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                 'wddx' => 'ApiFormatWddx',
 104                 'wddxfm' => 'ApiFormatWddx',
 105                 'xml' => 'ApiFormatXml',
 106                 'xmlfm' => 'ApiFormatXml',
 107                 'yaml' => 'ApiFormatYaml',
 108                 'yamlfm' => 'ApiFormatYaml',
 109                 'rawfm' => 'ApiFormatJson',
 110                 'txt' => 'ApiFormatTxt',
 111                 'txtfm' => 'ApiFormatTxt',
 112                 'dbg' => 'ApiFormatDbg',
 113                 'dbgfm' => 'ApiFormatDbg',
 114                 'dump' => 'ApiFormatDump',
 115                 'dumpfm' => 'ApiFormatDump',
 116                 'none' => 'ApiFormatNone',
 117         );
 118
 119         // @codingStandardsIgnoreStart String contenation on "msg" not allowed to break long line
 120         /**
 121          * List of user roles that are specifically relevant to the API.
 122          * array( 'right' => array ( 'msg'    => 'Some message with a $1',
 123          *                           'params' => array ( $someVarToSubst ) ),
 124          *                          );
 125          */
 126         private static $mRights = array(
 127                 'writeapi' => array(
 128                         'msg' => 'right-writeapi',
 129                         'params' => array()
 130                 ),
 131                 'apihighlimits' => array(
 132                         'msg' => 'api-help-right-apihighlimits',
 133                         'params' => array( ApiBase::LIMIT_SML2, ApiBase::LIMIT_BIG2 )
 134                 )
 135         );
 136         // @codingStandardsIgnoreEnd
 137
 138         /**
 139          * @var ApiFormatBase
 140          */
 141         private $mPrinter;
 142
 143         private $mModuleMgr, $mResult, $mErrorFormatter, $mContinuationManager;
 144         private $mAction;
 145         private $mEnableWrite;
 146         private $mInternalMode, $mSquidMaxage, $mModule;
 147
 148         private $mCacheMode = 'private';
 149         private $mCacheControl = array();
 150         private $mParamsUsed = array();
 151
 152         /**
 153          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 154          *
 155          * @param IContextSource|WebRequest $context If this is an instance of
 156          *    FauxRequest, errors are thrown and no printing occurs
 157          * @param bool $enableWrite Should be set to true if the api may modify data
 158          */
 159         public function __construct( $context = null, $enableWrite = false ) {
 160                 if ( $context === null ) {
 161                         $context = RequestContext::getMain();
 162                 } elseif ( $context instanceof WebRequest ) {
 163                         // BC for pre-1.19
 164                         $request = $context;
 165                         $context = RequestContext::getMain();
 166                 }
 167                 // We set a derivative context so we can change stuff later
 168                 $this->setContext( new DerivativeContext( $context ) );
 169
 170                 if ( isset( $request ) ) {
 171                         $this->getContext()->setRequest( $request );
 172                 }
 173
 174                 $this->mInternalMode = ( $this->getRequest() instanceof FauxRequest );
 175
 176                 // Special handling for the main module: $parent === $this
 177                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 178
 179                 if ( !$this->mInternalMode ) {
 180                         // Impose module restrictions.
 181                         // If the current user cannot read,
 182                         // Remove all modules other than login
 183                         global $wgUser;
 184
 185                         if ( $this->lacksSameOriginSecurity() ) {
 186                                 // If we're in a mode that breaks the same-origin policy, strip
 187                                 // user credentials for security.
 188                                 wfDebug( "API: stripping user credentials when the same-origin policy is not applied\n" );
 189                                 $wgUser = new User();
 190                                 $this->getContext()->setUser( $wgUser );
 191                         }
 192                 }
 193
 194                 $uselang = $this->getParameter( 'uselang' );
 195                 if ( $uselang === 'user' ) {
 196                         // Assume the parent context is going to return the user language
 197                         // for uselang=user (see T85635).
