includes/api/ApiMain.php

   1 <?php
   2 /**
   3  *
   4  *
   5  * Created on Sep 4, 2006
   6  *
   7  * Copyright © 2006 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  22  * http://www.gnu.org/copyleft/gpl.html
  23  *
  24  * @file
  25  * @defgroup API API
  26  */
  27
  28 /**
  29  * This is the main API class, used for both external and internal processing.
  30  * When executed, it will create the requested formatter object,
  31  * instantiate and execute an object associated with the needed action,
  32  * and use formatter to print results.
  33  * In case of an exception, an error message will be printed using the same formatter.
  34  *
  35  * To use API from another application, run it using FauxRequest object, in which
  36  * case any internal exceptions will not be handled but passed up to the caller.
  37  * After successful execution, use getResult() for the resulting data.
  38  *
  39  * @ingroup API
  40  */
  41 class ApiMain extends ApiBase {
  42         /**
  43          * When no format parameter is given, this format will be used
  44          */
  45         const API_DEFAULT_FORMAT = 'jsonfm';
  46
  47         /**
  48          * List of available modules: action name => module class
  49          */
  50         private static $Modules = [
  51                 'login' => 'ApiLogin',
  52                 'clientlogin' => 'ApiClientLogin',
  53                 'logout' => 'ApiLogout',
  54                 'createaccount' => 'ApiAMCreateAccount',
  55                 'linkaccount' => 'ApiLinkAccount',
  56                 'unlinkaccount' => 'ApiRemoveAuthenticationData',
  57                 'changeauthenticationdata' => 'ApiChangeAuthenticationData',
  58                 'removeauthenticationdata' => 'ApiRemoveAuthenticationData',
  59                 'resetpassword' => 'ApiResetPassword',
  60                 'query' => 'ApiQuery',
  61                 'expandtemplates' => 'ApiExpandTemplates',
  62                 'parse' => 'ApiParse',
  63                 'stashedit' => 'ApiStashEdit',
  64                 'opensearch' => 'ApiOpenSearch',
  65                 'feedcontributions' => 'ApiFeedContributions',
  66                 'feedrecentchanges' => 'ApiFeedRecentChanges',
  67                 'feedwatchlist' => 'ApiFeedWatchlist',
  68                 'help' => 'ApiHelp',
  69                 'paraminfo' => 'ApiParamInfo',
  70                 'rsd' => 'ApiRsd',
  71                 'compare' => 'ApiComparePages',
  72                 'tokens' => 'ApiTokens',
  73                 'checktoken' => 'ApiCheckToken',
  74
  75                 // Write modules
  76                 'purge' => 'ApiPurge',
  77                 'setnotificationtimestamp' => 'ApiSetNotificationTimestamp',
  78                 'rollback' => 'ApiRollback',
  79                 'delete' => 'ApiDelete',
  80                 'undelete' => 'ApiUndelete',
  81                 'protect' => 'ApiProtect',
  82                 'block' => 'ApiBlock',
  83                 'unblock' => 'ApiUnblock',
  84                 'move' => 'ApiMove',
  85                 'edit' => 'ApiEditPage',
  86                 'upload' => 'ApiUpload',
  87                 'filerevert' => 'ApiFileRevert',
  88                 'emailuser' => 'ApiEmailUser',
  89                 'watch' => 'ApiWatch',
  90                 'patrol' => 'ApiPatrol',
  91                 'import' => 'ApiImport',
  92                 'clearhasmsg' => 'ApiClearHasMsg',
  93                 'userrights' => 'ApiUserrights',
  94                 'options' => 'ApiOptions',
  95                 'imagerotate' => 'ApiImageRotate',
  96                 'revisiondelete' => 'ApiRevisionDelete',
  97                 'managetags' => 'ApiManageTags',
  98                 'tag' => 'ApiTag',
  99                 'mergehistory' => 'ApiMergeHistory',
 100         ];
 101
 102         /**
 103          * List of available formats: format name => format class
 104          */
 105         private static $Formats = [
 106                 'json' => 'ApiFormatJson',
 107                 'jsonfm' => 'ApiFormatJson',
 108                 'php' => 'ApiFormatPhp',
 109                 'phpfm' => 'ApiFormatPhp',
 110                 'xml' => 'ApiFormatXml',
 111                 'xmlfm' => 'ApiFormatXml',
 112                 'rawfm' => 'ApiFormatJson',
 113                 'none' => 'ApiFormatNone',
 114         ];
 115
 116         // @codingStandardsIgnoreStart String contenation on "msg" not allowed to break long line
 117         /**
 118          * List of user roles that are specifically relevant to the API.
 119          * array( 'right' => array ( 'msg'    => 'Some message with a $1',
 120          *                           'params' => array ( $someVarToSubst ) ),
 121          *                          );
 122          */
 123         private static $mRights = [
 124                 'writeapi' => [
 125                         'msg' => 'right-writeapi',
 126                         'params' => []
 127                 ],
 128                 'apihighlimits' => [
 129                         'msg' => 'api-help-right-apihighlimits',
 130                         'params' => [ ApiBase::LIMIT_SML2, ApiBase::LIMIT_BIG2 ]
 131                 ]
 132         ];
 133         // @codingStandardsIgnoreEnd
 134
 135         /**
 136          * @var ApiFormatBase
 137          */
 138         private $mPrinter;
 139
 140         private $mModuleMgr, $mResult, $mErrorFormatter, $mContinuationManager;
 141         private $mAction;
 142         private $mEnableWrite;
 143         private $mInternalMode, $mSquidMaxage;
 144         /** @var ApiBase */
 145         private $mModule;
 146
 147         private $mCacheMode = 'private';
 148         private $mCacheControl = [];
 149         private $mParamsUsed = [];
 150
 151         /** @var bool|null Cached return value from self::lacksSameOriginSecurity() */
 152         private $lacksSameOriginSecurity = null;
 153
 154         /**
 155          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 156          *
 157          * @param IContextSource|WebRequest $context If this is an instance of
 158          *    FauxRequest, errors are thrown and no printing occurs
 159          * @param bool $enableWrite Should be set to true if the api may modify data
 160          */
 161         public function __construct( $context = null, $enableWrite = false ) {
 162                 if ( $context === null ) {
 163                         $context = RequestContext::getMain();
 164                 } elseif ( $context instanceof WebRequest ) {
 165                         // BC for pre-1.19
 166                         $request = $context;
 167                         $context = RequestContext::getMain();
 168                 }
 169                 // We set a derivative context so we can change stuff later
 170                 $this->setContext( new DerivativeContext( $context ) );
 171
 172                 if ( isset( $request ) ) {
 173                         $this->getContext()->setRequest( $request );
 174                 }
 175
 176                 $this->mInternalMode = ( $this->getRequest() instanceof FauxRequest );
 177
 178                 // Special handling for the main module: $parent === $this
 179                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 180
 181                 if ( !$this->mInternalMode ) {
 182                         // Impose module restrictions.
 183                         // If the current user cannot read,
 184                         // Remove all modules other than login
 185                         global $wgUser;
 186
 187                         if ( $this->lacksSameOriginSecurity() ) {
 188                                 // If we're in a mode that breaks the same-origin policy, strip
 189                                 // user credentials for security.
 190                                 wfDebug( "API: stripping user credentials when the same-origin policy is not applied\n" );
 191                                 $wgUser = new User();
 192                                 $this->getContext()->setUser( $wgUser );
 193                         }
 194                 }
 195
 196                 $uselang = $this->getParameter( 'uselang' );
 197                 if ( $uselang === 'user' ) {
 198                         // Assume the parent context is going to return the user language
 199                         // for uselang=user (see T85635).
 200                 } else {
 201                         if ( $uselang === 'content' ) {
 202                                 global $wgContLang;
 203                                 $uselang = $wgContLang->getCode();
 204                         }
 205                         $code = RequestContext::sanitizeLangCode( $uselang );
 206                         $this->getContext()->setLanguage( $code );
 207                         if ( !$this->mInternalMode ) {
 208                                 global $wgLang;
 209                                 $wgLang = $this->getContext()->getLanguage();
 210                                 RequestContext::getMain()->setLanguage( $wgLang );
 211                         }
 212                 }
 213
 214                 $config = $this->getConfig();
 215                 $this->mModuleMgr = new ApiModuleManager( $this );
 216                 $this->mModuleMgr->addModules( self::$Modules, 'action' );
 217                 $this->mModuleMgr->addModules( $config->get( 'APIModules' ), 'action' );
 218                 $this->mModuleMgr->addModules( self::$Formats, 'format' );
 219                 $this->mModuleMgr->addModules( $config->get( 'APIFormatModules' ), 'format' );
 220
 221                 Hooks::run( 'ApiMain::moduleManager', [ $this->mModuleMgr ] );
 222
 223                 $this->mResult = new ApiResult( $this->getConfig()->get( 'APIMaxResultSize' ) );
 224                 $this->mErrorFormatter = new ApiErrorFormatter_BackCompat( $this->mResult );
 225                 $this->mResult->setErrorFormatter( $this->mErrorFormatter );
 226                 $this->mResult->setMainForContinuation( $this );
 227                 $this->mContinuationManager = null;
 228                 $this->mEnableWrite = $enableWrite;
 229
 230                 $this->mSquidMaxage = -1; // flag for executeActionWithErrorHandling()
 231                 $this->mCommit = false;
 232         }
 233
 234         /**
 235          * Return true if the API was started by other PHP code using FauxRequest
 236          * @return bool
 237          */
 238         public function isInternalMode() {
 239                 return $this->mInternalMode;
 240         }
 241
 242         /**
 243          * Get the ApiResult object associated with current request
 244          *
 245          * @return ApiResult
 246          */
 247         public function getResult() {
 248                 return $this->mResult;
 249         }
 250
 251         /**
 252          * Get the security flag for the current request
 253          * @return bool
 254          */
 255         public function lacksSameOriginSecurity() {
 256                 if ( $this->lacksSameOriginSecurity !== null ) {
 257                         return $this->lacksSameOriginSecurity;
 258                 }
 259
 260                 $request = $this->getRequest();
 261
 262                 // JSONP mode
 263                 if ( $request->getVal( 'callback' ) !== null ) {
 264                         $this->lacksSameOriginSecurity = true;
 265                         return true;
 266                 }
 267
 268                 // Header to be used from XMLHTTPRequest when the request might
 269                 // otherwise be used for XSS.
