anon-public-user-private' ] ) ) {
 436                         wfDebug( __METHOD__ . ": unrecognised cache mode \"$mode\"\n" );
 437
 438                         // Ignore for forwards-compatibility
 439                         return;
 440                 }
 441
 442                 if ( !User::isEveryoneAllowed( 'read' ) ) {
 443                         // Private wiki, only private headers
 444                         if ( $mode !== 'private' ) {
 445                                 wfDebug( __METHOD__ . ": ignoring request for $mode cache mode, private wiki\n" );
 446
 447                                 return;
 448                         }
 449                 }
 450
 451                 if ( $mode === 'public' && $this->getParameter( 'uselang' ) === 'user' ) {
 452                         // User language is used for i18n, so we don't want to publicly
 453                         // cache. Anons are ok, because if they have non-default language
 454                         // then there's an appropriate Vary header set by whatever set
 455                         // their non-default language.
 456                         wfDebug( __METHOD__ . ": downgrading cache mode 'public' to " .
 457                                 "'anon-public-user-private' due to uselang=user\n" );
 458                         $mode = 'anon-public-user-private';
 459                 }
 460
 461                 wfDebug( __METHOD__ . ": setting cache mode $mode\n" );
 462                 $this->mCacheMode = $mode;
 463         }
 464
 465         /**
 466          * Set directives (key/value pairs) for the Cache-Control header.
 467          * Boolean values will be formatted as such, by including or omitting
 468          * without an equals sign.
 469          *
 470          * Cache control values set here will only be used if the cache mode is not
 471          * private, see setCacheMode().
 472          *
 473          * @param array $directives
 474          */
 475         public function setCacheControl( $directives ) {
 476                 $this->mCacheControl = $directives + $this->mCacheControl;
 477         }
 478
 479         /**
 480          * Create an instance of an output formatter by its name
 481          *
 482          * @param string $format
 483          *
 484          * @return ApiFormatBase
 485          */
 486         public function createPrinterByName( $format ) {
 487                 $printer = $this->mModuleMgr->getModule( $format, 'format', /* $ignoreCache */ true );
 488                 if ( $printer === null ) {
 489                         $this->dieWithError(
 490                                 [ 'apierror-unknownformat', wfEscapeWikiText( $format ) ], 'unknown_format'
 491                         );
 492                 }
 493
 494                 return $printer;
 495         }
 496
 497         /**
 498          * Execute api request. Any errors will be handled if the API was called by the remote client.
 499          */
 500         public function execute() {
 501                 if ( $this->mInternalMode ) {
 502                         $this->executeAction();
 503                 } else {
 504                         $this->executeActionWithErrorHandling();
 505                 }
 506         }
 507
 508         /**
 509          * Execute an action, and in case of an error, erase whatever partial results
 510          * have been accumulated, and replace it with an error message and a help screen.
 511          */
 512         protected function executeActionWithErrorHandling() {
 513                 // Verify the CORS header before executing the action
 514                 if ( !$this->handleCORS() ) {
 515                         // handleCORS() has sent a 403, abort
 516                         return;
 517                 }
 518
 519                 // Exit here if the request method was OPTIONS
 520                 // (assume there will be a followup GET or POST)
 521                 if ( $this->getRequest()->getMethod() === 'OPTIONS' ) {
 522                         return;
 523                 }
 524
 525                 // In case an error occurs during data output,
 526                 // clear the output buffer and print just the error information
 527                 $obLevel = ob_get_level();
 528                 ob_start();
 529
 530                 $t = microtime( true );
 531                 $isError = false;
 532                 try {
 533                         $this->executeAction();
 534                         $runTime = microtime( true ) - $t;
 535                         $this->logRequest( $runTime );
 536                         MediaWikiServices::getInstance()->getStatsdDataFactory()->timing(
 537                                 'api.' . $this->mModule->getModuleName() . '.executeTiming', 1000 * $runTime
 538                         );
 539                 } catch ( Exception $e ) {
 540                         $this->handleException( $e );
 541                         $this->logRequest( microtime( true ) - $t, $e );
 542                         $isError = true;
 543                 }
 544
 545                 // Commit DBs and send any related cookies and headers
 546                 MediaWiki::preOutputCommit( $this->getContext() );
 547
 548                 // Send cache headers after any code which might generate an error, to
 549                 // avoid sending public cache headers for errors.
 550                 $this->sendCacheHeaders( $isError );
 551
 552                 // Executing the action might have already messed with the output
 553                 // buffers.
 554                 while ( ob_get_level() > $obLevel ) {
 555                         ob_end_flush();
 556                 }
 557         }
 558
 559         /**
 560          * Handle an exception as an API response
 561          *
 562          * @since 1.23
 563          * @param Exception $e
 564          */
 565         protected function handleException( Exception $e ) {
 566                 // T65145: Rollback any open database transactions
 567                 if ( !( $e instanceof ApiUsageException || $e instanceof UsageException ) ) {
 568                         // UsageExceptions are intentional, so don't rollback if that's the case
 569                         MWExceptionHandler::rollbackMasterChangesAndLog( $e );
 570                 }
 571
 572                 // Allow extra cleanup and logging
 573                 Hooks::run( 'ApiMain::onException', [ $this, $e ] );
 574
 575                 // Handle any kind of exception by outputting properly formatted error message.
 576                 // If this fails, an unhandled exception should be thrown so that global error
 577                 // handler will process and log it.
 578
 579                 $errCodes = $this->substituteResultWithError( $e );
 580
 581                 // Error results should not be cached
 582                 $this->setCacheMode( 'private' );
 583
 584                 $response = $this->getRequest()->response();
 585                 $headerStr = 'MediaWiki-API-Error: ' . implode( ', ', $errCodes );
 586                 $response->header( $headerStr );
 587
 588                 // Reset and print just the error message
 589                 ob_clean();
 590
 591                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 592                 $this->createErrorPrinter();
 593
 594                 $failed = false;
 595                 try {
 596                         $this->printResult( $e->getCode() );
 597                 } catch ( ApiUsageException $ex ) {
 598                         // The error printer itself is failing. Try suppressing its request
 599                         // parameters and redo.
 600                         $failed = true;
 601                         $this->addWarning( 'apiwarn-errorprinterfailed' );
 602                         foreach ( $ex->getStatusValue()->getErrors() as $error ) {
 603                                 try {
 604                                         $this->mPrinter->addWarning( $error );
 605                                 } catch ( Exception $ex2 ) {
 606                                         // WTF?
 607                                         $this->addWarning( $error );
 608                                 }
 609                         }
 610                 } catch ( UsageException $ex ) {
 611                         // The error printer itself is failing. Try suppressing its request
 612                         // parameters and redo.
 613                         $failed = true;
 614                         $this->addWarning(
 615                                 [ 'apiwarn-errorprinterfailed-ex', $ex->getMessage() ], 'errorprinterfailed'
 616                         );
 617                 }
 618                 if ( $failed ) {
 619                         $this->mPrinter = null;
 620                         $this->createErrorPrinter();
 621                         $this->mPrinter->forceDefaultParams();
 622                         if ( $e->getCode() ) {
 623                                 $response->statusHeader( 200 ); // Reset in case the fallback doesn't want a non-200
 624                         }
 625                         $this->printResult( $e->getCode() );
 626                 }
 627         }
 628
 629         /**
 630          * Handle an exception from the ApiBeforeMain hook.
 631          *
 632          * This tries to print the exception as an API response, to be more
 633          * friendly to clients. If it fails, it will rethrow the exception.
 634          *
 635          * @since 1.23
 636          * @param Exception $e
 637          * @throws Exception
 638          */
 639         public static function handleApiBeforeMainException( Exception $e ) {
 640                 ob_start();
 641
 642                 try {
 643                         $main = new self( RequestContext::getMain(), false );
 644                         $main->handleException( $e );
 645                         $main->logRequest( 0, $e );
 646                 } catch ( Exception $e2 ) {
 647                         // Nope, even that didn't work. Punt.
 648                         throw $e;
 649                 }
 650
 651                 // Reset cache headers
 652                 $main->sendCacheHeaders( true );
 653
 654                 ob_end_flush();
 655         }
 656
 657         /**
 658          * Check the &origin= query parameter against the Origin: HTTP header and respond appropriately.