 198                 } else {
 199                         if ( $uselang === 'content' ) {
 200                                 global $wgContLang;
 201                                 $uselang = $wgContLang->getCode();
 202                         }
 203                         $code = RequestContext::sanitizeLangCode( $uselang );
 204                         $this->getContext()->setLanguage( $code );
 205                         if ( !$this->mInternalMode ) {
 206                                 global $wgLang;
 207                                 $wgLang = $this->getContext()->getLanguage();
 208                                 RequestContext::getMain()->setLanguage( $wgLang );
 209                         }
 210                 }
 211
 212                 $config = $this->getConfig();
 213                 $this->mModuleMgr = new ApiModuleManager( $this );
 214                 $this->mModuleMgr->addModules( self::$Modules, 'action' );
 215                 $this->mModuleMgr->addModules( $config->get( 'APIModules' ), 'action' );
 216                 $this->mModuleMgr->addModules( self::$Formats, 'format' );
 217                 $this->mModuleMgr->addModules( $config->get( 'APIFormatModules' ), 'format' );
 218
 219                 Hooks::run( 'ApiMain::moduleManager', array( $this->mModuleMgr ) );
 220
 221                 $this->mResult = new ApiResult( $this->getConfig()->get( 'APIMaxResultSize' ) );
 222                 $this->mErrorFormatter = new ApiErrorFormatter_BackCompat( $this->mResult );
 223                 $this->mResult->setErrorFormatter( $this->mErrorFormatter );
 224                 $this->mResult->setMainForContinuation( $this );
 225                 $this->mContinuationManager = null;
 226                 $this->mEnableWrite = $enableWrite;
 227
 228                 $this->mSquidMaxage = -1; // flag for executeActionWithErrorHandling()
 229                 $this->mCommit = false;
 230         }
 231
 232         /**
 233          * Return true if the API was started by other PHP code using FauxRequest
 234          * @return bool
 235          */
 236         public function isInternalMode() {
 237                 return $this->mInternalMode;
 238         }
 239
 240         /**
 241          * Get the ApiResult object associated with current request
 242          *
 243          * @return ApiResult
 244          */
 245         public function getResult() {
 246                 return $this->mResult;
 247         }
 248
 249         /**
 250          * Get the ApiErrorFormatter object associated with current request
 251          * @return ApiErrorFormatter
 252          */
 253         public function getErrorFormatter() {
 254                 return $this->mErrorFormatter;
 255         }
 256
 257         /**
 258          * Get the continuation manager
 259          * @return ApiContinuationManager|null
 260          */
 261         public function getContinuationManager() {
 262                 return $this->mContinuationManager;
 263         }
 264
 265         /**
 266          * Set the continuation manager
 267          * @param ApiContinuationManager|null
 268          */
 269         public function setContinuationManager( $manager ) {
 270                 if ( $manager !== null ) {
 271                         if ( !$manager instanceof ApiContinuationManager ) {
 272                                 throw new InvalidArgumentException( __METHOD__ . ': Was passed ' .
 273                                         is_object( $manager ) ? get_class( $manager ) : gettype( $manager )
 274                                 );
 275                         }
 276                         if ( $this->mContinuationManager !== null ) {
 277                                 throw new UnexpectedValueException(
 278                                         __METHOD__ . ': tried to set manager from ' . $manager->getSource() .
 279                                         ' when a manager is already set from ' . $this->mContinuationManager->getSource()
 280                                 );
 281                         }
 282                 }
 283                 $this->mContinuationManager = $manager;
 284         }
 285
 286         /**
 287          * Get the API module object. Only works after executeAction()
 288          *
 289          * @return ApiBase
 290          */
 291         public function getModule() {
 292                 return $this->mModule;
 293         }
 294
 295         /**
 296          * Get the result formatter object. Only works after setupExecuteAction()
 297          *
 298          * @return ApiFormatBase
 299          */
 300         public function getPrinter() {
 301                 return $this->mPrinter;
 302         }
 303
 304         /**
 305          * Set how long the response should be cached.