 270                 if ( $request->getHeader( 'Treat-as-Untrusted' ) !== false ) {
 271                         $this->lacksSameOriginSecurity = true;
 272                         return true;
 273                 }
 274
 275                 // Allow extensions to override.
 276                 $this->lacksSameOriginSecurity = !Hooks::run( 'RequestHasSameOriginSecurity', [ $request ] );
 277                 return $this->lacksSameOriginSecurity;
 278         }
 279
 280         /**
 281          * Get the ApiErrorFormatter object associated with current request
 282          * @return ApiErrorFormatter
 283          */
 284         public function getErrorFormatter() {
 285                 return $this->mErrorFormatter;
 286         }
 287
 288         /**
 289          * Get the continuation manager
 290          * @return ApiContinuationManager|null
 291          */
 292         public function getContinuationManager() {
 293                 return $this->mContinuationManager;
 294         }
 295
 296         /**
 297          * Set the continuation manager
 298          * @param ApiContinuationManager|null
 299          */
 300         public function setContinuationManager( $manager ) {
 301                 if ( $manager !== null ) {
 302                         if ( !$manager instanceof ApiContinuationManager ) {
 303                                 throw new InvalidArgumentException( __METHOD__ . ': Was passed ' .
 304                                         is_object( $manager ) ? get_class( $manager ) : gettype( $manager )
 305                                 );
 306                         }
 307                         if ( $this->mContinuationManager !== null ) {
 308                                 throw new UnexpectedValueException(
 309                                         __METHOD__ . ': tried to set manager from ' . $manager->getSource() .
 310                                         ' when a manager is already set from ' . $this->mContinuationManager->getSource()
 311                                 );
 312                         }
 313                 }
 314                 $this->mContinuationManager = $manager;
 315         }
 316
 317         /**
 318          * Get the API module object. Only works after executeAction()
 319          *
 320          * @return ApiBase
 321          */
 322         public function getModule() {
 323                 return $this->mModule;
 324         }
 325
 326         /**
 327          * Get the result formatter object. Only works after setupExecuteAction()
 328          *
 329          * @return ApiFormatBase
 330          */
 331         public function getPrinter() {
 332                 return $this->mPrinter;
 333         }
 334
 335         /**
 336          * Set how long the response should be cached.
 337          *
 338          * @param int $maxage
 339          */
 340         public function setCacheMaxAge( $maxage ) {
 341                 $this->setCacheControl( [
 342                         'max-age' => $maxage,
 343                         's-maxage' => $maxage
 344                 ] );
 345         }
 346
 347         /**
 348          * Set the type of caching headers which will be sent.
 349          *
 350          * @param string $mode One of:
 351          *    - 'public':     Cache this object in public caches, if the maxage or smaxage
 352          *         parameter is set, or if setCacheMaxAge() was called. If a maximum age is
 353          *         not provided by any of these means, the object will be private.
 354          *    - 'private':    Cache this object only in private client-side caches.
 355          *    - 'anon-public-user-private': Make this object cacheable for logged-out
 356          *         users, but private for logged-in users. IMPORTANT: If this is set, it must be
 357          *         set consistently for a given URL, it cannot be set differently depending on
 358          *         things like the contents of the database, or whether the user is logged in.
 359          *
 360          *  If the wiki does not allow anonymous users to read it, the mode set here
 361          *  will be ignored, and private caching headers will always be sent. In other words,
 362          *  the "public" mode is equivalent to saying that the data sent is as public as a page
 363          *  view.
 364          *
 365          *  For user-dependent data, the private mode should generally be used. The
 366          *  anon-public-user-private mode should only be used where there is a particularly
 367          *  good performance reason for caching the anonymous response, but where the
 368          *  response to logged-in users may differ, or may contain private data.
 369          *
 370          *  If this function is never called, then the default will be the private mode.
 371          */
 372         public function setCacheMode( $mode ) {
 373                 if ( !in_array( $mode, [ 'private', 'public', 'anon-public-user-private' ] ) ) {
 374                         wfDebug( __METHOD__ . ": unrecognised cache mode \"$mode\"\n" );
 375
 376                         // Ignore for forwards-compatibility
 377                         return;
 378                 }
 379
 380                 if ( !User::isEveryoneAllowed( 'read' ) ) {
 381                         // Private wiki, only private headers
 382                         if ( $mode !== 'private' ) {
 383                                 wfDebug( __METHOD__ . ": ignoring request for $mode cache mode, private wiki\n" );
 384
 385                                 return;
 386                         }
 387                 }
 388
 389                 if ( $mode === 'public' && $this->getParameter( 'uselang' ) === 'user' ) {
 390                         // User language is used for i18n, so we don't want to publicly
 391                         // cache. Anons are ok, because if they have non-default language
 392                         // then there's an appropriate Vary header set by whatever set
 393                         // their non-default language.
 394                         wfDebug( __METHOD__ . ": downgrading cache mode 'public' to " .
 395                                 "'anon-public-user-private' due to uselang=user\n" );
 396                         $mode = 'anon-public-user-private';
 397                 }
 398
 399                 wfDebug( __METHOD__ . ": setting cache mode $mode\n" );
 400                 $this->mCacheMode = $mode;
 401         }
 402
 403         /**
 404          * Set directives (key/value pairs) for the Cache-Control header.
 405          * Boolean values will be formatted as such, by including or omitting
 406          * without an equals sign.
 407          *
 408          * Cache control values set here will only be used if the cache mode is not
 409          * private, see setCacheMode().
 410          *
 411          * @param array $directives
 412          */
 413         public function setCacheControl( $directives ) {
 414                 $this->mCacheControl = $directives + $this->mCacheControl;
 415         }
 416
 417         /**
 418          * Create an instance of an output formatter by its name
 419          *
 420          * @param string $format
 421          *
 422          * @return ApiFormatBase
 423          */
 424         public function createPrinterByName( $format ) {
 425                 $printer = $this->mModuleMgr->getModule( $format, 'format' );
 426                 if ( $printer === null ) {
 427                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 428                 }
 429
 430                 return $printer;
 431         }
 432
 433         /**
 434          * Execute api request. Any errors will be handled if the API was called by the remote client.
 435          */
 436         public function execute() {
 437                 if ( $this->mInternalMode ) {
 438                         $this->executeAction();
 439                 } else {
 440                         $this->executeActionWithErrorHandling();
 441                 }
 442         }
 443
 444         /**
 445          * Execute an action, and in case of an error, erase whatever partial results
 446          * have been accumulated, and replace it with an error message and a help screen.
 447          */
 448         protected function executeActionWithErrorHandling() {
 449                 // Verify the CORS header before executing the action
 450                 if ( !$this->handleCORS() ) {
 451                         // handleCORS() has sent a 403, abort
 452                         return;
 453                 }
 454
 455                 // Exit here if the request method was OPTIONS
 456                 // (assume there will be a followup GET or POST)
 457                 if ( $this->getRequest()->getMethod() === 'OPTIONS' ) {
 458                         return;
 459                 }
 460
 461                 // In case an error occurs during data output,
 462                 // clear the output buffer and print just the error information
 463                 $obLevel = ob_get_level();
 464                 ob_start();
 465
 466                 $t = microtime( true );
 467                 $isError = false;
 468                 try {
 469                         $this->executeAction();
 470                         $runTime = microtime( true ) - $t;
 471                         $this->logRequest( $runTime );
 472                         if ( $this->mModule->isWriteMode() && $this->getRequest()->wasPosted() ) {
 473                                 $this->getStats()->timing(
 474                                         'api.' . $this->getModuleName() . '.executeTiming', 1000 * $runTime );
 475                         }
 476                 } catch ( Exception $e ) {
 477                         $this->handleException( $e );
 478                         $this->logRequest( microtime( true ) - $t, $e );
 479                         $isError = true;
 480                 }
 481
 482                 // Commit DBs and send any related cookies and headers
 483                 MediaWiki::preOutputCommit( $this->getContext() );
 484
 485                 // Send cache headers after any code which might generate an error, to
 486                 // avoid sending public cache headers for errors.
 487                 $this->sendCacheHeaders( $isError );
 488
 489                 // Executing the action might have already messed with the output
 490                 // buffers.
