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         private $mCacheControl = [];
 157         private $mParamsUsed = [];
 158         private $mParamsSensitive = [];
 159
 160         /** @var bool|null Cached return value from self::lacksSameOriginSecurity() */
 161         private $lacksSameOriginSecurity = null;
 162
 163         /**
 164          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 165          *
 166          * @param IContextSource|WebRequest|null $context If this is an instance of
 167          *    FauxRequest, errors are thrown and no printing occurs
 168          * @param bool $enableWrite Should be set to true if the api may modify data
 169          */
 170         public function __construct( $context = null, $enableWrite = false ) {
 171                 if ( $context === null ) {
 172                         $context = RequestContext::getMain();
 173                 } elseif ( $context instanceof WebRequest ) {
 174                         // BC for pre-1.19
 175                         $request = $context;
 176                         $context = RequestContext::getMain();
 177                 }
 178                 // We set a derivative context so we can change stuff later
 179                 $this->setContext( new DerivativeContext( $context ) );
 180
 181                 if ( isset( $request ) ) {
 182                         $this->getContext()->setRequest( $request );
 183                 } else {
 184                         $request = $this->getRequest();
 185                 }
 186
 187                 $this->mInternalMode = ( $request instanceof FauxRequest );
 188
 189                 // Special handling for the main module: $parent === $this
 190                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 191
 192                 $config = $this->getConfig();
 193
 194                 if ( !$this->mInternalMode ) {
 195                         // Log if a request with a non-whitelisted Origin header is seen
 196                         // with session cookies.
 197                         $originHeader = $request->getHeader( 'Origin' );
 198                         if ( $originHeader === false ) {
 199                                 $origins = [];
 200                         } else {
 201                                 $originHeader = trim( $originHeader );
 202                                 $origins = preg_split( '/\s+/', $originHeader );
 203                         }
 204                         $sessionCookies = array_intersect(
 205                                 array_keys( $_COOKIE ),
 206                                 MediaWiki\Session\SessionManager::singleton()->getVaryCookies()
 207                         );
 208                         if ( $origins && $sessionCookies && (
 209                                 count( $origins ) !== 1 || !self::matchOrigin(
 210                                         $origins[0],
 211                                         $config->get( 'CrossSiteAJAXdomains' ),
 212                                         $config->get( 'CrossSiteAJAXdomainExceptions' )
 213                                 )
 214                         ) ) {
 215                                 LoggerFactory::getInstance( 'cors' )->warning(
 216                                         'Non-whitelisted CORS request with session cookies', [
 217                                                 'origin' => $originHeader,
 218                                                 'cookies' => $sessionCookies,
 219                                                 'ip' => $request->getIP(),
 220                                                 'userAgent' => $this->getUserAgent(),
 221                                                 'wiki' => WikiMap::getCurrentWikiDbDomain()->getId(),
 222                                         ]
 223                                 );
 224                         }
 225
 226                         // If we're in a mode that breaks the same-origin policy, strip
 227                         // user credentials for security.
 228                         if ( $this->lacksSameOriginSecurity() ) {
 229                                 global $wgUser;
 230                                 wfDebug( "API: stripping user credentials when the same-origin policy is not applied\n" );
 231                                 $wgUser = new User();
 232                                 $this->getContext()->setUser( $wgUser );
 233                                 $request->response()->header( 'MediaWiki-Login-Suppressed: true' );
 234                         }
 235                 }
 236
 237                 $this->mResult = new ApiResult( $this->getConfig()->get( 'APIMaxResultSize' ) );
 238
 239                 // Setup uselang. This doesn't use $this->getParameter()
 240                 // because we're not ready to handle errors yet.
 241                 $uselang = $request->getVal( 'uselang', self::API_DEFAULT_USELANG );
 242                 if ( $uselang === 'user' ) {
 243                         // Assume the parent context is going to return the user language
 244                         // for uselang=user (see T85635).
 245                 } else {
 246                         if ( $uselang === 'content' ) {
 247                                 $uselang = MediaWikiServices::getInstance()->getContentLanguage()->getCode();
 248                         }
 249                         $code = RequestContext::sanitizeLangCode( $uselang );
 250                         $this->getContext()->setLanguage( $code );
 251                         if ( !$this->mInternalMode ) {
 252                                 global $wgLang;
 253                                 $wgLang = $this->getContext()->getLanguage();
 254                                 RequestContext::getMain()->setLanguage( $wgLang );
 255                         }
 256                 }
 257
 258                 // Set up the error formatter. This doesn't use $this->getParameter()
 259                 // because we're not ready to handle errors yet.
 260                 $errorFormat = $request->getVal( 'errorformat', 'bc' );
 261                 $errorLangCode = $request->getVal( 'errorlang', 'uselang' );
 262                 $errorsUseDB = $request->getCheck( 'errorsuselocal' );
 263                 if ( in_array( $errorFormat, [ 'plaintext', 'wikitext', 'html', 'raw', 'none' ], true ) ) {
 264                         if ( $errorLangCode === 'uselang' ) {
 265                                 $errorLang = $this->getLanguage();
 266                         } elseif ( $errorLangCode === 'content' ) {
 267                                 $errorLang = MediaWikiServices::getInstance()->getContentLanguage();
 268                         } else {
 269                                 $errorLangCode = RequestContext::sanitizeLangCode( $errorLangCode );
 270                                 $errorLang = Language::factory( $errorLangCode );
 271                         }
 272                         $this->mErrorFormatter = new ApiErrorFormatter(
 273                                 $this->mResult, $errorLang, $errorFormat, $errorsUseDB
 274                         );
 275                 } else {
 276                         $this->mErrorFormatter = new ApiErrorFormatter_BackCompat( $this->mResult );
 277                 }
 278                 $this->mResult->setErrorFormatter( $this->getErrorFormatter() );
 279
 280                 $this->mModuleMgr = new ApiModuleManager( $this );
 281                 $this->mModuleMgr->addModules( self::$Modules, 'action' );
 282                 $this->mModuleMgr->addModules( $config->get( 'APIModules' ), 'action' );
 283                 $this->mModuleMgr->addModules( self::$Formats, 'format' );
 284                 $this->mModuleMgr->addModules( $config->get( 'APIFormatModules' ), 'format' );
 285
 286                 Hooks::run( 'ApiMain::moduleManager', [ $this->mModuleMgr ] );
 287
 288                 $this->mContinuationManager = null;
 289                 $this->mEnableWrite = $enableWrite;
 290
 291                 $this->mCdnMaxAge = -1; // flag for executeActionWithErrorHandling()
 292                 $this->mCommit = false;
 293         }
 294
 295         /**
 296          * Return true if the API was started by other PHP code using FauxRequest
 297          * @return bool
 298          */
 299         public function isInternalMode() {
 300                 return $this->mInternalMode;
 301         }
 302
 303         /**
 304          * Get the ApiResult object associated with current request
 305          *
 306          * @return ApiResult
 307          */
 308         public function getResult() {
 309                 return $this->mResult;
 310         }
 311
 312         /**
 313          * Get the security flag for the current request
 314          * @return bool
 315          */
 316         public function lacksSameOriginSecurity() {
 317                 if ( $this->lacksSameOriginSecurity !== null ) {
 318                         return $this->lacksSameOriginSecurity;
 319                 }
 320
 321                 $request = $this->getRequest();
 322
 323                 // JSONP mode
 324                 if ( $request->getCheck( 'callback' ) ) {
 325                         $this->lacksSameOriginSecurity = true;
 326                         return true;
 327                 }
 328
 329                 // Anonymous CORS
 330                 if ( $request->getVal( 'origin' ) === '*' ) {
 331                         $this->lacksSameOriginSecurity = true;
 332                         return true;
 333                 }
 334
 335                 // Header to be used from XMLHTTPRequest when the request might
 336                 // otherwise be used for XSS.
 337                 if ( $request->getHeader( 'Treat-as-Untrusted' ) !== false ) {
 338                         $this->lacksSameOriginSecurity = true;
 339                         return true;
 340                 }
 341
 342                 // Allow extensions to override.
 343                 $this->lacksSameOriginSecurity = !Hooks::run( 'RequestHasSameOriginSecurity', [ $request ] );
 344                 return $this->lacksSameOriginSecurity;
 345         }
 346
 347         /**
 348          * Get the ApiErrorFormatter object associated with current request
 349          * @return ApiErrorFormatter
 350          */
 351         public function getErrorFormatter() {
 352                 return $this->mErrorFormatter;
 353         }
 354
 355         /**
 356          * Get the continuation manager
 357          * @return ApiContinuationManager|null
 358          */
 359         public function getContinuationManager() {
 360                 return $this->mContinuationManager;
 361         }
 362
 363         /**
 364          * Set the continuation manager
 365          * @param ApiContinuationManager|null $manager
 366          */
 367         public function setContinuationManager( ApiContinuationManager $manager = null ) {
 368                 if ( $manager !== null && $this->mContinuationManager !== null ) {
 369                         throw new UnexpectedValueException(
 370                                 __METHOD__ . ': tried to set manager from ' . $manager->getSource() .
 371                                 ' when a manager is already set from ' . $this->mContinuationManager->getSource()
 372                         );
 373                 }
 374                 $this->mContinuationManager = $manager;
 375         }
 376
 377         /**
 378          * Get the API module object. Only works after executeAction()
 379          *
 380          * @return ApiBase
 381          */
 382         public function getModule() {
 383                 return $this->mModule;
 384         }
 385
 386         /**
 387          * Get the result formatter object. Only works after setupExecuteAction()
 388          *
 389          * @return ApiFormatBase
 390          */
 391         public function getPrinter() {
 392                 return $this->mPrinter;
 393         }
 394
 395         /**
 396          * Set how long the response should be cached.
