includes/api/ApiMain.php

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