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, $mCdnMaxAge;
 152         /** @var ApiBase */
 153         private $mModule;
 154
 155         private $mCacheMode = 'private';
 156         /** @var array */
 157         private $mCacheControl = [];
 158         private $mParamsUsed = [];
 159         private $mParamsSensitive = [];
 160
 161         /** @var bool|null Cached return value from self::lacksSameOriginSecurity() */
 162         private $lacksSameOriginSecurity = null;
 163
 164         /**
 165          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 166          *
 167          * @param IContextSource|WebRequest|null $context If this is an instance of
 168          *    FauxRequest, errors are thrown and no printing occurs
 169          * @param bool $enableWrite Should be set to true if the api may modify data
 170          * @suppress PhanUndeclaredMethod
 171          */
 172         public function __construct( $context = null, $enableWrite = false ) {
 173                 if ( $context === null ) {
 174                         $context = RequestContext::getMain();
 175                 } elseif ( $context instanceof WebRequest ) {
 176                         // BC for pre-1.19
 177                         $request = $context;
 178                         $context = RequestContext::getMain();
 179                 }
 180                 // We set a derivative context so we can change stuff later
 181                 $this->setContext( new DerivativeContext( $context ) );
 182
 183                 if ( isset( $request ) ) {
 184                         $this->getContext()->setRequest( $request );
 185                 } else {
 186                         $request = $this->getRequest();
 187                 }
 188
 189                 $this->mInternalMode = ( $request instanceof FauxRequest );
 190
 191                 // Special handling for the main module: $parent === $this
 192                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 193
 194                 $config = $this->getConfig();
 195
 196                 if ( !$this->mInternalMode ) {
 197                         // Log if a request with a non-whitelisted Origin header is seen
 198                         // with session cookies.
 199                         $originHeader = $request->getHeader( 'Origin' );
 200                         if ( $originHeader === false ) {
 201                                 $origins = [];
 202                         } else {
 203                                 $originHeader = trim( $originHeader );
 204                                 $origins = preg_split( '/\s+/', $originHeader );
 205                         }
 206                         $sessionCookies = array_intersect(
 207                                 array_keys( $_COOKIE ),
 208                                 MediaWiki\Session\SessionManager::singleton()->getVaryCookies()
 209                         );
 210                         if ( $origins && $sessionCookies && (
 211                                 count( $origins ) !== 1 || !self::matchOrigin(
 212                                         $origins[0],
 213                                         $config->get( 'CrossSiteAJAXdomains' ),
 214                                         $config->get( 'CrossSiteAJAXdomainExceptions' )
 215                                 )
 216                         ) ) {
 217                                 LoggerFactory::getInstance( 'cors' )->warning(
 218                                         'Non-whitelisted CORS request with session cookies', [
 219                                                 'origin' => $originHeader,
 220                                                 'cookies' => $sessionCookies,
 221                                                 'ip' => $request->getIP(),
 222                                                 'userAgent' => $this->getUserAgent(),
 223                                                 'wiki' => WikiMap::getCurrentWikiDbDomain()->getId(),
 224                                         ]
 225                                 );
 226                         }
 227
 228                         // If we're in a mode that breaks the same-origin policy, strip
 229                         // user credentials for security.
 230                         if ( $this->lacksSameOriginSecurity() ) {
 231                                 global $wgUser;
 232                                 wfDebug( "API: stripping user credentials when the same-origin policy is not applied\n" );
 233                                 $wgUser = new User();
 234                                 $this->getContext()->setUser( $wgUser );
 235                                 $request->response()->header( 'MediaWiki-Login-Suppressed: true' );
 236                         }
 237                 }
 238
 239                 $this->mResult = new ApiResult( $this->getConfig()->get( 'APIMaxResultSize' ) );
 240
 241                 // Setup uselang. This doesn't use $this->getParameter()
 242                 // because we're not ready to handle errors yet.
 243                 // Optimisation: Avoid slow getVal(), this isn't user-generated content.
 244                 $uselang = $request->getRawVal( 'uselang', self::API_DEFAULT_USELANG );
 245                 if ( $uselang === 'user' ) {
 246                         // Assume the parent context is going to return the user language
 247                         // for uselang=user (see T85635).
 248                 } else {
 249                         if ( $uselang === 'content' ) {
 250                                 $uselang = MediaWikiServices::getInstance()->getContentLanguage()->getCode();
 251                         }
 252                         $code = RequestContext::sanitizeLangCode( $uselang );
 253                         $this->getContext()->setLanguage( $code );
 254                         if ( !$this->mInternalMode ) {
 255                                 global $wgLang;
 256                                 $wgLang = $this->getContext()->getLanguage();
 257                                 RequestContext::getMain()->setLanguage( $wgLang );
 258                         }
 259                 }
 260
 261                 // Set up the error formatter. This doesn't use $this->getParameter()
 262                 // because we're not ready to handle errors yet.
 263                 // Optimisation: Avoid slow getVal(), this isn't user-generated content.
 264                 $errorFormat = $request->getRawVal( 'errorformat', 'bc' );
 265                 $errorLangCode = $request->getRawVal( 'errorlang', 'uselang' );
 266                 $errorsUseDB = $request->getCheck( 'errorsuselocal' );
 267                 if ( in_array( $errorFormat, [ 'plaintext', 'wikitext', 'html', 'raw', 'none' ], true ) ) {
 268                         if ( $errorLangCode === 'uselang' ) {
 269                                 $errorLang = $this->getLanguage();
 270                         } elseif ( $errorLangCode === 'content' ) {
 271                                 $errorLang = MediaWikiServices::getInstance()->getContentLanguage();
 272                         } else {
 273                                 $errorLangCode = RequestContext::sanitizeLangCode( $errorLangCode );
 274                                 $errorLang = Language::factory( $errorLangCode );
 275                         }
 276                         $this->mErrorFormatter = new ApiErrorFormatter(
 277                                 $this->mResult, $errorLang, $errorFormat, $errorsUseDB
 278                         );
 279                 } else {
 280                         $this->mErrorFormatter = new ApiErrorFormatter_BackCompat( $this->mResult );
 281                 }
 282                 $this->mResult->setErrorFormatter( $this->getErrorFormatter() );
 283
 284                 $this->mModuleMgr = new ApiModuleManager( $this );
 285                 $this->mModuleMgr->addModules( self::$Modules, 'action' );
 286                 $this->mModuleMgr->addModules( $config->get( 'APIModules' ), 'action' );
 287                 $this->mModuleMgr->addModules( self::$Formats, 'format' );
 288                 $this->mModuleMgr->addModules( $config->get( 'APIFormatModules' ), 'format' );
 289
 290                 Hooks::run( 'ApiMain::moduleManager', [ $this->mModuleMgr ] );
 291
 292                 $this->mContinuationManager = null;
 293                 $this->mEnableWrite = $enableWrite;
 294
 295                 $this->mCdnMaxAge = -1; // flag for executeActionWithErrorHandling()
 296                 $this->mCommit = false;
 297         }
 298
 299         /**
 300          * Return true if the API was started by other PHP code using FauxRequest
 301          * @return bool
 302          */
 303         public function isInternalMode() {
 304                 return $this->mInternalMode;
 305         }
 306
 307         /**
 308          * Get the ApiResult object associated with current request
 309          *
 310          * @return ApiResult
 311          */
 312         public function getResult() {
 313                 return $this->mResult;
 314         }
 315
 316         /**
 317          * Get the security flag for the current request
 318          * @return bool
 319          */
 320         public function lacksSameOriginSecurity() {
 321                 if ( $this->lacksSameOriginSecurity !== null ) {
 322                         return $this->lacksSameOriginSecurity;
 323                 }
 324
 325                 $request = $this->getRequest();
 326
 327                 // JSONP mode
 328                 if ( $request->getCheck( 'callback' ) ) {
 329                         $this->lacksSameOriginSecurity = true;
 330                         return true;
 331                 }
 332
 333                 // Anonymous CORS
 334                 if ( $request->getVal( 'origin' ) === '*' ) {
 335                         $this->lacksSameOriginSecurity = true;
 336                         return true;
 337                 }
 338
 339                 // Header to be used from XMLHTTPRequest when the request might
 340                 // otherwise be used for XSS.
 341                 if ( $request->getHeader( 'Treat-as-Untrusted' ) !== false ) {
 342                         $this->lacksSameOriginSecurity = true;
 343                         return true;
 344                 }
 345
 346                 // Allow extensions to override.