 659          *
 660          * If no origin parameter is present, nothing happens.
 661          * If an origin parameter is present but doesn't match the Origin header, a 403 status code
 662          * is set and false is returned.
 663          * If the parameter and the header do match, the header is checked against $wgCrossSiteAJAXdomains
 664          * and $wgCrossSiteAJAXdomainExceptions, and if the origin qualifies, the appropriate CORS
 665          * headers are set.
 666          * https://www.w3.org/TR/cors/#resource-requests
 667          * https://www.w3.org/TR/cors/#resource-preflight-requests
 668          *
 669          * @return bool False if the caller should abort (403 case), true otherwise (all other cases)
 670          */
 671         protected function handleCORS() {
 672                 $originParam = $this->getParameter( 'origin' ); // defaults to null
 673                 if ( $originParam === null ) {
 674                         // No origin parameter, nothing to do
 675                         return true;
 676                 }
 677
 678                 $request = $this->getRequest();
 679                 $response = $request->response();
 680
 681                 $matchedOrigin = false;
 682                 $allowTiming = false;
 683                 $varyOrigin = true;
 684
 685                 if ( $originParam === '*' ) {
 686                         // Request for anonymous CORS
 687                         // Technically we should check for the presence of an Origin header
 688                         // and not process it as CORS if it's not set, but that would
 689                         // require us to vary on Origin for all 'origin=*' requests which
 690                         // we don't want to do.
 691                         $matchedOrigin = true;
 692                         $allowOrigin = '*';
 693                         $allowCredentials = 'false';
 694                         $varyOrigin = false; // No need to vary
 695                 } else {
 696                         // Non-anonymous CORS, check we allow the domain
 697
 698                         // Origin: header is a space-separated list of origins, check all of them
 699                         $originHeader = $request->getHeader( 'Origin' );
 700                         if ( $originHeader === false ) {
 701                                 $origins = [];
 702                         } else {
 703                                 $originHeader = trim( $originHeader );
 704                                 $origins = preg_split( '/\s+/', $originHeader );
 705                         }
 706
 707                         if ( !in_array( $originParam, $origins ) ) {
 708                                 // origin parameter set but incorrect
 709                                 // Send a 403 response
 710                                 $response->statusHeader( 403 );
 711                                 $response->header( 'Cache-Control: no-cache' );
 712                                 echo "'origin' parameter does not match Origin header\n";
 713
 714                                 return false;
 715                         }
 716
 717                         $config = $this->getConfig();
 718                         $matchedOrigin = count( $origins ) === 1 && self::matchOrigin(
 719                                 $originParam,
 720                                 $config->get( 'CrossSiteAJAXdomains' ),
 721                                 $config->get( 'CrossSiteAJAXdomainExceptions' )
 722                         );
 723
 724                         $allowOrigin = $originHeader;
 725                         $allowCredentials = 'true';
 726                         $allowTiming = $originHeader;
 727                 }
 728
 729                 if ( $matchedOrigin ) {
 730                         $requestedMethod = $request->getHeader( 'Access-Control-Request-Method' );
 731                         $preflight = $request->getMethod() === 'OPTIONS' && $requestedMethod !== false;
 732                         if ( $preflight ) {
 733                                 // This is a CORS preflight request
 734                                 if ( $requestedMethod !== 'POST' && $requestedMethod !== 'GET' ) {
 735                                         // If method is not a case-sensitive match, do not set any additional headers and terminate.
 736                                         $response->header( 'MediaWiki-CORS-Rejection: Unsupported method requested in preflight' );
 737                                         return true;
 738                                 }
 739                                 // We allow the actual request to send the following headers
 740                                 $requestedHeaders = $request->getHeader( 'Access-Control-Request-Headers' );
 741                                 if ( $requestedHeaders !== false ) {
 742                                         if ( !self::matchRequestedHeaders( $requestedHeaders ) ) {
 743                                                 $response->header( 'MediaWiki-CORS-Rejection: Unsupported header requested in preflight' );
 744                                                 return true;
 745                                         }
 746                                         $response->header( 'Access-Control-Allow-Headers: ' . $requestedHeaders );
 747                                 }
 748
 749                                 // We only allow the actual request to be GET or POST
 750                                 $response->header( 'Access-Control-Allow-Methods: POST, GET' );
 751                         } elseif ( $request->getMethod() !== 'POST' && $request->getMethod() !== 'GET' ) {
 752                                 // Unsupported non-preflight method, don't handle it as CORS
 753                                 $response->header(
 754                                         'MediaWiki-CORS-Rejection: Unsupported method for simple request or actual request'
 755                                 );
 756                                 return true;
 757                         }
 758
 759                         $response->header( "Access-Control-Allow-Origin: $allowOrigin" );
 760                         $response->header( "Access-Control-Allow-Credentials: $allowCredentials" );
 761                         // https://www.w3.org/TR/resource-timing/#timing-allow-origin
 762                         if ( $allowTiming !== false ) {
 763                                 $response->header( "Timing-Allow-Origin: $allowTiming" );
 764                         }
 765
 766                         if ( !$preflight ) {
 767                                 $response->header(
 768                                         'Access-Control-Expose-Headers: MediaWiki-API-Error, Retry-After, X-Database-Lag, '
 769                                         . 'MediaWiki-Login-Suppressed'
 770                                 );
 771                         }
 772                 } else {
 773                         $response->header( 'MediaWiki-CORS-Rejection: Origin mismatch' );
 774                 }
 775
 776                 if ( $varyOrigin ) {
 777                         $this->getOutput()->addVaryHeader( 'Origin' );
 778                 }
 779
 780                 return true;
 781         }
 782
 783         /**
 784          * Attempt to match an Origin header against a set of rules and a set of exceptions
 785          * @param string $value Origin header
 786          * @param array $rules Set of wildcard rules
 787          * @param array $exceptions Set of wildcard rules
 788          * @return bool True if $value matches a rule in $rules and doesn't match
 789          *    any rules in $exceptions, false otherwise
 790          */
 791         protected static function matchOrigin( $value, $rules, $exceptions ) {
 792                 foreach ( $rules as $rule ) {
 793                         if ( preg_match( self::wildcardToRegex( $rule ), $value ) ) {
 794                                 // Rule matches, check exceptions
 795                                 foreach ( $exceptions as $exc ) {
 796                                         if ( preg_match( self::wildcardToRegex( $exc ), $value ) ) {
 797                                                 return false;
 798                                         }
 799                                 }
 800
 801                                 return true;
 802                         }
 803                 }
 804
 805                 return false;
 806         }
 807
 808         /**
 809          * Attempt to validate the value of Access-Control-Request-Headers against a list
 810          * of headers that we allow the follow up request to send.
 811          *
 812          * @param string $requestedHeaders Comma seperated list of HTTP headers
 813          * @return bool True if all requested headers are in the list of allowed headers
 814          */
 815         protected static function matchRequestedHeaders( $requestedHeaders ) {
 816                 if ( trim( $requestedHeaders ) === '' ) {
 817                         return true;
 818                 }
 819                 $requestedHeaders = explode( ',', $requestedHeaders );
 820                 $allowedAuthorHeaders = array_flip( [
 821                         /* simple headers (see spec) */
 822                         'accept',
 823                         'accept-language',
 824                         'content-language',
 825                         'content-type',
 826                         /* non-authorable headers in XHR, which are however requested by some UAs */
 827                         'accept-encoding',
 828                         'dnt',
 829                         'origin',
 830                         /* MediaWiki whitelist */
 831                         'api-user-agent',
 832                 ] );
 833                 foreach ( $requestedHeaders as $rHeader ) {
 834                         $rHeader = strtolower( trim( $rHeader ) );
 835                         if ( !isset( $allowedAuthorHeaders[$rHeader] ) ) {
 836                                 wfDebugLog( 'api', 'CORS preflight failed on requested header: ' . $rHeader );
 837                                 return false;
 838                         }
 839                 }
 840                 return true;
 841         }
 842
 843         /**
 844          * Helper function to convert wildcard string into a regex
 845          * '*' => '.*?'
 846          * '?' => '.'
