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                 'logout' => 'ApiLogout',
  53                 'createaccount' => 'ApiCreateAccount',
  54                 'query' => 'ApiQuery',
  55                 'expandtemplates' => 'ApiExpandTemplates',
  56                 'parse' => 'ApiParse',
  57                 'stashedit' => 'ApiStashEdit',
  58                 'opensearch' => 'ApiOpenSearch',
  59                 'feedcontributions' => 'ApiFeedContributions',
  60                 'feedrecentchanges' => 'ApiFeedRecentChanges',
  61                 'feedwatchlist' => 'ApiFeedWatchlist',
  62                 'help' => 'ApiHelp',
  63                 'paraminfo' => 'ApiParamInfo',
  64                 'rsd' => 'ApiRsd',
  65                 'compare' => 'ApiComparePages',
  66                 'tokens' => 'ApiTokens',
  67                 'checktoken' => 'ApiCheckToken',
  68
  69                 // Write modules
  70                 'purge' => 'ApiPurge',
  71                 'setnotificationtimestamp' => 'ApiSetNotificationTimestamp',
  72                 'rollback' => 'ApiRollback',
  73                 'delete' => 'ApiDelete',
  74                 'undelete' => 'ApiUndelete',
  75                 'protect' => 'ApiProtect',
  76                 'block' => 'ApiBlock',
  77                 'unblock' => 'ApiUnblock',
  78                 'move' => 'ApiMove',
  79                 'edit' => 'ApiEditPage',
  80                 'upload' => 'ApiUpload',
  81                 'filerevert' => 'ApiFileRevert',
  82                 'emailuser' => 'ApiEmailUser',
  83                 'watch' => 'ApiWatch',
  84                 'patrol' => 'ApiPatrol',
  85                 'import' => 'ApiImport',
  86                 'clearhasmsg' => 'ApiClearHasMsg',
  87                 'userrights' => 'ApiUserrights',
  88                 'options' => 'ApiOptions',
  89                 'imagerotate' => 'ApiImageRotate',
  90                 'revisiondelete' => 'ApiRevisionDelete',
  91                 'managetags' => 'ApiManageTags',
  92                 'tag' => 'ApiTag',
  93                 'mergehistory' => 'ApiMergeHistory',
  94         ];
  95
  96         /**
  97          * List of available formats: format name => format class
  98          */
  99         private static $Formats = [
 100                 'json' => 'ApiFormatJson',
 101                 'jsonfm' => 'ApiFormatJson',
 102                 'php' => 'ApiFormatPhp',
 103                 'phpfm' => 'ApiFormatPhp',
 104                 'xml' => 'ApiFormatXml',
 105                 'xmlfm' => 'ApiFormatXml',
 106                 'rawfm' => 'ApiFormatJson',
 107                 'none' => 'ApiFormatNone',
 108         ];
 109
 110         // @codingStandardsIgnoreStart String contenation on "msg" not allowed to break long line
 111         /**
 112          * List of user roles that are specifically relevant to the API.
 113          * array( 'right' => array ( 'msg'    => 'Some message with a $1',
 114          *                           'params' => array ( $someVarToSubst ) ),
 115          *                          );
 116          */
 117         private static $mRights = [
 118                 'writeapi' => [
 119                         'msg' => 'right-writeapi',
 120                         'params' => []
 121                 ],
 122                 'apihighlimits' => [
 123                         'msg' => 'api-help-right-apihighlimits',
 124                         'params' => [ ApiBase::LIMIT_SML2, ApiBase::LIMIT_BIG2 ]
 125                 ]
 126         ];
 127         // @codingStandardsIgnoreEnd
 128
 129         /**
 130          * @var ApiFormatBase
 131          */
 132         private $mPrinter;
 133
 134         private $mModuleMgr, $mResult, $mErrorFormatter, $mContinuationManager;
 135         private $mAction;
 136         private $mEnableWrite;
 137         private $mInternalMode, $mSquidMaxage, $mModule;
 138
 139         private $mCacheMode = 'private';
 140         private $mCacheControl = [];
 141         private $mParamsUsed = [];
 142
 143         /**
 144          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 145          *
 146          * @param IContextSource|WebRequest $context If this is an instance of
 147          *    FauxRequest, errors are thrown and no printing occurs
 148          * @param bool $enableWrite Should be set to true if the api may modify data
 149          */
 150         public function __construct( $context = null, $enableWrite = false ) {
 151                 if ( $context === null ) {
 152                         $context = RequestContext::getMain();
 153                 } elseif ( $context instanceof WebRequest ) {
 154                         // BC for pre-1.19
 155                         $request = $context;
 156                         $context = RequestContext::getMain();
 157                 }
 158                 // We set a derivative context so we can change stuff later
 159                 $this->setContext( new DerivativeContext( $context ) );
 160
 161                 if ( isset( $request ) ) {
 162                         $this->getContext()->setRequest( $request );
 163                 }
 164
 165                 $this->mInternalMode = ( $this->getRequest() instanceof FauxRequest );
 166
 167                 // Special handling for the main module: $parent === $this
 168                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 169
 170                 if ( !$this->mInternalMode ) {
 171                         // Impose module restrictions.
 172                         // If the current user cannot read,
 173                         // Remove all modules other than login
 174                         global $wgUser;
 175
 176                         if ( $this->lacksSameOriginSecurity() ) {
 177                                 // If we're in a mode that breaks the same-origin policy, strip
 178                                 // user credentials for security.
 179                                 wfDebug( "API: stripping user credentials when the same-origin policy is not applied\n" );
 180                                 $wgUser = new User();
 181                                 $this->getContext()->setUser( $wgUser );
 182                         }
 183                 }
 184
 185                 $uselang = $this->getParameter( 'uselang' );
 186                 if ( $uselang === 'user' ) {
 187                         // Assume the parent context is going to return the user language
 188                         // for uselang=user (see T85635).
 189                 } else {
 190                         if ( $uselang === 'content' ) {
 191                                 global $wgContLang;
 192                                 $uselang = $wgContLang->getCode();
 193                         }
 194                         $code = RequestContext::sanitizeLangCode( $uselang );
 195                         $this->getContext()->setLanguage( $code );
 196                         if ( !$this->mInternalMode ) {
 197                                 global $wgLang;
 198                                 $wgLang = $this->getContext()->getLanguage();
 199                                 RequestContext::getMain()->setLanguage( $wgLang );
 200                         }
 201                 }
 202
 203                 $config = $this->getConfig();
 204                 $this->mModuleMgr = new ApiModuleManager( $this );
 205                 $this->mModuleMgr->addModules( self::$Modules, 'action' );
 206                 $this->mModuleMgr->addModules( $config->get( 'APIModules' ), 'action' );
 207                 $this->mModuleMgr->addModules( self::$Formats, 'format' );
 208                 $this->mModuleMgr->addModules( $config->get( 'APIFormatModules' ), 'format' );
 209
 210                 Hooks::run( 'ApiMain::moduleManager', [ $this->mModuleMgr ] );
 211
 212                 $this->mResult = new ApiResult( $this->getConfig()->get( 'APIMaxResultSize' ) );
 213                 $this->mErrorFormatter = new ApiErrorFormatter_BackCompat( $this->mResult );
 214                 $this->mResult->setErrorFormatter( $this->mErrorFormatter );
 215                 $this->mResult->setMainForContinuation( $this );
 216                 $this->mContinuationManager = null;
 217                 $this->mEnableWrite = $enableWrite;
 218
 219                 $this->mSquidMaxage = -1; // flag for executeActionWithErrorHandling()
 220                 $this->mCommit = false;
 221         }
 222
 223         /**
 224          * Return true if the API was started by other PHP code using FauxRequest
 225          * @return bool
 226          */
 227         public function isInternalMode() {
 228                 return $this->mInternalMode;
 229         }
 230
 231         /**
 232          * Get the ApiResult object associated with current request
 233          *
 234          * @return ApiResult
 235          */
 236         public function getResult() {
 237                 return $this->mResult;
 238         }
 239
 240         /**
 241          * Get the ApiErrorFormatter object associated with current request
 242          * @return ApiErrorFormatter
 243          */
 244         public function getErrorFormatter() {
 245                 return $this->mErrorFormatter;
 246         }
 247
 248         /**
 249          * Get the continuation manager
 250          * @return ApiContinuationManager|null
 251          */
 252         public function getContinuationManager() {
 253                 return $this->mContinuationManager;
 254         }
 255
 256         /**
 257          * Set the continuation manager
 258          * @param ApiContinuationManager|null
 259          */
 260         public function setContinuationManager( $manager ) {
 261                 if ( $manager !== null ) {
 262                         if ( !$manager instanceof ApiContinuationManager ) {
 263                                 throw new InvalidArgumentException( __METHOD__ . ': Was passed ' .
 264                                         is_object( $manager ) ? get_class( $manager ) : gettype( $manager )
 265                                 );
 266                         }
 267                         if ( $this->mContinuationManager !== null ) {
 268                                 throw new UnexpectedValueException(
 269                                         __METHOD__ . ': tried to set manager from ' . $manager->getSource() .