 306          *
 307          * @param int $maxage
 308          */
 309         public function setCacheMaxAge( $maxage ) {
 310                 $this->setCacheControl( array(
 311                         'max-age' => $maxage,
 312                         's-maxage' => $maxage
 313                 ) );
 314         }
 315
 316         /**
 317          * Set the type of caching headers which will be sent.
 318          *
 319          * @param string $mode One of:
 320          *    - 'public':     Cache this object in public caches, if the maxage or smaxage
 321          *         parameter is set, or if setCacheMaxAge() was called. If a maximum age is
 322          *         not provided by any of these means, the object will be private.
 323          *    - 'private':    Cache this object only in private client-side caches.
 324          *    - 'anon-public-user-private': Make this object cacheable for logged-out
 325          *         users, but private for logged-in users. IMPORTANT: If this is set, it must be
 326          *         set consistently for a given URL, it cannot be set differently depending on
 327          *         things like the contents of the database, or whether the user is logged in.
 328          *
 329          *  If the wiki does not allow anonymous users to read it, the mode set here
 330          *  will be ignored, and private caching headers will always be sent. In other words,
 331          *  the "public" mode is equivalent to saying that the data sent is as public as a page
 332          *  view.
 333          *
 334          *  For user-dependent data, the private mode should generally be used. The
 335          *  anon-public-user-private mode should only be used where there is a particularly
 336          *  good performance reason for caching the anonymous response, but where the
 337          *  response to logged-in users may differ, or may contain private data.
 338          *
 339          *  If this function is never called, then the default will be the private mode.
 340          */
 341         public function setCacheMode( $mode ) {
 342                 if ( !in_array( $mode, array( 'private', 'public', 'anon-public-user-private' ) ) ) {
 343                         wfDebug( __METHOD__ . ": unrecognised cache mode \"$mode\"\n" );
 344
 345                         // Ignore for forwards-compatibility
 346                         return;
 347                 }
 348
 349                 if ( !User::isEveryoneAllowed( 'read' ) ) {
 350                         // Private wiki, only private headers
 351                         if ( $mode !== 'private' ) {
 352                                 wfDebug( __METHOD__ . ": ignoring request for $mode cache mode, private wiki\n" );
 353
 354                                 return;
 355                         }
 356                 }
 357
 358                 if ( $mode === 'public' && $this->getParameter( 'uselang' ) === 'user' ) {
 359                         // User language is used for i18n, so we don't want to publicly
 360                         // cache. Anons are ok, because if they have non-default language
 361                         // then there's an appropriate Vary header set by whatever set
 362                         // their non-default language.
 363                         wfDebug( __METHOD__ . ": downgrading cache mode 'public' to " .
 364                                 "'anon-public-user-private' due to uselang=user\n" );
 365                         $mode = 'anon-public-user-private';
 366                 }
 367
 368                 wfDebug( __METHOD__ . ": setting cache mode $mode\n" );
 369                 $this->mCacheMode = $mode;
 370         }
 371
 372         /**
 373          * Set directives (key/value pairs) for the Cache-Control header.
 374          * Boolean values will be formatted as such, by including or omitting
 375          * without an equals sign.
 376          *
 377          * Cache control values set here will only be used if the cache mode is not
 378          * private, see setCacheMode().
 379          *
 380          * @param array $directives
 381          */
 382         public function setCacheControl( $directives ) {
 383                 $this->mCacheControl = $directives + $this->mCacheControl;
 384         }
 385
 386         /**
 387          * Create an instance of an output formatter by its name
 388          *
 389          * @param string $format
 390          *
 391          * @return ApiFormatBase
 392          */
 393         public function createPrinterByName( $format ) {
 394                 $printer = $this->mModuleMgr->getModule( $format, 'format' );
 395                 if ( $printer === null ) {
 396                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 397                 }
 398
 399                 return $printer;
 400         }
 401
 402         /**
 403          * Execute api request. Any errors will be handled if the API was called by the remote client.