 847          *
 848          * @param string $wildcard String with wildcards
 849          * @return string Regular expression
 850          */
 851         protected static function wildcardToRegex( $wildcard ) {
 852                 $wildcard = preg_quote( $wildcard, '/' );
 853                 $wildcard = str_replace(
 854                         [ '\*', '\?' ],
 855                         [ '.*?', '.' ],
 856                         $wildcard
 857                 );
 858
 859                 return "/^https?:\/\/$wildcard$/";
 860         }
 861
 862         /**
 863          * Send caching headers
 864          * @param bool $isError Whether an error response is being output
 865          * @since 1.26 added $isError parameter
 866          */
 867         protected function sendCacheHeaders( $isError ) {
 868                 $response = $this->getRequest()->response();
 869                 $out = $this->getOutput();
 870
 871                 $out->addVaryHeader( 'Treat-as-Untrusted' );
 872
 873                 $config = $this->getConfig();
 874
 875                 if ( $config->get( 'VaryOnXFP' ) ) {
 876                         $out->addVaryHeader( 'X-Forwarded-Proto' );
 877                 }
 878
 879                 if ( !$isError && $this->mModule &&
 880                         ( $this->getRequest()->getMethod() === 'GET' || $this->getRequest()->getMethod() === 'HEAD' )
 881                 ) {
 882                         $etag = $this->mModule->getConditionalRequestData( 'etag' );
 883                         if ( $etag !== null ) {
 884                                 $response->header( "ETag: $etag" );
 885                         }
 886                         $lastMod = $this->mModule->getConditionalRequestData( 'last-modified' );
 887                         if ( $lastMod !== null ) {
 888                                 $response->header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $lastMod ) );
 889                         }
 890                 }
 891
 892                 // The logic should be:
 893                 // $this->mCacheControl['max-age'] is set?
 894                 //    Use it, the module knows better than our guess.
 895                 // !$this->mModule || $this->mModule->isWriteMode(), and mCacheMode is private?
 896                 //    Use 0 because we can guess caching is probably the wrong thing to do.
 897                 // Use $this->getParameter( 'maxage' ), which already defaults to 0.
 898                 $maxage = 0;
 899                 if ( isset( $this->mCacheControl['max-age'] ) ) {
 900                         $maxage = $this->mCacheControl['max-age'];
 901                 } elseif ( ( $this->mModule && !$this->mModule->isWriteMode() ) ||
 902                         $this->mCacheMode !== 'private'
 903                 ) {
 904                         $maxage = $this->getParameter( 'maxage' );
 905                 }
 906                 $privateCache = 'private, must-revalidate, max-age=' . $maxage;
 907
 908                 if ( $this->mCacheMode == 'private' ) {
 909                         $response->header( "Cache-Control: $privateCache" );
 910                         return;
 911                 }
 912
 913                 $useKeyHeader = $config->get( 'UseKeyHeader' );
 914                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 915                         $out->addVaryHeader( 'Cookie' );
 916                         $response->header( $out->getVaryHeader() );
 917                         if ( $useKeyHeader ) {
 918                                 $response->header( $out->getKeyHeader() );
 919                                 if ( $out->haveCacheVaryCookies() ) {
 920                                         // Logged in, mark this request private
 921                                         $response->header( "Cache-Control: $privateCache" );
 922                                         return;
 923                                 }
 924                                 // Logged out, send normal public headers below
 925                         } elseif ( MediaWiki\Session\SessionManager::getGlobalSession()->isPersistent() ) {
 926                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 927                                 // Mark request private
 928                                 $response->header( "Cache-Control: $privateCache" );
 929
 930                                 return;
 931                         } // else no Key and anonymous, send public headers below
 932                 }
 933
 934                 // Send public headers
 935                 $response->header( $out->getVaryHeader() );
 936                 if ( $useKeyHeader ) {
 937                         $response->header( $out->getKeyHeader() );
 938                 }
 939
 940                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 941                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 942                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 943                 }
 944                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 945                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 946                 }
 947
 948                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 949                         // Public cache not requested
 950                         // Sending a Vary header in this case is harmless, and protects us
 951                         // against conditional calls of setCacheMaxAge().
 952                         $response->header( "Cache-Control: $privateCache" );
 953
 954                         return;
 955                 }
 956
 957                 $this->mCacheControl['public'] = true;
 958
 959                 // Send an Expires header
 960                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 961                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 962                 $response->header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 963
 964                 // Construct the Cache-Control header
 965                 $ccHeader = '';
 966                 $separator = '';
 967                 foreach ( $this->mCacheControl as $name => $value ) {
 968                         if ( is_bool( $value ) ) {
 969                                 if ( $value ) {
 970                                         $ccHeader .= $separator . $name;
 971                                         $separator = ', ';
 972                                 }
 973                         } else {
 974                                 $ccHeader .= $separator . "$name=$value";
 975                                 $separator = ', ';
 976                         }
 977                 }
 978
 979                 $response->header( "Cache-Control: $ccHeader" );
 980         }
 981
 982         /**
 983          * Create the printer for error output
 984          */
 985         private function createErrorPrinter() {
 986                 if ( !isset( $this->mPrinter ) ) {
 987                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 988                         if ( !$this->mModuleMgr->isDefined( $value, 'format' ) ) {
 989                                 $value = self::API_DEFAULT_FORMAT;
 990                         }
 991                         $this->mPrinter = $this->createPrinterByName( $value );
 992                 }
 993
 994                 // Printer may not be able to handle errors. This is particularly
 995                 // likely if the module returns something for getCustomPrinter().
 996                 if ( !$this->mPrinter->canPrintErrors() ) {
 997                         $this->mPrinter = $this->createPrinterByName( self::API_DEFAULT_FORMAT );
 998                 }
 999         }
1000
1001         /**
1002          * Create an error message for the given exception.
1003          *
1004          * If an ApiUsageException, errors/warnings will be extracted from the
1005          * embedded StatusValue.
1006          *
1007          * If a base UsageException, the getMessageArray() method will be used to
1008          * extract the code and English message for a single error (no warnings).
1009          *
1010          * Any other exception will be returned with a generic code and wrapper
1011          * text around the exception's (presumably English) message as a single
1012          * error (no warnings).
1013          *
1014          * @param Exception $e
1015          * @param string $type 'error' or 'warning'
1016          * @return ApiMessage[]
1017          * @since 1.27
1018          */
1019         protected function errorMessagesFromException( $e, $type = 'error' ) {
1020                 $messages = [];
1021                 if ( $e instanceof ApiUsageException ) {
1022                         foreach ( $e->getStatusValue()->getErrorsByType( $type ) as $error ) {
1023                                 $messages[] = ApiMessage::create( $error );
1024                         }
1025                 } elseif ( $type !== 'error' ) {
1026                         // None of the rest have any messages for non-error types
1027                 } elseif ( $e instanceof UsageException ) {
1028                         // User entered incorrect parameters - generate error response
1029                         $data = Wikimedia\quietCall( [ $e, 'getMessageArray' ] );
1030                         $code = $data['code'];
1031                         $info = $data['info'];
1032                         unset( $data['code'], $data['info'] );
1033                         $messages[] = new ApiRawMessage( [ '$1', $info ], $code, $data );
1034                 } else {
1035                         // Something is seriously wrong
1036                         $config = $this->getConfig();
1037                         $class = preg_replace( '#^Wikimedia\\\Rdbms\\\#', '', get_class( $e ) );
1038                         $code = 'internal_api_error_' . $class;
1039                         if ( $config->get( 'ShowExceptionDetails' ) ) {
1040                                 if ( $e instanceof ILocalizedException ) {
1041                                         $msg = $e->getMessageObject();
1042                                 } elseif ( $e instanceof MessageSpecifier ) {
1043                                         $msg = Message::newFromSpecifier( $e );
1044                                 } else {
1045                                         $msg = wfEscapeWikiText( $e->getMessage() );
1046                                 }
1047                                 $params = [ 'apierror-exceptioncaught', WebRequest::getRequestId(), $msg ];
1048                         } else {
1049                                 $params = [ 'apierror-exceptioncaughttype', WebRequest::getRequestId(), get_class( $e ) ];
1050                         }
1051
1052                         $messages[] = ApiMessage::create( $params, $code );
1053                 }
1054                 return $messages;
1055         }
1056
1057         /**
1058          * Replace the result data with the information about an exception.