 270                                         ' when a manager is already set from ' . $this->mContinuationManager->getSource()
 271                                 );
 272                         }
 273                 }
 274                 $this->mContinuationManager = $manager;
 275         }
 276
 277         /**
 278          * Get the API module object. Only works after executeAction()
 279          *
 280          * @return ApiBase
 281          */
 282         public function getModule() {
 283                 return $this->mModule;
 284         }
 285
 286         /**
 287          * Get the result formatter object. Only works after setupExecuteAction()
 288          *
 289          * @return ApiFormatBase
 290          */
 291         public function getPrinter() {
 292                 return $this->mPrinter;
 293         }
 294
 295         /**
 296          * Set how long the response should be cached.
 297          *
 298          * @param int $maxage
 299          */
 300         public function setCacheMaxAge( $maxage ) {
 301                 $this->setCacheControl( [
 302                         'max-age' => $maxage,
 303                         's-maxage' => $maxage
 304                 ] );
 305         }
 306
 307         /**
 308          * Set the type of caching headers which will be sent.
 309          *
 310          * @param string $mode One of:
 311          *    - 'public':     Cache this object in public caches, if the maxage or smaxage
 312          *         parameter is set, or if setCacheMaxAge() was called. If a maximum age is
 313          *         not provided by any of these means, the object will be private.
 314          *    - 'private':    Cache this object only in private client-side caches.
 315          *    - 'anon-public-user-private': Make this object cacheable for logged-out
 316          *         users, but private for logged-in users. IMPORTANT: If this is set, it must be
 317          *         set consistently for a given URL, it cannot be set differently depending on
 318          *         things like the contents of the database, or whether the user is logged in.
 319          *
 320          *  If the wiki does not allow anonymous users to read it, the mode set here
 321          *  will be ignored, and private caching headers will always be sent. In other words,
 322          *  the "public" mode is equivalent to saying that the data sent is as public as a page
 323          *  view.
 324          *
 325          *  For user-dependent data, the private mode should generally be used. The
 326          *  anon-public-user-private mode should only be used where there is a particularly
 327          *  good performance reason for caching the anonymous response, but where the
 328          *  response to logged-in users may differ, or may contain private data.
 329          *
 330          *  If this function is never called, then the default will be the private mode.
 331          */
 332         public function setCacheMode( $mode ) {
 333                 if ( !in_array( $mode, [ 'private', 'public', 'anon-public-user-private' ] ) ) {
 334                         wfDebug( __METHOD__ . ": unrecognised cache mode \"$mode\"\n" );
 335
 336                         // Ignore for forwards-compatibility
 337                         return;
 338                 }
 339
 340                 if ( !User::isEveryoneAllowed( 'read' ) ) {
 341                         // Private wiki, only private headers
 342                         if ( $mode !== 'private' ) {
 343                                 wfDebug( __METHOD__ . ": ignoring request for $mode cache mode, private wiki\n" );
 344
 345                                 return;
 346                         }
 347                 }
 348
 349                 if ( $mode === 'public' && $this->getParameter( 'uselang' ) === 'user' ) {
 350                         // User language is used for i18n, so we don't want to publicly
 351                         // cache. Anons are ok, because if they have non-default language
 352                         // then there's an appropriate Vary header set by whatever set
 353                         // their non-default language.
 354                         wfDebug( __METHOD__ . ": downgrading cache mode 'public' to " .
 355                                 "'anon-public-user-private' due to uselang=user\n" );
 356                         $mode = 'anon-public-user-private';
 357                 }
 358
 359                 wfDebug( __METHOD__ . ": setting cache mode $mode\n" );
 360                 $this->mCacheMode = $mode;
 361         }
 362
 363         /**
 364          * Set directives (key/value pairs) for the Cache-Control header.
 365          * Boolean values will be formatted as such, by including or omitting
 366          * without an equals sign.
 367          *
 368          * Cache control values set here will only be used if the cache mode is not
 369          * private, see setCacheMode().
 370          *
 371          * @param array $directives
 372          */
 373         public function setCacheControl( $directives ) {
 374                 $this->mCacheControl = $directives + $this->mCacheControl;
 375         }
 376
 377         /**
 378          * Create an instance of an output formatter by its name
 379          *
 380          * @param string $format
 381          *
 382          * @return ApiFormatBase
 383          */
 384         public function createPrinterByName( $format ) {
 385                 $printer = $this->mModuleMgr->getModule( $format, 'format' );
 386                 if ( $printer === null ) {
 387                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 388                 }
 389
 390                 return $printer;
 391         }
 392
 393         /**
 394          * Execute api request. Any errors will be handled if the API was called by the remote client.
 395          */
 396         public function execute() {
 397                 if ( $this->mInternalMode ) {
 398                         $this->executeAction();
 399                 } else {
 400                         $this->executeActionWithErrorHandling();
 401                 }
 402         }
 403
 404         /**
 405          * Execute an action, and in case of an error, erase whatever partial results
 406          * have been accumulated, and replace it with an error message and a help screen.
 407          */
 408         protected function executeActionWithErrorHandling() {
 409                 // Verify the CORS header before executing the action
 410                 if ( !$this->handleCORS() ) {
 411                         // handleCORS() has sent a 403, abort
 412                         return;
 413                 }
 414
 415                 // Exit here if the request method was OPTIONS
 416                 // (assume there will be a followup GET or POST)
 417                 if ( $this->getRequest()->getMethod() === 'OPTIONS' ) {
 418                         return;
 419                 }
 420
 421                 // In case an error occurs during data output,
 422                 // clear the output buffer and print just the error information
 423                 $obLevel = ob_get_level();
 424                 ob_start();
 425
 426                 $t = microtime( true );
 427                 $isError = false;
 428                 try {
 429                         $this->executeAction();
 430                         $this->logRequest( microtime( true ) - $t );
 431
 432                 } catch ( Exception $e ) {
 433                         $this->handleException( $e );
 434                         $this->logRequest( microtime( true ) - $t, $e );
 435                         $isError = true;
 436                 }
 437
 438                 // Commit DBs and send any related cookies and headers
 439                 MediaWiki::preOutputCommit( $this->getContext() );
 440
 441                 // Send cache headers after any code which might generate an error, to
 442                 // avoid sending public cache headers for errors.
 443                 $this->sendCacheHeaders( $isError );
 444
 445                 // Executing the action might have already messed with the output
 446                 // buffers.
 447                 while ( ob_get_level() > $obLevel ) {
 448                         ob_end_flush();
 449                 }
 450         }
 451
 452         /**
 453          * Handle an exception as an API response
 454          *
 455          * @since 1.23
 456          * @param Exception $e
 457          */
 458         protected function handleException( Exception $e ) {
 459                 // Bug 63145: Rollback any open database transactions
 460                 if ( !( $e instanceof UsageException ) ) {
 461                         // UsageExceptions are intentional, so don't rollback if that's the case
 462                         try {
 463                                 MWExceptionHandler::rollbackMasterChangesAndLog( $e );
 464                         } catch ( DBError $e2 ) {
 465                                 // Rollback threw an exception too. Log it, but don't interrupt
 466                                 // our regularly scheduled exception handling.
 467                                 MWExceptionHandler::logException( $e2 );
 468                         }
 469                 }
 470
 471                 // Allow extra cleanup and logging
 472                 Hooks::run( 'ApiMain::onException', [ $this, $e ] );
 473
 474                 // Log it
 475                 if ( !( $e instanceof UsageException ) ) {
 476                         MWExceptionHandler::logException( $e );
 477                 }
 478
 479                 // Handle any kind of exception by outputting properly formatted error message.
 480                 // If this fails, an unhandled exception should be thrown so that global error
 481                 // handler will process and log it.
 482
 483                 $errCode = $this->substituteResultWithError( $e );
 484
 485                 // Error results should not be cached
 486                 $this->setCacheMode( 'private' );
 487
 488                 $response = $this->getRequest()->response();
 489                 $headerStr = 'MediaWiki-API-Error: ' . $errCode;
 490                 if ( $e->getCode() === 0 ) {
 491                         $response->header( $headerStr );
 492                 } else {
 493                         $response->header( $headerStr, true, $e->getCode() );
 494                 }
 495
 496                 // Reset and print just the error message
 497                 ob_clean();
 498
 499                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 500                 $this->createErrorPrinter();
 501
 502                 try {
 503                         $this->printResult( true );
 504                 } catch ( UsageException $ex ) {
 505                         // The error printer itself is failing. Try suppressing its request
 506                         // parameters and redo.
 507                         $this->setWarning(
 508                                 'Error printer failed (will retry without params): ' . $ex->getMessage()
 509                         );
 510                         $this->mPrinter = null;
 511                         $this->createErrorPrinter();
 512                         $this->mPrinter->forceDefaultParams();
 513                         $this->printResult( true );
 514                 }
 515         }
 516
 517         /**
 518          * Handle an exception from the ApiBeforeMain hook.