 347                 $this->lacksSameOriginSecurity = !Hooks::run( 'RequestHasSameOriginSecurity', [ $request ] );
 348                 return $this->lacksSameOriginSecurity;
 349         }
 350
 351         /**
 352          * Get the ApiErrorFormatter object associated with current request
 353          * @return ApiErrorFormatter
 354          */
 355         public function getErrorFormatter() {
 356                 return $this->mErrorFormatter;
 357         }
 358
 359         /**
 360          * Get the continuation manager
 361          * @return ApiContinuationManager|null
 362          */
 363         public function getContinuationManager() {
 364                 return $this->mContinuationManager;
 365         }
 366
 367         /**
 368          * Set the continuation manager
 369          * @param ApiContinuationManager|null $manager
 370          */
 371         public function setContinuationManager( ApiContinuationManager $manager = null ) {
 372                 if ( $manager !== null && $this->mContinuationManager !== null ) {
 373                         throw new UnexpectedValueException(
 374                                 __METHOD__ . ': tried to set manager from ' . $manager->getSource() .
 375                                 ' when a manager is already set from ' . $this->mContinuationManager->getSource()
 376                         );
 377                 }
 378                 $this->mContinuationManager = $manager;
 379         }
 380
 381         /**
 382          * Get the API module object. Only works after executeAction()
 383          *
 384          * @return ApiBase
 385          */
 386         public function getModule() {
 387                 return $this->mModule;
 388         }
 389
 390         /**
 391          * Get the result formatter object. Only works after setupExecuteAction()
 392          *
 393          * @return ApiFormatBase
 394          */
 395         public function getPrinter() {
 396                 return $this->mPrinter;
 397         }
 398
 399         /**
 400          * Set how long the response should be cached.
 401          *
 402          * @param int $maxage
 403          */
 404         public function setCacheMaxAge( $maxage ) {
 405                 $this->setCacheControl( [
 406                         'max-age' => $maxage,
 407                         's-maxage' => $maxage
 408                 ] );
 409         }
 410
 411         /**
 412          * Set the type of caching headers which will be sent.
 413          *
 414          * @param string $mode One of:
 415          *    - 'public':     Cache this object in public caches, if the maxage or smaxage
 416          *         parameter is set, or if setCacheMaxAge() was called. If a maximum age is
 417          *         not provided by any of these means, the object will be private.
 418          *    - 'private':    Cache this object only in private client-side caches.
 419          *    - 'anon-public-user-private': Make this object cacheable for logged-out
 420          *         users, but private for logged-in users. IMPORTANT: If this is set, it must be
 421          *         set consistently for a given URL, it cannot be set differently depending on
 422          *         things like the contents of the database, or whether the user is logged in.
 423          *
 424          *  If the wiki does not allow anonymous users to read it, the mode set here
 425          *  will be ignored, and private caching headers will always be sent. In other words,
 426          *  the "public" mode is equivalent to saying that the data sent is as public as a page
 427          *  view.
 428          *
 429          *  For user-dependent data, the private mode should generally be used. The
 430          *  anon-public-user-private mode should only be used where there is a particularly
 431          *  good performance reason for caching the anonymous response, but where the
 432          *  response to logged-in users may differ, or may contain private data.
 433          *
 434          *  If this function is never called, then the default will be the private mode.
 435          */
 436         public function setCacheMode( $mode ) {
 437                 if ( !in_array( $mode, [ 'private', 'public', 'anon-public-user-private' ] ) ) {
 438                         wfDebug( __METHOD__ . ": unrecognised cache mode \"$mode\"\n" );
 439
 440                         // Ignore for forwards-compatibility
 441                         return;
 442                 }
 443
 444                 if ( !User::isEveryoneAllowed( 'read' ) ) {
 445                         // Private wiki, only private headers
 446                         if ( $mode !== 'private' ) {
 447                                 wfDebug( __METHOD__ . ": ignoring request for $mode cache mode, private wiki\n" );
 448
 449                                 return;
 450                         }
 451                 }
 452
 453                 if ( $mode === 'public' && $this->getParameter( 'uselang' ) === 'user' ) {
 454                         // User language is used for i18n, so we don't want to publicly
 455                         // cache. Anons are ok, because if they have non-default language
 456                         // then there's an appropriate Vary header set by whatever set
 457                         // their non-default language.
 458                         wfDebug( __METHOD__ . ": downgrading cache mode 'public' to " .
 459                                 "'anon-public-user-private' due to uselang=user\n" );
 460                         $mode = 'anon-public-user-private';
 461                 }
 462
 463                 wfDebug( __METHOD__ . ": setting cache mode $mode\n" );
 464                 $this->mCacheMode = $mode;
 465         }
 466
 467         /**
 468          * Set directives (key/value pairs) for the Cache-Control header.
 469          * Boolean values will be formatted as such, by including or omitting
 470          * without an equals sign.
 471          *
 472          * Cache control values set here will only be used if the cache mode is not
 473          * private, see setCacheMode().
 474          *
 475          * @param array $directives
 476          */
 477         public function setCacheControl( $directives ) {
 478                 $this->mCacheControl = $directives + $this->mCacheControl;
 479         }
 480
 481         /**
 482          * Create an instance of an output formatter by its name
 483          *
 484          * @param string $format
 485          *
 486          * @return ApiFormatBase
 487          */
 488         public function createPrinterByName( $format ) {
 489                 $printer = $this->mModuleMgr->getModule( $format, 'format', /* $ignoreCache */ true );
 490                 if ( $printer === null ) {
 491                         $this->dieWithError(
 492                                 [ 'apierror-unknownformat', wfEscapeWikiText( $format ) ], 'unknown_format'
 493                         );
 494                 }
 495
 496                 return $printer;
 497         }
 498
 499         /**
 500          * Execute api request. Any errors will be handled if the API was called by the remote client.
 501          */
 502         public function execute() {
 503                 if ( $this->mInternalMode ) {
 504                         $this->executeAction();
 505                 } else {
 506                         $this->executeActionWithErrorHandling();
 507                 }
 508         }
 509
 510         /**
 511          * Execute an action, and in case of an error, erase whatever partial results
 512          * have been accumulated, and replace it with an error message and a help screen.
 513          */
 514         protected function executeActionWithErrorHandling() {
 515                 // Verify the CORS header before executing the action
 516                 if ( !$this->handleCORS() ) {
 517                         // handleCORS() has sent a 403, abort
 518                         return;
 519                 }
 520
 521                 // Exit here if the request method was OPTIONS
 522                 // (assume there will be a followup GET or POST)
 523                 if ( $this->getRequest()->getMethod() === 'OPTIONS' ) {
 524                         return;
 525                 }
 526
 527                 // In case an error occurs during data output,
 528                 // clear the output buffer and print just the error information
 529                 $obLevel = ob_get_level();
 530                 ob_start();
 531
 532                 $t = microtime( true );
 533                 $isError = false;
 534                 try {
 535                         $this->executeAction();
 536                         $runTime = microtime( true ) - $t;
 537                         $this->logRequest( $runTime );
 538                         MediaWikiServices::getInstance()->getStatsdDataFactory()->timing(
 539                                 'api.' . $this->mModule->getModuleName() . '.executeTiming', 1000 * $runTime
 540                         );
 541                 } catch ( Exception $e ) { // @todo Remove this block when HHVM is no longer supported
 542                         $this->handleException( $e );
 543                         $this->logRequest( microtime( true ) - $t, $e );
 544                         $isError = true;
 545                 } catch ( Throwable $e ) {
 546                         $this->handleException( $e );
 547                         $this->logRequest( microtime( true ) - $t, $e );
 548                         $isError = true;
 549                 }
 550
 551                 // Commit DBs and send any related cookies and headers
 552                 MediaWiki::preOutputCommit( $this->getContext() );
 553
 554                 // Send cache headers after any code which might generate an error, to
 555                 // avoid sending public cache headers for errors.
 556                 $this->sendCacheHeaders( $isError );
 557
 558                 // Executing the action might have already messed with the output
 559                 // buffers.
 560                 while ( ob_get_level() > $obLevel ) {
 561                         ob_end_flush();
 562                 }
 563         }
 564
 565         /**
 566          * Handle an exception as an API response
 567          *
 568          * @since 1.23
 569          * @param Exception|Throwable $e
 570          */
 571         protected function handleException( $e ) {
 572                 // T65145: Rollback any open database transactions
 573                 if ( !$e instanceof ApiUsageException ) {
 574                         // ApiUsageExceptions are intentional, so don't rollback if that's the case
 575                         MWExceptionHandler::rollbackMasterChangesAndLog( $e );
 576                 }
 577
 578                 // Allow extra cleanup and logging
 579                 Hooks::run( 'ApiMain::onException', [ $this, $e ] );
 580
 581                 // Handle any kind of exception by outputting properly formatted error message.
 582                 // If this fails, an unhandled exception should be thrown so that global error
 583                 // handler will process and log it.