1059          * @param Exception $e
1060          * @return string[] Error codes
1061          */
1062         protected function substituteResultWithError( $e ) {
1063                 $result = $this->getResult();
1064                 $formatter = $this->getErrorFormatter();
1065                 $config = $this->getConfig();
1066                 $errorCodes = [];
1067
1068                 // Remember existing warnings and errors across the reset
1069                 $errors = $result->getResultData( [ 'errors' ] );
1070                 $warnings = $result->getResultData( [ 'warnings' ] );
1071                 $result->reset();
1072                 if ( $warnings !== null ) {
1073                         $result->addValue( null, 'warnings', $warnings, ApiResult::NO_SIZE_CHECK );
1074                 }
1075                 if ( $errors !== null ) {
1076                         $result->addValue( null, 'errors', $errors, ApiResult::NO_SIZE_CHECK );
1077
1078                         // Collect the copied error codes for the return value
1079                         foreach ( $errors as $error ) {
1080                                 if ( isset( $error['code'] ) ) {
1081                                         $errorCodes[$error['code']] = true;
1082                                 }
1083                         }
1084                 }
1085
1086                 // Add errors from the exception
1087                 $modulePath = $e instanceof ApiUsageException ? $e->getModulePath() : null;
1088                 foreach ( $this->errorMessagesFromException( $e, 'error' ) as $msg ) {
1089                         $errorCodes[$msg->getApiCode()] = true;
1090                         $formatter->addError( $modulePath, $msg );
1091                 }
1092                 foreach ( $this->errorMessagesFromException( $e, 'warning' ) as $msg ) {
1093                         $formatter->addWarning( $modulePath, $msg );
1094                 }
1095
1096                 // Add additional data. Path depends on whether we're in BC mode or not.
1097                 // Data depends on the type of exception.
1098                 if ( $formatter instanceof ApiErrorFormatter_BackCompat ) {
1099                         $path = [ 'error' ];
1100                 } else {
1101                         $path = null;
1102                 }
1103                 if ( $e instanceof ApiUsageException || $e instanceof UsageException ) {
1104                         $link = wfExpandUrl( wfScript( 'api' ) );
1105                         $result->addContentValue(
1106                                 $path,
1107                                 'docref',
1108                                 trim(
1109                                         $this->msg( 'api-usage-docref', $link )->inLanguage( $formatter->getLanguage() )->text()
1110                                         . ' '
1111                                         . $this->msg( 'api-usage-mailinglist-ref' )->inLanguage( $formatter->getLanguage() )->text()
1112                                 )
1113                         );
1114                 } else {
1115                         if ( $config->get( 'ShowExceptionDetails' ) ) {
1116                                 $result->addContentValue(
1117                                         $path,
1118                                         'trace',
1119                                         $this->msg( 'api-exception-trace',
1120                                                 get_class( $e ),
1121                                                 $e->getFile(),
1122                                                 $e->getLine(),
1123                                                 MWExceptionHandler::getRedactedTraceAsString( $e )
1124                                         )->inLanguage( $formatter->getLanguage() )->text()
1125                                 );
1126                         }
1127                 }
1128
1129                 // Add the id and such
1130                 $this->addRequestedFields( [ 'servedby' ] );
1131
1132                 return array_keys( $errorCodes );
1133         }
1134
1135         /**
1136          * Add requested fields to the result
1137          * @param string[] $force Which fields to force even if not requested. Accepted values are:
1138          *  - servedby
1139          */
1140         protected function addRequestedFields( $force = [] ) {
1141                 $result = $this->getResult();
1142
1143                 $requestid = $this->getParameter( 'requestid' );
1144                 if ( $requestid !== null ) {
1145                         $result->addValue( null, 'requestid', $requestid, ApiResult::NO_SIZE_CHECK );
1146                 }
1147
1148                 if ( $this->getConfig()->get( 'ShowHostnames' ) && (
1149                         in_array( 'servedby', $force, true ) || $this->getParameter( 'servedby' )
1150                 ) ) {
1151                         $result->addValue( null, 'servedby', wfHostname(), ApiResult::NO_SIZE_CHECK );
1152                 }
1153
1154                 if ( $this->getParameter( 'curtimestamp' ) ) {
1155                         $result->addValue( null, 'curtimestamp', wfTimestamp( TS_ISO_8601, time() ),
1156                                 ApiResult::NO_SIZE_CHECK );
1157                 }
1158
1159                 if ( $this->getParameter( 'responselanginfo' ) ) {
1160                         $result->addValue( null, 'uselang', $this->getLanguage()->getCode(),
1161                                 ApiResult::NO_SIZE_CHECK );
1162                         $result->addValue( null, 'errorlang', $this->getErrorFormatter()->getLanguage()->getCode(),
1163                                 ApiResult::NO_SIZE_CHECK );
1164                 }
1165         }
1166
1167         /**
1168          * Set up for the execution.
1169          * @return array
1170          */
1171         protected function setupExecuteAction() {
1172                 $this->addRequestedFields();
1173
1174                 $params = $this->extractRequestParams();
1175                 $this->mAction = $params['action'];
1176
1177                 return $params;
1178         }
1179
1180         /**
1181          * Set up the module for response
1182          * @return ApiBase The module that will handle this action
1183          * @throws MWException
1184          * @throws ApiUsageException
1185          */
1186         protected function setupModule() {
1187                 // Instantiate the module requested by the user
1188                 $module = $this->mModuleMgr->getModule( $this->mAction, 'action' );
1189                 if ( $module === null ) {
1190                         // Probably can't happen
1191                         // @codeCoverageIgnoreStart
1192                         $this->dieWithError(
1193                                 [ 'apierror-unknownaction', wfEscapeWikiText( $this->mAction ) ], 'unknown_action'
1194                         );
1195                         // @codeCoverageIgnoreEnd
1196                 }
1197                 $moduleParams = $module->extractRequestParams();
1198
1199                 // Check token, if necessary
1200                 if ( $module->needsToken() === true ) {
1201                         throw new MWException(
1202                                 "Module '{$module->getModuleName()}' must be updated for the new token handling. " .
1203                                 'See documentation for ApiBase::needsToken for details.'
1204                         );
1205                 }
1206                 if ( $module->needsToken() ) {
1207                         if ( !$module->mustBePosted() ) {
1208                                 throw new MWException(
1209                                         "Module '{$module->getModuleName()}' must require POST to use tokens."
1210                                 );
1211                         }
1212
1213                         if ( !isset( $moduleParams['token'] ) ) {
1214                                 // Probably can't happen
1215                                 // @codeCoverageIgnoreStart
1216                                 $module->dieWithError( [ 'apierror-missingparam', 'token' ] );
1217                                 // @codeCoverageIgnoreEnd
1218                         }
1219
1220                         $module->requirePostedParameters( [ 'token' ] );
1221
1222                         if ( !$module->validateToken( $moduleParams['token'], $moduleParams ) ) {
1223                                 $module->dieWithError( 'apierror-badtoken' );
1224                         }
1225                 }
1226
1227                 return $module;
1228         }
1229
1230         /**
1231          * @return array
1232          */
1233         private function getMaxLag() {
1234                 $dbLag = MediaWikiServices::getInstance()->getDBLoadBalancer()->getMaxLag();
1235                 $lagInfo = [
1236                         'host' => $dbLag[0],
1237                         'lag' => $dbLag[1],
1238                         'type' => 'db'
1239                 ];
1240
1241                 $jobQueueLagFactor = $this->getConfig()->get( 'JobQueueIncludeInMaxLagFactor' );
1242                 if ( $jobQueueLagFactor ) {
1243                         // Turn total number of jobs into seconds by using the configured value
1244                         $totalJobs = array_sum( JobQueueGroup::singleton()->getQueueSizes() );
1245                         $jobQueueLag = $totalJobs / (float)$jobQueueLagFactor;
1246                         if ( $jobQueueLag > $lagInfo['lag'] ) {
1247                                 $lagInfo = [
1248                                         'host' => wfHostname(), // XXX: Is there a better value that could be used?