 397          *
 398          * @param int $maxage
 399          */
 400         public function setCacheMaxAge( $maxage ) {
 401                 $this->setCacheControl( [
 402                         'max-age' => $maxage,
 403                         's-maxage' => $maxage
 404                 ] );
 405         }
 406
 407         /**
 408          * Set the type of caching headers which will be sent.
 409          *
 410          * @param string $mode One of:
 411          *    - 'public':     Cache this object in public caches, if the maxage or smaxage
 412          *         parameter is set, or if setCacheMaxAge() was called. If a maximum age is
 413          *         not provided by any of these means, the object will be private.
 414          *    - 'private':    Cache this object only in private client-side caches.
 415          *    - 'anon-public-user-private': Make this object cacheable for logged-out
 416          *         users, but private for logged-in users. IMPORTANT: If this is set, it must be
 417          *         set consistently for a given URL, it cannot be set differently depending on
 418          *         things like the contents of the database, or whether the user is logged in.
 419          *
 420          *  If the wiki does not allow anonymous users to read it, the mode set here
 421          *  will be ignored, and private caching headers will always be sent. In other words,
 422          *  the "public" mode is equivalent to saying that the data sent is as public as a page
 423          *  view.
 424          *
 425          *  For user-dependent data, the private mode should generally be used. The
 426          *  anon-public-user-private mode should only be used where there is a particularly
 427          *  good performance reason for caching the anonymous response, but where the
 428          *  response to logged-in users may differ, or may contain private data.
 429          *
 430          *  If this function is never called, then the default will be the private mode.
 431          */
 432         public function setCacheMode( $mode ) {
 433                 if ( !in_array( $mode, [ 'private', 'public', 'anon-public-user-private' ] ) ) {
 434                         wfDebug( __METHOD__ . ": unrecognised cache mode \"$mode\"\n" );
 435
 436                         // Ignore for forwards-compatibility
 437                         return;
 438                 }
 439
 440                 if ( !User::isEveryoneAllowed( 'read' ) ) {
 441                         // Private wiki, only private headers
 442                         if ( $mode !== 'private' ) {
 443                                 wfDebug( __METHOD__ . ": ignoring request for $mode cache mode, private wiki\n" );
 444
 445                                 return;
 446                         }
 447                 }
 448
 449                 if ( $mode === 'public' && $this->getParameter( 'uselang' ) === 'user' ) {
 450                         // User language is used for i18n, so we don't want to publicly
 451                         // cache. Anons are ok, because if they have non-default language
 452                         // then there's an appropriate Vary header set by whatever set
 453                         // their non-default language.
 454                         wfDebug( __METHOD__ . ": downgrading cache mode 'public' to " .
 455                                 "'anon-public-user-private' due to uselang=user\n" );
 456                         $mode = 'anon-public-user-private';
 457                 }
 458
 459                 wfDebug( __METHOD__ . ": setting cache mode $mode\n" );
 460                 $this->mCacheMode = $mode;
 461         }
 462
 463         /**
 464          * Set directives (key/value pairs) for the Cache-Control header.
 465          * Boolean values will be formatted as such, by including or omitting
 466          * without an equals sign.
 467          *
 468          * Cache control values set here will only be used if the cache mode is not
 469          * private, see setCacheMode().
 470          *
 471          * @param array $directives
 472          */
 473         public function setCacheControl( $directives ) {
 474                 $this->mCacheControl = $directives + $this->mCacheControl;
 475         }
 476
 477         /**
 478          * Create an instance of an output formatter by its name
 479          *
 480          * @param string $format
 481          *
 482          * @return ApiFormatBase
 483          */
 484         public function createPrinterByName( $format ) {
 485                 $printer = $this->mModuleMgr->getModule( $format, 'format', /* $ignoreCache */ true );
 486                 if ( $printer === null ) {
 487                         $this->dieWithError(
 488                                 [ 'apierror-unknownformat', wfEscapeWikiText( $format ) ], 'unknown_format'
 489                         );
 490                 }
 491
 492                 return $printer;
 493         }
 494
 495         /**
 496          * Execute api request. Any errors will be handled if the API was called by the remote client.
 497          */
 498         public function execute() {
 499                 if ( $this->mInternalMode ) {
 500                         $this->executeAction();
 501                 } else {
 502                         $this->executeActionWithErrorHandling();
 503                 }
 504         }
 505
 506         /**
 507          * Execute an action, and in case of an error, erase whatever partial results
 508          * have been accumulated, and replace it with an error message and a help screen.
 509          */
 510         protected function executeActionWithErrorHandling() {
 511                 // Verify the CORS header before executing the action
 512                 if ( !$this->handleCORS() ) {
 513                         // handleCORS() has sent a 403, abort
 514                         return;
 515                 }
 516
 517                 // Exit here if the request method was OPTIONS
 518                 // (assume there will be a followup GET or POST)
 519                 if ( $this->getRequest()->getMethod() === 'OPTIONS' ) {
 520                         return;
 521                 }
 522
 523                 // In case an error occurs during data output,
 524                 // clear the output buffer and print just the error information
 525                 $obLevel = ob_get_level();
 526                 ob_start();
 527
 528                 $t = microtime( true );
 529                 $isError = false;
 530                 try {
 531                         $this->executeAction();
 532                         $runTime = microtime( true ) - $t;
 533                         $this->logRequest( $runTime );
 534                         MediaWikiServices::getInstance()->getStatsdDataFactory()->timing(
 535                                 'api.' . $this->mModule->getModuleName() . '.executeTiming', 1000 * $runTime
 536                         );
 537                 } catch ( Exception $e ) { // @todo Remove this block when HHVM is no longer supported
 538                         $this->handleException( $e );
 539                         $this->logRequest( microtime( true ) - $t, $e );
 540                         $isError = true;
 541                 } catch ( Throwable $e ) {
 542                         $this->handleException( $e );
 543                         $this->logRequest( microtime( true ) - $t, $e );
 544                         $isError = true;
 545                 }
 546
 547                 // Commit DBs and send any related cookies and headers
 548                 MediaWiki::preOutputCommit( $this->getContext() );
 549
 550                 // Send cache headers after any code which might generate an error, to
 551                 // avoid sending public cache headers for errors.
 552                 $this->sendCacheHeaders( $isError );
 553
 554                 // Executing the action might have already messed with the output
 555                 // buffers.
 556                 while ( ob_get_level() > $obLevel ) {
 557                         ob_end_flush();
 558                 }
 559         }
 560
 561         /**
 562          * Handle an exception as an API response
 563          *
 564          * @since 1.23
 565          * @param Exception|Throwable $e
 566          */
 567         protected function handleException( $e ) {
 568                 // T65145: Rollback any open database transactions
 569                 if ( !$e instanceof ApiUsageException ) {
 570                         // ApiUsageExceptions are intentional, so don't rollback if that's the case
 571                         MWExceptionHandler::rollbackMasterChangesAndLog( $e );
 572                 }
 573
 574                 // Allow extra cleanup and logging
 575                 Hooks::run( 'ApiMain::onException', [ $this, $e ] );
 576
 577                 // Handle any kind of exception by outputting properly formatted error message.
 578                 // If this fails, an unhandled exception should be thrown so that global error
 579                 // handler will process and log it.
 580
 581                 $errCodes = $this->substituteResultWithError( $e );
 582
 583                 // Error results should not be cached
 584                 $this->setCacheMode( 'private' );
 585
 586                 $response = $this->getRequest()->response();
 587                 $headerStr = 'MediaWiki-API-Error: ' . implode( ', ', $errCodes );
 588                 $response->header( $headerStr );
 589
 590                 // Reset and print just the error message
 591                 ob_clean();
 592
 593                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 594                 $this->createErrorPrinter();
 595
 596                 // Get desired HTTP code from an ApiUsageException. Don't use codes from other
 597                 // exception types, as they are unlikely to be intended as an HTTP code.
 598                 $httpCode = $e instanceof ApiUsageException ? $e->getCode() : 0;
 599
 600                 $failed = false;
 601                 try {
 602                         $this->printResult( $httpCode );
 603                 } catch ( ApiUsageException $ex ) {
 604                         // The error printer itself is failing. Try suppressing its request
 605                         // parameters and redo.
 606                         $failed = true;
 607                         $this->addWarning( 'apiwarn-errorprinterfailed' );
 608                         foreach ( $ex->getStatusValue()->getErrors() as $error ) {
 609                                 try {
 610                                         $this->mPrinter->addWarning( $error );
 611                                 } catch ( Exception $ex2 ) { // @todo Remove this block when HHVM is no longer supported
 612                                         // WTF?
 613                                         $this->addWarning( $error );
 614                                 } catch ( Throwable $ex2 ) {
 615                                         // WTF?
 616                                         $this->addWarning( $error );
 617                                 }
 618                         }
 619                 }
 620                 if ( $failed ) {
 621                         $this->mPrinter = null;
 622                         $this->createErrorPrinter();
 623                         $this->mPrinter->forceDefaultParams();
 624                         if ( $httpCode ) {
 625                                 $response->statusHeader( 200 ); // Reset in case the fallback doesn't want a non-200
 626                         }
 627                         $this->printResult( $httpCode );
 628                 }
 629         }
 630
 631         /**
 632          * Handle an exception from the ApiBeforeMain hook.
 633          *
 634          * This tries to print the exception as an API response, to be more
 635          * friendly to clients. If it fails, it will rethrow the exception.
 636          *
 637          * @since 1.23
 638          * @param Exception|Throwable $e
 639          * @throws Exception|Throwable
 640          */
 641         public static function handleApiBeforeMainException( $e ) {
 642                 ob_start();
 643
 644                 try {
 645                         $main = new self( RequestContext::getMain(), false );
 646                         $main->handleException( $e );
 647                         $main->logRequest( 0, $e );
 648                 } catch ( Exception $e2 ) { // @todo Remove this block when HHVM is no longer supported
 649                         // Nope, even that didn't work. Punt.