 584
 585                 $errCodes = $this->substituteResultWithError( $e );
 586
 587                 // Error results should not be cached
 588                 $this->setCacheMode( 'private' );
 589
 590                 $response = $this->getRequest()->response();
 591                 $headerStr = 'MediaWiki-API-Error: ' . implode( ', ', $errCodes );
 592                 $response->header( $headerStr );
 593
 594                 // Reset and print just the error message
 595                 ob_clean();
 596
 597                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 598                 $this->createErrorPrinter();
 599
 600                 // Get desired HTTP code from an ApiUsageException. Don't use codes from other
 601                 // exception types, as they are unlikely to be intended as an HTTP code.
 602                 $httpCode = $e instanceof ApiUsageException ? $e->getCode() : 0;
 603
 604                 $failed = false;
 605                 try {
 606                         $this->printResult( $httpCode );
 607                 } catch ( ApiUsageException $ex ) {
 608                         // The error printer itself is failing. Try suppressing its request
 609                         // parameters and redo.
 610                         $failed = true;
 611                         $this->addWarning( 'apiwarn-errorprinterfailed' );
 612                         foreach ( $ex->getStatusValue()->getErrors() as $error ) {
 613                                 try {
 614                                         $this->mPrinter->addWarning( $error );
 615                                 } catch ( Exception $ex2 ) { // @todo Remove this block when HHVM is no longer supported
 616                                         // WTF?
 617                                         $this->addWarning( $error );
 618                                 } catch ( Throwable $ex2 ) {
 619                                         // WTF?
 620                                         $this->addWarning( $error );
 621                                 }
 622                         }
 623                 }
 624                 if ( $failed ) {
 625                         $this->mPrinter = null;
 626                         $this->createErrorPrinter();
 627                         $this->mPrinter->forceDefaultParams();
 628                         if ( $httpCode ) {
 629                                 $response->statusHeader( 200 ); // Reset in case the fallback doesn't want a non-200
 630                         }
 631                         $this->printResult( $httpCode );
 632                 }
 633         }
 634
 635         /**
 636          * Handle an exception from the ApiBeforeMain hook.
 637          *
 638          * This tries to print the exception as an API response, to be more
 639          * friendly to clients. If it fails, it will rethrow the exception.
 640          *
 641          * @since 1.23
 642          * @param Exception|Throwable $e
 643          * @throws Exception|Throwable
 644          */
 645         public static function handleApiBeforeMainException( $e ) {
 646                 ob_start();
 647
 648                 try {
 649                         $main = new self( RequestContext::getMain(), false );
 650                         $main->handleException( $e );
 651                         $main->logRequest( 0, $e );
 652                 } catch ( Exception $e2 ) { // @todo Remove this block when HHVM is no longer supported
 653                         // Nope, even that didn't work. Punt.
 654                         throw $e;
 655                 } catch ( Throwable $e2 ) {
 656                         // Nope, even that didn't work. Punt.
 657                         throw $e;
 658                 }
 659
 660                 // Reset cache headers
 661                 $main->sendCacheHeaders( true );
 662
 663                 ob_end_flush();
 664         }
 665
 666         /**
 667          * Check the &origin= query parameter against the Origin: HTTP header and respond appropriately.
 668          *
 669          * If no origin parameter is present, nothing happens.
 670          * If an origin parameter is present but doesn't match the Origin header, a 403 status code
 671          * is set and false is returned.
 672          * If the parameter and the header do match, the header is checked against $wgCrossSiteAJAXdomains
 673          * and $wgCrossSiteAJAXdomainExceptions, and if the origin qualifies, the appropriate CORS
 674          * headers are set.
 675          * https://www.w3.org/TR/cors/#resource-requests
 676          * https://www.w3.org/TR/cors/#resource-preflight-requests
 677          *
 678          * @return bool False if the caller should abort (403 case), true otherwise (all other cases)
 679          */
 680         protected function handleCORS() {
 681                 $originParam = $this->getParameter( 'origin' ); // defaults to null
 682                 if ( $originParam === null ) {
 683                         // No origin parameter, nothing to do
 684                         return true;
 685                 }
 686
 687                 $request = $this->getRequest();
 688                 $response = $request->response();
 689
 690                 $matchedOrigin = false;
 691                 $allowTiming = false;
 692                 $varyOrigin = true;
 693
 694                 if ( $originParam === '*' ) {
 695                         // Request for anonymous CORS
 696                         // Technically we should check for the presence of an Origin header
 697                         // and not process it as CORS if it's not set, but that would
 698                         // require us to vary on Origin for all 'origin=*' requests which
 699                         // we don't want to do.
 700                         $matchedOrigin = true;
 701                         $allowOrigin = '*';
 702                         $allowCredentials = 'false';
 703                         $varyOrigin = false; // No need to vary
 704                 } else {
 705                         // Non-anonymous CORS, check we allow the domain
 706
 707                         // Origin: header is a space-separated list of origins, check all of them
 708                         $originHeader = $request->getHeader( 'Origin' );
 709                         if ( $originHeader === false ) {
 710                                 $origins = [];
 711                         } else {
 712                                 $originHeader = trim( $originHeader );
 713                                 $origins = preg_split( '/\s+/', $originHeader );
 714                         }
 715
 716                         if ( !in_array( $originParam, $origins ) ) {
 717                                 // origin parameter set but incorrect
 718                                 // Send a 403 response
 719                                 $response->statusHeader( 403 );
 720                                 $response->header( 'Cache-Control: no-cache' );
 721                                 echo "'origin' parameter does not match Origin header\n";
 722
 723                                 return false;
 724                         }
 725
 726                         $config = $this->getConfig();
 727                         $matchedOrigin = count( $origins ) === 1 && self::matchOrigin(
 728                                 $originParam,
 729                                 $config->get( 'CrossSiteAJAXdomains' ),
 730                                 $config->get( 'CrossSiteAJAXdomainExceptions' )
 731                         );
 732
 733                         $allowOrigin = $originHeader;
 734                         $allowCredentials = 'true';
 735                         $allowTiming = $originHeader;
 736                 }
 737
 738                 if ( $matchedOrigin ) {
 739                         $requestedMethod = $request->getHeader( 'Access-Control-Request-Method' );
 740                         $preflight = $request->getMethod() === 'OPTIONS' && $requestedMethod !== false;
 741                         if ( $preflight ) {
 742                                 // This is a CORS preflight request
 743                                 if ( $requestedMethod !== 'POST' && $requestedMethod !== 'GET' ) {
 744                                         // If method is not a case-sensitive match, do not set any additional headers and terminate.
 745                                         $response->header( 'MediaWiki-CORS-Rejection: Unsupported method requested in preflight' );
 746                                         return true;
 747                                 }
 748                                 // We allow the actual request to send the following headers
 749                                 $requestedHeaders = $request->getHeader( 'Access-Control-Request-Headers' );
 750                                 if ( $requestedHeaders !== false ) {
 751                                         if ( !self::matchRequestedHeaders( $requestedHeaders ) ) {
 752                                                 $response->header( 'MediaWiki-CORS-Rejection: Unsupported header requested in preflight' );
 753                                                 return true;
 754                                         }
 755                                         $response->header( 'Access-Control-Allow-Headers: ' . $requestedHeaders );
 756                                 }
 757
 758                                 // We only allow the actual request to be GET or POST
 759                                 $response->header( 'Access-Control-Allow-Methods: POST, GET' );
 760                         } elseif ( $request->getMethod() !== 'POST' && $request->getMethod() !== 'GET' ) {
 761                                 // Unsupported non-preflight method, don't handle it as CORS
 762                                 $response->header(
 763                                         'MediaWiki-CORS-Rejection: Unsupported method for simple request or actual request'
 764                                 );
 765                                 return true;
 766                         }
 767
 768                         $response->header( "Access-Control-Allow-Origin: $allowOrigin" );
 769                         $response->header( "Access-Control-Allow-Credentials: $allowCredentials" );
 770                         // https://www.w3.org/TR/resource-timing/#timing-allow-origin
 771                         if ( $allowTiming !== false ) {
 772                                 $response->header( "Timing-Allow-Origin: $allowTiming" );
 773                         }
 774
 775                         if ( !$preflight ) {
 776                                 $response->header(
 777                                         'Access-Control-Expose-Headers: MediaWiki-API-Error, Retry-After, X-Database-Lag, '
 778                                         . 'MediaWiki-Login-Suppressed'
 779                                 );
 780                         }
 781                 } else {
 782                         $response->header( 'MediaWiki-CORS-Rejection: Origin mismatch' );
 783                 }
 784
 785                 if ( $varyOrigin ) {
 786                         $this->getOutput()->addVaryHeader( 'Origin' );
 787                 }
 788
 789                 return true;
 790         }
 791
 792         /**
 793          * Attempt to match an Origin header against a set of rules and a set of exceptions
 794          * @param string $value Origin header
 795          * @param array $rules Set of wildcard rules
 796          * @param array $exceptions Set of wildcard rules
 797          * @return bool True if $value matches a rule in $rules and doesn't match
 798          *    any rules in $exceptions, false otherwise
 799          */
 800         protected static function matchOrigin( $value, $rules, $exceptions ) {
 801                 foreach ( $rules as $rule ) {
 802                         if ( preg_match( self::wildcardToRegex( $rule ), $value ) ) {
 803                                 // Rule matches, check exceptions
 804                                 foreach ( $exceptions as $exc ) {
 805                                         if ( preg_match( self::wildcardToRegex( $exc ), $value ) ) {
 806                                                 return false;
 807                                         }
 808                                 }
 809
 810                                 return true;
 811                         }
 812                 }
 813
 814                 return false;
 815         }
 816
 817         /**
 818          * Attempt to validate the value of Access-Control-Request-Headers against a list
 819          * of headers that we allow the follow up request to send.
