includes/api/ApiMain.php

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