 650                         throw $e;
 651                 } catch ( Throwable $e2 ) {
 652                         // Nope, even that didn't work. Punt.
 653                         throw $e;
 654                 }
 655
 656                 // Reset cache headers
 657                 $main->sendCacheHeaders( true );
 658
 659                 ob_end_flush();
 660         }
 661
 662         /**
 663          * Check the &origin= query parameter against the Origin: HTTP header and respond appropriately.
 664          *
 665          * If no origin parameter is present, nothing happens.
 666          * If an origin parameter is present but doesn't match the Origin header, a 403 status code
 667          * is set and false is returned.
 668          * If the parameter and the header do match, the header is checked against $wgCrossSiteAJAXdomains
 669          * and $wgCrossSiteAJAXdomainExceptions, and if the origin qualifies, the appropriate CORS
 670          * headers are set.
 671          * https://www.w3.org/TR/cors/#resource-requests
 672          * https://www.w3.org/TR/cors/#resource-preflight-requests
 673          *
 674          * @return bool False if the caller should abort (403 case), true otherwise (all other cases)
 675          */
 676         protected function handleCORS() {
 677                 $originParam = $this->getParameter( 'origin' ); // defaults to null
 678                 if ( $originParam === null ) {
 679                         // No origin parameter, nothing to do
 680                         return true;
 681                 }
 682
 683                 $request = $this->getRequest();
 684                 $response = $request->response();
 685
 686                 $matchedOrigin = false;
 687                 $allowTiming = false;
 688                 $varyOrigin = true;
 689
 690                 if ( $originParam === '*' ) {
 691                         // Request for anonymous CORS
 692                         // Technically we should check for the presence of an Origin header
 693                         // and not process it as CORS if it's not set, but that would
 694                         // require us to vary on Origin for all 'origin=*' requests which
 695                         // we don't want to do.
 696                         $matchedOrigin = true;
 697                         $allowOrigin = '*';
 698                         $allowCredentials = 'false';
 699                         $varyOrigin = false; // No need to vary
 700                 } else {
 701                         // Non-anonymous CORS, check we allow the domain
 702
 703                         // Origin: header is a space-separated list of origins, check all of them
 704                         $originHeader = $request->getHeader( 'Origin' );
 705                         if ( $originHeader === false ) {
 706                                 $origins = [];
 707                         } else {
 708                                 $originHeader = trim( $originHeader );
 709                                 $origins = preg_split( '/\s+/', $originHeader );
 710                         }
 711
 712                         if ( !in_array( $originParam, $origins ) ) {
 713                                 // origin parameter set but incorrect
 714                                 // Send a 403 response
 715                                 $response->statusHeader( 403 );
 716                                 $response->header( 'Cache-Control: no-cache' );
 717                                 echo "'origin' parameter does not match Origin header\n";
 718
 719                                 return false;
 720                         }
 721
 722                         $config = $this->getConfig();
 723                         $matchedOrigin = count( $origins ) === 1 && self::matchOrigin(
 724                                 $originParam,
 725                                 $config->get( 'CrossSiteAJAXdomains' ),
 726                                 $config->get( 'CrossSiteAJAXdomainExceptions' )
 727                         );
 728
 729                         $allowOrigin = $originHeader;
 730                         $allowCredentials = 'true';
 731                         $allowTiming = $originHeader;
 732                 }
 733
 734                 if ( $matchedOrigin ) {
 735                         $requestedMethod = $request->getHeader( 'Access-Control-Request-Method' );
 736                         $preflight = $request->getMethod() === 'OPTIONS' && $requestedMethod !== false;
 737                         if ( $preflight ) {
 738                                 // This is a CORS preflight request
 739                                 if ( $requestedMethod !== 'POST' && $requestedMethod !== 'GET' ) {
 740                                         // If method is not a case-sensitive match, do not set any additional headers and terminate.
 741                                         $response->header( 'MediaWiki-CORS-Rejection: Unsupported method requested in preflight' );
 742                                         return true;
 743                                 }
 744                                 // We allow the actual request to send the following headers
 745                                 $requestedHeaders = $request->getHeader( 'Access-Control-Request-Headers' );
 746                                 if ( $requestedHeaders !== false ) {
 747                                         if ( !self::matchRequestedHeaders( $requestedHeaders ) ) {
 748                                                 $response->header( 'MediaWiki-CORS-Rejection: Unsupported header requested in preflight' );
 749                                                 return true;
 750                                         }
 751                                         $response->header( 'Access-Control-Allow-Headers: ' . $requestedHeaders );
 752                                 }
 753
 754                                 // We only allow the actual request to be GET or POST
 755                                 $response->header( 'Access-Control-Allow-Methods: POST, GET' );
 756                         } elseif ( $request->getMethod() !== 'POST' && $request->getMethod() !== 'GET' ) {
 757                                 // Unsupported non-preflight method, don't handle it as CORS
 758                                 $response->header(
 759                                         'MediaWiki-CORS-Rejection: Unsupported method for simple request or actual request'
 760                                 );
 761                                 return true;
 762                         }
 763
 764                         $response->header( "Access-Control-Allow-Origin: $allowOrigin" );
 765                         $response->header( "Access-Control-Allow-Credentials: $allowCredentials" );
 766                         // https://www.w3.org/TR/resource-timing/#timing-allow-origin
 767                         if ( $allowTiming !== false ) {
 768                                 $response->header( "Timing-Allow-Origin: $allowTiming" );
 769                         }
 770
 771                         if ( !$preflight ) {
 772                                 $response->header(
 773                                         'Access-Control-Expose-Headers: MediaWiki-API-Error, Retry-After, X-Database-Lag, '
 774                                         . 'MediaWiki-Login-Suppressed'
 775                                 );
 776                         }
 777                 } else {
 778                         $response->header( 'MediaWiki-CORS-Rejection: Origin mismatch' );
 779                 }
 780
 781                 if ( $varyOrigin ) {
 782                         $this->getOutput()->addVaryHeader( 'Origin' );
 783                 }
 784
 785                 return true;
 786         }
 787
 788         /**
 789          * Attempt to match an Origin header against a set of rules and a set of exceptions
 790          * @param string $value Origin header
 791          * @param array $rules Set of wildcard rules
 792          * @param array $exceptions Set of wildcard rules
 793          * @return bool True if $value matches a rule in $rules and doesn't match
 794          *    any rules in $exceptions, false otherwise
 795          */
 796         protected static function matchOrigin( $value, $rules, $exceptions ) {
 797                 foreach ( $rules as $rule ) {
 798                         if ( preg_match( self::wildcardToRegex( $rule ), $value ) ) {
 799                                 // Rule matches, check exceptions
 800                                 foreach ( $exceptions as $exc ) {
 801                                         if ( preg_match( self::wildcardToRegex( $exc ), $value ) ) {
 802                                                 return false;
 803                                         }
 804                                 }
 805
 806                                 return true;
 807                         }
 808                 }
 809
 810                 return false;
 811         }
 812
 813         /**
 814          * Attempt to validate the value of Access-Control-Request-Headers against a list
 815          * of headers that we allow the follow up request to send.
 816          *
 817          * @param string $requestedHeaders Comma separated list of HTTP headers
 818          * @return bool True if all requested headers are in the list of allowed headers
 819          */
 820         protected static function matchRequestedHeaders( $requestedHeaders ) {
 821                 if ( trim( $requestedHeaders ) === '' ) {
 822                         return true;
 823                 }
 824                 $requestedHeaders = explode( ',', $requestedHeaders );
 825                 $allowedAuthorHeaders = array_flip( [
 826                         /* simple headers (see spec) */
 827                         'accept',
 828                         'accept-language',
 829                         'content-language',
 830                         'content-type',
 831                         /* non-authorable headers in XHR, which are however requested by some UAs */
 832                         'accept-encoding',
 833                         'dnt',
 834                         'origin',
 835                         /* MediaWiki whitelist */
 836                         'user-agent',
 837                         'api-user-agent',
 838                 ] );
 839                 foreach ( $requestedHeaders as $rHeader ) {
 840                         $rHeader = strtolower( trim( $rHeader ) );
 841                         if ( !isset( $allowedAuthorHeaders[$rHeader] ) ) {
 842                                 LoggerFactory::getInstance( 'api-warning' )->warning(
 843                                         'CORS preflight failed on requested header: {header}', [
 844                                                 'header' => $rHeader
 845                                         ]
 846                                 );
 847                                 return false;
 848                         }
 849                 }
 850                 return true;
 851         }
 852
 853         /**
 854          * Helper function to convert wildcard string into a regex
 855          * '*' => '.*?'
 856          * '?' => '.'
 857          *
 858          * @param string $wildcard String with wildcards
 859          * @return string Regular expression
 860          */
 861         protected static function wildcardToRegex( $wildcard ) {
 862                 $wildcard = preg_quote( $wildcard, '/' );
 863                 $wildcard = str_replace(
 864                         [ '\*', '\?' ],
 865                         [ '.*?', '.' ],
 866                         $wildcard
 867                 );
 868
 869                 return "/^https?:\/\/$wildcard$/";
 870         }
 871
 872         /**
 873          * Send caching headers
 874          * @param bool $isError Whether an error response is being output
 875          * @since 1.26 added $isError parameter
 876          */
 877         protected function sendCacheHeaders( $isError ) {
 878                 $response = $this->getRequest()->response();
 879                 $out = $this->getOutput();
 880
 881                 $out->addVaryHeader( 'Treat-as-Untrusted' );
 882
 883                 $config = $this->getConfig();
 884
 885                 if ( $config->get( 'VaryOnXFP' ) ) {
 886                         $out->addVaryHeader( 'X-Forwarded-Proto' );
 887                 }
 888
 889                 if ( !$isError && $this->mModule &&
 890                         ( $this->getRequest()->getMethod() === 'GET' || $this->getRequest()->getMethod() === 'HEAD' )
 891                 ) {
 892                         $etag = $this->mModule->getConditionalRequestData( 'etag' );
 893                         if ( $etag !== null ) {
 894                                 $response->header( "ETag: $etag" );
 895                         }
 896                         $lastMod = $this->mModule->getConditionalRequestData( 'last-modified' );
 897                         if ( $lastMod !== null ) {
 898                                 $response->header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $lastMod ) );
 899                         }
 900                 }
 901
 902                 // The logic should be:
 903                 // $this->mCacheControl['max-age'] is set?