 820          *
 821          * @param string $requestedHeaders Comma separated list of HTTP headers
 822          * @return bool True if all requested headers are in the list of allowed headers
 823          */
 824         protected static function matchRequestedHeaders( $requestedHeaders ) {
 825                 if ( trim( $requestedHeaders ) === '' ) {
 826                         return true;
 827                 }
 828                 $requestedHeaders = explode( ',', $requestedHeaders );
 829                 $allowedAuthorHeaders = array_flip( [
 830                         /* simple headers (see spec) */
 831                         'accept',
 832                         'accept-language',
 833                         'content-language',
 834                         'content-type',
 835                         /* non-authorable headers in XHR, which are however requested by some UAs */
 836                         'accept-encoding',
 837                         'dnt',
 838                         'origin',
 839                         /* MediaWiki whitelist */
 840                         'user-agent',
 841                         'api-user-agent',
 842                 ] );
 843                 foreach ( $requestedHeaders as $rHeader ) {
 844                         $rHeader = strtolower( trim( $rHeader ) );
 845                         if ( !isset( $allowedAuthorHeaders[$rHeader] ) ) {
 846                                 LoggerFactory::getInstance( 'api-warning' )->warning(
 847                                         'CORS preflight failed on requested header: {header}', [
 848                                                 'header' => $rHeader
 849                                         ]
 850                                 );
 851                                 return false;
 852                         }
 853                 }
 854                 return true;
 855         }
 856
 857         /**
 858          * Helper function to convert wildcard string into a regex
 859          * '*' => '.*?'
 860          * '?' => '.'
 861          *
 862          * @param string $wildcard String with wildcards
 863          * @return string Regular expression
 864          */
 865         protected static function wildcardToRegex( $wildcard ) {
 866                 $wildcard = preg_quote( $wildcard, '/' );
 867                 $wildcard = str_replace(
 868                         [ '\*', '\?' ],
 869                         [ '.*?', '.' ],
 870                         $wildcard
 871                 );
 872
 873                 return "/^https?:\/\/$wildcard$/";
 874         }
 875
 876         /**
 877          * Send caching headers
 878          * @param bool $isError Whether an error response is being output
 879          * @since 1.26 added $isError parameter
 880          */
 881         protected function sendCacheHeaders( $isError ) {
 882                 $response = $this->getRequest()->response();
 883                 $out = $this->getOutput();
 884
 885                 $out->addVaryHeader( 'Treat-as-Untrusted' );
 886
 887                 $config = $this->getConfig();
 888
 889                 if ( $config->get( 'VaryOnXFP' ) ) {
 890                         $out->addVaryHeader( 'X-Forwarded-Proto' );
 891                 }
 892
 893                 if ( !$isError && $this->mModule &&
 894                         ( $this->getRequest()->getMethod() === 'GET' || $this->getRequest()->getMethod() === 'HEAD' )
 895                 ) {
 896                         $etag = $this->mModule->getConditionalRequestData( 'etag' );
 897                         if ( $etag !== null ) {
 898                                 $response->header( "ETag: $etag" );
 899                         }
 900                         $lastMod = $this->mModule->getConditionalRequestData( 'last-modified' );
 901                         if ( $lastMod !== null ) {
 902                                 $response->header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $lastMod ) );
 903                         }
 904                 }
 905
 906                 // The logic should be:
 907                 // $this->mCacheControl['max-age'] is set?
 908                 //    Use it, the module knows better than our guess.
 909                 // !$this->mModule || $this->mModule->isWriteMode(), and mCacheMode is private?
 910                 //    Use 0 because we can guess caching is probably the wrong thing to do.
 911                 // Use $this->getParameter( 'maxage' ), which already defaults to 0.
 912                 $maxage = 0;
 913                 if ( isset( $this->mCacheControl['max-age'] ) ) {
 914                         $maxage = $this->mCacheControl['max-age'];
 915                 } elseif ( ( $this->mModule && !$this->mModule->isWriteMode() ) ||
 916                         $this->mCacheMode !== 'private'
 917                 ) {
 918                         $maxage = $this->getParameter( 'maxage' );
 919                 }
 920                 $privateCache = 'private, must-revalidate, max-age=' . $maxage;
 921
 922                 if ( $this->mCacheMode == 'private' ) {
 923                         $response->header( "Cache-Control: $privateCache" );
 924                         return;
 925                 }
 926
 927                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 928                         $out->addVaryHeader( 'Cookie' );
 929                         $response->header( $out->getVaryHeader() );
 930                         if ( MediaWiki\Session\SessionManager::getGlobalSession()->isPersistent() ) {
 931                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 932                                 // Mark request private
 933                                 $response->header( "Cache-Control: $privateCache" );
 934
 935                                 return;
 936                         } // else anonymous, send public headers below
 937                 }
 938
 939                 // Send public headers
 940                 $response->header( $out->getVaryHeader() );
 941
 942                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 943                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 944                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 945                 }
 946                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 947                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 948                 }
 949
 950                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 951                         // Public cache not requested
 952                         // Sending a Vary header in this case is harmless, and protects us
 953                         // against conditional calls of setCacheMaxAge().
 954                         $response->header( "Cache-Control: $privateCache" );
 955
 956                         return;
 957                 }
 958
 959                 $this->mCacheControl['public'] = true;
 960
 961                 // Send an Expires header
 962                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 963                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 964                 $response->header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 965
 966                 // Construct the Cache-Control header
 967                 $ccHeader = '';
 968                 $separator = '';
 969                 foreach ( $this->mCacheControl as $name => $value ) {
 970                         if ( is_bool( $value ) ) {
 971                                 if ( $value ) {
 972                                         $ccHeader .= $separator . $name;
 973                                         $separator = ', ';
 974                                 }
 975                         } else {
 976                                 $ccHeader .= $separator . "$name=$value";
 977                                 $separator = ', ';
 978                         }
 979                 }
 980
 981                 $response->header( "Cache-Control: $ccHeader" );
 982         }
 983
 984         /**
 985          * Create the printer for error output
 986          */
 987         private function createErrorPrinter() {
 988                 if ( !isset( $this->mPrinter ) ) {
 989                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 990                         if ( !$this->mModuleMgr->isDefined( $value, 'format' ) ) {
 991                                 $value = self::API_DEFAULT_FORMAT;
 992                         }
 993                         $this->mPrinter = $this->createPrinterByName( $value );
 994                 }
 995
 996                 // Printer may not be able to handle errors. This is particularly
 997                 // likely if the module returns something for getCustomPrinter().
 998                 if ( !$this->mPrinter->canPrintErrors() ) {
 999                         $this->mPrinter = $this->createPrinterByName( self::API_DEFAULT_FORMAT );
1000                 }
1001         }
1002
1003         /**
1004          * Create an error message for the given exception.
1005          *
1006          * If an ApiUsageException, errors/warnings will be extracted from the
1007          * embedded StatusValue.
1008          *
1009          * Any other exception will be returned with a generic code and wrapper
1010          * text around the exception's (presumably English) message as a single
1011          * error (no warnings).
1012          *
1013          * @param Exception|Throwable $e
1014          * @param string $type 'error' or 'warning'
1015          * @return ApiMessage[]
1016          * @since 1.27
1017          */
1018         protected function errorMessagesFromException( $e, $type = 'error' ) {
1019                 $messages = [];
1020                 if ( $e instanceof ApiUsageException ) {
1021                         foreach ( $e->getStatusValue()->getErrorsByType( $type ) as $error ) {
1022                                 $messages[] = ApiMessage::create( $error );
1023                         }
1024                 } elseif ( $type !== 'error' ) {
1025                         // None of the rest have any messages for non-error types
1026                 } else {
1027                         // Something is seriously wrong
1028                         $config = $this->getConfig();
1029                         // TODO: Avoid embedding arbitrary class names in the error code.