 519          *
 520          * This tries to print the exception as an API response, to be more
 521          * friendly to clients. If it fails, it will rethrow the exception.
 522          *
 523          * @since 1.23
 524          * @param Exception $e
 525          * @throws Exception
 526          */
 527         public static function handleApiBeforeMainException( Exception $e ) {
 528                 ob_start();
 529
 530                 try {
 531                         $main = new self( RequestContext::getMain(), false );
 532                         $main->handleException( $e );
 533                         $main->logRequest( 0, $e );
 534                 } catch ( Exception $e2 ) {
 535                         // Nope, even that didn't work. Punt.
 536                         throw $e;
 537                 }
 538
 539                 // Reset cache headers
 540                 $main->sendCacheHeaders( true );
 541
 542                 ob_end_flush();
 543         }
 544
 545         /**
 546          * Check the &origin= query parameter against the Origin: HTTP header and respond appropriately.
 547          *
 548          * If no origin parameter is present, nothing happens.
 549          * If an origin parameter is present but doesn't match the Origin header, a 403 status code
 550          * is set and false is returned.
 551          * If the parameter and the header do match, the header is checked against $wgCrossSiteAJAXdomains
 552          * and $wgCrossSiteAJAXdomainExceptions, and if the origin qualifies, the appropriate CORS
 553          * headers are set.
 554          * http://www.w3.org/TR/cors/#resource-requests
 555          * http://www.w3.org/TR/cors/#resource-preflight-requests
 556          *
 557          * @return bool False if the caller should abort (403 case), true otherwise (all other cases)
 558          */
 559         protected function handleCORS() {
 560                 $originParam = $this->getParameter( 'origin' ); // defaults to null
 561                 if ( $originParam === null ) {
 562                         // No origin parameter, nothing to do
 563                         return true;
 564                 }
 565
 566                 $request = $this->getRequest();
 567                 $response = $request->response();
 568
 569                 // Origin: header is a space-separated list of origins, check all of them
 570                 $originHeader = $request->getHeader( 'Origin' );
 571                 if ( $originHeader === false ) {
 572                         $origins = [];
 573                 } else {
 574                         $originHeader = trim( $originHeader );
 575                         $origins = preg_split( '/\s+/', $originHeader );
 576                 }
 577
 578                 if ( !in_array( $originParam, $origins ) ) {
 579                         // origin parameter set but incorrect
 580                         // Send a 403 response
 581                         $response->statusHeader( 403 );
 582                         $response->header( 'Cache-Control: no-cache' );
 583                         echo "'origin' parameter does not match Origin header\n";
 584
 585                         return false;
 586                 }
 587
 588                 $config = $this->getConfig();
 589                 $matchOrigin = count( $origins ) === 1 && self::matchOrigin(
 590                         $originParam,
 591                         $config->get( 'CrossSiteAJAXdomains' ),
 592                         $config->get( 'CrossSiteAJAXdomainExceptions' )
 593                 );
 594
 595                 if ( $matchOrigin ) {
 596                         $requestedMethod = $request->getHeader( 'Access-Control-Request-Method' );
 597                         $preflight = $request->getMethod() === 'OPTIONS' && $requestedMethod !== false;
 598                         if ( $preflight ) {
 599                                 // This is a CORS preflight request
 600                                 if ( $requestedMethod !== 'POST' && $requestedMethod !== 'GET' ) {
 601                                         // If method is not a case-sensitive match, do not set any additional headers and terminate.
 602                                         return true;
 603                                 }
 604                                 // We allow the actual request to send the following headers
 605                                 $requestedHeaders = $request->getHeader( 'Access-Control-Request-Headers' );
 606                                 if ( $requestedHeaders !== false ) {
 607                                         if ( !self::matchRequestedHeaders( $requestedHeaders ) ) {
 608                                                 return true;
 609                                         }
 610                                         $response->header( 'Access-Control-Allow-Headers: ' . $requestedHeaders );
 611                                 }
 612
 613                                 // We only allow the actual request to be GET or POST
 614                                 $response->header( 'Access-Control-Allow-Methods: POST, GET' );
 615                         }
 616
 617                         $response->header( "Access-Control-Allow-Origin: $originHeader" );
 618                         $response->header( 'Access-Control-Allow-Credentials: true' );
 619                         // http://www.w3.org/TR/resource-timing/#timing-allow-origin
 620                         $response->header( "Timing-Allow-Origin: $originHeader" );
 621
 622                         if ( !$preflight ) {
 623                                 $response->header(
 624                                         'Access-Control-Expose-Headers: MediaWiki-API-Error, Retry-After, X-Database-Lag'
 625                                 );
 626                         }
 627                 }
 628
 629                 $this->getOutput()->addVaryHeader( 'Origin' );
 630                 return true;
 631         }
 632
 633         /**
 634          * Attempt to match an Origin header against a set of rules and a set of exceptions
 635          * @param string $value Origin header
 636          * @param array $rules Set of wildcard rules
 637          * @param array $exceptions Set of wildcard rules
 638          * @return bool True if $value matches a rule in $rules and doesn't match
 639          *    any rules in $exceptions, false otherwise
 640          */
 641         protected static function matchOrigin( $value, $rules, $exceptions ) {
 642                 foreach ( $rules as $rule ) {
 643                         if ( preg_match( self::wildcardToRegex( $rule ), $value ) ) {
 644                                 // Rule matches, check exceptions
 645                                 foreach ( $exceptions as $exc ) {
 646                                         if ( preg_match( self::wildcardToRegex( $exc ), $value ) ) {
 647                                                 return false;
 648                                         }
 649                                 }
 650
 651                                 return true;
 652                         }
 653                 }
 654
 655                 return false;
 656         }
 657
 658         /**
 659          * Attempt to validate the value of Access-Control-Request-Headers against a list
 660          * of headers that we allow the follow up request to send.
 661          *
 662          * @param string $requestedHeaders Comma seperated list of HTTP headers
 663          * @return bool True if all requested headers are in the list of allowed headers
 664          */
 665         protected static function matchRequestedHeaders( $requestedHeaders ) {
 666                 if ( trim( $requestedHeaders ) === '' ) {
 667                         return true;
 668                 }
 669                 $requestedHeaders = explode( ',', $requestedHeaders );
 670                 $allowedAuthorHeaders = array_flip( [
 671                         /* simple headers (see spec) */
 672                         'accept',
 673                         'accept-language',
 674                         'content-language',
 675                         'content-type',
 676                         /* non-authorable headers in XHR, which are however requested by some UAs */
 677                         'accept-encoding',
 678                         'dnt',
 679                         'origin',
 680                         /* MediaWiki whitelist */
 681                         'api-user-agent',
 682                 ] );
 683                 foreach ( $requestedHeaders as $rHeader ) {
 684                         $rHeader = strtolower( trim( $rHeader ) );
 685                         if ( !isset( $allowedAuthorHeaders[$rHeader] ) ) {
 686                                 wfDebugLog( 'api', 'CORS preflight failed on requested header: ' . $rHeader );
 687                                 return false;
 688                         }
 689                 }
 690                 return true;
 691         }
 692
 693         /**
 694          * Helper function to convert wildcard string into a regex
 695          * '*' => '.*?'
 696          * '?' => '.'
 697          *
 698          * @param string $wildcard String with wildcards
 699          * @return string Regular expression
 700          */
 701         protected static function wildcardToRegex( $wildcard ) {
 702                 $wildcard = preg_quote( $wildcard, '/' );
 703                 $wildcard = str_replace(
 704                         [ '\*', '\?' ],
 705                         [ '.*?', '.' ],
 706                         $wildcard
 707                 );
 708
 709                 return "/^https?:\/\/$wildcard$/";
 710         }
 711
 712         /**
 713          * Send caching headers
 714          * @param boolean $isError Whether an error response is being output
 715          * @since 1.26 added $isError parameter
 716          */
 717         protected function sendCacheHeaders( $isError ) {
 718                 $response = $this->getRequest()->response();
 719                 $out = $this->getOutput();
 720
 721                 $config = $this->getConfig();
 722
 723                 if ( $config->get( 'VaryOnXFP' ) ) {
 724                         $out->addVaryHeader( 'X-Forwarded-Proto' );
 725                 }
 726
 727                 if ( !$isError && $this->mModule &&
 728                         ( $this->getRequest()->getMethod() === 'GET' || $this->getRequest()->getMethod() === 'HEAD' )
 729                 ) {
 730                         $etag = $this->mModule->getConditionalRequestData( 'etag' );
 731                         if ( $etag !== null ) {
 732                                 $response->header( "ETag: $etag" );
 733                         }
 734                         $lastMod = $this->mModule->getConditionalRequestData( 'last-modified' );
 735                         if ( $lastMod !== null ) {
 736                                 $response->header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $lastMod ) );
 737                         }
 738                 }
 739
 740                 // The logic should be:
 741                 // $this->mCacheControl['max-age'] is set?
 742                 //    Use it, the module knows better than our guess.
 743                 // !$this->mModule || $this->mModule->isWriteMode(), and mCacheMode is private?