 904                 //    Use it, the module knows better than our guess.
 905                 // !$this->mModule || $this->mModule->isWriteMode(), and mCacheMode is private?
 906                 //    Use 0 because we can guess caching is probably the wrong thing to do.
 907                 // Use $this->getParameter( 'maxage' ), which already defaults to 0.
 908                 $maxage = 0;
 909                 if ( isset( $this->mCacheControl['max-age'] ) ) {
 910                         $maxage = $this->mCacheControl['max-age'];
 911                 } elseif ( ( $this->mModule && !$this->mModule->isWriteMode() ) ||
 912                         $this->mCacheMode !== 'private'
 913                 ) {
 914                         $maxage = $this->getParameter( 'maxage' );
 915                 }
 916                 $privateCache = 'private, must-revalidate, max-age=' . $maxage;
 917
 918                 if ( $this->mCacheMode == 'private' ) {
 919                         $response->header( "Cache-Control: $privateCache" );
 920                         return;
 921                 }
 922
 923                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 924                         $out->addVaryHeader( 'Cookie' );
 925                         $response->header( $out->getVaryHeader() );
 926                         if ( MediaWiki\Session\SessionManager::getGlobalSession()->isPersistent() ) {
 927                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 928                                 // Mark request private
 929                                 $response->header( "Cache-Control: $privateCache" );
 930
 931                                 return;
 932                         } // else anonymous, send public headers below
 933                 }
 934
 935                 // Send public headers
 936                 $response->header( $out->getVaryHeader() );
 937
 938                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 939                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 940                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 941                 }
 942                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 943                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 944                 }
 945
 946                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 947                         // Public cache not requested
 948                         // Sending a Vary header in this case is harmless, and protects us
 949                         // against conditional calls of setCacheMaxAge().
 950                         $response->header( "Cache-Control: $privateCache" );
 951
 952                         return;
 953                 }
 954
 955                 $this->mCacheControl['public'] = true;
 956
 957                 // Send an Expires header
 958                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 959                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 960                 $response->header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 961
 962                 // Construct the Cache-Control header
 963                 $ccHeader = '';
 964                 $separator = '';
 965                 foreach ( $this->mCacheControl as $name => $value ) {
 966                         if ( is_bool( $value ) ) {
 967                                 if ( $value ) {
 968                                         $ccHeader .= $separator . $name;
 969                                         $separator = ', ';
 970                                 }
 971                         } else {
 972                                 $ccHeader .= $separator . "$name=$value";
 973                                 $separator = ', ';
 974                         }
 975                 }
 976
 977                 $response->header( "Cache-Control: $ccHeader" );
 978         }
 979
 980         /**
 981          * Create the printer for error output
 982          */
 983         private function createErrorPrinter() {
 984                 if ( !isset( $this->mPrinter ) ) {
 985                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 986                         if ( !$this->mModuleMgr->isDefined( $value, 'format' ) ) {
 987                                 $value = self::API_DEFAULT_FORMAT;
 988                         }
 989                         $this->mPrinter = $this->createPrinterByName( $value );
 990                 }
 991
 992                 // Printer may not be able to handle errors. This is particularly
 993                 // likely if the module returns something for getCustomPrinter().
 994                 if ( !$this->mPrinter->canPrintErrors() ) {
 995                         $this->mPrinter = $this->createPrinterByName( self::API_DEFAULT_FORMAT );
 996                 }
 997         }
 998
 999         /**
1000          * Create an error message for the given exception.
1001          *
1002          * If an ApiUsageException, errors/warnings will be extracted from the
1003          * embedded StatusValue.
1004          *
1005          * Any other exception will be returned with a generic code and wrapper
1006          * text around the exception's (presumably English) message as a single
1007          * error (no warnings).
1008          *
1009          * @param Exception|Throwable $e
1010          * @param string $type 'error' or 'warning'
1011          * @return ApiMessage[]
1012          * @since 1.27
1013          */
1014         protected function errorMessagesFromException( $e, $type = 'error' ) {
1015                 $messages = [];
1016                 if ( $e instanceof ApiUsageException ) {
1017                         foreach ( $e->getStatusValue()->getErrorsByType( $type ) as $error ) {
1018                                 $messages[] = ApiMessage::create( $error );
1019                         }
1020                 } elseif ( $type !== 'error' ) {
1021                         // None of the rest have any messages for non-error types
1022                 } else {
1023                         // Something is seriously wrong
1024                         $config = $this->getConfig();
1025                         // TODO: Avoid embedding arbitrary class names in the error code.
1026                         $class = preg_replace( '#^Wikimedia\\\Rdbms\\\#', '', get_class( $e ) );
1027                         $code = 'internal_api_error_' . $class;
1028                         $data = [ 'errorclass' => get_class( $e ) ];
1029                         if ( $config->get( 'ShowExceptionDetails' ) ) {
1030                                 if ( $e instanceof ILocalizedException ) {
1031                                         $msg = $e->getMessageObject();
1032                                 } elseif ( $e instanceof MessageSpecifier ) {
1033                                         $msg = Message::newFromSpecifier( $e );
1034                                 } else {
1035                                         $msg = wfEscapeWikiText( $e->getMessage() );
1036                                 }
1037                                 $params = [ 'apierror-exceptioncaught', WebRequest::getRequestId(), $msg ];
1038                         } else {
1039                                 $params = [ 'apierror-exceptioncaughttype', WebRequest::getRequestId(), get_class( $e ) ];
1040                         }
1041
1042                         $messages[] = ApiMessage::create( $params, $code, $data );
1043                 }
1044                 return $messages;
1045         }
1046
1047         /**
1048          * Replace the result data with the information about an exception.
1049          * @param Exception|Throwable $e
1050          * @return string[] Error codes
1051          */
1052         protected function substituteResultWithError( $e ) {
1053                 $result = $this->getResult();
1054                 $formatter = $this->getErrorFormatter();
1055                 $config = $this->getConfig();
1056                 $errorCodes = [];
1057
1058                 // Remember existing warnings and errors across the reset
1059                 $errors = $result->getResultData( [ 'errors' ] );
1060                 $warnings = $result->getResultData( [ 'warnings' ] );
1061                 $result->reset();
1062                 if ( $warnings !== null ) {
1063                         $result->addValue( null, 'warnings', $warnings, ApiResult::NO_SIZE_CHECK );
1064                 }
1065                 if ( $errors !== null ) {
1066                         $result->addValue( null, 'errors', $errors, ApiResult::NO_SIZE_CHECK );
1067
1068                         // Collect the copied error codes for the return value
1069                         foreach ( $errors as $error ) {
1070                                 if ( isset( $error['code'] ) ) {
1071                                         $errorCodes[$error['code']] = true;
1072                                 }
1073                         }
1074                 }
1075
1076                 // Add errors from the exception
1077                 $modulePath = $e instanceof ApiUsageException ? $e->getModulePath() : null;
1078                 foreach ( $this->errorMessagesFromException( $e, 'error' ) as $msg ) {
1079                         if ( ApiErrorFormatter::isValidApiCode( $msg->getApiCode() ) ) {
1080                                 $errorCodes[$msg->getApiCode()] = true;
1081                         } else {
1082                                 LoggerFactory::getInstance( 'api-warning' )->error( 'Invalid API error code "{code}"', [
1083                                         'code' => $msg->getApiCode(),
1084                                         'exception' => $e,
1085                                 ] );
1086                                 $errorCodes['<invalid-code>'] = true;
1087                         }
1088                         $formatter->addError( $modulePath, $msg );
1089                 }
1090                 foreach ( $this->errorMessagesFromException( $e, 'warning' ) as $msg ) {
1091                         $formatter->addWarning( $modulePath, $msg );
1092                 }
1093
1094                 // Add additional data. Path depends on whether we're in BC mode or not.
1095                 // Data depends on the type of exception.