1030                         $class = preg_replace( '#^Wikimedia\\\Rdbms\\\#', '', get_class( $e ) );
1031                         $code = 'internal_api_error_' . $class;
1032                         $data = [ 'errorclass' => get_class( $e ) ];
1033                         if ( $config->get( 'ShowExceptionDetails' ) ) {
1034                                 if ( $e instanceof ILocalizedException ) {
1035                                         $msg = $e->getMessageObject();
1036                                 } elseif ( $e instanceof MessageSpecifier ) {
1037                                         $msg = Message::newFromSpecifier( $e );
1038                                 } else {
1039                                         $msg = wfEscapeWikiText( $e->getMessage() );
1040                                 }
1041                                 $params = [ 'apierror-exceptioncaught', WebRequest::getRequestId(), $msg ];
1042                         } else {
1043                                 $params = [ 'apierror-exceptioncaughttype', WebRequest::getRequestId(), get_class( $e ) ];
1044                         }
1045
1046                         $messages[] = ApiMessage::create( $params, $code, $data );
1047                 }
1048                 return $messages;
1049         }
1050
1051         /**
1052          * Replace the result data with the information about an exception.
1053          * @param Exception|Throwable $e
1054          * @return string[] Error codes
1055          */
1056         protected function substituteResultWithError( $e ) {
1057                 $result = $this->getResult();
1058                 $formatter = $this->getErrorFormatter();
1059                 $config = $this->getConfig();
1060                 $errorCodes = [];
1061
1062                 // Remember existing warnings and errors across the reset
1063                 $errors = $result->getResultData( [ 'errors' ] );
1064                 $warnings = $result->getResultData( [ 'warnings' ] );
1065                 $result->reset();
1066                 if ( $warnings !== null ) {
1067                         $result->addValue( null, 'warnings', $warnings, ApiResult::NO_SIZE_CHECK );
1068                 }
1069                 if ( $errors !== null ) {
1070                         $result->addValue( null, 'errors', $errors, ApiResult::NO_SIZE_CHECK );
1071
1072                         // Collect the copied error codes for the return value
1073                         foreach ( $errors as $error ) {
1074                                 if ( isset( $error['code'] ) ) {
1075                                         $errorCodes[$error['code']] = true;
1076                                 }
1077                         }
1078                 }
1079
1080                 // Add errors from the exception
1081                 $modulePath = $e instanceof ApiUsageException ? $e->getModulePath() : null;
1082                 foreach ( $this->errorMessagesFromException( $e, 'error' ) as $msg ) {
1083                         if ( ApiErrorFormatter::isValidApiCode( $msg->getApiCode() ) ) {
1084                                 $errorCodes[$msg->getApiCode()] = true;
1085                         } else {
1086                                 LoggerFactory::getInstance( 'api-warning' )->error( 'Invalid API error code "{code}"', [
1087                                         'code' => $msg->getApiCode(),
1088                                         'exception' => $e,
1089                                 ] );
1090                                 $errorCodes['<invalid-code>'] = true;
1091                         }
1092                         $formatter->addError( $modulePath, $msg );
1093                 }
1094                 foreach ( $this->errorMessagesFromException( $e, 'warning' ) as $msg ) {
1095                         $formatter->addWarning( $modulePath, $msg );
1096                 }
1097
1098                 // Add additional data. Path depends on whether we're in BC mode or not.
1099                 // Data depends on the type of exception.
1100                 if ( $formatter instanceof ApiErrorFormatter_BackCompat ) {
1101                         $path = [ 'error' ];
1102                 } else {
1103                         $path = null;
1104                 }
1105                 if ( $e instanceof ApiUsageException ) {
1106                         $link = wfExpandUrl( wfScript( 'api' ) );
1107                         $result->addContentValue(
1108                                 $path,
1109                                 'docref',
1110                                 trim(
1111                                         $this->msg( 'api-usage-docref', $link )->inLanguage( $formatter->getLanguage() )->text()
1112                                         . ' '
1113                                         . $this->msg( 'api-usage-mailinglist-ref' )->inLanguage( $formatter->getLanguage() )->text()
1114                                 )
1115                         );
1116                 } elseif ( $config->get( 'ShowExceptionDetails' ) ) {
1117                         $result->addContentValue(
1118                                 $path,
1119                                 'trace',
1120                                 $this->msg( 'api-exception-trace',
1121                                         get_class( $e ),
1122                                         $e->getFile(),
1123                                         $e->getLine(),
1124                                         MWExceptionHandler::getRedactedTraceAsString( $e )
1125                                 )->inLanguage( $formatter->getLanguage() )->text()
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                                 $response->header( 'Retry-After: ' . max( (int)$maxLag, 5 ) );
1275                                 $response->header( 'X-Database-Lag: ' . (int)$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                                                 $config = $this->getConfig();
1368                                                 $lastMod = $module->getConditionalRequestData( 'last-modified' );
1369                                                 if ( $lastMod !== null ) {
1370                                                         // Mix in some MediaWiki modification times
1371                                                         $modifiedTimes = [
1372                                                                 'page' => $lastMod,
1373                                                                 'user' => $this->getUser()->getTouched(),
1374                                                                 'epoch' => $config->get( 'CacheEpoch' ),
1375                                                         ];
1376
1377                                                         if ( $config->get( 'UseCdn' ) ) {
1378                                                                 // T46570: the core page itself may not change, but resources might
1379                                                                 $modifiedTimes['sepoch'] = wfTimestamp(
1380                                                                         TS_MW, time() - $config->get( 'CdnMaxAge' )
1381                                                                 );
1382                                                         }
1383                                                         Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this->getOutput() ] );
1384                                                         $lastMod = max( $modifiedTimes );
1385                                                         $return304 = wfTimestamp( TS_MW, $lastMod ) <= $ts->getTimestamp( TS_MW );
1386                                                 }
1387                                         }
1388                                 } catch ( TimestampException $e ) {
1389                                         // Invalid timestamp, ignore it
1390                                 }
1391                         }
1392                 }
1393
1394                 if ( $return304 ) {
1395                         $this->getRequest()->response()->statusHeader( 304 );
1396
1397                         // Avoid outputting the compressed representation of a zero-length body
1398                         Wikimedia\suppressWarnings();
1399                         ini_set( 'zlib.output_compression', 0 );
1400                         Wikimedia\restoreWarnings();
1401                         wfClearOutputBuffers();
1402
1403                         return false;
1404                 }
1405
1406                 return true;
1407         }
1408
1409         /**
1410          * Check for sufficient permissions to execute
1411          * @param ApiBase $module An Api module
1412          */
1413         protected function checkExecutePermissions( $module ) {
1414                 $user = $this->getUser();
1415                 if ( $module->isReadMode() && !$this->getPermissionManager()->isEveryoneAllowed( 'read' ) &&
1416                         !$this->getPermissionManager()->userHasRight( $user, 'read' )
1417                 ) {
1418                         $this->dieWithError( 'apierror-readapidenied' );
1419                 }
1420
1421                 if ( $module->isWriteMode() ) {
1422                         if ( !$this->mEnableWrite ) {
1423                                 $this->dieWithError( 'apierror-noapiwrite' );
1424                         } elseif ( !$this->getPermissionManager()->userHasRight( $user, 'writeapi' ) ) {
1425                                 $this->dieWithError( 'apierror-writeapidenied' );
1426                         } elseif ( $this->getRequest()->getHeader( 'Promise-Non-Write-API-Action' ) ) {
1427                                 $this->dieWithError( 'apierror-promised-nonwrite-api' );
1428                         }
1429
1430                         $this->checkReadOnly( $module );
1431                 }
1432
1433                 // Allow extensions to stop execution for arbitrary reasons.