 744                 //    Use 0 because we can guess caching is probably the wrong thing to do.
 745                 // Use $this->getParameter( 'maxage' ), which already defaults to 0.
 746                 $maxage = 0;
 747                 if ( isset( $this->mCacheControl['max-age'] ) ) {
 748                         $maxage = $this->mCacheControl['max-age'];
 749                 } elseif ( ( $this->mModule && !$this->mModule->isWriteMode() ) ||
 750                         $this->mCacheMode !== 'private'
 751                 ) {
 752                         $maxage = $this->getParameter( 'maxage' );
 753                 }
 754                 $privateCache = 'private, must-revalidate, max-age=' . $maxage;
 755
 756                 if ( $this->mCacheMode == 'private' ) {
 757                         $response->header( "Cache-Control: $privateCache" );
 758                         return;
 759                 }
 760
 761                 $useKeyHeader = $config->get( 'UseKeyHeader' );
 762                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 763                         $out->addVaryHeader( 'Cookie' );
 764                         $response->header( $out->getVaryHeader() );
 765                         if ( $useKeyHeader ) {
 766                                 $response->header( $out->getKeyHeader() );
 767                                 if ( $out->haveCacheVaryCookies() ) {
 768                                         // Logged in, mark this request private
 769                                         $response->header( "Cache-Control: $privateCache" );
 770                                         return;
 771                                 }
 772                                 // Logged out, send normal public headers below
 773                         } elseif ( MediaWiki\Session\SessionManager::getGlobalSession()->isPersistent() ) {
 774                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 775                                 // Mark request private
 776                                 $response->header( "Cache-Control: $privateCache" );
 777
 778                                 return;
 779                         } // else no Key and anonymous, send public headers below
 780                 }
 781
 782                 // Send public headers
 783                 $response->header( $out->getVaryHeader() );
 784                 if ( $useKeyHeader ) {
 785                         $response->header( $out->getKeyHeader() );
 786                 }
 787
 788                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 789                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 790                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 791                 }
 792                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 793                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 794                 }
 795
 796                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 797                         // Public cache not requested
 798                         // Sending a Vary header in this case is harmless, and protects us
 799                         // against conditional calls of setCacheMaxAge().
 800                         $response->header( "Cache-Control: $privateCache" );
 801
 802                         return;
 803                 }
 804
 805                 $this->mCacheControl['public'] = true;
 806
 807                 // Send an Expires header
 808                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 809                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 810                 $response->header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 811
 812                 // Construct the Cache-Control header
 813                 $ccHeader = '';
 814                 $separator = '';
 815                 foreach ( $this->mCacheControl as $name => $value ) {
 816                         if ( is_bool( $value ) ) {
 817                                 if ( $value ) {
 818                                         $ccHeader .= $separator . $name;
 819                                         $separator = ', ';
 820                                 }
 821                         } else {
 822                                 $ccHeader .= $separator . "$name=$value";
 823                                 $separator = ', ';
 824                         }
 825                 }
 826
 827                 $response->header( "Cache-Control: $ccHeader" );
 828         }
 829
 830         /**
 831          * Create the printer for error output
 832          */
 833         private function createErrorPrinter() {
 834                 if ( !isset( $this->mPrinter ) ) {
 835                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 836                         if ( !$this->mModuleMgr->isDefined( $value, 'format' ) ) {
 837                                 $value = self::API_DEFAULT_FORMAT;
 838                         }
 839                         $this->mPrinter = $this->createPrinterByName( $value );
 840                 }
 841
 842                 // Printer may not be able to handle errors. This is particularly
 843                 // likely if the module returns something for getCustomPrinter().
 844                 if ( !$this->mPrinter->canPrintErrors() ) {
 845                         $this->mPrinter = $this->createPrinterByName( self::API_DEFAULT_FORMAT );
 846                 }
 847         }
 848
 849         /**
 850          * Create an error message for the given exception.
 851          *
 852          * If the exception is a UsageException then
 853          * UsageException::getMessageArray() will be called to create the message.
 854          *
 855          * @param Exception $e
 856          * @return array ['code' => 'some string', 'info' => 'some other string']
 857          * @since 1.27
 858          */
 859         protected function errorMessageFromException( $e ) {
 860                 if ( $e instanceof UsageException ) {
 861                         // User entered incorrect parameters - generate error response
 862                         $errMessage = $e->getMessageArray();
 863                 } else {
 864                         // Something is seriously wrong
 865                         if ( ( $e instanceof DBQueryError ) && !$config->get( 'ShowSQLErrors' ) ) {
 866                                 $info = 'Database query error';
 867                         } else {
 868                                 $info = "Exception Caught: {$e->getMessage()}";
 869                         }
 870
 871                         $errMessage = [
 872                                 'code' => 'internal_api_error_' . get_class( $e ),
 873                                 'info' => '[' . MWExceptionHandler::getLogId( $e ) . '] ' . $info,
 874                         ];
 875                 }
 876                 return $errMessage;
 877         }
 878
 879         /**
 880          * Replace the result data with the information about an exception.
 881          * Returns the error code
 882          * @param Exception $e
 883          * @return string
 884          */
 885         protected function substituteResultWithError( $e ) {
 886                 $result = $this->getResult();
 887                 $config = $this->getConfig();
 888
 889                 $errMessage = $this->errorMessageFromException( $e );
 890                 if ( $e instanceof UsageException ) {
 891                         // User entered incorrect parameters - generate error response
 892                         $link = wfExpandUrl( wfScript( 'api' ) );
 893                         ApiResult::setContentValue( $errMessage, 'docref', "See $link for API usage" );
 894                 } else {
 895                         // Something is seriously wrong
 896                         if ( $config->get( 'ShowExceptionDetails' ) ) {
 897                                 ApiResult::setContentValue(
 898                                         $errMessage,
 899                                         'trace',
 900                                         MWExceptionHandler::getRedactedTraceAsString( $e )
 901                                 );
 902                         }
 903                 }
 904
 905                 // Remember all the warnings to re-add them later
 906                 $warnings = $result->getResultData( [ 'warnings' ] );
 907
 908                 $result->reset();
 909                 // Re-add the id
 910                 $requestid = $this->getParameter( 'requestid' );
 911                 if ( !is_null( $requestid ) ) {
 912                         $result->addValue( null, 'requestid', $requestid, ApiResult::NO_SIZE_CHECK );
 913                 }
 914                 if ( $config->get( 'ShowHostnames' ) ) {
 915                         // servedby is especially useful when debugging errors
 916                         $result->addValue( null, 'servedby', wfHostname(), ApiResult::NO_SIZE_CHECK );
 917                 }
 918                 if ( $warnings !== null ) {
 919                         $result->addValue( null, 'warnings', $warnings, ApiResult::NO_SIZE_CHECK );
 920                 }
 921
 922                 $result->addValue( null, 'error', $errMessage, ApiResult::NO_SIZE_CHECK );
 923
 924                 return $errMessage['code'];
 925         }
 926
 927         /**
 928          * Set up for the execution.
 929          * @return array
 930          */
 931         protected function setupExecuteAction() {
 932                 // First add the id to the top element
 933                 $result = $this->getResult();
 934                 $requestid = $this->getParameter( 'requestid' );
 935                 if ( !is_null( $requestid ) ) {
 936                         $result->addValue( null, 'requestid', $requestid );
 937                 }
 938
 939                 if ( $this->getConfig()->get( 'ShowHostnames' ) ) {
 940                         $servedby = $this->getParameter( 'servedby' );
 941                         if ( $servedby ) {
 942                                 $result->addValue( null, 'servedby', wfHostname() );
 943                         }
 944                 }
 945
 946                 if ( $this->getParameter( 'curtimestamp' ) ) {
 947                         $result->addValue( null, 'curtimestamp', wfTimestamp( TS_ISO_8601, time() ),
 948                                 ApiResult::NO_SIZE_CHECK );
 949                 }
 950
 951                 $params = $this->extractRequestParams();
 952
 953                 $this->mAction = $params['action'];
 954
 955                 if ( !is_string( $this->mAction ) ) {
 956                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 957                 }
 958
 959                 return $params;
 960         }
 961
 962         /**
 963          * Set up the module for response
 964          * @return ApiBase The module that will handle this action
 965          * @throws MWException
 966          * @throws UsageException
 967          */
 968         protected function setupModule() {
 969                 // Instantiate the module requested by the user
 970                 $module = $this->mModuleMgr->getModule( $this->mAction, 'action' );
 971                 if ( $module === null ) {
 972                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 973                 }
 974                 $moduleParams = $module->extractRequestParams();
 975
 976                 // Check token, if necessary
 977                 if ( $module->needsToken() === true ) {
 978                         throw new MWException(
 979                                 "Module '{$module->getModuleName()}' must be updated for the new token handling. " .
 980                                 "See documentation for ApiBase::needsToken for details."
 981                         );
 982                 }
 983                 if ( $module->needsToken() ) {
 984                         if ( !$module->mustBePosted() ) {
 985                                 throw new MWException(
 986                                         "Module '{$module->getModuleName()}' must require POST to use tokens."