1096                 if ( $formatter instanceof ApiErrorFormatter_BackCompat ) {
1097                         $path = [ 'error' ];
1098                 } else {
1099                         $path = null;
1100                 }
1101                 if ( $e instanceof ApiUsageException ) {
1102                         $link = wfExpandUrl( wfScript( 'api' ) );
1103                         $result->addContentValue(
1104                                 $path,
1105                                 'docref',
1106                                 trim(
1107                                         $this->msg( 'api-usage-docref', $link )->inLanguage( $formatter->getLanguage() )->text()
1108                                         . ' '
1109                                         . $this->msg( 'api-usage-mailinglist-ref' )->inLanguage( $formatter->getLanguage() )->text()
1110                                 )
1111                         );
1112                 } elseif ( $config->get( 'ShowExceptionDetails' ) ) {
1113                         $result->addContentValue(
1114                                 $path,
1115                                 'trace',
1116                                 $this->msg( 'api-exception-trace',
1117                                         get_class( $e ),
1118                                         $e->getFile(),
1119                                         $e->getLine(),
1120                                         MWExceptionHandler::getRedactedTraceAsString( $e )
1121                                 )->inLanguage( $formatter->getLanguage() )->text()
1122                         );
1123                 }
1124
1125                 // Add the id and such
1126                 $this->addRequestedFields( [ 'servedby' ] );
1127
1128                 return array_keys( $errorCodes );
1129         }
1130
1131         /**
1132          * Add requested fields to the result
1133          * @param string[] $force Which fields to force even if not requested. Accepted values are:
1134          *  - servedby
1135          */
1136         protected function addRequestedFields( $force = [] ) {
1137                 $result = $this->getResult();
1138
1139                 $requestid = $this->getParameter( 'requestid' );
1140                 if ( $requestid !== null ) {
1141                         $result->addValue( null, 'requestid', $requestid, ApiResult::NO_SIZE_CHECK );
1142                 }
1143
1144                 if ( $this->getConfig()->get( 'ShowHostnames' ) && (
1145                         in_array( 'servedby', $force, true ) || $this->getParameter( 'servedby' )
1146                 ) ) {
1147                         $result->addValue( null, 'servedby', wfHostname(), ApiResult::NO_SIZE_CHECK );
1148                 }
1149
1150                 if ( $this->getParameter( 'curtimestamp' ) ) {
1151                         $result->addValue( null, 'curtimestamp', wfTimestamp( TS_ISO_8601, time() ),
1152                                 ApiResult::NO_SIZE_CHECK );
1153                 }
1154
1155                 if ( $this->getParameter( 'responselanginfo' ) ) {
1156                         $result->addValue( null, 'uselang', $this->getLanguage()->getCode(),
1157                                 ApiResult::NO_SIZE_CHECK );
1158                         $result->addValue( null, 'errorlang', $this->getErrorFormatter()->getLanguage()->getCode(),
1159                                 ApiResult::NO_SIZE_CHECK );
1160                 }
1161         }
1162
1163         /**
1164          * Set up for the execution.
1165          * @return array
1166          */
1167         protected function setupExecuteAction() {
1168                 $this->addRequestedFields();
1169
1170                 $params = $this->extractRequestParams();
1171                 $this->mAction = $params['action'];
1172
1173                 return $params;
1174         }
1175
1176         /**
1177          * Set up the module for response
1178          * @return ApiBase The module that will handle this action
1179          * @throws MWException
1180          * @throws ApiUsageException
1181          */
1182         protected function setupModule() {
1183                 // Instantiate the module requested by the user
1184                 $module = $this->mModuleMgr->getModule( $this->mAction, 'action' );
1185                 if ( $module === null ) {
1186                         // Probably can't happen
1187                         // @codeCoverageIgnoreStart
1188                         $this->dieWithError(
1189                                 [ 'apierror-unknownaction', wfEscapeWikiText( $this->mAction ) ], 'unknown_action'
1190                         );
1191                         // @codeCoverageIgnoreEnd
1192                 }
1193                 $moduleParams = $module->extractRequestParams();
1194
1195                 // Check token, if necessary
1196                 if ( $module->needsToken() === true ) {
1197                         throw new MWException(
1198                                 "Module '{$module->getModuleName()}' must be updated for the new token handling. " .
1199                                 'See documentation for ApiBase::needsToken for details.'
1200                         );
1201                 }
1202                 if ( $module->needsToken() ) {
1203                         if ( !$module->mustBePosted() ) {
1204                                 throw new MWException(
1205                                         "Module '{$module->getModuleName()}' must require POST to use tokens."
1206                                 );
1207                         }
1208
1209                         if ( !isset( $moduleParams['token'] ) ) {
1210                                 // Probably can't happen
1211                                 // @codeCoverageIgnoreStart
1212                                 $module->dieWithError( [ 'apierror-missingparam', 'token' ] );
1213                                 // @codeCoverageIgnoreEnd
1214                         }
1215
1216                         $module->requirePostedParameters( [ 'token' ] );
1217
1218                         if ( !$module->validateToken( $moduleParams['token'], $moduleParams ) ) {
1219                                 $module->dieWithError( 'apierror-badtoken' );
1220                         }
1221                 }
1222
1223                 return $module;
1224         }
1225
1226         /**
1227          * @return array
1228          */
1229         private function getMaxLag() {
1230                 $dbLag = MediaWikiServices::getInstance()->getDBLoadBalancer()->getMaxLag();
1231                 $lagInfo = [
1232                         'host' => $dbLag[0],
1233                         'lag' => $dbLag[1],
1234                         'type' => 'db'
1235                 ];
1236
1237                 $jobQueueLagFactor = $this->getConfig()->get( 'JobQueueIncludeInMaxLagFactor' );
1238                 if ( $jobQueueLagFactor ) {
1239                         // Turn total number of jobs into seconds by using the configured value
1240                         $totalJobs = array_sum( JobQueueGroup::singleton()->getQueueSizes() );
1241                         $jobQueueLag = $totalJobs / (float)$jobQueueLagFactor;
1242                         if ( $jobQueueLag > $lagInfo['lag'] ) {
1243                                 $lagInfo = [
1244                                         'host' => wfHostname(), // XXX: Is there a better value that could be used?
1245                                         'lag' => $jobQueueLag,
1246                                         'type' => 'jobqueue',
1247                                         'jobs' => $totalJobs,
1248                                 ];
1249                         }
1250                 }
1251
1252                 Hooks::runWithoutAbort( 'ApiMaxLagInfo', [ &$lagInfo ] );
1253
1254                 return $lagInfo;
1255         }
1256
1257         /**
1258          * Check the max lag if necessary
1259          * @param ApiBase $module Api module being used
1260          * @param array $params Array an array containing the request parameters.
1261          * @return bool True on success, false should exit immediately
1262          */
1263         protected function checkMaxLag( $module, $params ) {
1264                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
1265                         $maxLag = $params['maxlag'];
1266                         $lagInfo = $this->getMaxLag();
1267                         if ( $lagInfo['lag'] > $maxLag ) {
1268                                 $response = $this->getRequest()->response();
1269
1270                                 $response->header( 'Retry-After: ' . max( (int)$maxLag, 5 ) );
1271                                 $response->header( 'X-Database-Lag: ' . (int)$lagInfo['lag'] );
1272
1273                                 if ( $this->getConfig()->get( 'ShowHostnames' ) ) {
1274                                         $this->dieWithError(
1275                                                 [ 'apierror-maxlag', $lagInfo['lag'], $lagInfo['host'] ],
1276                                                 'maxlag',
1277                                                 $lagInfo
1278                                         );
1279                                 }
1280
1281                                 $this->dieWithError( [ 'apierror-maxlag-generic', $lagInfo['lag'] ], 'maxlag', $lagInfo );
1282                         }
1283                 }
1284
1285                 return true;
1286         }
1287
1288         /**
1289          * Check selected RFC 7232 precondition headers
1290          *
1291          * RFC 7232 envisions a particular model where you send your request to "a
1292          * resource", and for write requests that you can read "the resource" by
1293          * changing the method to GET. When the API receives a GET request, it
1294          * works out even though "the resource" from RFC 7232's perspective might
1295          * be many resources from MediaWiki's perspective. But it totally fails for
1296          * a POST, since what HTTP sees as "the resource" is probably just
1297          * "/api.php" with all the interesting bits in the body.
1298          *
1299          * Therefore, we only support RFC 7232 precondition headers for GET (and
1300          * HEAD). That means we don't need to bother with If-Match and
1301          * If-Unmodified-Since since they only apply to modification requests.
1302          *
1303          * And since we don't support Range, If-Range is ignored too.
1304          *
1305          * @since 1.26
1306          * @param ApiBase $module Api module being used
1307          * @return bool True on success, false should exit immediately
1308          */
1309         protected function checkConditionalRequestHeaders( $module ) {
1310                 if ( $this->mInternalMode ) {
1311                         // No headers to check in internal mode
1312                         return true;
1313                 }
1314
1315                 if ( $this->getRequest()->getMethod() !== 'GET' && $this->getRequest()->getMethod() !== 'HEAD' ) {
1316                         // Don't check POSTs
1317                         return true;
1318                 }
1319
1320                 $return304 = false;
1321
1322                 $ifNoneMatch = array_diff(
1323                         $this->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST ) ?: [],
1324                         [ '' ]
1325                 );
1326                 if ( $ifNoneMatch ) {
1327                         if ( $ifNoneMatch === [ '*' ] ) {
1328                                 // API responses always "exist"
1329                                 $etag = '*';
1330                         } else {
1331                                 $etag = $module->getConditionalRequestData( 'etag' );
1332                         }
1333                 }
1334                 if ( $ifNoneMatch && $etag !== null ) {
1335                         $test = substr( $etag, 0, 2 ) === 'W/' ? substr( $etag, 2 ) : $etag;
1336                         $match = array_map( function ( $s ) {
1337                                 return substr( $s, 0, 2 ) === 'W/' ? substr( $s, 2 ) : $s;
1338                         }, $ifNoneMatch );
1339                         $return304 = in_array( $test, $match, true );
1340                 } else {
1341                         $value = trim( $this->getRequest()->getHeader( 'If-Modified-Since' ) );
1342
1343                         // Some old browsers sends sizes after the date, like this:
1344                         //  Wed, 20 Aug 2003 06:51:19 GMT; length=5202
1345                         // Ignore that.