 491                 while ( ob_get_level() > $obLevel ) {
 492                         ob_end_flush();
 493                 }
 494         }
 495
 496         /**
 497          * Handle an exception as an API response
 498          *
 499          * @since 1.23
 500          * @param Exception $e
 501          */
 502         protected function handleException( Exception $e ) {
 503                 // Bug 63145: Rollback any open database transactions
 504                 if ( !( $e instanceof UsageException ) ) {
 505                         // UsageExceptions are intentional, so don't rollback if that's the case
 506                         try {
 507                                 MWExceptionHandler::rollbackMasterChangesAndLog( $e );
 508                         } catch ( DBError $e2 ) {
 509                                 // Rollback threw an exception too. Log it, but don't interrupt
 510                                 // our regularly scheduled exception handling.
 511                                 MWExceptionHandler::logException( $e2 );
 512                         }
 513                 }
 514
 515                 // Allow extra cleanup and logging
 516                 Hooks::run( 'ApiMain::onException', [ $this, $e ] );
 517
 518                 // Log it
 519                 if ( !( $e instanceof UsageException ) ) {
 520                         MWExceptionHandler::logException( $e );
 521                 }
 522
 523                 // Handle any kind of exception by outputting properly formatted error message.
 524                 // If this fails, an unhandled exception should be thrown so that global error
 525                 // handler will process and log it.
 526
 527                 $errCode = $this->substituteResultWithError( $e );
 528
 529                 // Error results should not be cached
 530                 $this->setCacheMode( 'private' );
 531
 532                 $response = $this->getRequest()->response();
 533                 $headerStr = 'MediaWiki-API-Error: ' . $errCode;
 534                 if ( $e->getCode() === 0 ) {
 535                         $response->header( $headerStr );
 536                 } else {
 537                         $response->header( $headerStr, true, $e->getCode() );
 538                 }
 539
 540                 // Reset and print just the error message
 541                 ob_clean();
 542
 543                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 544                 $this->createErrorPrinter();
 545
 546                 try {
 547                         $this->printResult( true );
 548                 } catch ( UsageException $ex ) {
 549                         // The error printer itself is failing. Try suppressing its request
 550                         // parameters and redo.
 551                         $this->setWarning(
 552                                 'Error printer failed (will retry without params): ' . $ex->getMessage()
 553                         );
 554                         $this->mPrinter = null;
 555                         $this->createErrorPrinter();
 556                         $this->mPrinter->forceDefaultParams();
 557                         $this->printResult( true );
 558                 }
 559         }
 560
 561         /**
 562          * Handle an exception from the ApiBeforeMain hook.
 563          *
 564          * This tries to print the exception as an API response, to be more
 565          * friendly to clients. If it fails, it will rethrow the exception.
 566          *
 567          * @since 1.23
 568          * @param Exception $e
 569          * @throws Exception
 570          */
 571         public static function handleApiBeforeMainException( Exception $e ) {
 572                 ob_start();
 573
 574                 try {
 575                         $main = new self( RequestContext::getMain(), false );
 576                         $main->handleException( $e );
 577                         $main->logRequest( 0, $e );
 578                 } catch ( Exception $e2 ) {
 579                         // Nope, even that didn't work. Punt.
 580                         throw $e;
 581                 }
 582
 583                 // Reset cache headers
 584                 $main->sendCacheHeaders( true );
 585
 586                 ob_end_flush();
 587         }
 588
 589         /**
 590          * Check the &origin= query parameter against the Origin: HTTP header and respond appropriately.
 591          *
 592          * If no origin parameter is present, nothing happens.
 593          * If an origin parameter is present but doesn't match the Origin header, a 403 status code
 594          * is set and false is returned.
 595          * If the parameter and the header do match, the header is checked against $wgCrossSiteAJAXdomains
 596          * and $wgCrossSiteAJAXdomainExceptions, and if the origin qualifies, the appropriate CORS
 597          * headers are set.
 598          * http://www.w3.org/TR/cors/#resource-requests
 599          * http://www.w3.org/TR/cors/#resource-preflight-requests
 600          *
 601          * @return bool False if the caller should abort (403 case), true otherwise (all other cases)
 602          */
 603         protected function handleCORS() {
 604                 $originParam = $this->getParameter( 'origin' ); // defaults to null
 605                 if ( $originParam === null ) {
 606                         // No origin parameter, nothing to do
 607                         return true;
 608                 }
 609
 610                 $request = $this->getRequest();
 611                 $response = $request->response();
 612
 613                 // Origin: header is a space-separated list of origins, check all of them
 614                 $originHeader = $request->getHeader( 'Origin' );
 615                 if ( $originHeader === false ) {
 616                         $origins = [];
 617                 } else {
 618                         $originHeader = trim( $originHeader );
 619                         $origins = preg_split( '/\s+/', $originHeader );
 620                 }
 621
 622                 if ( !in_array( $originParam, $origins ) ) {
 623                         // origin parameter set but incorrect
 624                         // Send a 403 response
 625                         $response->statusHeader( 403 );
 626                         $response->header( 'Cache-Control: no-cache' );
 627                         echo "'origin' parameter does not match Origin header\n";
 628
 629                         return false;
 630                 }
 631
 632                 $config = $this->getConfig();
 633                 $matchOrigin = count( $origins ) === 1 && self::matchOrigin(
 634                         $originParam,
 635                         $config->get( 'CrossSiteAJAXdomains' ),
 636                         $config->get( 'CrossSiteAJAXdomainExceptions' )
 637                 );
 638
 639                 if ( $matchOrigin ) {
 640                         $requestedMethod = $request->getHeader( 'Access-Control-Request-Method' );
 641                         $preflight = $request->getMethod() === 'OPTIONS' && $requestedMethod !== false;
 642                         if ( $preflight ) {
 643                                 // This is a CORS preflight request
 644                                 if ( $requestedMethod !== 'POST' && $requestedMethod !== 'GET' ) {
 645                                         // If method is not a case-sensitive match, do not set any additional headers and terminate.
 646                                         return true;
 647                                 }
 648                                 // We allow the actual request to send the following headers
 649                                 $requestedHeaders = $request->getHeader( 'Access-Control-Request-Headers' );
 650                                 if ( $requestedHeaders !== false ) {
 651                                         if ( !self::matchRequestedHeaders( $requestedHeaders ) ) {
 652                                                 return true;
 653                                         }
 654                                         $response->header( 'Access-Control-Allow-Headers: ' . $requestedHeaders );
 655                                 }
 656
 657                                 // We only allow the actual request to be GET or POST
 658                                 $response->header( 'Access-Control-Allow-Methods: POST, GET' );
 659                         }
 660
 661                         $response->header( "Access-Control-Allow-Origin: $originHeader" );
 662                         $response->header( 'Access-Control-Allow-Credentials: true' );
 663                         // http://www.w3.org/TR/resource-timing/#timing-allow-origin
 664                         $response->header( "Timing-Allow-Origin: $originHeader" );
 665
 666                         if ( !$preflight ) {
 667                                 $response->header(
 668                                         'Access-Control-Expose-Headers: MediaWiki-API-Error, Retry-After, X-Database-Lag'
 669                                 );
 670                         }
 671                 }
 672
 673                 $this->getOutput()->addVaryHeader( 'Origin' );
 674                 return true;
 675         }
 676
 677         /**
 678          * Attempt to match an Origin header against a set of rules and a set of exceptions
 679          * @param string $value Origin header
 680          * @param array $rules Set of wildcard rules
 681          * @param array $exceptions Set of wildcard rules
 682          * @return bool True if $value matches a rule in $rules and doesn't match
 683          *    any rules in $exceptions, false otherwise
 684          */
 685         protected static function matchOrigin( $value, $rules, $exceptions ) {
 686                 foreach ( $rules as $rule ) {
 687                         if ( preg_match( self::wildcardToRegex( $rule ), $value ) ) {
 688                                 // Rule matches, check exceptions
 689                                 foreach ( $exceptions as $exc ) {
 690                                         if ( preg_match( self::wildcardToRegex( $exc ), $value ) ) {
 691                                                 return false;
 692                                         }
 693                                 }
 694
 695                                 return true;
 696                         }
 697                 }
 698
 699                 return false;
 700         }
 701
 702         /**
 703          * Attempt to validate the value of Access-Control-Request-Headers against a list
 704          * of headers that we allow the follow up request to send.
 705          *
 706          * @param string $requestedHeaders Comma seperated list of HTTP headers
 707          * @return bool True if all requested headers are in the list of allowed headers
 708          */
 709         protected static function matchRequestedHeaders( $requestedHeaders ) {
 710                 if ( trim( $requestedHeaders ) === '' ) {
 711                         return true;
 712                 }
 713                 $requestedHeaders = explode( ',', $requestedHeaders );
 714                 $allowedAuthorHeaders = array_flip( [
 715                         /* simple headers (see spec) */
 716                         'accept',
 717                         'accept-language',
 718                         'content-language',
 719                         'content-type',
 720                         /* non-authorable headers in XHR, which are however requested by some UAs */
 721                         'accept-encoding',
 722                         'dnt',
 723                         'origin',
 724                         /* MediaWiki whitelist */
 725                         'api-user-agent',
 726                 ] );
 727                 foreach ( $requestedHeaders as $rHeader ) {
 728                         $rHeader = strtolower( trim( $rHeader ) );
 729                         if ( !isset( $allowedAuthorHeaders[$rHeader] ) ) {
 730                                 wfDebugLog( 'api', 'CORS preflight failed on requested header: ' . $rHeader );
 731                                 return false;
 732                         }
 733                 }
 734                 return true;
 735         }
 736
 737         /**
 738          * Helper function to convert wildcard string into a regex
 739          * '*' => '.*?'