 404          */
 405         public function execute() {
 406                 if ( $this->mInternalMode ) {
 407                         $this->executeAction();
 408                 } else {
 409                         $this->executeActionWithErrorHandling();
 410                 }
 411         }
 412
 413         /**
 414          * Execute an action, and in case of an error, erase whatever partial results
 415          * have been accumulated, and replace it with an error message and a help screen.
 416          */
 417         protected function executeActionWithErrorHandling() {
 418                 // Verify the CORS header before executing the action
 419                 if ( !$this->handleCORS() ) {
 420                         // handleCORS() has sent a 403, abort
 421                         return;
 422                 }
 423
 424                 // Exit here if the request method was OPTIONS
 425                 // (assume there will be a followup GET or POST)
 426                 if ( $this->getRequest()->getMethod() === 'OPTIONS' ) {
 427                         return;
 428                 }
 429
 430                 // In case an error occurs during data output,
 431                 // clear the output buffer and print just the error information
 432                 ob_start();
 433
 434                 $t = microtime( true );
 435                 try {
 436                         $this->executeAction();
 437                 } catch ( Exception $e ) {
 438                         $this->handleException( $e );
 439                 }
 440
 441                 // Log the request whether or not there was an error
 442                 $this->logRequest( microtime( true ) - $t );
 443
 444                 // Send cache headers after any code which might generate an error, to
 445                 // avoid sending public cache headers for errors.
 446                 $this->sendCacheHeaders();
 447
 448                 ob_end_flush();
 449         }
 450
 451         /**
 452          * Handle an exception as an API response
 453          *
 454          * @since 1.23
 455          * @param Exception $e
 456          */
 457         protected function handleException( Exception $e ) {
 458                 // Bug 63145: Rollback any open database transactions
 459                 if ( !( $e instanceof UsageException ) ) {
 460                         // UsageExceptions are intentional, so don't rollback if that's the case
 461                         try {
 462                                 MWExceptionHandler::rollbackMasterChangesAndLog( $e );
 463                         } catch ( DBError $e2 ) {
 464                                 // Rollback threw an exception too. Log it, but don't interrupt
 465                                 // our regularly scheduled exception handling.
 466                                 MWExceptionHandler::logException( $e2 );
 467                         }
 468                 }
 469
 470                 // Allow extra cleanup and logging
 471                 Hooks::run( 'ApiMain::onException', array( $this, $e ) );
 472
 473                 // Log it
 474                 if ( !( $e instanceof UsageException ) ) {
 475                         MWExceptionHandler::logException( $e );
 476                 }
 477
 478                 // Handle any kind of exception by outputting properly formatted error message.
 479                 // If this fails, an unhandled exception should be thrown so that global error
 480                 // handler will process and log it.
 481
 482                 $errCode = $this->substituteResultWithError( $e );
 483
 484                 // Error results should not be cached
 485                 $this->setCacheMode( 'private' );
 486
 487                 $response = $this->getRequest()->response();
 488                 $headerStr = 'MediaWiki-API-Error: ' . $errCode;
 489                 if ( $e->getCode() === 0 ) {
 490                         $response->header( $headerStr );
 491                 } else {
 492                         $response->header( $headerStr, true, $e->getCode() );
 493                 }
 494
 495                 // Reset and print just the error message
 496                 ob_clean();
 497
 498                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 499                 $this->createErrorPrinter();
 500
 501                 try {
 502                         $this->printResult( true );
 503                 } catch ( UsageException $ex ) {
 504                         // The error printer itself is failing. Try suppressing its request
 505                         // parameters and redo.
 506                         $this->setWarning(
 507                                 'Error printer failed (will retry without params): ' . $ex->getMessage()
 508                         );
 509                         $this->mPrinter = null;
 510                         $this->createErrorPrinter();
 511                         $this->mPrinter->forceDefaultParams();
 512                         $this->printResult( true );
 513                 }
 514         }
 515
 516         /**
 517          * Handle an exception from the ApiBeforeMain hook.
