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