 987                                 );
 988                         }
 989
 990                         if ( !isset( $moduleParams['token'] ) ) {
 991                                 $this->dieUsageMsg( [ 'missingparam', 'token' ] );
 992                         }
 993
 994                         if ( !$this->getConfig()->get( 'DebugAPI' ) &&
 995                                 array_key_exists(
 996                                         $module->encodeParamName( 'token' ),
 997                                         $this->getRequest()->getQueryValues()
 998                                 )
 999                         ) {
1000                                 $this->dieUsage(
1001                                         "The '{$module->encodeParamName( 'token' )}' parameter was " .
1002                                                 'found in the query string, but must be in the POST body',
1003                                         'mustposttoken'
1004                                 );
1005                         }
1006
1007                         if ( !$module->validateToken( $moduleParams['token'], $moduleParams ) ) {
1008                                 $this->dieUsageMsg( 'sessionfailure' );
1009                         }
1010                 }
1011
1012                 return $module;
1013         }
1014
1015         /**
1016          * Check the max lag if necessary
1017          * @param ApiBase $module Api module being used
1018          * @param array $params Array an array containing the request parameters.
1019          * @return bool True on success, false should exit immediately
1020          */
1021         protected function checkMaxLag( $module, $params ) {
1022                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
1023                         $maxLag = $params['maxlag'];
1024                         list( $host, $lag ) = wfGetLB()->getMaxLag();
1025                         if ( $lag > $maxLag ) {
1026                                 $response = $this->getRequest()->response();
1027
1028                                 $response->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
1029                                 $response->header( 'X-Database-Lag: ' . intval( $lag ) );
1030
1031                                 if ( $this->getConfig()->get( 'ShowHostnames' ) ) {
1032                                         $this->dieUsage( "Waiting for $host: $lag seconds lagged", 'maxlag' );
1033                                 }
1034
1035                                 $this->dieUsage( "Waiting for a database server: $lag seconds lagged", 'maxlag' );
1036                         }
1037                 }
1038
1039                 return true;
1040         }
1041
1042         /**
1043          * Check selected RFC 7232 precondition headers
1044          *
1045          * RFC 7232 envisions a particular model where you send your request to "a
1046          * resource", and for write requests that you can read "the resource" by
1047          * changing the method to GET. When the API receives a GET request, it
1048          * works out even though "the resource" from RFC 7232's perspective might
1049          * be many resources from MediaWiki's perspective. But it totally fails for
1050          * a POST, since what HTTP sees as "the resource" is probably just
1051          * "/api.php" with all the interesting bits in the body.
1052          *
1053          * Therefore, we only support RFC 7232 precondition headers for GET (and
1054          * HEAD). That means we don't need to bother with If-Match and
1055          * If-Unmodified-Since since they only apply to modification requests.
1056          *
1057          * And since we don't support Range, If-Range is ignored too.
1058          *
1059          * @since 1.26
1060          * @param ApiBase $module Api module being used
1061          * @return bool True on success, false should exit immediately
1062          */
1063         protected function checkConditionalRequestHeaders( $module ) {
1064                 if ( $this->mInternalMode ) {
1065                         // No headers to check in internal mode
1066                         return true;
1067                 }
1068
1069                 if ( $this->getRequest()->getMethod() !== 'GET' && $this->getRequest()->getMethod() !== 'HEAD' ) {
1070                         // Don't check POSTs
1071                         return true;
1072                 }
1073
1074                 $return304 = false;
1075
1076                 $ifNoneMatch = array_diff(
1077                         $this->getRequest()->getHeader( 'If-None-Match', WebRequest::GETHEADER_LIST ) ?: [],
1078                         [ '' ]
1079                 );
1080                 if ( $ifNoneMatch ) {
1081                         if ( $ifNoneMatch === [ '*' ] ) {
1082                                 // API responses always "exist"
1083                                 $etag = '*';
1084                         } else {
1085                                 $etag = $module->getConditionalRequestData( 'etag' );
1086                         }
1087                 }
1088                 if ( $ifNoneMatch && $etag !== null ) {
1089                         $test = substr( $etag, 0, 2 ) === 'W/' ? substr( $etag, 2 ) : $etag;
1090                         $match = array_map( function ( $s ) {
1091                                 return substr( $s, 0, 2 ) === 'W/' ? substr( $s, 2 ) : $s;
1092                         }, $ifNoneMatch );
1093                         $return304 = in_array( $test, $match, true );
1094                 } else {
1095                         $value = trim( $this->getRequest()->getHeader( 'If-Modified-Since' ) );
1096
1097                         // Some old browsers sends sizes after the date, like this:
1098                         //  Wed, 20 Aug 2003 06:51:19 GMT; length=5202
1099                         // Ignore that.
1100                         $i = strpos( $value, ';' );
1101                         if ( $i !== false ) {
1102                                 $value = trim( substr( $value, 0, $i ) );
1103                         }
1104
1105                         if ( $value !== '' ) {
1106                                 try {
1107                                         $ts = new MWTimestamp( $value );
1108                                         if (
1109                                                 // RFC 7231 IMF-fixdate
1110                                                 $ts->getTimestamp( TS_RFC2822 ) === $value ||
1111                                                 // RFC 850
1112                                                 $ts->format( 'l, d-M-y H:i:s' ) . ' GMT' === $value ||
1113                                                 // asctime (with and without space-padded day)
1114                                                 $ts->format( 'D M j H:i:s Y' ) === $value ||
1115                                                 $ts->format( 'D M  j H:i:s Y' ) === $value
1116                                         ) {
1117                                                 $lastMod = $module->getConditionalRequestData( 'last-modified' );
1118                                                 if ( $lastMod !== null ) {
1119                                                         // Mix in some MediaWiki modification times
1120                                                         $modifiedTimes = [
1121                                                                 'page' => $lastMod,
1122                                                                 'user' => $this->getUser()->getTouched(),
1123                                                                 'epoch' => $this->getConfig()->get( 'CacheEpoch' ),
1124                                                         ];
1125                                                         if ( $this->getConfig()->get( 'UseSquid' ) ) {
1126                                                                 // T46570: the core page itself may not change, but resources might
1127                                                                 $modifiedTimes['sepoch'] = wfTimestamp(
1128                                                                         TS_MW, time() - $this->getConfig()->get( 'SquidMaxage' )
1129                                                                 );
1130                                                         }
1131                                                         Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes ] );
1132                                                         $lastMod = max( $modifiedTimes );
1133                                                         $return304 = wfTimestamp( TS_MW, $lastMod ) <= $ts->getTimestamp( TS_MW );
1134                                                 }
1135                                         }
1136                                 } catch ( TimestampException $e ) {
1137                                         // Invalid timestamp, ignore it
1138                                 }
1139                         }
1140                 }
1141
1142                 if ( $return304 ) {
1143                         $this->getRequest()->response()->statusHeader( 304 );
1144
1145                         // Avoid outputting the compressed representation of a zero-length body
1146                         MediaWiki\suppressWarnings();
1147                         ini_set( 'zlib.output_compression', 0 );
1148                         MediaWiki\restoreWarnings();
1149                         wfClearOutputBuffers();
1150
1151                         return false;
1152                 }
1153
1154                 return true;
1155         }
1156
1157         /**
1158          * Check for sufficient permissions to execute
1159          * @param ApiBase $module An Api module
1160          */
1161         protected function checkExecutePermissions( $module ) {
1162                 $user = $this->getUser();
1163                 if ( $module->isReadMode() && !User::isEveryoneAllowed( 'read' ) &&
1164                         !$user->isAllowed( 'read' )
1165                 ) {
1166                         $this->dieUsageMsg( 'readrequired' );
1167                 }
1168
1169                 if ( $module->isWriteMode() ) {
1170                         if ( !$this->mEnableWrite ) {
1171                                 $this->dieUsageMsg( 'writedisabled' );
1172                         } elseif ( !$user->isAllowed( 'writeapi' ) ) {
1173                                 $this->dieUsageMsg( 'writerequired' );
1174                         } elseif ( $this->getRequest()->getHeader( 'Promise-Non-Write-API-Action' ) ) {
1175                                 $this->dieUsage(
1176                                         "Promise-Non-Write-API-Action HTTP header cannot be sent to write API modules",
1177                                         'promised-nonwrite-api'
1178                                 );
1179                         }
1180
1181                         $this->checkReadOnly( $module );
1182                 }
1183
1184                 // Allow extensions to stop execution for arbitrary reasons.