1346                         $i = strpos( $value, ';' );
1347                         if ( $i !== false ) {
1348                                 $value = trim( substr( $value, 0, $i ) );
1349                         }
1350
1351                         if ( $value !== '' ) {
1352                                 try {
1353                                         $ts = new MWTimestamp( $value );
1354                                         if (
1355                                                 // RFC 7231 IMF-fixdate
1356                                                 $ts->getTimestamp( TS_RFC2822 ) === $value ||
1357                                                 // RFC 850
1358                                                 $ts->format( 'l, d-M-y H:i:s' ) . ' GMT' === $value ||
1359                                                 // asctime (with and without space-padded day)
1360                                                 $ts->format( 'D M j H:i:s Y' ) === $value ||
1361                                                 $ts->format( 'D M  j H:i:s Y' ) === $value
1362                                         ) {
1363                                                 $config = $this->getConfig();
1364                                                 $lastMod = $module->getConditionalRequestData( 'last-modified' );
1365                                                 if ( $lastMod !== null ) {
1366                                                         // Mix in some MediaWiki modification times
1367                                                         $modifiedTimes = [
1368                                                                 'page' => $lastMod,
1369                                                                 'user' => $this->getUser()->getTouched(),
1370                                                                 'epoch' => $config->get( 'CacheEpoch' ),
1371                                                         ];
1372
1373                                                         if ( $config->get( 'UseCdn' ) ) {
1374                                                                 // T46570: the core page itself may not change, but resources might
1375                                                                 $modifiedTimes['sepoch'] = wfTimestamp(
1376                                                                         TS_MW, time() - $config->get( 'CdnMaxAge' )
1377                                                                 );
1378                                                         }
1379                                                         Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this->getOutput() ] );
1380                                                         $lastMod = max( $modifiedTimes );
1381                                                         $return304 = wfTimestamp( TS_MW, $lastMod ) <= $ts->getTimestamp( TS_MW );
1382                                                 }
1383                                         }
1384                                 } catch ( TimestampException $e ) {
1385                                         // Invalid timestamp, ignore it
1386                                 }
1387                         }
1388                 }
1389
1390                 if ( $return304 ) {
1391                         $this->getRequest()->response()->statusHeader( 304 );
1392
1393                         // Avoid outputting the compressed representation of a zero-length body
1394                         Wikimedia\suppressWarnings();
1395                         ini_set( 'zlib.output_compression', 0 );
1396                         Wikimedia\restoreWarnings();
1397                         wfClearOutputBuffers();
1398
1399                         return false;
1400                 }
1401
1402                 return true;
1403         }
1404
1405         /**
1406          * Check for sufficient permissions to execute
1407          * @param ApiBase $module An Api module
1408          */
1409         protected function checkExecutePermissions( $module ) {
1410                 $user = $this->getUser();
1411                 if ( $module->isReadMode() && !User::isEveryoneAllowed( 'read' ) &&
1412                         !$user->isAllowed( 'read' )
1413                 ) {
1414                         $this->dieWithError( 'apierror-readapidenied' );
1415                 }
1416
1417                 if ( $module->isWriteMode() ) {
1418                         if ( !$this->mEnableWrite ) {
1419                                 $this->dieWithError( 'apierror-noapiwrite' );
1420                         } elseif ( !$user->isAllowed( 'writeapi' ) ) {
1421                                 $this->dieWithError( 'apierror-writeapidenied' );
1422                         } elseif ( $this->getRequest()->getHeader( 'Promise-Non-Write-API-Action' ) ) {
1423                                 $this->dieWithError( 'apierror-promised-nonwrite-api' );
1424                         }
1425
1426                         $this->checkReadOnly( $module );
1427                 }
1428
1429                 // Allow extensions to stop execution for arbitrary reasons.
1430                 $message = 'hookaborted';
1431                 if ( !Hooks::run( 'ApiCheckCanExecute', [ $module, $user, &$message ] ) ) {
1432                         $this->dieWithError( $message );
1433                 }
1434         }
1435
1436         /**
1437          * Check if the DB is read-only for this user
1438          * @param ApiBase $module An Api module
1439          */
1440         protected function checkReadOnly( $module ) {
1441                 if ( wfReadOnly() ) {
1442                         $this->dieReadOnly();
1443                 }
1444
1445                 if ( $module->isWriteMode()
1446                         && $this->getUser()->isBot()
1447                         && MediaWikiServices::getInstance()->getDBLoadBalancer()->getServerCount() > 1
1448                 ) {
1449                         $this->checkBotReadOnly();
1450                 }
1451         }
1452
1453         /**
1454          * Check whether we are readonly for bots
1455          */
1456         private function checkBotReadOnly() {
1457                 // Figure out how many servers have passed the lag threshold
1458                 $numLagged = 0;
1459                 $lagLimit = $this->getConfig()->get( 'APIMaxLagThreshold' );
1460                 $laggedServers = [];
1461                 $loadBalancer = MediaWikiServices::getInstance()->getDBLoadBalancer();
1462                 foreach ( $loadBalancer->getLagTimes() as $serverIndex => $lag ) {
1463                         if ( $lag > $lagLimit ) {
1464                                 ++$numLagged;
1465                                 $laggedServers[] = $loadBalancer->getServerName( $serverIndex ) . " ({$lag}s)";
1466                         }
1467                 }
1468
1469                 // If a majority of replica DBs are too lagged then disallow writes
1470                 $replicaCount = $loadBalancer->getServerCount() - 1;
1471                 if ( $numLagged >= ceil( $replicaCount / 2 ) ) {
1472                         $laggedServers = implode( ', ', $laggedServers );
1473                         wfDebugLog(
1474                                 'api-readonly', // Deprecate this channel in favor of api-warning?
1475                                 "Api request failed as read only because the following DBs are lagged: $laggedServers"
1476                         );
1477                         LoggerFactory::getInstance( 'api-warning' )->warning(
1478                                 "Api request failed as read only because the following DBs are lagged: {laggeddbs}", [
1479                                         'laggeddbs' => $laggedServers,
1480                                 ]
1481                         );
1482
1483                         $this->dieWithError(
1484                                 'readonly_lag',
1485                                 'readonly',
1486                                 [ 'readonlyreason' => "Waiting for $numLagged lagged database(s)" ]
1487                         );
1488                 }
1489         }
1490
1491         /**
1492          * Check asserts of the user's rights
1493          * @param array $params
1494          */
1495         protected function checkAsserts( $params ) {
1496                 if ( isset( $params['assert'] ) ) {
1497                         $user = $this->getUser();
1498                         switch ( $params['assert'] ) {
1499                                 case 'user':
1500                                         if ( $user->isAnon() ) {
1501                                                 $this->dieWithError( 'apierror-assertuserfailed' );
1502                                         }
1503                                         break;
1504                                 case 'bot':
1505                                         if ( !$user->isAllowed( 'bot' ) ) {
1506                                                 $this->dieWithError( 'apierror-assertbotfailed' );
1507                                         }
1508                                         break;
1509                         }
1510                 }
1511                 if ( isset( $params['assertuser'] ) ) {
1512                         $assertUser = User::newFromName( $params['assertuser'], false );
1513                         if ( !$assertUser || !$this->getUser()->equals( $assertUser ) ) {
1514                                 $this->dieWithError(
1515                                         [ 'apierror-assertnameduserfailed', wfEscapeWikiText( $params['assertuser'] ) ]
1516                                 );
1517                         }
1518                 }
1519         }
1520
1521         /**
1522          * Check POST for external response and setup result printer
1523          * @param ApiBase $module An Api module
1524          * @param array $params An array with the request parameters
1525          */
1526         protected function setupExternalResponse( $module, $params ) {
1527                 $validMethods = [ 'GET', 'HEAD', 'POST', 'OPTIONS' ];
1528                 $request = $this->getRequest();
1529
1530                 if ( !in_array( $request->getMethod(), $validMethods ) ) {
1531                         $this->dieWithError( 'apierror-invalidmethod', null, null, 405 );
1532                 }
1533
1534                 if ( !$request->wasPosted() && $module->mustBePosted() ) {
1535                         // Module requires POST. GET request might still be allowed
1536                         // if $wgDebugApi is true, otherwise fail.
1537                         $this->dieWithErrorOrDebug( [ 'apierror-mustbeposted', $this->mAction ] );
1538                 }
1539
1540                 // See if custom printer is used
1541                 $this->mPrinter = $module->getCustomPrinter();
1542                 if ( is_null( $this->mPrinter ) ) {
1543                         // Create an appropriate printer
1544                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
1545                 }
1546
1547                 if ( $request->getProtocol() === 'http' && (
1548                         $request->getSession()->shouldForceHTTPS() ||
1549                         ( $this->getUser()->isLoggedIn() &&
1550                                 $this->getUser()->requiresHTTPS() )
1551                 ) ) {
1552                         $this->addDeprecation( 'apiwarn-deprecation-httpsexpected', 'https-expected' );
1553                 }
1554         }
1555
1556         /**
1557          * Execute the actual module, without any error handling
1558          */
1559         protected function executeAction() {
1560                 $params = $this->setupExecuteAction();
1561
1562                 // Check asserts early so e.g. errors in parsing a module's parameters due to being
1563                 // logged out don't override the client's intended "am I logged in?" check.