 740          * '?' => '.'
 741          *
 742          * @param string $wildcard String with wildcards
 743          * @return string Regular expression
 744          */
 745         protected static function wildcardToRegex( $wildcard ) {
 746                 $wildcard = preg_quote( $wildcard, '/' );
 747                 $wildcard = str_replace(
 748                         [ '\*', '\?' ],
 749                         [ '.*?', '.' ],
 750                         $wildcard
 751                 );
 752
 753                 return "/^https?:\/\/$wildcard$/";
 754         }
 755
 756         /**
 757          * Send caching headers
 758          * @param bool $isError Whether an error response is being output
 759          * @since 1.26 added $isError parameter
 760          */
 761         protected function sendCacheHeaders( $isError ) {
 762                 $response = $this->getRequest()->response();
 763                 $out = $this->getOutput();
 764
 765                 $out->addVaryHeader( 'Treat-as-Untrusted' );
 766
 767                 $config = $this->getConfig();
 768
 769                 if ( $config->get( 'VaryOnXFP' ) ) {
 770                         $out->addVaryHeader( 'X-Forwarded-Proto' );
 771                 }
 772
 773                 if ( !$isError && $this->mModule &&
 774                         ( $this->getRequest()->getMethod() === 'GET' || $this->getRequest()->getMethod() === 'HEAD' )
 775                 ) {
 776                         $etag = $this->mModule->getConditionalRequestData( 'etag' );
 777                         if ( $etag !== null ) {
 778                                 $response->header( "ETag: $etag" );
 779                         }
 780                         $lastMod = $this->mModule->getConditionalRequestData( 'last-modified' );
 781                         if ( $lastMod !== null ) {
 782                                 $response->header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $lastMod ) );
 783                         }
 784                 }
 785
 786                 // The logic should be:
 787                 // $this->mCacheControl['max-age'] is set?
 788                 //    Use it, the module knows better than our guess.
 789                 // !$this->mModule || $this->mModule->isWriteMode(), and mCacheMode is private?
 790                 //    Use 0 because we can guess caching is probably the wrong thing to do.
 791                 // Use $this->getParameter( 'maxage' ), which already defaults to 0.
 792                 $maxage = 0;
 793                 if ( isset( $this->mCacheControl['max-age'] ) ) {
 794                         $maxage = $this->mCacheControl['max-age'];
 795                 } elseif ( ( $this->mModule && !$this->mModule->isWriteMode() ) ||
 796                         $this->mCacheMode !== 'private'
 797                 ) {
 798                         $maxage = $this->getParameter( 'maxage' );
 799                 }
 800                 $privateCache = 'private, must-revalidate, max-age=' . $maxage;
 801
 802                 if ( $this->mCacheMode == 'private' ) {
 803                         $response->header( "Cache-Control: $privateCache" );
 804                         return;
 805                 }
 806
 807                 $useKeyHeader = $config->get( 'UseKeyHeader' );
 808                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 809                         $out->addVaryHeader( 'Cookie' );
 810                         $response->header( $out->getVaryHeader() );
 811                         if ( $useKeyHeader ) {
 812                                 $response->header( $out->getKeyHeader() );
 813                                 if ( $out->haveCacheVaryCookies() ) {
 814                                         // Logged in, mark this request private
 815                                         $response->header( "Cache-Control: $privateCache" );
 816                                         return;
 817                                 }
 818                                 // Logged out, send normal public headers below
 819                         } elseif ( MediaWiki\Session\SessionManager::getGlobalSession()->isPersistent() ) {
 820                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 821                                 // Mark request private
 822                                 $response->header( "Cache-Control: $privateCache" );
 823
 824                                 return;
 825                         } // else no Key and anonymous, send public headers below
 826                 }
 827
 828                 // Send public headers
 829                 $response->header( $out->getVaryHeader() );
 830                 if ( $useKeyHeader ) {
 831                         $response->header( $out->getKeyHeader() );
 832                 }
 833
 834                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 835                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 836                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 837                 }
 838                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 839                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 840                 }
 841
 842                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 843                         // Public cache not requested
 844                         // Sending a Vary header in this case is harmless, and protects us
 845                         // against conditional calls of setCacheMaxAge().
 846                         $response->header( "Cache-Control: $privateCache" );
 847
 848                         return;
 849                 }
 850
 851                 $this->mCacheControl['public'] = true;
 852
 853                 // Send an Expires header
 854                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 855                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 856                 $response->header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 857
 858                 // Construct the Cache-Control header
 859                 $ccHeader = '';
 860                 $separator = '';
 861                 foreach ( $this->mCacheControl as $name => $value ) {
 862                         if ( is_bool( $value ) ) {
 863                                 if ( $value ) {
 864                                         $ccHeader .= $separator . $name;
 865                                         $separator = ', ';
 866                                 }
 867                         } else {
 868                                 $ccHeader .= $separator . "$name=$value";
 869                                 $separator = ', ';
 870                         }
 871                 }
 872
 873                 $response->header( "Cache-Control: $ccHeader" );
 874         }
 875
 876         /**
 877          * Create the printer for error output
 878          */
 879         private function createErrorPrinter() {
 880                 if ( !isset( $this->mPrinter ) ) {
 881                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 882                         if ( !$this->mModuleMgr->isDefined( $value, 'format' ) ) {
 883                                 $value = self::API_DEFAULT_FORMAT;
 884                         }
 885                         $this->mPrinter = $this->createPrinterByName( $value );
 886                 }
 887
 888                 // Printer may not be able to handle errors. This is particularly
 889                 // likely if the module returns something for getCustomPrinter().
 890                 if ( !$this->mPrinter->canPrintErrors() ) {
 891                         $this->mPrinter = $this->createPrinterByName( self::API_DEFAULT_FORMAT );
 892                 }
 893         }
 894
 895         /**
 896          * Create an error message for the given exception.
 897          *
 898          * If the exception is a UsageException then
 899          * UsageException::getMessageArray() will be called to create the message.
 900          *
 901          * @param Exception $e
 902          * @return array ['code' => 'some string', 'info' => 'some other string']
 903          * @since 1.27
 904          */
 905         protected function errorMessageFromException( $e ) {
 906                 if ( $e instanceof UsageException ) {
 907                         // User entered incorrect parameters - generate error response
 908                         $errMessage = $e->getMessageArray();
 909                 } else {
 910                         $config = $this->getConfig();
 911                         // Something is seriously wrong
 912                         if ( ( $e instanceof DBQueryError ) && !$config->get( 'ShowSQLErrors' ) ) {
 913                                 $info = 'Database query error';
 914                         } else {
 915                                 $info = "Exception Caught: {$e->getMessage()}";
 916                         }
 917
 918                         $errMessage = [
 919                                 'code' => 'internal_api_error_' . get_class( $e ),
 920                                 'info' => '[' . WebRequest::getRequestId() . '] ' . $info,
 921                         ];
 922                 }
 923                 return $errMessage;
 924         }
 925
 926         /**
 927          * Replace the result data with the information about an exception.
 928          * Returns the error code
 929          * @param Exception $e
 930          * @return string
 931          */
 932         protected function substituteResultWithError( $e ) {
 933                 $result = $this->getResult();
 934                 $config = $this->getConfig();
 935
 936                 $errMessage = $this->errorMessageFromException( $e );
 937                 if ( $e instanceof UsageException ) {
 938                         // User entered incorrect parameters - generate error response
 939                         $link = wfExpandUrl( wfScript( 'api' ) );
 940                         ApiResult::setContentValue( $errMessage, 'docref', "See $link for API usage" );
 941                 } else {
 942                         // Something is seriously wrong
 943                         if ( $config->get( 'ShowExceptionDetails' ) ) {
 944                                 ApiResult::setContentValue(
 945                                         $errMessage,
 946                                         'trace',
 947                                         MWExceptionHandler::getRedactedTraceAsString( $e )
 948                                 );
 949                         }
 950                 }
 951
 952                 // Remember all the warnings to re-add them later
 953                 $warnings = $result->getResultData( [ 'warnings' ] );
 954
 955                 $result->reset();
 956                 // Re-add the id
 957                 $requestid = $this->getParameter( 'requestid' );
 958                 if ( !is_null( $requestid ) ) {
 959                         $result->addValue( null, 'requestid', $requestid, ApiResult::NO_SIZE_CHECK );
 960                 }
 961                 if ( $config->get( 'ShowHostnames' ) ) {
 962                         // servedby is especially useful when debugging errors
 963                         $result->addValue( null, 'servedby', wfHostname(), ApiResult::NO_SIZE_CHECK );
 964                 }
 965                 if ( $warnings !== null ) {
 966                         $result->addValue( null, 'warnings', $warnings, ApiResult::NO_SIZE_CHECK );
 967                 }
 968
 969                 $result->addValue( null, 'error', $errMessage, ApiResult::NO_SIZE_CHECK );
 970
 971                 return $errMessage['code'];
 972         }
 973
 974         /**
 975          * Set up for the execution.