 518          *
 519          * This tries to print the exception as an API response, to be more
 520          * friendly to clients. If it fails, it will rethrow the exception.
 521          *
 522          * @since 1.23
 523          * @param Exception $e
 524          * @throws Exception
 525          */
 526         public static function handleApiBeforeMainException( Exception $e ) {
 527                 ob_start();
 528
 529                 try {
 530                         $main = new self( RequestContext::getMain(), false );
 531                         $main->handleException( $e );
 532                 } catch ( Exception $e2 ) {
 533                         // Nope, even that didn't work. Punt.
 534                         throw $e;
 535                 }
 536
 537                 // Log the request and reset cache headers
 538                 $main->logRequest( 0 );
 539                 $main->sendCacheHeaders();
 540
 541                 ob_end_flush();
 542         }
 543
 544         /**
 545          * Check the &origin= query parameter against the Origin: HTTP header and respond appropriately.
 546          *
 547          * If no origin parameter is present, nothing happens.
 548          * If an origin parameter is present but doesn't match the Origin header, a 403 status code
 549          * is set and false is returned.
 550          * If the parameter and the header do match, the header is checked against $wgCrossSiteAJAXdomains
 551          * and $wgCrossSiteAJAXdomainExceptions, and if the origin qualifies, the appropriate CORS
 552          * headers are set.
 553          * http://www.w3.org/TR/cors/#resource-requests
 554          * http://www.w3.org/TR/cors/#resource-preflight-requests
 555          *
 556          * @return bool False if the caller should abort (403 case), true otherwise (all other cases)
 557          */
 558         protected function handleCORS() {
 559                 $originParam = $this->getParameter( 'origin' ); // defaults to null
 560                 if ( $originParam === null ) {
 561                         // No origin parameter, nothing to do
 562                         return true;
 563                 }
 564
 565                 $request = $this->getRequest();
 566                 $response = $request->response();
 567
 568                 // Origin: header is a space-separated list of origins, check all of them
 569                 $originHeader = $request->getHeader( 'Origin' );
 570                 if ( $originHeader === false ) {
 571                         $origins = array();
 572                 } else {
 573                         $originHeader = trim( $originHeader );
 574                         $origins = preg_split( '/\s+/', $originHeader );
 575                 }
 576
 577                 if ( !in_array( $originParam, $origins ) ) {
 578                         // origin parameter set but incorrect
 579                         // Send a 403 response
 580                         $message = HttpStatus::getMessage( 403 );
 581                         $response->header( "HTTP/1.1 403 $message", true, 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                         $response->header( "Timing-Allow-Origin: $originHeader" ); # http://www.w3.org/TR/resource-timing/#timing-allow-origin
 620
 621                         if ( !$preflight ) {
 622                                 $response->header( 'Access-Control-Expose-Headers: MediaWiki-API-Error, Retry-After, X-Database-Lag' );
 623                         }
 624                 }
 625
 626                 $this->getOutput()->addVaryHeader( 'Origin' );
 627                 return true;
 628         }
 629
 630         /**
 631          * Attempt to match an Origin header against a set of rules and a set of exceptions
 632          * @param string $value Origin header
 633          * @param array $rules Set of wildcard rules
 634          * @param array $exceptions Set of wildcard rules
 635          * @return bool True if $value matches a rule in $rules and doesn't match
 636          *    any rules in $exceptions, false otherwise
 637          */
 638         protected static function matchOrigin( $value, $rules, $exceptions ) {
 639                 foreach ( $rules as $rule ) {
 640                         if ( preg_match( self::wildcardToRegex( $rule ), $value ) ) {
 641                                 // Rule matches, check exceptions
 642                                 foreach ( $exceptions as $exc ) {
 643                                         if ( preg_match( self::wildcardToRegex( $exc ), $value ) ) {
 644                                                 return false;
 645                                         }
 646                                 }
 647
 648                                 return true;
 649                         }
 650                 }
 651
 652                 return false;
 653         }
 654
 655         /**
 656          * Attempt to validate the value of Access-Control-Request-Headers against a list
 657          * of headers that we allow the follow up request to send.