1434                 $message = 'hookaborted';
1435                 if ( !Hooks::run( 'ApiCheckCanExecute', [ $module, $user, &$message ] ) ) {
1436                         $this->dieWithError( $message );
1437                 }
1438         }
1439
1440         /**
1441          * Check if the DB is read-only for this user
1442          * @param ApiBase $module An Api module
1443          */
1444         protected function checkReadOnly( $module ) {
1445                 if ( wfReadOnly() ) {
1446                         $this->dieReadOnly();
1447                 }
1448
1449                 if ( $module->isWriteMode()
1450                         && $this->getUser()->isBot()
1451                         && MediaWikiServices::getInstance()->getDBLoadBalancer()->getServerCount() > 1
1452                 ) {
1453                         $this->checkBotReadOnly();
1454                 }
1455         }
1456
1457         /**
1458          * Check whether we are readonly for bots
1459          */
1460         private function checkBotReadOnly() {
1461                 // Figure out how many servers have passed the lag threshold
1462                 $numLagged = 0;
1463                 $lagLimit = $this->getConfig()->get( 'APIMaxLagThreshold' );
1464                 $laggedServers = [];
1465                 $loadBalancer = MediaWikiServices::getInstance()->getDBLoadBalancer();
1466                 foreach ( $loadBalancer->getLagTimes() as $serverIndex => $lag ) {
1467                         if ( $lag > $lagLimit ) {
1468                                 ++$numLagged;
1469                                 $laggedServers[] = $loadBalancer->getServerName( $serverIndex ) . " ({$lag}s)";
1470                         }
1471                 }
1472
1473                 // If a majority of replica DBs are too lagged then disallow writes
1474                 $replicaCount = $loadBalancer->getServerCount() - 1;
1475                 if ( $numLagged >= ceil( $replicaCount / 2 ) ) {
1476                         $laggedServers = implode( ', ', $laggedServers );
1477                         wfDebugLog(
1478                                 'api-readonly', // Deprecate this channel in favor of api-warning?
1479                                 "Api request failed as read only because the following DBs are lagged: $laggedServers"
1480                         );
1481                         LoggerFactory::getInstance( 'api-warning' )->warning(
1482                                 "Api request failed as read only because the following DBs are lagged: {laggeddbs}", [
1483                                         'laggeddbs' => $laggedServers,
1484                                 ]
1485                         );
1486
1487                         $this->dieWithError(
1488                                 'readonly_lag',
1489                                 'readonly',
1490                                 [ 'readonlyreason' => "Waiting for $numLagged lagged database(s)" ]
1491                         );
1492                 }
1493         }
1494
1495         /**
1496          * Check asserts of the user's rights
1497          * @param array $params
1498          */
1499         protected function checkAsserts( $params ) {
1500                 if ( isset( $params['assert'] ) ) {
1501                         $user = $this->getUser();
1502                         switch ( $params['assert'] ) {
1503                                 case 'user':
1504                                         if ( $user->isAnon() ) {
1505                                                 $this->dieWithError( 'apierror-assertuserfailed' );
1506                                         }
1507                                         break;
1508                                 case 'bot':
1509                                         if ( !$this->getPermissionManager()->userHasRight( $user, 'bot' ) ) {
1510                                                 $this->dieWithError( 'apierror-assertbotfailed' );
1511                                         }
1512                                         break;
1513                         }
1514                 }
1515                 if ( isset( $params['assertuser'] ) ) {
1516                         $assertUser = User::newFromName( $params['assertuser'], false );
1517                         if ( !$assertUser || !$this->getUser()->equals( $assertUser ) ) {
1518                                 $this->dieWithError(
1519                                         [ 'apierror-assertnameduserfailed', wfEscapeWikiText( $params['assertuser'] ) ]
1520                                 );
1521                         }
1522                 }
1523         }
1524
1525         /**
1526          * Check POST for external response and setup result printer
1527          * @param ApiBase $module An Api module
1528          * @param array $params An array with the request parameters
1529          */
1530         protected function setupExternalResponse( $module, $params ) {
1531                 $validMethods = [ 'GET', 'HEAD', 'POST', 'OPTIONS' ];
1532                 $request = $this->getRequest();
1533
1534                 if ( !in_array( $request->getMethod(), $validMethods ) ) {
1535                         $this->dieWithError( 'apierror-invalidmethod', null, null, 405 );
1536                 }
1537
1538                 if ( !$request->wasPosted() && $module->mustBePosted() ) {
1539                         // Module requires POST. GET request might still be allowed
1540                         // if $wgDebugApi is true, otherwise fail.
1541                         $this->dieWithErrorOrDebug( [ 'apierror-mustbeposted', $this->mAction ] );
1542                 }
1543
1544                 if ( $request->wasPosted() && !$request->getHeader( 'Content-Type' ) ) {
1545                         $this->addDeprecation(
1546                                 'apiwarn-deprecation-post-without-content-type', 'post-without-content-type'
1547                         );
1548                 }
1549
1550                 // See if custom printer is used
1551                 $this->mPrinter = $module->getCustomPrinter();
1552                 if ( is_null( $this->mPrinter ) ) {
1553                         // Create an appropriate printer
1554                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
1555                 }
1556
1557                 if ( $request->getProtocol() === 'http' && (
1558                         $request->getSession()->shouldForceHTTPS() ||
1559                         ( $this->getUser()->isLoggedIn() &&
1560                                 $this->getUser()->requiresHTTPS() )
1561                 ) ) {
1562                         $this->addDeprecation( 'apiwarn-deprecation-httpsexpected', 'https-expected' );
1563                 }
1564         }
1565
1566         /**
1567          * Execute the actual module, without any error handling
1568          */
1569         protected function executeAction() {
1570                 $params = $this->setupExecuteAction();
1571
1572                 // Check asserts early so e.g. errors in parsing a module's parameters due to being
1573                 // logged out don't override the client's intended "am I logged in?" check.
1574                 $this->checkAsserts( $params );
1575
1576                 $module = $this->setupModule();
1577                 $this->mModule = $module;
1578
1579                 if ( !$this->mInternalMode ) {
1580                         $this->setRequestExpectations( $module );
1581                 }
1582
1583                 $this->checkExecutePermissions( $module );
1584
1585                 if ( !$this->checkMaxLag( $module, $params ) ) {
1586                         return;
1587                 }
1588
1589                 if ( !$this->checkConditionalRequestHeaders( $module ) ) {
1590                         return;
1591                 }
1592
1593                 if ( !$this->mInternalMode ) {
1594                         $this->setupExternalResponse( $module, $params );
1595                 }
1596
1597                 $module->execute();
1598                 Hooks::run( 'APIAfterExecute', [ &$module ] );
1599
1600                 $this->reportUnusedParams();
1601
1602                 if ( !$this->mInternalMode ) {
1603                         MWDebug::appendDebugInfoToApiResult( $this->getContext(), $this->getResult() );
1604
1605                         $this->printResult();
1606                 }
1607         }
1608
1609         /**
1610          * Set database connection, query, and write expectations given this module request
1611          * @param ApiBase $module
1612          */
1613         protected function setRequestExpectations( ApiBase $module ) {
1614                 $limits = $this->getConfig()->get( 'TrxProfilerLimits' );
1615                 $trxProfiler = Profiler::instance()->getTransactionProfiler();
1616                 $trxProfiler->setLogger( LoggerFactory::getInstance( 'DBPerformance' ) );
1617                 if ( $this->getRequest()->hasSafeMethod() ) {
1618                         $trxProfiler->setExpectations( $limits['GET'], __METHOD__ );
1619                 } elseif ( $this->getRequest()->wasPosted() && !$module->isWriteMode() ) {
1620                         $trxProfiler->setExpectations( $limits['POST-nonwrite'], __METHOD__ );
1621                         $this->getRequest()->markAsSafeRequest();
1622                 } else {
1623                         $trxProfiler->setExpectations( $limits['POST'], __METHOD__ );
1624                 }
1625         }
1626
1627         /**
1628          * Log the preceding request
1629          * @param float $time Time in seconds
1630          * @param Exception|Throwable|null $e Exception caught while processing the request
1631          */
1632         protected function logRequest( $time, $e = null ) {
1633                 $request = $this->getRequest();
1634
1635                 $logCtx = [
1636                         // https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/event-schemas/+/master/jsonschema/mediawiki/api/request
1637                         '$schema' => '/mediawiki/api/request/0.0.1',
1638                         'meta' => [
1639                                 'request_id' => WebRequest::getRequestId(),
1640                                 'id' => UIDGenerator::newUUIDv4(),
1641                                 'dt' => wfTimestamp( TS_ISO_8601 ),
1642                                 'domain' => $this->getConfig()->get( 'ServerName' ),
1643                                 // If using the EventBus extension (as intended) with this log channel,
1644                                 // this stream name will map to a Kafka topic.
1645                                 'stream' => 'mediawiki.api-request'
1646                         ],
1647                         'http' => [
1648                                 'method' => $request->getMethod(),
1649                                 'client_ip' => $request->getIP()
1650                         ],
1651                         'database' => WikiMap::getCurrentWikiDbDomain()->getId(),
1652                         'backend_time_ms' => (int)round( $time * 1000 ),
1653                 ];
1654
1655                 // If set, these headers will be logged in http.request_headers.