1564                 $this->checkAsserts( $params );
1565
1566                 $module = $this->setupModule();
1567                 $this->mModule = $module;
1568
1569                 if ( !$this->mInternalMode ) {
1570                         $this->setRequestExpectations( $module );
1571                 }
1572
1573                 $this->checkExecutePermissions( $module );
1574
1575                 if ( !$this->checkMaxLag( $module, $params ) ) {
1576                         return;
1577                 }
1578
1579                 if ( !$this->checkConditionalRequestHeaders( $module ) ) {
1580                         return;
1581                 }
1582
1583                 if ( !$this->mInternalMode ) {
1584                         $this->setupExternalResponse( $module, $params );
1585                 }
1586
1587                 $module->execute();
1588                 Hooks::run( 'APIAfterExecute', [ &$module ] );
1589
1590                 $this->reportUnusedParams();
1591
1592                 if ( !$this->mInternalMode ) {
1593                         MWDebug::appendDebugInfoToApiResult( $this->getContext(), $this->getResult() );
1594
1595                         $this->printResult();
1596                 }
1597         }
1598
1599         /**
1600          * Set database connection, query, and write expectations given this module request
1601          * @param ApiBase $module
1602          */
1603         protected function setRequestExpectations( ApiBase $module ) {
1604                 $limits = $this->getConfig()->get( 'TrxProfilerLimits' );
1605                 $trxProfiler = Profiler::instance()->getTransactionProfiler();
1606                 $trxProfiler->setLogger( LoggerFactory::getInstance( 'DBPerformance' ) );
1607                 if ( $this->getRequest()->hasSafeMethod() ) {
1608                         $trxProfiler->setExpectations( $limits['GET'], __METHOD__ );
1609                 } elseif ( $this->getRequest()->wasPosted() && !$module->isWriteMode() ) {
1610                         $trxProfiler->setExpectations( $limits['POST-nonwrite'], __METHOD__ );
1611                         $this->getRequest()->markAsSafeRequest();
1612                 } else {
1613                         $trxProfiler->setExpectations( $limits['POST'], __METHOD__ );
1614                 }
1615         }
1616
1617         /**
1618          * Log the preceding request
1619          * @param float $time Time in seconds
1620          * @param Exception|Throwable|null $e Exception caught while processing the request
1621          */
1622         protected function logRequest( $time, $e = null ) {
1623                 $request = $this->getRequest();
1624
1625                 $logCtx = [
1626                         // https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/event-schemas/+/master/jsonschema/mediawiki/api/request
1627                         '$schema' => '/mediawiki/api/request/0.0.1',
1628                         'meta' => [
1629                                 'request_id' => WebRequest::getRequestId(),
1630                                 'id' => UIDGenerator::newUUIDv4(),
1631                                 'dt' => wfTimestamp( TS_ISO_8601 ),
1632                                 'domain' => $this->getConfig()->get( 'ServerName' ),
1633                                 // If using the EventBus extension (as intended) with this log channel,
1634                                 // this stream name will map to a Kafka topic.
1635                                 'stream' => 'mediawiki.api-request'
1636                         ],
1637                         'http' => [
1638                                 'method' => $request->getMethod(),
1639                                 'client_ip' => $request->getIP()
1640                         ],
1641                         'database' => WikiMap::getCurrentWikiDbDomain()->getId(),
1642                         'backend_time_ms' => (int)round( $time * 1000 ),
1643                 ];
1644
1645                 // If set, these headers will be logged in http.request_headers.
1646                 $httpRequestHeadersToLog = [ 'accept-language', 'referer', 'user-agent' ];
1647                 foreach ( $httpRequestHeadersToLog as $header ) {
1648                         if ( $request->getHeader( $header ) ) {
1649                                 // Set the header in http.request_headers
1650                                 $logCtx['http']['request_headers'][$header] = $request->getHeader( $header );
1651                         }
1652                 }
1653
1654                 if ( $e ) {
1655                         $logCtx['api_error_codes'] = [];
1656                         foreach ( $this->errorMessagesFromException( $e ) as $msg ) {
1657                                 $logCtx['api_error_codes'][] = $msg->getApiCode();
1658                         }
1659                 }
1660
1661                 // Construct space separated message for 'api' log channel
1662                 $msg = "API {$request->getMethod()} " .
1663                         wfUrlencode( str_replace( ' ', '_', $this->getUser()->getName() ) ) .
1664                         " {$logCtx['http']['client_ip']} " .
1665                         "T={$logCtx['backend_time_ms']}ms";
1666
1667                 $sensitive = array_flip( $this->getSensitiveParams() );
1668                 foreach ( $this->getParamsUsed() as $name ) {
1669                         $value = $request->getVal( $name );
1670                         if ( $value === null ) {
1671                                 continue;
1672                         }
1673
1674                         if ( isset( $sensitive[$name] ) ) {
1675                                 $value = '[redacted]';
1676                                 $encValue = '[redacted]';
1677                         } elseif ( strlen( $value ) > 256 ) {
1678                                 $value = substr( $value, 0, 256 );
1679                                 $encValue = $this->encodeRequestLogValue( $value ) . '[...]';
1680                         } else {
1681                                 $encValue = $this->encodeRequestLogValue( $value );
1682                         }
1683
1684                         $logCtx['params'][$name] = $value;
1685                         $msg .= " {$name}={$encValue}";
1686                 }
1687
1688                 // Log an unstructured message to the api channel.
1689                 wfDebugLog( 'api', $msg, 'private' );
1690
1691                 // The api-request channel a structured data log channel.
1692                 wfDebugLog( 'api-request', '', 'private', $logCtx );
1693         }
1694
1695         /**
1696          * Encode a value in a format suitable for a space-separated log line.
1697          * @param string $s
1698          * @return string
1699          */
1700         protected function encodeRequestLogValue( $s ) {
1701                 static $table;
1702                 if ( !$table ) {
1703                         $chars = ';@$!*(),/:';
1704                         $numChars = strlen( $chars );
1705                         for ( $i = 0; $i < $numChars; $i++ ) {
1706                                 $table[rawurlencode( $chars[$i] )] = $chars[$i];
1707                         }
1708                 }
1709
1710                 return strtr( rawurlencode( $s ), $table );
1711         }
1712
1713         /**
1714          * Get the request parameters used in the course of the preceding execute() request
1715          * @return array
1716          */
1717         protected function getParamsUsed() {
1718                 return array_keys( $this->mParamsUsed );
1719         }
1720
1721         /**
1722          * Mark parameters as used
1723          * @param string|string[] $params
1724          */
1725         public function markParamsUsed( $params ) {
1726                 $this->mParamsUsed += array_fill_keys( (array)$params, true );
1727         }
1728
1729         /**
1730          * Get the request parameters that should be considered sensitive
1731          * @since 1.29
1732          * @return array
1733          */
1734         protected function getSensitiveParams() {
1735                 return array_keys( $this->mParamsSensitive );
1736         }
1737
1738         /**
1739          * Mark parameters as sensitive
1740          * @since 1.29
1741          * @param string|string[] $params
1742          */
1743         public function markParamsSensitive( $params ) {
1744                 $this->mParamsSensitive += array_fill_keys( (array)$params, true );
1745         }
1746
1747         /**
1748          * Get a request value, and register the fact that it was used, for logging.
1749          * @param string $name
1750          * @param string|null $default
1751          * @return string|null
1752          */
1753         public function getVal( $name, $default = null ) {
1754                 $this->mParamsUsed[$name] = true;
1755
1756                 $ret = $this->getRequest()->getVal( $name );
1757                 if ( $ret === null ) {
1758                         if ( $this->getRequest()->getArray( $name ) !== null ) {
1759                                 // See T12262 for why we don't just implode( '|', ... ) the
1760                                 // array.
1761                                 $this->addWarning( [ 'apiwarn-unsupportedarray', $name ] );
1762                         }
1763                         $ret = $default;
1764                 }
1765                 return $ret;
1766         }
1767
1768         /**
1769          * Get a boolean request value, and register the fact that the parameter
1770          * was used, for logging.
1771          * @param string $name
1772          * @return bool
1773          */
1774         public function getCheck( $name ) {
1775                 return $this->getVal( $name, null ) !== null;
1776         }
1777
1778         /**
1779          * Get a request upload, and register the fact that it was used, for logging.
1780          *
1781          * @since 1.21
1782          * @param string $name Parameter name
1783          * @return WebRequestUpload
1784          */
1785         public function getUpload( $name ) {
1786                 $this->mParamsUsed[$name] = true;
1787
1788                 return $this->getRequest()->getUpload( $name );
1789         }
1790
1791         /**
1792          * Report unused parameters, so the client gets a hint in case it gave us parameters we don't know,
1793          * for example in case of spelling mistakes or a missing 'g' prefix for generators.
1794          */
1795         protected function reportUnusedParams() {
1796                 $paramsUsed = $this->getParamsUsed();
1797                 $allParams = $this->getRequest()->getValueNames();
1798
1799                 if ( !$this->mInternalMode ) {
1800                         // Printer has not yet executed; don't warn that its parameters are unused
1801                         $printerParams = $this->mPrinter->encodeParamName(
1802                                 array_keys( $this->mPrinter->getFinalParams() ?: [] )
1803                         );
1804                         $unusedParams = array_diff( $allParams, $paramsUsed, $printerParams );
1805                 } else {
1806                         $unusedParams = array_diff( $allParams, $paramsUsed );
1807                 }
1808
1809                 if ( count( $unusedParams ) ) {
1810                         $this->addWarning( [
1811                                 'apierror-unrecognizedparams',
1812                                 Message::listParam( array_map( 'wfEscapeWikiText', $unusedParams ), 'comma' ),
1813                                 count( $unusedParams )
1814                         ] );
1815                 }
1816         }
1817
1818         /**
1819          * Print results using the current printer
1820          *
1821          * @param int $httpCode HTTP status code, or 0 to not change
1822          */
1823         protected function printResult( $httpCode = 0 ) {
1824                 if ( $this->getConfig()->get( 'DebugAPI' ) !== false ) {
1825                         $this->addWarning( 'apiwarn-wgdebugapi' );
1826                 }
1827
1828                 $printer = $this->mPrinter;
1829                 $printer->initPrinter( false );
1830                 if ( $httpCode ) {
1831                         $printer->setHttpStatus( $httpCode );
1832                 }
1833                 $printer->execute();
1834                 $printer->closePrinter();
1835         }
1836
1837         /**
1838          * @return bool
1839          */
1840         public function isReadMode() {
1841                 return false;
1842         }
1843
1844         /**
1845          * See ApiBase for description.