1249                                         'lag' => $jobQueueLag,
1250                                         'type' => 'jobqueue',
1251                                         'jobs' => $totalJobs,
1252                                 ];
1253                         }
1254                 }
1255
1256                 Hooks::runWithoutAbort( 'ApiMaxLagInfo', [ &$lagInfo ] );
1257
1258                 return $lagInfo;
1259         }
1260
1261         /**
1262          * Check the max lag if necessary
1263          * @param ApiBase $module Api module being used
1264          * @param array $params Array an array containing the request parameters.
1265          * @return bool True on success, false should exit immediately
1266          */
1267         protected function checkMaxLag( $module, $params ) {
1268                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
1269                         $maxLag = $params['maxlag'];
1270                         $lagInfo = $this->getMaxLag();
1271                         if ( $lagInfo['lag'] > $maxLag ) {
1272                                 $response = $this->getRequest()->response();
1273
1274                                 $response->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
1275                                 $response->header( 'X-Database-Lag: ' . intval( $lagInfo['lag'] ) );
1276
1277                                 if ( $this->getConfig()->get( 'ShowHostnames' ) ) {
1278                                         $this->dieWithError(
1279                                                 [ 'apierror-maxlag', $lagInfo['lag'], $lagInfo['host'] ],
1280                                                 'maxlag',
1281                                                 $lagInfo
1282                                         );
1283                                 }
1284
1285                                 $this->dieWithError( [ 'apierror-maxlag-generic', $lagInfo['lag'] ], 'maxlag', $lagInfo );
1286                         }
1287                 }
1288
1289                 return true;
1290         }
1291
1292         /**
1293          * Check selected RFC 7232 precondition headers
1294          *
1295          * RFC 7232 envisions a particular model where you send your request to "a
1296          * resource", and for write requests that you can read "the resource" by
1297          * changing the method to GET. When the API receives a GET request, it
1298          * works out even though "the resource" from RFC 7232's perspective might
1299          * be many resources from MediaWiki's perspective. But it totally fails for
1300          * a POST, since what HTTP sees as "the resource" is probably just
1301          * "/api.php" with all the interesting bits in the body.
1302          *
1303          * Therefore, we only support RFC 7232 precondition headers for GET (and
1304          * HEAD). That means we don't need to bother with If-Match and
1305          * If-Unmodified-Since since they only apply to modification requests.
1306          *
1307          * And since we don't support Range, If-Range is ignored too.
1308          *
1309          * @since 1.26
1310          * @param ApiBase $module Api module being used
1311          * @return bool True on success, false should exit immediately
1312          */
1313         protected function checkConditionalRequestHeaders( $module ) {
1314                 if ( $this->mInternalMode ) {
1315                         // No headers to check in internal mode
1316                         return true;
1317                 }
1318
1319                 if ( $this->getRequest()->getMethod() !== 'GET' && $this->getRequest()->getMethod() !== 'HEAD' ) {
1320                         // Don't check POSTs
1321                         return true;
1322                 }
1323
1324                 $return304 = false;
1325
1326                 $ifNoneMatch = array_diff(
1327                         $this->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST ) ?: [],
1328                         [ '' ]
1329                 );
1330                 if ( $ifNoneMatch ) {
1331                         if ( $ifNoneMatch === [ '*' ] ) {
1332                                 // API responses always "exist"
1333                                 $etag = '*';
1334                         } else {
1335                                 $etag = $module->getConditionalRequestData( 'etag' );
1336                         }
1337                 }
1338                 if ( $ifNoneMatch && $etag !== null ) {
1339                         $test = substr( $etag, 0, 2 ) === 'W/' ? substr( $etag, 2 ) : $etag;
1340                         $match = array_map( function ( $s ) {
1341                                 return substr( $s, 0, 2 ) === 'W/' ? substr( $s, 2 ) : $s;
1342                         }, $ifNoneMatch );
1343                         $return304 = in_array( $test, $match, true );
1344                 } else {
1345                         $value = trim( $this->getRequest()->getHeader( 'If-Modified-Since' ) );
1346
1347                         // Some old browsers sends sizes after the date, like this:
1348                         //  Wed, 20 Aug 2003 06:51:19 GMT; length=5202
1349                         // Ignore that.
1350                         $i = strpos( $value, ';' );
1351                         if ( $i !== false ) {
1352                                 $value = trim( substr( $value, 0, $i ) );
1353                         }
1354
1355                         if ( $value !== '' ) {
1356                                 try {
1357                                         $ts = new MWTimestamp( $value );
1358                                         if (
1359                                                 // RFC 7231 IMF-fixdate
1360                                                 $ts->getTimestamp( TS_RFC2822 ) === $value ||
1361                                                 // RFC 850
1362                                                 $ts->format( 'l, d-M-y H:i:s' ) . ' GMT' === $value ||
1363                                                 // asctime (with and without space-padded day)
1364                                                 $ts->format( 'D M j H:i:s Y' ) === $value ||
1365                                                 $ts->format( 'D M  j H:i:s Y' ) === $value
1366                                         ) {
1367                                                 $lastMod = $module->getConditionalRequestData( 'last-modified' );
1368                                                 if ( $lastMod !== null ) {
1369                                                         // Mix in some MediaWiki modification times
1370                                                         $modifiedTimes = [
1371                                                                 'page' => $lastMod,
1372                                                                 'user' => $this->getUser()->getTouched(),
1373                                                                 'epoch' => $this->getConfig()->get( 'CacheEpoch' ),
1374                                                         ];
1375                                                         if ( $this->getConfig()->get( 'UseSquid' ) ) {
1376                                                                 // T46570: the core page itself may not change, but resources might
1377                                                                 $modifiedTimes['sepoch'] = wfTimestamp(
1378                                                                         TS_MW, time() - $this->getConfig()->get( 'SquidMaxage' )
1379                                                                 );
1380                                                         }
1381                                                         Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this->getOutput() ] );
1382                                                         $lastMod = max( $modifiedTimes );
1383                                                         $return304 = wfTimestamp( TS_MW, $lastMod ) <= $ts->getTimestamp( TS_MW );
1384                                                 }
1385                                         }
1386                                 } catch ( TimestampException $e ) {
1387                                         // Invalid timestamp, ignore it
1388                                 }
1389                         }
1390                 }
1391
1392                 if ( $return304 ) {
1393                         $this->getRequest()->response()->statusHeader( 304 );
1394
1395                         // Avoid outputting the compressed representation of a zero-length body
1396                         Wikimedia\suppressWarnings();
1397                         ini_set( 'zlib.output_compression', 0 );
1398                         Wikimedia\restoreWarnings();
1399                         wfClearOutputBuffers();
1400
1401                         return false;
1402                 }
1403
1404                 return true;
1405         }
1406
1407         /**
1408          * Check for sufficient permissions to execute
1409          * @param ApiBase $module An Api module
1410          */
1411         protected function checkExecutePermissions( $module ) {
1412                 $user = $this->getUser();
1413                 if ( $module->isReadMode() && !User::isEveryoneAllowed( 'read' ) &&
1414                         !$user->isAllowed( 'read' )
1415                 ) {
1416                         $this->dieWithError( 'apierror-readapidenied' );
1417                 }
1418
1419                 if ( $module->isWriteMode() ) {
1420                         if ( !$this->mEnableWrite ) {
1421                                 $this->dieWithError( 'apierror-noapiwrite' );
1422                         } elseif ( !$user->isAllowed( 'writeapi' ) ) {
1423                                 $this->dieWithError( 'apierror-writeapidenied' );
1424                         } elseif ( $this->getRequest()->getHeader( 'Promise-Non-Write-API-Action' ) ) {
1425                                 $this->dieWithError( 'apierror-promised-nonwrite-api' );
1426                         }
1427
1428                         $this->checkReadOnly( $module );
1429                 }
1430
1431                 // Allow extensions to stop execution for arbitrary reasons.