 658          *
 659          * @param string $requestedHeaders Comma seperated list of HTTP headers
 660          * @return bool True if all requested headers are in the list of allowed headers
 661          */
 662         protected static function matchRequestedHeaders( $requestedHeaders ) {
 663                 if ( trim( $requestedHeaders ) === '' ) {
 664                         return true;
 665                 }
 666                 $requestedHeaders = explode( ',', $requestedHeaders );
 667                 $allowedAuthorHeaders = array_flip( array(
 668                         /* simple headers (see spec) */
 669                         'accept',
 670                         'accept-language',
 671                         'content-language',
 672                         'content-type',
 673                         /* non-authorable headers in XHR, which are however requested by some UAs */
 674                         'accept-encoding',
 675                         'dnt',
 676                         'origin',
 677                         /* MediaWiki whitelist */
 678                         'api-user-agent',
 679                 ) );
 680                 foreach ( $requestedHeaders as $rHeader ) {
 681                         $rHeader = strtolower( trim( $rHeader ) );
 682                         if ( !isset( $allowedAuthorHeaders[$rHeader] ) ) {
 683                                 wfDebugLog( 'api', 'CORS preflight failed on requested header: ' . $rHeader );
 684                                 return false;
 685                         }
 686                 }
 687                 return true;
 688         }
 689
 690         /**
 691          * Helper function to convert wildcard string into a regex
 692          * '*' => '.*?'
 693          * '?' => '.'
 694          *
 695          * @param string $wildcard String with wildcards
 696          * @return string Regular expression
 697          */
 698         protected static function wildcardToRegex( $wildcard ) {
 699                 $wildcard = preg_quote( $wildcard, '/' );
 700                 $wildcard = str_replace(
 701                         array( '\*', '\?' ),
 702                         array( '.*?', '.' ),
 703                         $wildcard
 704                 );
 705
 706                 return "/^https?:\/\/$wildcard$/";
 707         }
 708
 709         protected function sendCacheHeaders() {
 710                 $response = $this->getRequest()->response();
 711                 $out = $this->getOutput();
 712
 713                 $config = $this->getConfig();
 714
 715                 if ( $config->get( 'VaryOnXFP' ) ) {
 716                         $out->addVaryHeader( 'X-Forwarded-Proto' );
 717                 }
 718
 719                 // The logic should be:
 720                 // $this->mCacheControl['max-age'] is set?
 721                 //    Use it, the module knows better than our guess.
 722                 // !$this->mModule || $this->mModule->isWriteMode(), and mCacheMode is private?
 723                 //    Use 0 because we can guess caching is probably the wrong thing to do.
 724                 // Use $this->getParameter( 'maxage' ), which already defaults to 0.