1185                 $message = false;
1186                 if ( !Hooks::run( 'ApiCheckCanExecute', [ $module, $user, &$message ] ) ) {
1187                         $this->dieUsageMsg( $message );
1188                 }
1189         }
1190
1191         /**
1192          * Check if the DB is read-only for this user
1193          * @param ApiBase $module An Api module
1194          */
1195         protected function checkReadOnly( $module ) {
1196                 if ( wfReadOnly() ) {
1197                         $this->dieReadOnly();
1198                 }
1199
1200                 if ( $module->isWriteMode()
1201                         && in_array( 'bot', $this->getUser()->getGroups() )
1202                         && wfGetLB()->getServerCount() > 1
1203                 ) {
1204                         $this->checkBotReadOnly();
1205                 }
1206         }
1207
1208         /**
1209          * Check whether we are readonly for bots
1210          */
1211         private function checkBotReadOnly() {
1212                 // Figure out how many servers have passed the lag threshold
1213                 $numLagged = 0;
1214                 $lagLimit = $this->getConfig()->get( 'APIMaxLagThreshold' );
1215                 $laggedServers = [];
1216                 $loadBalancer = wfGetLB();
1217                 foreach ( $loadBalancer->getLagTimes() as $serverIndex => $lag ) {
1218                         if ( $lag > $lagLimit ) {
1219                                 ++$numLagged;
1220                                 $laggedServers[] = $loadBalancer->getServerName( $serverIndex ) . " ({$lag}s)";
1221                         }
1222                 }
1223
1224                 // If a majority of slaves are too lagged then disallow writes
1225                 $slaveCount = wfGetLB()->getServerCount() - 1;
1226                 if ( $numLagged >= ceil( $slaveCount / 2 ) ) {
1227                         $laggedServers = join( ', ', $laggedServers );
1228                         wfDebugLog(
1229                                 'api-readonly',
1230                                 "Api request failed as read only because the following DBs are lagged: $laggedServers"
1231                         );
1232
1233                         $parsed = $this->parseMsg( [ 'readonlytext' ] );
1234                         $this->dieUsage(
1235                                 $parsed['info'],
1236                                 $parsed['code'],
1237                                 /* http error */
1238                                 0,
1239                                 [ 'readonlyreason' => "Waiting for $numLagged lagged database(s)" ]
1240                         );
1241                 }
1242         }
1243
1244         /**
1245          * Check asserts of the user's rights
1246          * @param array $params
1247          */
1248         protected function checkAsserts( $params ) {
1249                 if ( isset( $params['assert'] ) ) {
1250                         $user = $this->getUser();
1251                         switch ( $params['assert'] ) {
1252                                 case 'user':
1253                                         if ( $user->isAnon() ) {
1254                                                 $this->dieUsage( 'Assertion that the user is logged in failed', 'assertuserfailed' );
1255                                         }
1256                                         break;
1257                                 case 'bot':
1258                                         if ( !$user->isAllowed( 'bot' ) ) {
1259                                                 $this->dieUsage( 'Assertion that the user has the bot right failed', 'assertbotfailed' );
1260                                         }
1261                                         break;
1262                         }
1263                 }
1264         }
1265
1266         /**
1267          * Check POST for external response and setup result printer
1268          * @param ApiBase $module An Api module
1269          * @param array $params An array with the request parameters
1270          */
1271         protected function setupExternalResponse( $module, $params ) {
1272                 $request = $this->getRequest();
1273                 if ( !$request->wasPosted() && $module->mustBePosted() ) {
1274                         // Module requires POST. GET request might still be allowed
1275                         // if $wgDebugApi is true, otherwise fail.
1276                         $this->dieUsageMsgOrDebug( [ 'mustbeposted', $this->mAction ] );
1277                 }
1278
1279                 // See if custom printer is used
1280                 $this->mPrinter = $module->getCustomPrinter();
1281                 if ( is_null( $this->mPrinter ) ) {
1282                         // Create an appropriate printer
1283                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
1284                 }
1285
1286                 if ( $request->getProtocol() === 'http' && (
1287                         $request->getSession()->shouldForceHTTPS() ||
1288                         ( $this->getUser()->isLoggedIn() &&
1289                                 $this->getUser()->requiresHTTPS() )
1290                 ) ) {
1291                         $this->logFeatureUsage( 'https-expected' );
1292                         $this->setWarning( 'HTTP used when HTTPS was expected' );
1293                 }
1294         }
1295
1296         /**
1297          * Execute the actual module, without any error handling
1298          */
1299         protected function executeAction() {
1300                 $params = $this->setupExecuteAction();
1301                 $module = $this->setupModule();
1302                 $this->mModule = $module;
1303
1304                 if ( !$this->mInternalMode ) {
1305                         $this->setRequestExpectations( $module );
1306                 }
1307
1308                 $this->checkExecutePermissions( $module );
1309
1310                 if ( !$this->checkMaxLag( $module, $params ) ) {
1311                         return;
1312                 }
1313
1314                 if ( !$this->checkConditionalRequestHeaders( $module ) ) {
1315                         return;
1316                 }
1317
1318                 if ( !$this->mInternalMode ) {
1319                         $this->setupExternalResponse( $module, $params );
1320                 }
1321
1322                 $this->checkAsserts( $params );
1323
1324                 // Execute
1325                 $module->execute();
1326                 Hooks::run( 'APIAfterExecute', [ &$module ] );
1327
1328                 $this->reportUnusedParams();
1329
1330                 if ( !$this->mInternalMode ) {
1331                         // append Debug information
1332                         MWDebug::appendDebugInfoToApiResult( $this->getContext(), $this->getResult() );
1333
1334                         // Print result data
1335                         $this->printResult( false );
1336                 }
1337         }
1338
1339         /**
1340          * Set database connection, query, and write expectations given this module request
1341          * @param ApiBase $module
1342          */
1343         protected function setRequestExpectations( ApiBase $module ) {
1344                 $limits = $this->getConfig()->get( 'TrxProfilerLimits' );
1345                 $trxProfiler = Profiler::instance()->getTransactionProfiler();
1346                 if ( $this->getRequest()->wasPosted() ) {
1347                         if ( $module->isWriteMode() ) {
1348                                 $trxProfiler->setExpectations( $limits['POST'], __METHOD__ );
1349                         } else {
1350                                 $trxProfiler->setExpectations( $limits['POST-nonwrite'], __METHOD__ );
1351                         }
1352                 } else {
1353                         $trxProfiler->setExpectations( $limits['GET'], __METHOD__ );
1354                 }
1355         }
1356
1357         /**
1358          * Log the preceding request
1359          * @param float $time Time in seconds
1360          * @param Exception $e Exception caught while processing the request
1361          */
1362         protected function logRequest( $time, $e = null ) {
1363                 $request = $this->getRequest();
1364                 $logCtx = [
1365                         'ts' => time(),
1366                         'ip' => $request->getIP(),
1367                         'userAgent' => $this->getUserAgent(),
1368                         'wiki' => wfWikiID(),
1369                         'timeSpentBackend' => round( $time * 1000 ),
1370                         'hadError' => $e !== null,
1371                         'errorCodes' => [],
1372                         'params' => [],
1373                 ];
1374
1375                 if ( $e ) {
1376                         $logCtx['errorCodes'][] = $this->errorMessageFromException( $e )['code'];
1377                 }
1378
1379                 // Construct space separated message for 'api' log channel
1380                 $msg = "API {$request->getMethod()} " .
1381                         wfUrlencode( str_replace( ' ', '_', $this->getUser()->getName() ) ) .
1382                         " {$logCtx['ip']} " .
1383                         "T={$logCtx['timeSpentBackend']}ms";
1384
1385                 foreach ( $this->getParamsUsed() as $name ) {
1386                         $value = $request->getVal( $name );
1387                         if ( $value === null ) {
1388                                 continue;
1389                         }
1390
1391                         if ( strlen( $value ) > 256 ) {
1392                                 $value = substr( $value, 0, 256 );
1393                                 $encValue = $this->encodeRequestLogValue( $value ) . '[...]';
1394                         } else {
1395                                 $encValue = $this->encodeRequestLogValue( $value );
1396                         }
1397
1398                         $logCtx['params'][$name] = $value;
1399                         $msg .= " {$name}={$encValue}";
1400                 }
1401
1402                 wfDebugLog( 'api', $msg, 'private' );
1403                 // ApiRequest channel is for structured data consumers
1404                 wfDebugLog( 'ApiRequest', '', 'private', $logCtx );
1405         }
1406
1407         /**
1408          * Encode a value in a format suitable for a space-separated log line.
1409          * @param string $s
1410          * @return string
1411          */
1412         protected function encodeRequestLogValue( $s ) {
1413                 static $table;
1414                 if ( !$table ) {
1415                         $chars = ';@$!*(),/:';
1416                         $numChars = strlen( $chars );
1417                         for ( $i = 0; $i < $numChars; $i++ ) {
1418                                 $table[rawurlencode( $chars[$i] )] = $chars[$i];
1419                         }
1420                 }
1421
1422                 return strtr( rawurlencode( $s ), $table );
1423         }
1424
1425         /**
1426          * Get the request parameters used in the course of the preceding execute() request
1427          * @return array
1428          */
1429         protected function getParamsUsed() {
1430                 return array_keys( $this->mParamsUsed );
1431         }
1432
1433         /**
1434          * Get a request value, and register the fact that it was used, for logging.