 976          * @return array
 977          */
 978         protected function setupExecuteAction() {
 979                 // First add the id to the top element
 980                 $result = $this->getResult();
 981                 $requestid = $this->getParameter( 'requestid' );
 982                 if ( !is_null( $requestid ) ) {
 983                         $result->addValue( null, 'requestid', $requestid );
 984                 }
 985
 986                 if ( $this->getConfig()->get( 'ShowHostnames' ) ) {
 987                         $servedby = $this->getParameter( 'servedby' );
 988                         if ( $servedby ) {
 989                                 $result->addValue( null, 'servedby', wfHostname() );
 990                         }
 991                 }
 992
 993                 if ( $this->getParameter( 'curtimestamp' ) ) {
 994                         $result->addValue( null, 'curtimestamp', wfTimestamp( TS_ISO_8601, time() ),
 995                                 ApiResult::NO_SIZE_CHECK );
 996                 }
 997
 998                 $params = $this->extractRequestParams();
 999
1000                 $this->mAction = $params['action'];
1001
1002                 if ( !is_string( $this->mAction ) ) {
1003                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
1004                 }
1005
1006                 return $params;
1007         }
1008
1009         /**
1010          * Set up the module for response
1011          * @return ApiBase The module that will handle this action
1012          * @throws MWException
1013          * @throws UsageException
1014          */
1015         protected function setupModule() {
1016                 // Instantiate the module requested by the user
1017                 $module = $this->mModuleMgr->getModule( $this->mAction, 'action' );
1018                 if ( $module === null ) {
1019                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
1020                 }
1021                 $moduleParams = $module->extractRequestParams();
1022
1023                 // Check token, if necessary
1024                 if ( $module->needsToken() === true ) {
1025                         throw new MWException(
1026                                 "Module '{$module->getModuleName()}' must be updated for the new token handling. " .
1027                                 'See documentation for ApiBase::needsToken for details.'
1028                         );
1029                 }
1030                 if ( $module->needsToken() ) {
1031                         if ( !$module->mustBePosted() ) {
1032                                 throw new MWException(
1033                                         "Module '{$module->getModuleName()}' must require POST to use tokens."
1034                                 );
1035                         }
1036
1037                         if ( !isset( $moduleParams['token'] ) ) {
1038                                 $this->dieUsageMsg( [ 'missingparam', 'token' ] );
1039                         }
1040
1041                         if ( !$this->getConfig()->get( 'DebugAPI' ) &&
1042                                 array_key_exists(
1043                                         $module->encodeParamName( 'token' ),
1044                                         $this->getRequest()->getQueryValues()
1045                                 )
1046                         ) {
1047                                 $this->dieUsage(
1048                                         "The '{$module->encodeParamName( 'token' )}' parameter was " .
1049                                                 'found in the query string, but must be in the POST body',
1050                                         'mustposttoken'
1051                                 );
1052                         }
1053
1054                         if ( !$module->validateToken( $moduleParams['token'], $moduleParams ) ) {
1055                                 $this->dieUsageMsg( 'sessionfailure' );
1056                         }
1057                 }
1058
1059                 return $module;
1060         }
1061
1062         /**
1063          * Check the max lag if necessary
1064          * @param ApiBase $module Api module being used
1065          * @param array $params Array an array containing the request parameters.
1066          * @return bool True on success, false should exit immediately
1067          */
1068         protected function checkMaxLag( $module, $params ) {
1069                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
1070                         $maxLag = $params['maxlag'];
1071                         list( $host, $lag ) = wfGetLB()->getMaxLag();
1072                         if ( $lag > $maxLag ) {
1073                                 $response = $this->getRequest()->response();
1074
1075                                 $response->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
1076                                 $response->header( 'X-Database-Lag: ' . intval( $lag ) );
1077
1078                                 if ( $this->getConfig()->get( 'ShowHostnames' ) ) {
1079                                         $this->dieUsage( "Waiting for $host: $lag seconds lagged", 'maxlag' );
1080                                 }
1081
1082                                 $this->dieUsage( "Waiting for a database server: $lag seconds lagged", 'maxlag' );
1083                         }
1084                 }
1085
1086                 return true;
1087         }
1088
1089         /**
1090          * Check selected RFC 7232 precondition headers
1091          *
1092          * RFC 7232 envisions a particular model where you send your request to "a
1093          * resource", and for write requests that you can read "the resource" by
1094          * changing the method to GET. When the API receives a GET request, it
1095          * works out even though "the resource" from RFC 7232's perspective might
1096          * be many resources from MediaWiki's perspective. But it totally fails for
1097          * a POST, since what HTTP sees as "the resource" is probably just
1098          * "/api.php" with all the interesting bits in the body.
1099          *
1100          * Therefore, we only support RFC 7232 precondition headers for GET (and
1101          * HEAD). That means we don't need to bother with If-Match and
1102          * If-Unmodified-Since since they only apply to modification requests.
1103          *
1104          * And since we don't support Range, If-Range is ignored too.
1105          *
1106          * @since 1.26
1107          * @param ApiBase $module Api module being used
1108          * @return bool True on success, false should exit immediately
1109          */
1110         protected function checkConditionalRequestHeaders( $module ) {
1111                 if ( $this->mInternalMode ) {
1112                         // No headers to check in internal mode
1113                         return true;
1114                 }
1115
1116                 if ( $this->getRequest()->getMethod() !== 'GET' && $this->getRequest()->getMethod() !== 'HEAD' ) {
1117                         // Don't check POSTs
1118                         return true;
1119                 }
1120
1121                 $return304 = false;
1122
1123                 $ifNoneMatch = array_diff(
1124                         $this->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST ) ?: [],
1125                         [ '' ]
1126                 );
1127                 if ( $ifNoneMatch ) {
1128                         if ( $ifNoneMatch === [ '*' ] ) {
1129                                 // API responses always "exist"
1130                                 $etag = '*';
1131                         } else {
1132                                 $etag = $module->getConditionalRequestData( 'etag' );
1133                         }
1134                 }
1135                 if ( $ifNoneMatch && $etag !== null ) {
1136                         $test = substr( $etag, 0, 2 ) === 'W/' ? substr( $etag, 2 ) : $etag;
1137                         $match = array_map( function ( $s ) {
1138                                 return substr( $s, 0, 2 ) === 'W/' ? substr( $s, 2 ) : $s;
1139                         }, $ifNoneMatch );
1140                         $return304 = in_array( $test, $match, true );
1141                 } else {
1142                         $value = trim( $this->getRequest()->getHeader( 'If-Modified-Since' ) );
1143
1144                         // Some old browsers sends sizes after the date, like this:
1145                         //  Wed, 20 Aug 2003 06:51:19 GMT; length=5202
1146                         // Ignore that.
1147                         $i = strpos( $value, ';' );
1148                         if ( $i !== false ) {
1149                                 $value = trim( substr( $value, 0, $i ) );
1150                         }
1151
1152                         if ( $value !== '' ) {
1153                                 try {
1154                                         $ts = new MWTimestamp( $value );
1155                                         if (
1156                                                 // RFC 7231 IMF-fixdate
1157                                                 $ts->getTimestamp( TS_RFC2822 ) === $value ||
1158                                                 // RFC 850
1159                                                 $ts->format( 'l, d-M-y H:i:s' ) . ' GMT' === $value ||
1160                                                 // asctime (with and without space-padded day)
1161                                                 $ts->format( 'D M j H:i:s Y' ) === $value ||
1162                                                 $ts->format( 'D M  j H:i:s Y' ) === $value
1163                                         ) {
1164                                                 $lastMod = $module->getConditionalRequestData( 'last-modified' );
1165                                                 if ( $lastMod !== null ) {
1166                                                         // Mix in some MediaWiki modification times
1167                                                         $modifiedTimes = [
1168                                                                 'page' => $lastMod,
1169                                                                 'user' => $this->getUser()->getTouched(),
1170                                                                 'epoch' => $this->getConfig()->get( 'CacheEpoch' ),
1171                                                         ];
1172                                                         if ( $this->getConfig()->get( 'UseSquid' ) ) {
1173                                                                 // T46570: the core page itself may not change, but resources might
1174                                                                 $modifiedTimes['sepoch'] = wfTimestamp(
1175                                                                         TS_MW, time() - $this->getConfig()->get( 'SquidMaxage' )
1176                                                                 );
1177                                                         }
1178                                                         Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this->getOutput() ] );
1179                                                         $lastMod = max( $modifiedTimes );
1180                                                         $return304 = wfTimestamp( TS_MW, $lastMod ) <= $ts->getTimestamp( TS_MW );
1181                                                 }
1182                                         }
1183                                 } catch ( TimestampException $e ) {
1184                                         // Invalid timestamp, ignore it
1185                                 }
1186                         }
1187                 }
1188
1189                 if ( $return304 ) {
1190                         $this->getRequest()->response()->statusHeader( 304 );
1191
1192                         // Avoid outputting the compressed representation of a zero-length body
1193                         MediaWiki\suppressWarnings();
1194                         ini_set( 'zlib.output_compression', 0 );
1195                         MediaWiki\restoreWarnings();
1196                         wfClearOutputBuffers();
1197
1198                         return false;
1199                 }
1200
1201                 return true;
1202         }
1203
1204         /**
1205          * Check for sufficient permissions to execute
1206          * @param ApiBase $module An Api module
1207          */
1208         protected function checkExecutePermissions( $module ) {
1209                 $user = $this->getUser();
1210                 if ( $module->isReadMode() && !User::isEveryoneAllowed( 'read' ) &&
1211                         !$user->isAllowed( 'read' )
1212                 ) {
1213                         $this->dieUsageMsg( 'readrequired' );
1214                 }
1215
1216                 if ( $module->isWriteMode() ) {
1217                         if ( !$this->mEnableWrite ) {
1218                                 $this->dieUsageMsg( 'writedisabled' );
1219                         } elseif ( !$user->isAllowed( 'writeapi' ) ) {
1220                                 $this->dieUsageMsg( 'writerequired' );
1221                         } elseif ( $this->getRequest()->getHeader( 'Promise-Non-Write-API-Action' ) ) {
1222                                 $this->dieUsage(
1223                                         'Promise-Non-Write-API-Action HTTP header cannot be sent to write API modules',
1224                                         'promised-nonwrite-api'
1225                                 );
1226                         }
1227
1228                         $this->checkReadOnly( $module );
1229                 }
1230
1231                 // Allow extensions to stop execution for arbitrary reasons.