1432                 $message = 'hookaborted';
1433                 if ( !Hooks::run( 'ApiCheckCanExecute', [ $module, $user, &$message ] ) ) {
1434                         $this->dieWithError( $message );
1435                 }
1436         }
1437
1438         /**
1439          * Check if the DB is read-only for this user
1440          * @param ApiBase $module An Api module
1441          */
1442         protected function checkReadOnly( $module ) {
1443                 if ( wfReadOnly() ) {
1444                         $this->dieReadOnly();
1445                 }
1446
1447                 if ( $module->isWriteMode()
1448                         && $this->getUser()->isBot()
1449                         && MediaWikiServices::getInstance()->getDBLoadBalancer()->getServerCount() > 1
1450                 ) {
1451                         $this->checkBotReadOnly();
1452                 }
1453         }
1454
1455         /**
1456          * Check whether we are readonly for bots
1457          */
1458         private function checkBotReadOnly() {
1459                 // Figure out how many servers have passed the lag threshold
1460                 $numLagged = 0;
1461                 $lagLimit = $this->getConfig()->get( 'APIMaxLagThreshold' );
1462                 $laggedServers = [];
1463                 $loadBalancer = MediaWikiServices::getInstance()->getDBLoadBalancer();
1464                 foreach ( $loadBalancer->getLagTimes() as $serverIndex => $lag ) {
1465                         if ( $lag > $lagLimit ) {
1466                                 ++$numLagged;
1467                                 $laggedServers[] = $loadBalancer->getServerName( $serverIndex ) . " ({$lag}s)";
1468                         }
1469                 }
1470
1471                 // If a majority of replica DBs are too lagged then disallow writes
1472                 $replicaCount = $loadBalancer->getServerCount() - 1;
1473                 if ( $numLagged >= ceil( $replicaCount / 2 ) ) {
1474                         $laggedServers = implode( ', ', $laggedServers );
1475                         wfDebugLog(
1476                                 'api-readonly',
1477                                 "Api request failed as read only because the following DBs are lagged: $laggedServers"
1478                         );
1479
1480                         $this->dieWithError(
1481                                 'readonly_lag',
1482                                 'readonly',
1483                                 [ 'readonlyreason' => "Waiting for $numLagged lagged database(s)" ]
1484                         );
1485                 }
1486         }
1487
1488         /**
1489          * Check asserts of the user's rights
1490          * @param array $params
1491          */
1492         protected function checkAsserts( $params ) {
1493                 if ( isset( $params['assert'] ) ) {
1494                         $user = $this->getUser();
1495                         switch ( $params['assert'] ) {
1496                                 case 'user':
1497                                         if ( $user->isAnon() ) {
1498                                                 $this->dieWithError( 'apierror-assertuserfailed' );
1499                                         }
1500                                         break;
1501                                 case 'bot':
1502                                         if ( !$user->isAllowed( 'bot' ) ) {
1503                                                 $this->dieWithError( 'apierror-assertbotfailed' );
1504                                         }
1505                                         break;
1506                         }
1507                 }
1508                 if ( isset( $params['assertuser'] ) ) {
1509                         $assertUser = User::newFromName( $params['assertuser'], false );
1510                         if ( !$assertUser || !$this->getUser()->equals( $assertUser ) ) {
1511                                 $this->dieWithError(
1512                                         [ 'apierror-assertnameduserfailed', wfEscapeWikiText( $params['assertuser'] ) ]
1513                                 );
1514                         }
1515                 }
1516         }
1517
1518         /**
1519          * Check POST for external response and setup result printer
1520          * @param ApiBase $module An Api module
1521          * @param array $params An array with the request parameters
1522          */
1523         protected function setupExternalResponse( $module, $params ) {
1524                 $request = $this->getRequest();
1525                 if ( !$request->wasPosted() && $module->mustBePosted() ) {
1526                         // Module requires POST. GET request might still be allowed
1527                         // if $wgDebugApi is true, otherwise fail.
1528                         $this->dieWithErrorOrDebug( [ 'apierror-mustbeposted', $this->mAction ] );
1529                 }
1530
1531                 // See if custom printer is used
1532                 $this->mPrinter = $module->getCustomPrinter();
1533                 if ( is_null( $this->mPrinter ) ) {
1534                         // Create an appropriate printer
1535                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
1536                 }
1537
1538                 if ( $request->getProtocol() === 'http' && (
1539                         $request->getSession()->shouldForceHTTPS() ||
1540                         ( $this->getUser()->isLoggedIn() &&
1541                                 $this->getUser()->requiresHTTPS() )
1542                 ) ) {
1543                         $this->addDeprecation( 'apiwarn-deprecation-httpsexpected', 'https-expected' );
1544                 }
1545         }
1546
1547         /**
1548          * Execute the actual module, without any error handling
1549          */
1550         protected function executeAction() {
1551                 $params = $this->setupExecuteAction();
1552
1553                 // Check asserts early so e.g. errors in parsing a module's parameters due to being
1554                 // logged out don't override the client's intended "am I logged in?" check.
1555                 $this->checkAsserts( $params );
1556
1557                 $module = $this->setupModule();
1558                 $this->mModule = $module;
1559
1560                 if ( !$this->mInternalMode ) {
1561                         $this->setRequestExpectations( $module );
1562                 }
1563
1564                 $this->checkExecutePermissions( $module );
1565
1566                 if ( !$this->checkMaxLag( $module, $params ) ) {
1567                         return;
1568                 }
1569
1570                 if ( !$this->checkConditionalRequestHeaders( $module ) ) {
1571                         return;
1572                 }
1573
1574                 if ( !$this->mInternalMode ) {
1575                         $this->setupExternalResponse( $module, $params );
1576                 }
1577
1578                 // Execute
1579                 $module->execute();
1580                 Hooks::run( 'APIAfterExecute', [ &$module ] );
1581
1582                 $this->reportUnusedParams();
1583
1584                 if ( !$this->mInternalMode ) {
1585                         // append Debug information
1586                         MWDebug::appendDebugInfoToApiResult( $this->getContext(), $this->getResult() );
1587
1588                         // Print result data
1589                         $this->printResult();
1590                 }
1591         }
1592
1593         /**
1594          * Set database connection, query, and write expectations given this module request
1595          * @param ApiBase $module
1596          */
1597         protected function setRequestExpectations( ApiBase $module ) {
1598                 $limits = $this->getConfig()->get( 'TrxProfilerLimits' );
1599                 $trxProfiler = Profiler::instance()->getTransactionProfiler();
1600                 $trxProfiler->setLogger( LoggerFactory::getInstance( 'DBPerformance' ) );
1601                 if ( $this->getRequest()->hasSafeMethod() ) {
1602                         $trxProfiler->setExpectations( $limits['GET'], __METHOD__ );
1603                 } elseif ( $this->getRequest()->wasPosted() && !$module->isWriteMode() ) {
1604                         $trxProfiler->setExpectations( $limits['POST-nonwrite'], __METHOD__ );
1605                         $this->getRequest()->markAsSafeRequest();
1606                 } else {
1607                         $trxProfiler->setExpectations( $limits['POST'], __METHOD__ );
1608                 }
1609         }
1610
1611         /**
1612          * Log the preceding request
1613          * @param float $time Time in seconds
1614          * @param Exception|null $e Exception caught while processing the request
1615          */
1616         protected function logRequest( $time, $e = null ) {
1617                 $request = $this->getRequest();
1618                 $logCtx = [
1619                         'ts' => time(),
1620                         'ip' => $request->getIP(),
1621                         'userAgent' => $this->getUserAgent(),
1622                         'wiki' => wfWikiID(),
1623                         'timeSpentBackend' => (int)round( $time * 1000 ),
1624                         'hadError' => $e !== null,
1625                         'errorCodes' => [],
1626                         'params' => [],
1627                 ];
1628
1629                 if ( $e ) {
1630                         foreach ( $this->errorMessagesFromException( $e ) as $msg ) {
1631                                 $logCtx['errorCodes'][] = $msg->getApiCode();
1632                         }
1633                 }
1634
1635                 // Construct space separated message for 'api' log channel
1636                 $msg = "API {$request->getMethod()} " .
1637                         wfUrlencode( str_replace( ' ', '_', $this->getUser()->getName() ) ) .
1638                         " {$logCtx['ip']} " .