1656                 $httpRequestHeadersToLog = [ 'accept-language', 'referer', 'user-agent' ];
1657                 foreach ( $httpRequestHeadersToLog as $header ) {
1658                         if ( $request->getHeader( $header ) ) {
1659                                 // Set the header in http.request_headers
1660                                 $logCtx['http']['request_headers'][$header] = $request->getHeader( $header );
1661                         }
1662                 }
1663
1664                 if ( $e ) {
1665                         $logCtx['api_error_codes'] = [];
1666                         foreach ( $this->errorMessagesFromException( $e ) as $msg ) {
1667                                 $logCtx['api_error_codes'][] = $msg->getApiCode();
1668                         }
1669                 }
1670
1671                 // Construct space separated message for 'api' log channel
1672                 $msg = "API {$request->getMethod()} " .
1673                         wfUrlencode( str_replace( ' ', '_', $this->getUser()->getName() ) ) .
1674                         " {$logCtx['http']['client_ip']} " .
1675                         "T={$logCtx['backend_time_ms']}ms";
1676
1677                 $sensitive = array_flip( $this->getSensitiveParams() );
1678                 foreach ( $this->getParamsUsed() as $name ) {
1679                         $value = $request->getVal( $name );
1680                         if ( $value === null ) {
1681                                 continue;
1682                         }
1683
1684                         if ( isset( $sensitive[$name] ) ) {
1685                                 $value = '[redacted]';
1686                                 $encValue = '[redacted]';
1687                         } elseif ( strlen( $value ) > 256 ) {
1688                                 $value = substr( $value, 0, 256 );
1689                                 $encValue = $this->encodeRequestLogValue( $value ) . '[...]';
1690                         } else {
1691                                 $encValue = $this->encodeRequestLogValue( $value );
1692                         }
1693
1694                         $logCtx['params'][$name] = $value;
1695                         $msg .= " {$name}={$encValue}";
1696                 }
1697
1698                 // Log an unstructured message to the api channel.
1699                 wfDebugLog( 'api', $msg, 'private' );
1700
1701                 // The api-request channel a structured data log channel.
1702                 wfDebugLog( 'api-request', '', 'private', $logCtx );
1703         }
1704
1705         /**
1706          * Encode a value in a format suitable for a space-separated log line.
1707          * @param string $s
1708          * @return string
1709          */
1710         protected function encodeRequestLogValue( $s ) {
1711                 static $table = [];
1712                 if ( !$table ) {
1713                         $chars = ';@$!*(),/:';
1714                         $numChars = strlen( $chars );
1715                         for ( $i = 0; $i < $numChars; $i++ ) {
1716                                 $table[rawurlencode( $chars[$i] )] = $chars[$i];
1717                         }
1718                 }
1719
1720                 return strtr( rawurlencode( $s ), $table );
1721         }
1722
1723         /**
1724          * Get the request parameters used in the course of the preceding execute() request
1725          * @return array
1726          */
1727         protected function getParamsUsed() {
1728                 return array_keys( $this->mParamsUsed );
1729         }
1730
1731         /**
1732          * Mark parameters as used
1733          * @param string|string[] $params
1734          */
1735         public function markParamsUsed( $params ) {
1736                 $this->mParamsUsed += array_fill_keys( (array)$params, true );
1737         }
1738
1739         /**
1740          * Get the request parameters that should be considered sensitive
1741          * @since 1.29
1742          * @return array
1743          */
1744         protected function getSensitiveParams() {
1745                 return array_keys( $this->mParamsSensitive );
1746         }
1747
1748         /**
1749          * Mark parameters as sensitive
1750          * @since 1.29
1751          * @param string|string[] $params
1752          */
1753         public function markParamsSensitive( $params ) {
1754                 $this->mParamsSensitive += array_fill_keys( (array)$params, true );
1755         }
1756
1757         /**
1758          * Get a request value, and register the fact that it was used, for logging.
1759          * @param string $name
1760          * @param string|null $default
1761          * @return string|null
1762          */
1763         public function getVal( $name, $default = null ) {
1764                 $this->mParamsUsed[$name] = true;
1765
1766                 $ret = $this->getRequest()->getVal( $name );
1767                 if ( $ret === null ) {
1768                         if ( $this->getRequest()->getArray( $name ) !== null ) {
1769                                 // See T12262 for why we don't just implode( '|', ... ) the
1770                                 // array.
1771                                 $this->addWarning( [ 'apiwarn-unsupportedarray', $name ] );
1772                         }
1773                         $ret = $default;
1774                 }
1775                 return $ret;
1776         }
1777
1778         /**
1779          * Get a boolean request value, and register the fact that the parameter
1780          * was used, for logging.
1781          * @param string $name
1782          * @return bool
1783          */
1784         public function getCheck( $name ) {
1785                 return $this->getVal( $name, null ) !== null;
1786         }
1787
1788         /**
1789          * Get a request upload, and register the fact that it was used, for logging.
1790          *
1791          * @since 1.21
1792          * @param string $name Parameter name
1793          * @return WebRequestUpload
1794          */
1795         public function getUpload( $name ) {
1796                 $this->mParamsUsed[$name] = true;
1797
1798                 return $this->getRequest()->getUpload( $name );
1799         }
1800
1801         /**
1802          * Report unused parameters, so the client gets a hint in case it gave us parameters we don't know,
1803          * for example in case of spelling mistakes or a missing 'g' prefix for generators.
1804          */
1805         protected function reportUnusedParams() {
1806                 $paramsUsed = $this->getParamsUsed();
1807                 $allParams = $this->getRequest()->getValueNames();
1808
1809                 if ( !$this->mInternalMode ) {
1810                         // Printer has not yet executed; don't warn that its parameters are unused
1811                         $printerParams = $this->mPrinter->encodeParamName(
1812                                 array_keys( $this->mPrinter->getFinalParams() ?: [] )
1813                         );
1814                         $unusedParams = array_diff( $allParams, $paramsUsed, $printerParams );
1815                 } else {
1816                         $unusedParams = array_diff( $allParams, $paramsUsed );
1817                 }
1818
1819                 if ( count( $unusedParams ) ) {
1820                         $this->addWarning( [
1821                                 'apierror-unrecognizedparams',
1822                                 Message::listParam( array_map( 'wfEscapeWikiText', $unusedParams ), 'comma' ),
1823                                 count( $unusedParams )
1824                         ] );
1825                 }
1826         }
1827
1828         /**
1829          * Print results using the current printer
1830          *
1831          * @param int $httpCode HTTP status code, or 0 to not change
1832          */
1833         protected function printResult( $httpCode = 0 ) {
1834                 if ( $this->getConfig()->get( 'DebugAPI' ) !== false ) {
1835                         $this->addWarning( 'apiwarn-wgdebugapi' );
1836                 }
1837
1838                 $printer = $this->mPrinter;
1839                 $printer->initPrinter( false );
1840                 if ( $httpCode ) {
1841                         $printer->setHttpStatus( $httpCode );
1842                 }
1843                 $printer->execute();
1844                 $printer->closePrinter();
1845         }
1846
1847         /**
1848          * @return bool
1849          */
1850         public function isReadMode() {
1851                 return false;
1852         }
1853
1854         /**
1855          * See ApiBase for description.
1856          *
1857          * @return array
1858          */
1859         public function getAllowedParams() {
1860                 return [
1861                         'action' => [
1862                                 ApiBase::PARAM_DFLT => 'help',
1863                                 ApiBase::PARAM_TYPE => 'submodule',
1864                         ],
1865                         'format' => [
1866                                 ApiBase::PARAM_DFLT => self::API_DEFAULT_FORMAT,
1867                                 ApiBase::PARAM_TYPE => 'submodule',
1868                         ],
1869                         'maxlag' => [
1870                                 ApiBase::PARAM_TYPE => 'integer'
1871                         ],
1872                         'smaxage' => [
1873                                 ApiBase::PARAM_TYPE => 'integer',
1874                                 ApiBase::PARAM_DFLT => 0
1875                         ],
1876                         'maxage' => [
1877                                 ApiBase::PARAM_TYPE => 'integer',
1878                                 ApiBase::PARAM_DFLT => 0
1879                         ],
1880                         'assert' => [
1881                                 ApiBase::PARAM_TYPE => [ 'user', 'bot' ]
1882                         ],
1883                         'assertuser' => [
1884                                 ApiBase::PARAM_TYPE => 'user',
1885                         ],
1886                         'requestid' => null,
1887                         'servedby' => false,
1888                         'curtimestamp' => false,
1889                         'responselanginfo' => false,
1890                         'origin' => null,
1891                         'uselang' => [
1892                                 ApiBase::PARAM_DFLT => self::API_DEFAULT_USELANG,
1893                         ],
1894                         'errorformat' => [
1895                                 ApiBase::PARAM_TYPE => [ 'plaintext', 'wikitext', 'html', 'raw', 'none', 'bc' ],
1896                                 ApiBase::PARAM_DFLT => 'bc',
1897                         ],
1898                         'errorlang' => [
1899                                 ApiBase::PARAM_DFLT => 'uselang',
1900                         ],
1901                         'errorsuselocal' => [
1902                                 ApiBase::PARAM_DFLT => false,
1903                         ],
1904                 ];
1905         }
1906
1907         /** @inheritDoc */
1908         protected function getExamplesMessages() {
1909                 return [
1910                         'action=help'
1911                                 => 'apihelp-help-example-main',
1912                         'action=help&recursivesubmodules=1'
1913                                 => 'apihelp-help-example-recursive',
1914                 ];
1915         }
1916
1917         /**
1918          * @inheritDoc
1919          * @phan-param array{nolead?:bool,headerlevel?:int,tocnumber?:int[]} $options
1920          */
1921         public function modifyHelp( array &$help, array $options, array &$tocData ) {
1922                 // Wish PHP had an "array_insert_before". Instead, we have to manually
1923                 // reindex the array to get 'permissions' in the right place.