1232                 $message = false;
1233                 if ( !Hooks::run( 'ApiCheckCanExecute', [ $module, $user, &$message ] ) ) {
1234                         $this->dieUsageMsg( $message );
1235                 }
1236         }
1237
1238         /**
1239          * Check if the DB is read-only for this user
1240          * @param ApiBase $module An Api module
1241          */
1242         protected function checkReadOnly( $module ) {
1243                 if ( wfReadOnly() ) {
1244                         $this->dieReadOnly();
1245                 }
1246
1247                 if ( $module->isWriteMode()
1248                         && in_array( 'bot', $this->getUser()->getGroups() )
1249                         && wfGetLB()->getServerCount() > 1
1250                 ) {
1251                         $this->checkBotReadOnly();
1252                 }
1253         }
1254
1255         /**
1256          * Check whether we are readonly for bots
1257          */
1258         private function checkBotReadOnly() {
1259                 // Figure out how many servers have passed the lag threshold
1260                 $numLagged = 0;
1261                 $lagLimit = $this->getConfig()->get( 'APIMaxLagThreshold' );
1262                 $laggedServers = [];
1263                 $loadBalancer = wfGetLB();
1264                 foreach ( $loadBalancer->getLagTimes() as $serverIndex => $lag ) {
1265                         if ( $lag > $lagLimit ) {
1266                                 ++$numLagged;
1267                                 $laggedServers[] = $loadBalancer->getServerName( $serverIndex ) . " ({$lag}s)";
1268                         }
1269                 }
1270
1271                 // If a majority of slaves are too lagged then disallow writes
1272                 $slaveCount = wfGetLB()->getServerCount() - 1;
1273                 if ( $numLagged >= ceil( $slaveCount / 2 ) ) {
1274                         $laggedServers = implode( ', ', $laggedServers );
1275                         wfDebugLog(
1276                                 'api-readonly',
1277                                 "Api request failed as read only because the following DBs are lagged: $laggedServers"
1278                         );
1279
1280                         $parsed = $this->parseMsg( [ 'readonlytext' ] );
1281                         $this->dieUsage(
1282                                 $parsed['info'],
1283                                 $parsed['code'],
1284                                 /* http error */
1285                                 0,
1286                                 [ 'readonlyreason' => "Waiting for $numLagged lagged database(s)" ]
1287                         );
1288                 }
1289         }
1290
1291         /**
1292          * Check asserts of the user's rights
1293          * @param array $params
1294          */
1295         protected function checkAsserts( $params ) {
1296                 if ( isset( $params['assert'] ) ) {
1297                         $user = $this->getUser();
1298                         switch ( $params['assert'] ) {
1299                                 case 'user':
1300                                         if ( $user->isAnon() ) {
1301                                                 $this->dieUsage( 'Assertion that the user is logged in failed', 'assertuserfailed' );
1302                                         }
1303                                         break;
1304                                 case 'bot':
1305                                         if ( !$user->isAllowed( 'bot' ) ) {
1306                                                 $this->dieUsage( 'Assertion that the user has the bot right failed', 'assertbotfailed' );
1307                                         }
1308                                         break;
1309                         }
1310                 }
1311         }
1312
1313         /**
1314          * Check POST for external response and setup result printer
1315          * @param ApiBase $module An Api module
1316          * @param array $params An array with the request parameters
1317          */
1318         protected function setupExternalResponse( $module, $params ) {
1319                 $request = $this->getRequest();
1320                 if ( !$request->wasPosted() && $module->mustBePosted() ) {
1321                         // Module requires POST. GET request might still be allowed
1322                         // if $wgDebugApi is true, otherwise fail.
1323                         $this->dieUsageMsgOrDebug( [ 'mustbeposted', $this->mAction ] );
1324                 }
1325
1326                 // See if custom printer is used
1327                 $this->mPrinter = $module->getCustomPrinter();
1328                 if ( is_null( $this->mPrinter ) ) {
1329                         // Create an appropriate printer
1330                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
1331                 }
1332
1333                 if ( $request->getProtocol() === 'http' && (
1334                         $request->getSession()->shouldForceHTTPS() ||
1335                         ( $this->getUser()->isLoggedIn() &&
1336                                 $this->getUser()->requiresHTTPS() )
1337                 ) ) {
1338                         $this->logFeatureUsage( 'https-expected' );
1339                         $this->setWarning( 'HTTP used when HTTPS was expected' );
1340                 }
1341         }
1342
1343         /**
1344          * Execute the actual module, without any error handling
1345          */
1346         protected function executeAction() {
1347                 $params = $this->setupExecuteAction();
1348                 $module = $this->setupModule();
1349                 $this->mModule = $module;
1350
1351                 if ( !$this->mInternalMode ) {
1352                         $this->setRequestExpectations( $module );
1353                 }
1354
1355                 $this->checkExecutePermissions( $module );
1356
1357                 if ( !$this->checkMaxLag( $module, $params ) ) {
1358                         return;
1359                 }
1360
1361                 if ( !$this->checkConditionalRequestHeaders( $module ) ) {
1362                         return;
1363                 }
1364
1365                 if ( !$this->mInternalMode ) {
1366                         $this->setupExternalResponse( $module, $params );
1367                 }
1368
1369                 $this->checkAsserts( $params );
1370
1371                 // Execute
1372                 $module->execute();
1373                 Hooks::run( 'APIAfterExecute', [ &$module ] );
1374
1375                 $this->reportUnusedParams();
1376
1377                 if ( !$this->mInternalMode ) {
1378                         // append Debug information
1379                         MWDebug::appendDebugInfoToApiResult( $this->getContext(), $this->getResult() );
1380
1381                         // Print result data
1382                         $this->printResult( false );
1383                 }
1384         }
1385
1386         /**
1387          * Set database connection, query, and write expectations given this module request
1388          * @param ApiBase $module
1389          */
1390         protected function setRequestExpectations( ApiBase $module ) {
1391                 $limits = $this->getConfig()->get( 'TrxProfilerLimits' );
1392                 $trxProfiler = Profiler::instance()->getTransactionProfiler();
1393                 if ( $this->getRequest()->wasPosted() ) {
1394                         if ( $module->isWriteMode() ) {
1395                                 $trxProfiler->setExpectations( $limits['POST'], __METHOD__ );
1396                         } else {
1397                                 $trxProfiler->setExpectations( $limits['POST-nonwrite'], __METHOD__ );
1398                                 $this->getRequest()->markAsSafeRequest();
1399                         }
1400                 } else {
1401                         $trxProfiler->setExpectations( $limits['GET'], __METHOD__ );
1402                 }
1403         }
1404
1405         /**
1406          * Log the preceding request
1407          * @param float $time Time in seconds
1408          * @param Exception $e Exception caught while processing the request
1409          */
1410         protected function logRequest( $time, $e = null ) {
1411                 $request = $this->getRequest();
1412                 $logCtx = [
1413                         'ts' => time(),
1414                         'ip' => $request->getIP(),
1415                         'userAgent' => $this->getUserAgent(),
1416                         'wiki' => wfWikiID(),
1417                         'timeSpentBackend' => (int) round( $time * 1000 ),
1418                         'hadError' => $e !== null,
1419                         'errorCodes' => [],
1420                         'params' => [],
1421                 ];
1422
1423                 if ( $e ) {
1424                         $logCtx['errorCodes'][] = $this->errorMessageFromException( $e )['code'];
1425                 }
1426
1427                 // Construct space separated message for 'api' log channel
1428                 $msg = "API {$request->getMethod()} " .
1429                         wfUrlencode( str_replace( ' ', '_', $this->getUser()->getName() ) ) .
1430                         " {$logCtx['ip']} " .