1639                         "T={$logCtx['timeSpentBackend']}ms";
1640
1641                 $sensitive = array_flip( $this->getSensitiveParams() );
1642                 foreach ( $this->getParamsUsed() as $name ) {
1643                         $value = $request->getVal( $name );
1644                         if ( $value === null ) {
1645                                 continue;
1646                         }
1647
1648                         if ( isset( $sensitive[$name] ) ) {
1649                                 $value = '[redacted]';
1650                                 $encValue = '[redacted]';
1651                         } elseif ( strlen( $value ) > 256 ) {
1652                                 $value = substr( $value, 0, 256 );
1653                                 $encValue = $this->encodeRequestLogValue( $value ) . '[...]';
1654                         } else {
1655                                 $encValue = $this->encodeRequestLogValue( $value );
1656                         }
1657
1658                         $logCtx['params'][$name] = $value;
1659                         $msg .= " {$name}={$encValue}";
1660                 }
1661
1662                 wfDebugLog( 'api', $msg, 'private' );
1663                 // ApiAction channel is for structured data consumers
1664                 wfDebugLog( 'ApiAction', '', 'private', $logCtx );
1665         }
1666
1667         /**
1668          * Encode a value in a format suitable for a space-separated log line.
1669          * @param string $s
1670          * @return string
1671          */
1672         protected function encodeRequestLogValue( $s ) {
1673                 static $table;
1674                 if ( !$table ) {
1675                         $chars = ';@$!*(),/:';
1676                         $numChars = strlen( $chars );
1677                         for ( $i = 0; $i < $numChars; $i++ ) {
1678                                 $table[rawurlencode( $chars[$i] )] = $chars[$i];
1679                         }
1680                 }
1681
1682                 return strtr( rawurlencode( $s ), $table );
1683         }
1684
1685         /**
1686          * Get the request parameters used in the course of the preceding execute() request
1687          * @return array
1688          */
1689         protected function getParamsUsed() {
1690                 return array_keys( $this->mParamsUsed );
1691         }
1692
1693         /**
1694          * Mark parameters as used
1695          * @param string|string[] $params
1696          */
1697         public function markParamsUsed( $params ) {
1698                 $this->mParamsUsed += array_fill_keys( (array)$params, true );
1699         }
1700
1701         /**
1702          * Get the request parameters that should be considered sensitive
1703          * @since 1.29
1704          * @return array
1705          */
1706         protected function getSensitiveParams() {
1707                 return array_keys( $this->mParamsSensitive );
1708         }
1709
1710         /**
1711          * Mark parameters as sensitive
1712          * @since 1.29
1713          * @param string|string[] $params
1714          */
1715         public function markParamsSensitive( $params ) {
1716                 $this->mParamsSensitive += array_fill_keys( (array)$params, true );
1717         }
1718
1719         /**
1720          * Get a request value, and register the fact that it was used, for logging.
1721          * @param string $name
1722          * @param string|null $default
1723          * @return string|null
1724          */
1725         public function getVal( $name, $default = null ) {
1726                 $this->mParamsUsed[$name] = true;
1727
1728                 $ret = $this->getRequest()->getVal( $name );
1729                 if ( $ret === null ) {
1730                         if ( $this->getRequest()->getArray( $name ) !== null ) {
1731                                 // See T12262 for why we don't just implode( '|', ... ) the
1732                                 // array.
1733                                 $this->addWarning( [ 'apiwarn-unsupportedarray', $name ] );
1734                         }
1735                         $ret = $default;
1736                 }
1737                 return $ret;
1738         }
1739
1740         /**
1741          * Get a boolean request value, and register the fact that the parameter
1742          * was used, for logging.
1743          * @param string $name
1744          * @return bool
1745          */
1746         public function getCheck( $name ) {
1747                 return $this->getVal( $name, null ) !== null;
1748         }
1749
1750         /**
1751          * Get a request upload, and register the fact that it was used, for logging.
1752          *
1753          * @since 1.21
1754          * @param string $name Parameter name
1755          * @return WebRequestUpload
1756          */
1757         public function getUpload( $name ) {
1758                 $this->mParamsUsed[$name] = true;
1759
1760                 return $this->getRequest()->getUpload( $name );
1761         }
1762
1763         /**
1764          * Report unused parameters, so the client gets a hint in case it gave us parameters we don't know,
1765          * for example in case of spelling mistakes or a missing 'g' prefix for generators.
1766          */
1767         protected function reportUnusedParams() {
1768                 $paramsUsed = $this->getParamsUsed();
1769                 $allParams = $this->getRequest()->getValueNames();
1770
1771                 if ( !$this->mInternalMode ) {
1772                         // Printer has not yet executed; don't warn that its parameters are unused
1773                         $printerParams = $this->mPrinter->encodeParamName(
1774                                 array_keys( $this->mPrinter->getFinalParams() ?: [] )
1775                         );
1776                         $unusedParams = array_diff( $allParams, $paramsUsed, $printerParams );
1777                 } else {
1778                         $unusedParams = array_diff( $allParams, $paramsUsed );
1779                 }
1780
1781                 if ( count( $unusedParams ) ) {
1782                         $this->addWarning( [
1783                                 'apierror-unrecognizedparams',
1784                                 Message::listParam( array_map( 'wfEscapeWikiText', $unusedParams ), 'comma' ),
1785                                 count( $unusedParams )
1786                         ] );
1787                 }
1788         }
1789
1790         /**
1791          * Print results using the current printer
1792          *
1793          * @param int $httpCode HTTP status code, or 0 to not change
1794          */
1795         protected function printResult( $httpCode = 0 ) {
1796                 if ( $this->getConfig()->get( 'DebugAPI' ) !== false ) {
1797                         $this->addWarning( 'apiwarn-wgDebugAPI' );
1798                 }
1799
1800                 $printer = $this->mPrinter;
1801                 $printer->initPrinter( false );
1802                 if ( $httpCode ) {
1803                         $printer->setHttpStatus( $httpCode );
1804                 }
1805                 $printer->execute();
1806                 $printer->closePrinter();
1807         }
1808
1809         /**
1810          * @return bool
1811          */
1812         public function isReadMode() {
1813                 return false;
1814         }
1815
1816         /**
1817          * See ApiBase for description.
1818          *
1819          * @return array
1820          */
1821         public function getAllowedParams() {
1822                 return [
1823                         'action' => [
1824                                 ApiBase::PARAM_DFLT => 'help',
1825                                 ApiBase::PARAM_TYPE => 'submodule',
1826                         ],
1827                         'format' => [
1828                                 ApiBase::PARAM_DFLT => self::API_DEFAULT_FORMAT,
1829                                 ApiBase::PARAM_TYPE => 'submodule',
1830                         ],
1831                         'maxlag' => [
1832                                 ApiBase::PARAM_TYPE => 'integer'
1833                         ],
1834                         'smaxage' => [
1835                                 ApiBase::PARAM_TYPE => 'integer',
1836                                 ApiBase::PARAM_DFLT => 0
1837                         ],
1838                         'maxage' => [
1839                                 ApiBase::PARAM_TYPE => 'integer',
1840                                 ApiBase::PARAM_DFLT => 0
1841                         ],
1842                         'assert' => [
1843                                 ApiBase::PARAM_TYPE => [ 'user', 'bot' ]
1844                         ],
1845                         'assertuser' => [
1846                                 ApiBase::PARAM_TYPE => 'user',
1847                         ],
1848                         'requestid' => null,
1849                         'servedby' => false,
1850                         'curtimestamp' => false,
1851                         'responselanginfo' => false,
1852                         'origin' => null,
1853                         'uselang' => [
1854                                 ApiBase::PARAM_DFLT => self::API_DEFAULT_USELANG,
1855                         ],
1856                         'errorformat' => [
1857                                 ApiBase::PARAM_TYPE => [ 'plaintext', 'wikitext', 'html', 'raw', 'none', 'bc' ],
1858                                 ApiBase::PARAM_DFLT => 'bc',
1859                         ],
1860                         'errorlang' => [
1861                                 ApiBase::PARAM_DFLT => 'uselang',
1862                         ],
1863                         'errorsuselocal' => [
1864                                 ApiBase::PARAM_DFLT => false,
1865                         ],
1866                 ];
1867         }
1868
1869         /** @inheritDoc */
1870         protected function getExamplesMessages() {
1871                 return [
1872                         'action=help'
1873                                 => 'apihelp-help-example-main',
1874                         'action=help&recursivesubmodules=1'
1875                                 => 'apihelp-help-example-recursive',
1876                 ];
1877         }
1878
1879         public function modifyHelp( array &$help, array $options, array &$tocData ) {
1880                 // Wish PHP had an "array_insert_before". Instead, we have to manually
1881                 // reindex the array to get 'permissions' in the right place.