1924                 $oldHelp = $help;
1925                 $help = [];
1926                 foreach ( $oldHelp as $k => $v ) {
1927                         if ( $k === 'submodules' ) {
1928                                 $help['permissions'] = '';
1929                         }
1930                         $help[$k] = $v;
1931                 }
1932                 $help['datatypes'] = '';
1933                 $help['templatedparams'] = '';
1934                 $help['credits'] = '';
1935
1936                 // Fill 'permissions'
1937                 $help['permissions'] .= Html::openElement( 'div',
1938                         [ 'class' => 'apihelp-block apihelp-permissions' ] );
1939                 $m = $this->msg( 'api-help-permissions' );
1940                 if ( !$m->isDisabled() ) {
1941                         $help['permissions'] .= Html::rawElement( 'div', [ 'class' => 'apihelp-block-head' ],
1942                                 $m->numParams( count( self::$mRights ) )->parse()
1943                         );
1944                 }
1945                 $help['permissions'] .= Html::openElement( 'dl' );
1946                 foreach ( self::$mRights as $right => $rightMsg ) {
1947                         $help['permissions'] .= Html::element( 'dt', null, $right );
1948
1949                         $rightMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )->parse();
1950                         $help['permissions'] .= Html::rawElement( 'dd', null, $rightMsg );
1951
1952                         $groups = array_map( function ( $group ) {
1953                                 return $group == '*' ? 'all' : $group;
1954                         }, $this->getPermissionManager()->getGroupsWithPermission( $right ) );
1955
1956                         $help['permissions'] .= Html::rawElement( 'dd', null,
1957                                 $this->msg( 'api-help-permissions-granted-to' )
1958                                         ->numParams( count( $groups ) )
1959                                         ->params( Message::listParam( $groups ) )
1960                                         ->parse()
1961                         );
1962                 }
1963                 $help['permissions'] .= Html::closeElement( 'dl' );
1964                 $help['permissions'] .= Html::closeElement( 'div' );
1965
1966                 // Fill 'datatypes', 'templatedparams', and 'credits', if applicable
1967                 if ( empty( $options['nolead'] ) ) {
1968                         $level = $options['headerlevel'];
1969                         $tocnumber = &$options['tocnumber'];
1970
1971                         $header = $this->msg( 'api-help-datatypes-header' )->parse();
1972
1973                         $id = Sanitizer::escapeIdForAttribute( 'main/datatypes', Sanitizer::ID_PRIMARY );
1974                         $idFallback = Sanitizer::escapeIdForAttribute( 'main/datatypes', Sanitizer::ID_FALLBACK );
1975                         $headline = Linker::makeHeadline( min( 6, $level ),
1976                                 ' class="apihelp-header">',
1977                                 $id,
1978                                 $header,
1979                                 '',
1980                                 $idFallback
1981                         );
1982                         // Ensure we have a sane anchor
1983                         if ( $id !== 'main/datatypes' && $idFallback !== 'main/datatypes' ) {
1984                                 $headline = '<div id="main/datatypes"></div>' . $headline;
1985                         }
1986                         $help['datatypes'] .= $headline;
1987                         $help['datatypes'] .= $this->msg( 'api-help-datatypes' )->parseAsBlock();
1988                         if ( !isset( $tocData['main/datatypes'] ) ) {
1989                                 $tocnumber[$level]++;
1990                                 $tocData['main/datatypes'] = [
1991                                         'toclevel' => count( $tocnumber ),
1992                                         'level' => $level,
1993                                         'anchor' => 'main/datatypes',
1994                                         'line' => $header,
1995                                         'number' => implode( '.', $tocnumber ),
1996                                         'index' => false,
1997                                 ];
1998                         }
1999
2000                         $header = $this->msg( 'api-help-templatedparams-header' )->parse();
2001
2002                         $id = Sanitizer::escapeIdForAttribute( 'main/templatedparams', Sanitizer::ID_PRIMARY );
2003                         $idFallback = Sanitizer::escapeIdForAttribute( 'main/templatedparams', Sanitizer::ID_FALLBACK );
2004                         $headline = Linker::makeHeadline( min( 6, $level ),
2005                                 ' class="apihelp-header">',
2006                                 $id,
2007                                 $header,
2008                                 '',
2009                                 $idFallback
2010                         );
2011                         // Ensure we have a sane anchor
2012                         if ( $id !== 'main/templatedparams' && $idFallback !== 'main/templatedparams' ) {
2013                                 $headline = '<div id="main/templatedparams"></div>' . $headline;
2014                         }
2015                         $help['templatedparams'] .= $headline;
2016                         $help['templatedparams'] .= $this->msg( 'api-help-templatedparams' )->parseAsBlock();
2017                         if ( !isset( $tocData['main/templatedparams'] ) ) {
2018                                 $tocnumber[$level]++;
2019                                 $tocData['main/templatedparams'] = [
2020                                         'toclevel' => count( $tocnumber ),
2021                                         'level' => $level,
2022                                         'anchor' => 'main/templatedparams',
2023                                         'line' => $header,
2024                                         'number' => implode( '.', $tocnumber ),
2025                                         'index' => false,
2026                                 ];
2027                         }
2028
2029                         $header = $this->msg( 'api-credits-header' )->parse();
2030                         $id = Sanitizer::escapeIdForAttribute( 'main/credits', Sanitizer::ID_PRIMARY );
2031                         $idFallback = Sanitizer::escapeIdForAttribute( 'main/credits', Sanitizer::ID_FALLBACK );
2032                         $headline = Linker::makeHeadline( min( 6, $level ),
2033                                 ' class="apihelp-header">',
2034                                 $id,
2035                                 $header,
2036                                 '',
2037                                 $idFallback
2038                         );
2039                         // Ensure we have a sane anchor
2040                         if ( $id !== 'main/credits' && $idFallback !== 'main/credits' ) {
2041                                 $headline = '<div id="main/credits"></div>' . $headline;
2042                         }
2043                         $help['credits'] .= $headline;
2044                         $help['credits'] .= $this->msg( 'api-credits' )->useDatabase( false )->parseAsBlock();
2045                         if ( !isset( $tocData['main/credits'] ) ) {
2046                                 $tocnumber[$level]++;
2047                                 $tocData['main/credits'] = [
2048                                         'toclevel' => count( $tocnumber ),
2049                                         'level' => $level,
2050                                         'anchor' => 'main/credits',
2051                                         'line' => $header,
2052                                         'number' => implode( '.', $tocnumber ),
2053                                         'index' => false,
2054                                 ];
2055                         }
2056                 }
2057         }
2058
2059         private $mCanApiHighLimits = null;
2060
2061         /**
2062          * Check whether the current user is allowed to use high limits
2063          * @return bool
2064          */
2065         public function canApiHighLimits() {
2066                 if ( !isset( $this->mCanApiHighLimits ) ) {
2067                         $this->mCanApiHighLimits = $this->getPermissionManager()
2068                                 ->userHasRight( $this->getUser(), 'apihighlimits' );
2069                 }
2070
2071                 return $this->mCanApiHighLimits;
2072         }
2073
2074         /**
2075          * Overrides to return this instance's module manager.
2076          * @return ApiModuleManager
2077          */
2078         public function getModuleManager() {
2079                 return $this->mModuleMgr;
2080         }
2081
2082         /**
2083          * Fetches the user agent used for this request
2084          *
2085          * The value will be the combination of the 'Api-User-Agent' header (if
2086          * any) and the standard User-Agent header (if any).
2087          *
2088          * @return string
2089          */
2090         public function getUserAgent() {
2091                 return trim(
2092                         $this->getRequest()->getHeader( 'Api-user-agent' ) . ' ' .
2093                         $this->getRequest()->getHeader( 'User-agent' )
2094                 );
2095         }
2096 }
2097
2098 /**
2099  * For really cool vim folding this needs to be at the end:
2100  * vim: foldmarker=@{,@} foldmethod=marker
2101  */