1431                         "T={$logCtx['timeSpentBackend']}ms";
1432
1433                 foreach ( $this->getParamsUsed() as $name ) {
1434                         $value = $request->getVal( $name );
1435                         if ( $value === null ) {
1436                                 continue;
1437                         }
1438
1439                         if ( strlen( $value ) > 256 ) {
1440                                 $value = substr( $value, 0, 256 );
1441                                 $encValue = $this->encodeRequestLogValue( $value ) . '[...]';
1442                         } else {
1443                                 $encValue = $this->encodeRequestLogValue( $value );
1444                         }
1445
1446                         $logCtx['params'][$name] = $value;
1447                         $msg .= " {$name}={$encValue}";
1448                 }
1449
1450                 wfDebugLog( 'api', $msg, 'private' );
1451                 // ApiAction channel is for structured data consumers
1452                 wfDebugLog( 'ApiAction', '', 'private', $logCtx );
1453         }
1454
1455         /**
1456          * Encode a value in a format suitable for a space-separated log line.
1457          * @param string $s
1458          * @return string
1459          */
1460         protected function encodeRequestLogValue( $s ) {
1461                 static $table;
1462                 if ( !$table ) {
1463                         $chars = ';@$!*(),/:';
1464                         $numChars = strlen( $chars );
1465                         for ( $i = 0; $i < $numChars; $i++ ) {
1466                                 $table[rawurlencode( $chars[$i] )] = $chars[$i];
1467                         }
1468                 }
1469
1470                 return strtr( rawurlencode( $s ), $table );
1471         }
1472
1473         /**
1474          * Get the request parameters used in the course of the preceding execute() request
1475          * @return array
1476          */
1477         protected function getParamsUsed() {
1478                 return array_keys( $this->mParamsUsed );
1479         }
1480
1481         /**
1482          * Mark parameters as used
1483          * @param string|string[] $params
1484          */
1485         public function markParamsUsed( $params ) {
1486                 $this->mParamsUsed += array_fill_keys( (array)$params, true );
1487         }
1488
1489         /**
1490          * Get a request value, and register the fact that it was used, for logging.
1491          * @param string $name
1492          * @param mixed $default
1493          * @return mixed
1494          */
1495         public function getVal( $name, $default = null ) {
1496                 $this->mParamsUsed[$name] = true;
1497
1498                 $ret = $this->getRequest()->getVal( $name );
1499                 if ( $ret === null ) {
1500                         if ( $this->getRequest()->getArray( $name ) !== null ) {
1501                                 // See bug 10262 for why we don't just implode( '|', ... ) the
1502                                 // array.
1503                                 $this->setWarning(
1504                                         "Parameter '$name' uses unsupported PHP array syntax"
1505                                 );
1506                         }
1507                         $ret = $default;
1508                 }
1509                 return $ret;
1510         }
1511
1512         /**
1513          * Get a boolean request value, and register the fact that the parameter
1514          * was used, for logging.
1515          * @param string $name
1516          * @return bool
1517          */
1518         public function getCheck( $name ) {
1519                 return $this->getVal( $name, null ) !== null;
1520         }
1521
1522         /**
1523          * Get a request upload, and register the fact that it was used, for logging.
1524          *
1525          * @since 1.21
1526          * @param string $name Parameter name
1527          * @return WebRequestUpload
1528          */
1529         public function getUpload( $name ) {
1530                 $this->mParamsUsed[$name] = true;
1531
1532                 return $this->getRequest()->getUpload( $name );
1533         }
1534
1535         /**
1536          * Report unused parameters, so the client gets a hint in case it gave us parameters we don't know,
1537          * for example in case of spelling mistakes or a missing 'g' prefix for generators.
1538          */
1539         protected function reportUnusedParams() {
1540                 $paramsUsed = $this->getParamsUsed();
1541                 $allParams = $this->getRequest()->getValueNames();
1542
1543                 if ( !$this->mInternalMode ) {
1544                         // Printer has not yet executed; don't warn that its parameters are unused
1545                         $printerParams = array_map(
1546                                 [ $this->mPrinter, 'encodeParamName' ],
1547                                 array_keys( $this->mPrinter->getFinalParams() ?: [] )
1548                         );
1549                         $unusedParams = array_diff( $allParams, $paramsUsed, $printerParams );
1550                 } else {
1551                         $unusedParams = array_diff( $allParams, $paramsUsed );
1552                 }
1553
1554                 if ( count( $unusedParams ) ) {
1555                         $s = count( $unusedParams ) > 1 ? 's' : '';
1556                         $this->setWarning( "Unrecognized parameter$s: '" . implode( $unusedParams, "', '" ) . "'" );
1557                 }
1558         }
1559
1560         /**
1561          * Print results using the current printer
1562          *
1563          * @param bool $isError
1564          */
1565         protected function printResult( $isError ) {
1566                 if ( $this->getConfig()->get( 'DebugAPI' ) !== false ) {
1567                         $this->setWarning( 'SECURITY WARNING: $wgDebugAPI is enabled' );
1568                 }
1569
1570                 $printer = $this->mPrinter;
1571                 $printer->initPrinter( false );
1572                 $printer->execute();
1573                 $printer->closePrinter();
1574         }
1575
1576         /**
1577          * @return bool
1578          */
1579         public function isReadMode() {
1580                 return false;
1581         }
1582
1583         /**
1584          * See ApiBase for description.
1585          *
1586          * @return array
1587          */
1588         public function getAllowedParams() {
1589                 return [
1590                         'action' => [
1591                                 ApiBase::PARAM_DFLT => 'help',
1592                                 ApiBase::PARAM_TYPE => 'submodule',
1593                         ],
1594                         'format' => [
1595                                 ApiBase::PARAM_DFLT => ApiMain::API_DEFAULT_FORMAT,
1596                                 ApiBase::PARAM_TYPE => 'submodule',
1597                         ],
1598                         'maxlag' => [
1599                                 ApiBase::PARAM_TYPE => 'integer'
1600                         ],
1601                         'smaxage' => [
1602                                 ApiBase::PARAM_TYPE => 'integer',
1603                                 ApiBase::PARAM_DFLT => 0
1604                         ],
1605                         'maxage' => [
1606                                 ApiBase::PARAM_TYPE => 'integer',
1607                                 ApiBase::PARAM_DFLT => 0
1608                         ],
1609                         'assert' => [
1610                                 ApiBase::PARAM_TYPE => [ 'user', 'bot' ]
1611                         ],
1612                         'requestid' => null,
1613                         'servedby' => false,
1614                         'curtimestamp' => false,
1615                         'origin' => null,
1616                         'uselang' => [
1617                                 ApiBase::PARAM_DFLT => 'user',
1618                         ],
1619                 ];
1620         }
1621
1622         /** @see ApiBase::getExamplesMessages() */
1623         protected function getExamplesMessages() {
1624                 return [
1625                         'action=help'
1626                                 => 'apihelp-help-example-main',
1627                         'action=help&recursivesubmodules=1'
1628                                 => 'apihelp-help-example-recursive',
1629                 ];
1630         }
1631
1632         public function modifyHelp( array &$help, array $options, array &$tocData ) {
1633                 // Wish PHP had an "array_insert_before". Instead, we have to manually
1634                 // reindex the array to get 'permissions' in the right place.
1635                 $oldHelp = $help;
1636                 $help = [];
1637                 foreach ( $oldHelp as $k => $v ) {
1638                         if ( $k === 'submodules' ) {
1639                                 $help['permissions'] = '';
1640                         }
1641                         $help[$k] = $v;
1642                 }
1643                 $help['datatypes'] = '';
1644                 $help['credits'] = '';
1645
1646                 // Fill 'permissions'
1647                 $help['permissions'] .= Html::openElement( 'div',
1648                         [ 'class' => 'apihelp-block apihelp-permissions' ] );
1649                 $m = $this->msg( 'api-help-permissions' );
1650                 if ( !$m->isDisabled() ) {
1651                         $help['permissions'] .= Html::rawElement( 'div', [ 'class' => 'apihelp-block-head' ],
1652                                 $m->numParams( count( self::$mRights ) )->parse()
1653                         );
1654                 }
1655                 $help['permissions'] .= Html::openElement( 'dl' );
1656                 foreach ( self::$mRights as $right => $rightMsg ) {
1657                         $help['permissions'] .= Html::element( 'dt', null, $right );
1658
1659                         $rightMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )->parse();
1660                         $help['permissions'] .= Html::rawElement( 'dd', null, $rightMsg );
1661
1662                         $groups = array_map( function ( $group ) {
1663                                 return $group == '*' ? 'all' : $group;
1664                         }, User::getGroupsWithPermission( $right ) );
1665
1666                         $help['permissions'] .= Html::rawElement( 'dd', null,
1667                                 $this->msg( 'api-help-permissions-granted-to' )
1668                                         ->numParams( count( $groups ) )
1669                                         ->params( $this->getLanguage()->commaList( $groups ) )
1670                                         ->parse()
1671                         );
1672                 }
1673                 $help['permissions'] .= Html::closeElement( 'dl' );
1674                 $help['permissions'] .= Html::closeElement( 'div' );
1675
1676                 // Fill 'datatypes' and 'credits', if applicable
1677                 if ( empty( $options['nolead'] ) ) {
1678                         $level = $options['headerlevel'];
1679                         $tocnumber = &$options['tocnumber'];
1680
1681                         $header = $this->msg( 'api-help-datatypes-header' )->parse();
1682
1683                         // Add an additional span with sanitized ID
1684                         if ( !$this->getConfig()->get( 'ExperimentalHtmlIds' ) ) {
1685                                 $header = Html::element( 'span', [ 'id' => Sanitizer::escapeId( 'main/datatypes' ) ] ) .