1435          * @param string $name
1436          * @param mixed $default
1437          * @return mixed
1438          */
1439         public function getVal( $name, $default = null ) {
1440                 $this->mParamsUsed[$name] = true;
1441
1442                 $ret = $this->getRequest()->getVal( $name );
1443                 if ( $ret === null ) {
1444                         if ( $this->getRequest()->getArray( $name ) !== null ) {
1445                                 // See bug 10262 for why we don't just join( '|', ... ) the
1446                                 // array.
1447                                 $this->setWarning(
1448                                         "Parameter '$name' uses unsupported PHP array syntax"
1449                                 );
1450                         }
1451                         $ret = $default;
1452                 }
1453                 return $ret;
1454         }
1455
1456         /**
1457          * Get a boolean request value, and register the fact that the parameter
1458          * was used, for logging.
1459          * @param string $name
1460          * @return bool
1461          */
1462         public function getCheck( $name ) {
1463                 return $this->getVal( $name, null ) !== null;
1464         }
1465
1466         /**
1467          * Get a request upload, and register the fact that it was used, for logging.
1468          *
1469          * @since 1.21
1470          * @param string $name Parameter name
1471          * @return WebRequestUpload
1472          */
1473         public function getUpload( $name ) {
1474                 $this->mParamsUsed[$name] = true;
1475
1476                 return $this->getRequest()->getUpload( $name );
1477         }
1478
1479         /**
1480          * Report unused parameters, so the client gets a hint in case it gave us parameters we don't know,
1481          * for example in case of spelling mistakes or a missing 'g' prefix for generators.
1482          */
1483         protected function reportUnusedParams() {
1484                 $paramsUsed = $this->getParamsUsed();
1485                 $allParams = $this->getRequest()->getValueNames();
1486
1487                 if ( !$this->mInternalMode ) {
1488                         // Printer has not yet executed; don't warn that its parameters are unused
1489                         $printerParams = array_map(
1490                                 [ $this->mPrinter, 'encodeParamName' ],
1491                                 array_keys( $this->mPrinter->getFinalParams() ?: [] )
1492                         );
1493                         $unusedParams = array_diff( $allParams, $paramsUsed, $printerParams );
1494                 } else {
1495                         $unusedParams = array_diff( $allParams, $paramsUsed );
1496                 }
1497
1498                 if ( count( $unusedParams ) ) {
1499                         $s = count( $unusedParams ) > 1 ? 's' : '';
1500                         $this->setWarning( "Unrecognized parameter$s: '" . implode( $unusedParams, "', '" ) . "'" );
1501                 }
1502         }
1503
1504         /**
1505          * Print results using the current printer
1506          *
1507          * @param bool $isError
1508          */
1509         protected function printResult( $isError ) {
1510                 if ( $this->getConfig()->get( 'DebugAPI' ) !== false ) {
1511                         $this->setWarning( 'SECURITY WARNING: $wgDebugAPI is enabled' );
1512                 }
1513
1514                 $printer = $this->mPrinter;
1515                 $printer->initPrinter( false );
1516                 $printer->execute();
1517                 $printer->closePrinter();
1518         }
1519
1520         /**
1521          * @return bool
1522          */
1523         public function isReadMode() {
1524                 return false;
1525         }
1526
1527         /**
1528          * See ApiBase for description.
1529          *
1530          * @return array
1531          */
1532         public function getAllowedParams() {
1533                 return [
1534                         'action' => [
1535                                 ApiBase::PARAM_DFLT => 'help',
1536                                 ApiBase::PARAM_TYPE => 'submodule',
1537                         ],
1538                         'format' => [
1539                                 ApiBase::PARAM_DFLT => ApiMain::API_DEFAULT_FORMAT,
1540                                 ApiBase::PARAM_TYPE => 'submodule',
1541                         ],
1542                         'maxlag' => [
1543                                 ApiBase::PARAM_TYPE => 'integer'
1544                         ],
1545                         'smaxage' => [
1546                                 ApiBase::PARAM_TYPE => 'integer',
1547                                 ApiBase::PARAM_DFLT => 0
1548                         ],
1549                         'maxage' => [
1550                                 ApiBase::PARAM_TYPE => 'integer',
1551                                 ApiBase::PARAM_DFLT => 0
1552                         ],
1553                         'assert' => [
1554                                 ApiBase::PARAM_TYPE => [ 'user', 'bot' ]
1555                         ],
1556                         'requestid' => null,
1557                         'servedby' => false,
1558                         'curtimestamp' => false,
1559                         'origin' => null,
1560                         'uselang' => [
1561                                 ApiBase::PARAM_DFLT => 'user',
1562                         ],
1563                 ];
1564         }
1565
1566         /** @see ApiBase::getExamplesMessages() */
1567         protected function getExamplesMessages() {
1568                 return [
1569                         'action=help'
1570                                 => 'apihelp-help-example-main',
1571                         'action=help&recursivesubmodules=1'
1572                                 => 'apihelp-help-example-recursive',
1573                 ];
1574         }
1575
1576         public function modifyHelp( array &$help, array $options, array &$tocData ) {
1577                 // Wish PHP had an "array_insert_before". Instead, we have to manually
1578                 // reindex the array to get 'permissions' in the right place.
1579                 $oldHelp = $help;
1580                 $help = [];
1581                 foreach ( $oldHelp as $k => $v ) {
1582                         if ( $k === 'submodules' ) {
1583                                 $help['permissions'] = '';
1584                         }
1585                         $help[$k] = $v;
1586                 }
1587                 $help['datatypes'] = '';
1588                 $help['credits'] = '';
1589
1590                 // Fill 'permissions'
1591                 $help['permissions'] .= Html::openElement( 'div',
1592                         [ 'class' => 'apihelp-block apihelp-permissions' ] );
1593                 $m = $this->msg( 'api-help-permissions' );
1594                 if ( !$m->isDisabled() ) {
1595                         $help['permissions'] .= Html::rawElement( 'div', [ 'class' => 'apihelp-block-head' ],
1596                                 $m->numParams( count( self::$mRights ) )->parse()
1597                         );
1598                 }
1599                 $help['permissions'] .= Html::openElement( 'dl' );
1600                 foreach ( self::$mRights as $right => $rightMsg ) {
1601                         $help['permissions'] .= Html::element( 'dt', null, $right );
1602
1603                         $rightMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )->parse();
1604                         $help['permissions'] .= Html::rawElement( 'dd', null, $rightMsg );
1605
1606                         $groups = array_map( function ( $group ) {
1607                                 return $group == '*' ? 'all' : $group;
1608                         }, User::getGroupsWithPermission( $right ) );
1609
1610                         $help['permissions'] .= Html::rawElement( 'dd', null,
1611                                 $this->msg( 'api-help-permissions-granted-to' )
1612                                         ->numParams( count( $groups ) )
1613                                         ->params( $this->getLanguage()->commaList( $groups ) )
1614                                         ->parse()
1615                         );
1616                 }
1617                 $help['permissions'] .= Html::closeElement( 'dl' );
1618                 $help['permissions'] .= Html::closeElement( 'div' );
1619
1620                 // Fill 'datatypes' and 'credits', if applicable
1621                 if ( empty( $options['nolead'] ) ) {
1622                         $level = $options['headerlevel'];
1623                         $tocnumber = &$options['tocnumber'];
1624
1625                         $header = $this->msg( 'api-help-datatypes-header' )->parse();
1626                         $help['datatypes'] .= Html::rawElement( 'h' . min( 6, $level ),
1627                                 [ 'id' => 'main/datatypes', 'class' => 'apihelp-header' ],
1628                                 Html::element( 'span', [ 'id' => Sanitizer::escapeId( 'main/datatypes' ) ] ) .
1629                                 $header
1630                         );
1631                         $help['datatypes'] .= $this->msg( 'api-help-datatypes' )->parseAsBlock();
1632                         if ( !isset( $tocData['main/datatypes'] ) ) {
1633                                 $tocnumber[$level]++;
1634                                 $tocData['main/datatypes'] = [
1635                                         'toclevel' => count( $tocnumber ),
1636                                         'level' => $level,
1637                                         'anchor' => 'main/datatypes',
1638                                         'line' => $header,
1639                                         'number' => join( '.', $tocnumber ),
1640                                         'index' => false,
1641                                 ];
1642                         }
1643
1644                         $header = $this->msg( 'api-credits-header' )->parse();
1645                         $help['credits'] .= Html::rawElement( 'h' . min( 6, $level ),
1646                                 [ 'id' => 'main/credits', 'class' => 'apihelp-header' ],
1647                                 Html::element( 'span', [ 'id' => Sanitizer::escapeId( 'main/credits' ) ] ) .
1648                                 $header
1649                         );
1650                         $help['credits'] .= $this->msg( 'api-credits' )->useDatabase( false )->parseAsBlock();
1651                         if ( !isset( $tocData['main/credits'] ) ) {
1652                                 $tocnumber[$level]++;
1653                                 $tocData['main/credits'] = [
1654                                         'toclevel' => count( $tocnumber ),
1655                                         'level' => $level,
1656                                         'anchor' => 'main/credits',
1657                                         'line' => $header,
1658                                         'number' => join( '.', $tocnumber ),
1659                                         'index' => false,
1660                                 ];
1661                         }
1662                 }
1663         }
1664
1665         private $mCanApiHighLimits = null;
1666
1667         /**
1668          * Check whether the current user is allowed to use high limits
1669          * @return bool
1670          */
1671         public function canApiHighLimits() {
1672                 if ( !isset( $this->mCanApiHighLimits ) ) {
1673                         $this->mCanApiHighLimits = $this->getUser()->isAllowed( 'apihighlimits' );
1674                 }
1675
1676                 return $this->mCanApiHighLimits;
1677         }
1678
1679         /**
1680          * Overrides to return this instance's module manager.