1882                 $oldHelp = $help;
1883                 $help = [];
1884                 foreach ( $oldHelp as $k => $v ) {
1885                         if ( $k === 'submodules' ) {
1886                                 $help['permissions'] = '';
1887                         }
1888                         $help[$k] = $v;
1889                 }
1890                 $help['datatypes'] = '';
1891                 $help['templatedparams'] = '';
1892                 $help['credits'] = '';
1893
1894                 // Fill 'permissions'
1895                 $help['permissions'] .= Html::openElement( 'div',
1896                         [ 'class' => 'apihelp-block apihelp-permissions' ] );
1897                 $m = $this->msg( 'api-help-permissions' );
1898                 if ( !$m->isDisabled() ) {
1899                         $help['permissions'] .= Html::rawElement( 'div', [ 'class' => 'apihelp-block-head' ],
1900                                 $m->numParams( count( self::$mRights ) )->parse()
1901                         );
1902                 }
1903                 $help['permissions'] .= Html::openElement( 'dl' );
1904                 foreach ( self::$mRights as $right => $rightMsg ) {
1905                         $help['permissions'] .= Html::element( 'dt', null, $right );
1906
1907                         $rightMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )->parse();
1908                         $help['permissions'] .= Html::rawElement( 'dd', null, $rightMsg );
1909
1910                         $groups = array_map( function ( $group ) {
1911                                 return $group == '*' ? 'all' : $group;
1912                         }, User::getGroupsWithPermission( $right ) );
1913
1914                         $help['permissions'] .= Html::rawElement( 'dd', null,
1915                                 $this->msg( 'api-help-permissions-granted-to' )
1916                                         ->numParams( count( $groups ) )
1917                                         ->params( Message::listParam( $groups ) )
1918                                         ->parse()
1919                         );
1920                 }
1921                 $help['permissions'] .= Html::closeElement( 'dl' );
1922                 $help['permissions'] .= Html::closeElement( 'div' );
1923
1924                 // Fill 'datatypes', 'templatedparams', and 'credits', if applicable
1925                 if ( empty( $options['nolead'] ) ) {
1926                         $level = $options['headerlevel'];
1927                         $tocnumber = &$options['tocnumber'];
1928
1929                         $header = $this->msg( 'api-help-datatypes-header' )->parse();
1930
1931                         $id = Sanitizer::escapeIdForAttribute( 'main/datatypes', Sanitizer::ID_PRIMARY );
1932                         $idFallback = Sanitizer::escapeIdForAttribute( 'main/datatypes', Sanitizer::ID_FALLBACK );
1933                         $headline = Linker::makeHeadline( min( 6, $level ),
1934                                 ' class="apihelp-header">',
1935                                 $id,
1936                                 $header,
1937                                 '',
1938                                 $idFallback
1939                         );
1940                         // Ensure we have a sane anchor
1941                         if ( $id !== 'main/datatypes' && $idFallback !== 'main/datatypes' ) {
1942                                 $headline = '<div id="main/datatypes"></div>' . $headline;
1943                         }
1944                         $help['datatypes'] .= $headline;
1945                         $help['datatypes'] .= $this->msg( 'api-help-datatypes' )->parseAsBlock();
1946                         if ( !isset( $tocData['main/datatypes'] ) ) {
1947                                 $tocnumber[$level]++;
1948                                 $tocData['main/datatypes'] = [
1949                                         'toclevel' => count( $tocnumber ),
1950                                         'level' => $level,
1951                                         'anchor' => 'main/datatypes',
1952                                         'line' => $header,
1953                                         'number' => implode( '.', $tocnumber ),
1954                                         'index' => false,
1955                                 ];
1956                         }
1957
1958                         $header = $this->msg( 'api-help-templatedparams-header' )->parse();
1959
1960                         $id = Sanitizer::escapeIdForAttribute( 'main/templatedparams', Sanitizer::ID_PRIMARY );
1961                         $idFallback = Sanitizer::escapeIdForAttribute( 'main/templatedparams', Sanitizer::ID_FALLBACK );
1962                         $headline = Linker::makeHeadline( min( 6, $level ),
1963                                 ' class="apihelp-header">',
1964                                 $id,
1965                                 $header,
1966                                 '',
1967                                 $idFallback
1968                         );
1969                         // Ensure we have a sane anchor
1970                         if ( $id !== 'main/templatedparams' && $idFallback !== 'main/templatedparams' ) {
1971                                 $headline = '<div id="main/templatedparams"></div>' . $headline;
1972                         }
1973                         $help['templatedparams'] .= $headline;
1974                         $help['templatedparams'] .= $this->msg( 'api-help-templatedparams' )->parseAsBlock();
1975                         if ( !isset( $tocData['main/templatedparams'] ) ) {
1976                                 $tocnumber[$level]++;
1977                                 $tocData['main/templatedparams'] = [
1978                                         'toclevel' => count( $tocnumber ),
1979                                         'level' => $level,
1980                                         'anchor' => 'main/templatedparams',
1981                                         'line' => $header,
1982                                         'number' => implode( '.', $tocnumber ),
1983                                         'index' => false,
1984                                 ];
1985                         }
1986
1987                         $header = $this->msg( 'api-credits-header' )->parse();
1988                         $id = Sanitizer::escapeIdForAttribute( 'main/credits', Sanitizer::ID_PRIMARY );
1989                         $idFallback = Sanitizer::escapeIdForAttribute( 'main/credits', Sanitizer::ID_FALLBACK );
1990                         $headline = Linker::makeHeadline( min( 6, $level ),
1991                                 ' class="apihelp-header">',
1992                                 $id,
1993                                 $header,
1994                                 '',
1995                                 $idFallback
1996                         );
1997                         // Ensure we have a sane anchor
1998                         if ( $id !== 'main/credits' && $idFallback !== 'main/credits' ) {
1999                                 $headline = '<div id="main/credits"></div>' . $headline;
2000                         }
2001                         $help['credits'] .= $headline;
2002                         $help['credits'] .= $this->msg( 'api-credits' )->useDatabase( false )->parseAsBlock();
2003                         if ( !isset( $tocData['main/credits'] ) ) {
2004                                 $tocnumber[$level]++;
2005                                 $tocData['main/credits'] = [
2006                                         'toclevel' => count( $tocnumber ),
2007                                         'level' => $level,
2008                                         'anchor' => 'main/credits',
2009                                         'line' => $header,
2010                                         'number' => implode( '.', $tocnumber ),
2011                                         'index' => false,
2012                                 ];
2013                         }
2014                 }
2015         }
2016
2017         private $mCanApiHighLimits = null;
2018
2019         /**
2020          * Check whether the current user is allowed to use high limits
2021          * @return bool
2022          */
2023         public function canApiHighLimits() {
2024                 if ( !isset( $this->mCanApiHighLimits ) ) {
2025                         $this->mCanApiHighLimits = $this->getUser()->isAllowed( 'apihighlimits' );
2026                 }
2027
2028                 return $this->mCanApiHighLimits;
2029         }
2030
2031         /**
2032          * Overrides to return this instance's module manager.
2033          * @return ApiModuleManager
2034          */
2035         public function getModuleManager() {
2036                 return $this->mModuleMgr;
2037         }
2038
2039         /**
2040          * Fetches the user agent used for this request
2041          *
2042          * The value will be the combination of the 'Api-User-Agent' header (if
2043          * any) and the standard User-Agent header (if any).
2044          *
2045          * @return string
2046          */
2047         public function getUserAgent() {
2048                 return trim(
2049                         $this->getRequest()->getHeader( 'Api-user-agent' ) . ' ' .
2050                         $this->getRequest()->getHeader( 'User-agent' )
2051                 );
2052         }
2053 }
2054
2055 /**
2056  * For really cool vim folding this needs to be at the end:
2057  * vim: foldmarker=@{,@} foldmethod=marker
2058  */