1686                                         $header;
1687                         }
1688                         $help['datatypes'] .= Html::rawElement( 'h' . min( 6, $level ),
1689                                 [ 'id' => 'main/datatypes', 'class' => 'apihelp-header' ],
1690                                 $header
1691                         );
1692                         $help['datatypes'] .= $this->msg( 'api-help-datatypes' )->parseAsBlock();
1693                         if ( !isset( $tocData['main/datatypes'] ) ) {
1694                                 $tocnumber[$level]++;
1695                                 $tocData['main/datatypes'] = [
1696                                         'toclevel' => count( $tocnumber ),
1697                                         'level' => $level,
1698                                         'anchor' => 'main/datatypes',
1699                                         'line' => $header,
1700                                         'number' => implode( '.', $tocnumber ),
1701                                         'index' => false,
1702                                 ];
1703                         }
1704
1705                         // Add an additional span with sanitized ID
1706                         if ( !$this->getConfig()->get( 'ExperimentalHtmlIds' ) ) {
1707                                 $header = Html::element( 'span', [ 'id' => Sanitizer::escapeId( 'main/credits' ) ] ) .
1708                                         $header;
1709                         }
1710                         $header = $this->msg( 'api-credits-header' )->parse();
1711                         $help['credits'] .= Html::rawElement( 'h' . min( 6, $level ),
1712                                 [ 'id' => 'main/credits', 'class' => 'apihelp-header' ],
1713                                 $header
1714                         );
1715                         $help['credits'] .= $this->msg( 'api-credits' )->useDatabase( false )->parseAsBlock();
1716                         if ( !isset( $tocData['main/credits'] ) ) {
1717                                 $tocnumber[$level]++;
1718                                 $tocData['main/credits'] = [
1719                                         'toclevel' => count( $tocnumber ),
1720                                         'level' => $level,
1721                                         'anchor' => 'main/credits',
1722                                         'line' => $header,
1723                                         'number' => implode( '.', $tocnumber ),
1724                                         'index' => false,
1725                                 ];
1726                         }
1727                 }
1728         }
1729
1730         private $mCanApiHighLimits = null;
1731
1732         /**
1733          * Check whether the current user is allowed to use high limits
1734          * @return bool
1735          */
1736         public function canApiHighLimits() {
1737                 if ( !isset( $this->mCanApiHighLimits ) ) {
1738                         $this->mCanApiHighLimits = $this->getUser()->isAllowed( 'apihighlimits' );
1739                 }
1740
1741                 return $this->mCanApiHighLimits;
1742         }
1743
1744         /**
1745          * Overrides to return this instance's module manager.
1746          * @return ApiModuleManager
1747          */
1748         public function getModuleManager() {
1749                 return $this->mModuleMgr;
1750         }
1751
1752         /**
1753          * Fetches the user agent used for this request
1754          *
1755          * The value will be the combination of the 'Api-User-Agent' header (if
1756          * any) and the standard User-Agent header (if any).
1757          *
1758          * @return string
1759          */
1760         public function getUserAgent() {
1761                 return trim(
1762                         $this->getRequest()->getHeader( 'Api-user-agent' ) . ' ' .
1763                         $this->getRequest()->getHeader( 'User-agent' )
1764                 );
1765         }
1766
1767         /************************************************************************//**
1768          * @name   Deprecated
1769          * @{
1770          */
1771
1772         /**
1773          * Sets whether the pretty-printer should format *bold* and $italics$
1774          *
1775          * @deprecated since 1.25
1776          * @param bool $help
1777          */
1778         public function setHelp( $help = true ) {
1779                 wfDeprecated( __METHOD__, '1.25' );
1780                 $this->mPrinter->setHelp( $help );
1781         }
1782
1783         /**
1784          * Override the parent to generate help messages for all available modules.
1785          *
1786          * @deprecated since 1.25
1787          * @return string
1788          */
1789         public function makeHelpMsg() {
1790                 wfDeprecated( __METHOD__, '1.25' );
1791
1792                 $this->setHelp();
1793                 $cacheHelpTimeout = $this->getConfig()->get( 'APICacheHelpTimeout' );
1794
1795                 return ObjectCache::getMainWANInstance()->getWithSetCallback(
1796                         wfMemcKey(
1797                                 'apihelp',
1798                                 $this->getModuleName(),
1799                                 str_replace( ' ', '_', SpecialVersion::getVersion( 'nodb' ) )
1800                         ),
1801                         $cacheHelpTimeout > 0 ? $cacheHelpTimeout : WANObjectCache::TTL_UNCACHEABLE,
1802                         [ $this, 'reallyMakeHelpMsg' ]
1803                 );
1804         }
1805
1806         /**
1807          * @deprecated since 1.25
1808          * @return mixed|string
1809          */
1810         public function reallyMakeHelpMsg() {
1811                 wfDeprecated( __METHOD__, '1.25' );
1812                 $this->setHelp();
1813
1814                 // Use parent to make default message for the main module
1815                 $msg = parent::makeHelpMsg();
1816
1817                 $asterisks = str_repeat( '*** ', 14 );
1818                 $msg .= "\n\n$asterisks Modules  $asterisks\n\n";
1819
1820                 foreach ( $this->mModuleMgr->getNames( 'action' ) as $name ) {
1821                         $module = $this->mModuleMgr->getModule( $name );
1822                         $msg .= self::makeHelpMsgHeader( $module, 'action' );
1823
1824                         $msg2 = $module->makeHelpMsg();
1825                         if ( $msg2 !== false ) {
1826                                 $msg .= $msg2;
1827                         }
1828                         $msg .= "\n";
1829                 }
1830
1831                 $msg .= "\n$asterisks Permissions $asterisks\n\n";
1832                 foreach ( self::$mRights as $right => $rightMsg ) {
1833                         $rightsMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )
1834                                 ->useDatabase( false )
1835                                 ->inLanguage( 'en' )
1836                                 ->text();
1837                         $groups = User::getGroupsWithPermission( $right );
1838                         $msg .= '* ' . $right . " *\n  $rightsMsg" .
1839                                 "\nGranted to:\n  " . str_replace( '*', 'all', implode( ', ', $groups ) ) . "\n\n";
1840                 }
1841
1842                 $msg .= "\n$asterisks Formats  $asterisks\n\n";
1843                 foreach ( $this->mModuleMgr->getNames( 'format' ) as $name ) {
1844                         $module = $this->mModuleMgr->getModule( $name );
1845                         $msg .= self::makeHelpMsgHeader( $module, 'format' );
1846                         $msg2 = $module->makeHelpMsg();
1847                         if ( $msg2 !== false ) {
1848                                 $msg .= $msg2;
1849                         }
1850                         $msg .= "\n";
1851                 }
1852
1853                 $credits = $this->msg( 'api-credits' )->useDatabase( 'false' )->inLanguage( 'en' )->text();
1854                 $credits = str_replace( "\n", "\n   ", $credits );
1855                 $msg .= "\n*** Credits: ***\n   $credits\n";
1856
1857                 return $msg;
1858         }
1859
1860         /**
1861          * @deprecated since 1.25
1862          * @param ApiBase $module
1863          * @param string $paramName What type of request is this? e.g. action,
1864          *    query, list, prop, meta, format
1865          * @return string
1866          */
1867         public static function makeHelpMsgHeader( $module, $paramName ) {
1868                 wfDeprecated( __METHOD__, '1.25' );
1869                 $modulePrefix = $module->getModulePrefix();
1870                 if ( strval( $modulePrefix ) !== '' ) {
1871                         $modulePrefix = "($modulePrefix) ";
1872                 }
1873
1874                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
1875         }
1876
1877         /**@}*/
1878
1879 }
1880
1881 /**
1882  * This exception will be thrown when dieUsage is called to stop module execution.
1883  *
1884  * @ingroup API
1885  */
1886 class UsageException extends MWException {
1887
1888         private $mCodestr;
1889
1890         /**
1891          * @var null|array
1892          */
1893         private $mExtraData;
1894
1895         /**
1896          * @param string $message
1897          * @param string $codestr
1898          * @param int $code
1899          * @param array|null $extradata
1900          */
1901         public function __construct( $message, $codestr, $code = 0, $extradata = null ) {
1902                 parent::__construct( $message, $code );
1903                 $this->mCodestr = $codestr;
1904                 $this->mExtraData = $extradata;
1905         }
1906
1907         /**
1908          * @return string
1909          */
1910         public function getCodeString() {
1911                 return $this->mCodestr;
1912         }
1913
1914         /**
1915          * @return array
1916          */
1917         public function getMessageArray() {
1918                 $result = [
1919                         'code' => $this->mCodestr,
1920                         'info' => $this->getMessage()
1921                 ];
1922                 if ( is_array( $this->mExtraData ) ) {
1923                         $result = array_merge( $result, $this->mExtraData );
1924                 }
1925
1926                 return $result;
1927         }
1928
1929         /**
1930          * @return string
1931          */
1932         public function __toString() {
1933                 return "{$this->getCodeString()}: {$this->getMessage()}";
1934         }
1935 }
1936
1937 /**
1938  * For really cool vim folding this needs to be at the end:
1939  * vim: foldmarker=@{,@} foldmethod=marker
1940  */