1846          *
1847          * @return array
1848          */
1849         public function getAllowedParams() {
1850                 return [
1851                         'action' => [
1852                                 ApiBase::PARAM_DFLT => 'help',
1853                                 ApiBase::PARAM_TYPE => 'submodule',
1854                         ],
1855                         'format' => [
1856                                 ApiBase::PARAM_DFLT => self::API_DEFAULT_FORMAT,
1857                                 ApiBase::PARAM_TYPE => 'submodule',
1858                         ],
1859                         'maxlag' => [
1860                                 ApiBase::PARAM_TYPE => 'integer'
1861                         ],
1862                         'smaxage' => [
1863                                 ApiBase::PARAM_TYPE => 'integer',
1864                                 ApiBase::PARAM_DFLT => 0
1865                         ],
1866                         'maxage' => [
1867                                 ApiBase::PARAM_TYPE => 'integer',
1868                                 ApiBase::PARAM_DFLT => 0
1869                         ],
1870                         'assert' => [
1871                                 ApiBase::PARAM_TYPE => [ 'user', 'bot' ]
1872                         ],
1873                         'assertuser' => [
1874                                 ApiBase::PARAM_TYPE => 'user',
1875                         ],
1876                         'requestid' => null,
1877                         'servedby' => false,
1878                         'curtimestamp' => false,
1879                         'responselanginfo' => false,
1880                         'origin' => null,
1881                         'uselang' => [
1882                                 ApiBase::PARAM_DFLT => self::API_DEFAULT_USELANG,
1883                         ],
1884                         'errorformat' => [
1885                                 ApiBase::PARAM_TYPE => [ 'plaintext', 'wikitext', 'html', 'raw', 'none', 'bc' ],
1886                                 ApiBase::PARAM_DFLT => 'bc',
1887                         ],
1888                         'errorlang' => [
1889                                 ApiBase::PARAM_DFLT => 'uselang',
1890                         ],
1891                         'errorsuselocal' => [
1892                                 ApiBase::PARAM_DFLT => false,
1893                         ],
1894                 ];
1895         }
1896
1897         /** @inheritDoc */
1898         protected function getExamplesMessages() {
1899                 return [
1900                         'action=help'
1901                                 => 'apihelp-help-example-main',
1902                         'action=help&recursivesubmodules=1'
1903                                 => 'apihelp-help-example-recursive',
1904                 ];
1905         }
1906
1907         public function modifyHelp( array &$help, array $options, array &$tocData ) {
1908                 // Wish PHP had an "array_insert_before". Instead, we have to manually
1909                 // reindex the array to get 'permissions' in the right place.
1910                 $oldHelp = $help;
1911                 $help = [];
1912                 foreach ( $oldHelp as $k => $v ) {
1913                         if ( $k === 'submodules' ) {
1914                                 $help['permissions'] = '';
1915                         }
1916                         $help[$k] = $v;
1917                 }
1918                 $help['datatypes'] = '';
1919                 $help['templatedparams'] = '';
1920                 $help['credits'] = '';
1921
1922                 // Fill 'permissions'
1923                 $help['permissions'] .= Html::openElement( 'div',
1924                         [ 'class' => 'apihelp-block apihelp-permissions' ] );
1925                 $m = $this->msg( 'api-help-permissions' );
1926                 if ( !$m->isDisabled() ) {
1927                         $help['permissions'] .= Html::rawElement( 'div', [ 'class' => 'apihelp-block-head' ],
1928                                 $m->numParams( count( self::$mRights ) )->parse()
1929                         );
1930                 }
1931                 $help['permissions'] .= Html::openElement( 'dl' );
1932                 foreach ( self::$mRights as $right => $rightMsg ) {
1933                         $help['permissions'] .= Html::element( 'dt', null, $right );
1934
1935                         $rightMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )->parse();
1936                         $help['permissions'] .= Html::rawElement( 'dd', null, $rightMsg );
1937
1938                         $groups = array_map( function ( $group ) {
1939                                 return $group == '*' ? 'all' : $group;
1940                         }, User::getGroupsWithPermission( $right ) );
1941
1942                         $help['permissions'] .= Html::rawElement( 'dd', null,
1943                                 $this->msg( 'api-help-permissions-granted-to' )
1944                                         ->numParams( count( $groups ) )
1945                                         ->params( Message::listParam( $groups ) )
1946                                         ->parse()
1947                         );
1948                 }
1949                 $help['permissions'] .= Html::closeElement( 'dl' );
1950                 $help['permissions'] .= Html::closeElement( 'div' );
1951
1952                 // Fill 'datatypes', 'templatedparams', and 'credits', if applicable
1953                 if ( empty( $options['nolead'] ) ) {
1954                         $level = $options['headerlevel'];
1955                         $tocnumber = &$options['tocnumber'];
1956
1957                         $header = $this->msg( 'api-help-datatypes-header' )->parse();
1958
1959                         $id = Sanitizer::escapeIdForAttribute( 'main/datatypes', Sanitizer::ID_PRIMARY );
1960                         $idFallback = Sanitizer::escapeIdForAttribute( 'main/datatypes', Sanitizer::ID_FALLBACK );
1961                         $headline = Linker::makeHeadline( min( 6, $level ),
1962                                 ' class="apihelp-header">',
1963                                 $id,
1964                                 $header,
1965                                 '',
1966                                 $idFallback
1967                         );
1968                         // Ensure we have a sane anchor
1969                         if ( $id !== 'main/datatypes' && $idFallback !== 'main/datatypes' ) {
1970                                 $headline = '<div id="main/datatypes"></div>' . $headline;
1971                         }
1972                         $help['datatypes'] .= $headline;
1973                         $help['datatypes'] .= $this->msg( 'api-help-datatypes' )->parseAsBlock();
1974                         if ( !isset( $tocData['main/datatypes'] ) ) {
1975                                 $tocnumber[$level]++;
1976                                 $tocData['main/datatypes'] = [
1977                                         'toclevel' => count( $tocnumber ),
1978                                         'level' => $level,
1979                                         'anchor' => 'main/datatypes',
1980                                         'line' => $header,
1981                                         'number' => implode( '.', $tocnumber ),
1982                                         'index' => false,
1983                                 ];
1984                         }
1985
1986                         $header = $this->msg( 'api-help-templatedparams-header' )->parse();
1987
1988                         $id = Sanitizer::escapeIdForAttribute( 'main/templatedparams', Sanitizer::ID_PRIMARY );
1989                         $idFallback = Sanitizer::escapeIdForAttribute( 'main/templatedparams', Sanitizer::ID_FALLBACK );
1990                         $headline = Linker::makeHeadline( min( 6, $level ),
1991                                 ' class="apihelp-header">',
1992                                 $id,
1993                                 $header,
1994                                 '',
1995                                 $idFallback
1996                         );
1997                         // Ensure we have a sane anchor
1998                         if ( $id !== 'main/templatedparams' && $idFallback !== 'main/templatedparams' ) {
1999                                 $headline = '<div id="main/templatedparams"></div>' . $headline;
2000                         }
2001                         $help['templatedparams'] .= $headline;
2002                         $help['templatedparams'] .= $this->msg( 'api-help-templatedparams' )->parseAsBlock();
2003                         if ( !isset( $tocData['main/templatedparams'] ) ) {
2004                                 $tocnumber[$level]++;
2005                                 $tocData['main/templatedparams'] = [
2006                                         'toclevel' => count( $tocnumber ),
2007                                         'level' => $level,
2008                                         'anchor' => 'main/templatedparams',
2009                                         'line' => $header,
2010                                         'number' => implode( '.', $tocnumber ),
2011                                         'index' => false,
2012                                 ];
2013                         }
2014
2015                         $header = $this->msg( 'api-credits-header' )->parse();
2016                         $id = Sanitizer::escapeIdForAttribute( 'main/credits', Sanitizer::ID_PRIMARY );
2017                         $idFallback = Sanitizer::escapeIdForAttribute( 'main/credits', Sanitizer::ID_FALLBACK );
2018                         $headline = Linker::makeHeadline( min( 6, $level ),
2019                                 ' class="apihelp-header">',
2020                                 $id,
2021                                 $header,
2022                                 '',
2023                                 $idFallback
2024                         );
2025                         // Ensure we have a sane anchor
2026                         if ( $id !== 'main/credits' && $idFallback !== 'main/credits' ) {
2027                                 $headline = '<div id="main/credits"></div>' . $headline;
2028                         }
2029                         $help['credits'] .= $headline;
2030                         $help['credits'] .= $this->msg( 'api-credits' )->useDatabase( false )->parseAsBlock();
2031                         if ( !isset( $tocData['main/credits'] ) ) {
2032                                 $tocnumber[$level]++;
2033                                 $tocData['main/credits'] = [
2034                                         'toclevel' => count( $tocnumber ),
2035                                         'level' => $level,
2036                                         'anchor' => 'main/credits',
2037                                         'line' => $header,
2038                                         'number' => implode( '.', $tocnumber ),
2039                                         'index' => false,
2040                                 ];
2041                         }
2042                 }
2043         }
2044
2045         private $mCanApiHighLimits = null;
2046
2047         /**
2048          * Check whether the current user is allowed to use high limits
2049          * @return bool
2050          */
2051         public function canApiHighLimits() {
2052                 if ( !isset( $this->mCanApiHighLimits ) ) {
2053                         $this->mCanApiHighLimits = $this->getUser()->isAllowed( 'apihighlimits' );
2054                 }
2055
2056                 return $this->mCanApiHighLimits;
2057         }
2058
2059         /**
2060          * Overrides to return this instance's module manager.
2061          * @return ApiModuleManager
2062          */
2063         public function getModuleManager() {
2064                 return $this->mModuleMgr;
2065         }
2066
2067         /**
2068          * Fetches the user agent used for this request
2069          *
2070          * The value will be the combination of the 'Api-User-Agent' header (if
2071          * any) and the standard User-Agent header (if any).
2072          *
2073          * @return string
2074          */
2075         public function getUserAgent() {
2076                 return trim(
2077                         $this->getRequest()->getHeader( 'Api-user-agent' ) . ' ' .
2078                         $this->getRequest()->getHeader( 'User-agent' )
2079                 );
2080         }
2081 }
2082
2083 /**
2084  * For really cool vim folding this needs to be at the end:
2085  * vim: foldmarker=@{,@} foldmethod=marker
2086  */