1681          * @return ApiModuleManager
1682          */
1683         public function getModuleManager() {
1684                 return $this->mModuleMgr;
1685         }
1686
1687         /**
1688          * Fetches the user agent used for this request
1689          *
1690          * The value will be the combination of the 'Api-User-Agent' header (if
1691          * any) and the standard User-Agent header (if any).
1692          *
1693          * @return string
1694          */
1695         public function getUserAgent() {
1696                 return trim(
1697                         $this->getRequest()->getHeader( 'Api-user-agent' ) . ' ' .
1698                         $this->getRequest()->getHeader( 'User-agent' )
1699                 );
1700         }
1701
1702         /************************************************************************//**
1703          * @name   Deprecated
1704          * @{
1705          */
1706
1707         /**
1708          * Sets whether the pretty-printer should format *bold* and $italics$
1709          *
1710          * @deprecated since 1.25
1711          * @param bool $help
1712          */
1713         public function setHelp( $help = true ) {
1714                 wfDeprecated( __METHOD__, '1.25' );
1715                 $this->mPrinter->setHelp( $help );
1716         }
1717
1718         /**
1719          * Override the parent to generate help messages for all available modules.
1720          *
1721          * @deprecated since 1.25
1722          * @return string
1723          */
1724         public function makeHelpMsg() {
1725                 wfDeprecated( __METHOD__, '1.25' );
1726
1727                 $this->setHelp();
1728                 $cacheHelpTimeout = $this->getConfig()->get( 'APICacheHelpTimeout' );
1729
1730                 return ObjectCache::getMainWANInstance()->getWithSetCallback(
1731                         wfMemcKey(
1732                                 'apihelp',
1733                                 $this->getModuleName(),
1734                                 str_replace( ' ', '_', SpecialVersion::getVersion( 'nodb' ) )
1735                         ),
1736                         $cacheHelpTimeout > 0 ? $cacheHelpTimeout : WANObjectCache::TTL_UNCACHEABLE,
1737                         [ $this, 'reallyMakeHelpMsg' ]
1738                 );
1739         }
1740
1741         /**
1742          * @deprecated since 1.25
1743          * @return mixed|string
1744          */
1745         public function reallyMakeHelpMsg() {
1746                 wfDeprecated( __METHOD__, '1.25' );
1747                 $this->setHelp();
1748
1749                 // Use parent to make default message for the main module
1750                 $msg = parent::makeHelpMsg();
1751
1752                 $astriks = str_repeat( '*** ', 14 );
1753                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
1754
1755                 foreach ( $this->mModuleMgr->getNames( 'action' ) as $name ) {
1756                         $module = $this->mModuleMgr->getModule( $name );
1757                         $msg .= self::makeHelpMsgHeader( $module, 'action' );
1758
1759                         $msg2 = $module->makeHelpMsg();
1760                         if ( $msg2 !== false ) {
1761                                 $msg .= $msg2;
1762                         }
1763                         $msg .= "\n";
1764                 }
1765
1766                 $msg .= "\n$astriks Permissions $astriks\n\n";
1767                 foreach ( self::$mRights as $right => $rightMsg ) {
1768                         $rightsMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )
1769                                 ->useDatabase( false )
1770                                 ->inLanguage( 'en' )
1771                                 ->text();
1772                         $groups = User::getGroupsWithPermission( $right );
1773                         $msg .= "* " . $right . " *\n  $rightsMsg" .
1774                                 "\nGranted to:\n  " . str_replace( '*', 'all', implode( ', ', $groups ) ) . "\n\n";
1775                 }
1776
1777                 $msg .= "\n$astriks Formats  $astriks\n\n";
1778                 foreach ( $this->mModuleMgr->getNames( 'format' ) as $name ) {
1779                         $module = $this->mModuleMgr->getModule( $name );
1780                         $msg .= self::makeHelpMsgHeader( $module, 'format' );
1781                         $msg2 = $module->makeHelpMsg();
1782                         if ( $msg2 !== false ) {
1783                                 $msg .= $msg2;
1784                         }
1785                         $msg .= "\n";
1786                 }
1787
1788                 $credits = $this->msg( 'api-credits' )->useDatabase( 'false' )->inLanguage( 'en' )->text();
1789                 $credits = str_replace( "\n", "\n   ", $credits );
1790                 $msg .= "\n*** Credits: ***\n   $credits\n";
1791
1792                 return $msg;
1793         }
1794
1795         /**
1796          * @deprecated since 1.25
1797          * @param ApiBase $module
1798          * @param string $paramName What type of request is this? e.g. action,
1799          *    query, list, prop, meta, format
1800          * @return string
1801          */
1802         public static function makeHelpMsgHeader( $module, $paramName ) {
1803                 wfDeprecated( __METHOD__, '1.25' );
1804                 $modulePrefix = $module->getModulePrefix();
1805                 if ( strval( $modulePrefix ) !== '' ) {
1806                         $modulePrefix = "($modulePrefix) ";
1807                 }
1808
1809                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
1810         }
1811
1812         /**
1813          * Check whether the user wants us to show version information in the API help
1814          * @return bool
1815          * @deprecated since 1.21, always returns false
1816          */
1817         public function getShowVersions() {
1818                 wfDeprecated( __METHOD__, '1.21' );
1819
1820                 return false;
1821         }
1822
1823         /**
1824          * Add or overwrite a module in this ApiMain instance. Intended for use by extending
1825          * classes who wish to add their own modules to their lexicon or override the
1826          * behavior of inherent ones.
1827          *
1828          * @deprecated since 1.21, Use getModuleManager()->addModule() instead.
1829          * @param string $name The identifier for this module.
1830          * @param ApiBase $class The class where this module is implemented.
1831          */
1832         protected function addModule( $name, $class ) {
1833                 $this->getModuleManager()->addModule( $name, 'action', $class );
1834         }
1835
1836         /**
1837          * Add or overwrite an output format for this ApiMain. Intended for use by extending
1838          * classes who wish to add to or modify current formatters.
1839          *
1840          * @deprecated since 1.21, Use getModuleManager()->addModule() instead.
1841          * @param string $name The identifier for this format.
1842          * @param ApiFormatBase $class The class implementing this format.
1843          */
1844         protected function addFormat( $name, $class ) {
1845                 $this->getModuleManager()->addModule( $name, 'format', $class );
1846         }
1847
1848         /**
1849          * Returns the list of supported formats in form ( 'format' => 'ClassName' )
1850          *
1851          * @since 1.18
1852          * @deprecated since 1.21, Use getModuleManager()'s methods instead.
1853          * @return array
1854          */
1855         public function getFormats() {
1856                 return $this->getModuleManager()->getNamesWithClasses( 'format' );
1857         }
1858
1859         /**@}*/
1860
1861 }
1862
1863 /**
1864  * This exception will be thrown when dieUsage is called to stop module execution.
1865  *
1866  * @ingroup API
1867  */
1868 class UsageException extends MWException {
1869
1870         private $mCodestr;
1871
1872         /**
1873          * @var null|array
1874          */
1875         private $mExtraData;
1876
1877         /**
1878          * @param string $message
1879          * @param string $codestr
1880          * @param int $code
1881          * @param array|null $extradata
1882          */
1883         public function __construct( $message, $codestr, $code = 0, $extradata = null ) {
1884                 parent::__construct( $message, $code );
1885                 $this->mCodestr = $codestr;
1886                 $this->mExtraData = $extradata;
1887         }
1888
1889         /**
1890          * @return string
1891          */
1892         public function getCodeString() {
1893                 return $this->mCodestr;
1894         }
1895
1896         /**
1897          * @return array
1898          */
1899         public function getMessageArray() {
1900                 $result = [
1901                         'code' => $this->mCodestr,
1902                         'info' => $this->getMessage()
1903                 ];
1904                 if ( is_array( $this->mExtraData ) ) {
1905                         $result = array_merge( $result, $this->mExtraData );
1906                 }
1907
1908                 return $result;
1909         }
1910
1911         /**
1912          * @return string
1913          */
1914         public function __toString() {
1915                 return "{$this->getCodeString()}: {$this->getMessage()}";
1916         }
1917 }
1918
1919 /**
1920  * For really cool vim folding this needs to be at the end:
1921  * vim: foldmarker=@{,@} foldmethod=marker
1922  */