 725                 $maxage = 0;
 726                 if ( isset( $this->mCacheControl['max-age'] ) ) {
 727                         $maxage = $this->mCacheControl['max-age'];
 728                 } elseif ( ( $this->mModule && !$this->mModule->isWriteMode() ) ||
 729                         $this->mCacheMode !== 'private'
 730                 ) {
 731                         $maxage = $this->getParameter( 'maxage' );
 732                 }
 733                 $privateCache = 'private, must-revalidate, max-age=' . $maxage;
 734
 735                 if ( $this->mCacheMode == 'private' ) {
 736                         $response->header( "Cache-Control: $privateCache" );
 737                         return;
 738                 }
 739
 740                 $useXVO = $config->get( 'UseXVO' );
 741                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 742                         $out->addVaryHeader( 'Cookie' );
 743                         $response->header( $out->getVaryHeader() );
 744                         if ( $useXVO ) {
 745                                 $response->header( $out->getXVO() );
 746                                 if ( $out->haveCacheVaryCookies() ) {
 747                                         // Logged in, mark this request private
 748                                         $response->header( "Cache-Control: $privateCache" );
 749                                         return;
 750                                 }
 751                                 // Logged out, send normal public headers below
 752                         } elseif ( session_id() != '' ) {
 753                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 754                                 // Mark request private
 755                                 $response->header( "Cache-Control: $privateCache" );
 756
 757                                 return;
 758                         } // else no XVO and anonymous, send public headers below
 759                 }
 760
 761                 // Send public headers
 762                 $response->header( $out->getVaryHeader() );
 763                 if ( $useXVO ) {
 764                         $response->header( $out->getXVO() );
 765                 }
 766
 767                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 768                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 769                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 770                 }
 771                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 772                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 773                 }
 774
 775                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 776                         // Public cache not requested
 777                         // Sending a Vary header in this case is harmless, and protects us
 778                         // against conditional calls of setCacheMaxAge().
 779                         $response->header( "Cache-Control: $privateCache" );
 780
 781                         return;
 782                 }
 783
 784                 $this->mCacheControl['public'] = true;
 785
 786                 // Send an Expires header
 787                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 788                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 789                 $response->header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 790
 791                 // Construct the Cache-Control header
 792                 $ccHeader = '';
 793                 $separator = '';
 794                 foreach ( $this->mCacheControl as $name => $value ) {
 795                         if ( is_bool( $value ) ) {
 796                                 if ( $value ) {
 797                                         $ccHeader .= $separator . $name;
 798                                         $separator = ', ';
 799                                 }
 800                         } else {
 801                                 $ccHeader .= $separator . "$name=$value";
 802                                 $separator = ', ';
 803                         }
 804                 }
 805
 806                 $response->header( "Cache-Control: $ccHeader" );
 807         }
 808
 809         /**
 810          * Create the printer for error output
 811          */
 812         private function createErrorPrinter() {
 813                 if ( !isset( $this->mPrinter ) ) {
 814                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 815                         if ( !$this->mModuleMgr->isDefined( $value, 'format' ) ) {
 816                                 $value = self::API_DEFAULT_FORMAT;
 817                         }
 818                         $this->mPrinter = $this->createPrinterByName( $value );
 819                 }
 820
 821                 // Printer may not be able to handle errors. This is particularly
 822                 // likely if the module returns something for getCustomPrinter().
 823                 if ( !$this->mPrinter->canPrintErrors() ) {
 824                         $this->mPrinter = $this->createPrinterByName( self::API_DEFAULT_FORMAT );
 825                 }
 826         }
 827
 828         /**
 829          * Replace the result data with the information about an exception.
 830          * Returns the error code
 831          * @param Exception $e
 832          * @return string
 833          */
 834         protected function substituteResultWithError( $e ) {
 835                 $result = $this->getResult();
 836                 $config = $this->getConfig();
 837
 838                 if ( $e instanceof UsageException ) {
 839                         // User entered incorrect parameters - generate error response
 840                         $errMessage = $e->getMessageArray();
 841                         $link = wfExpandUrl( wfScript( 'api' ) );
 842                         ApiResult::setContentValue( $errMessage, 'docref', "See $link for API usage" );
 843                 } else {
 844                         // Something is seriously wrong
 845                         if ( ( $e instanceof DBQueryError ) && !$config->get( 'ShowSQLErrors' ) ) {
 846                                 $info = 'Database query error';
 847                         } else {
 848                                 $info = "Exception Caught: {$e->getMessage()}";
 849                         }
 850
 851                         $errMessage = array(
 852                                 'code' => 'internal_api_error_' . get_class( $e ),
 853                                 'info' => '[' . MWExceptionHandler::getLogId( $e ) . '] ' . $info,
 854                         );
 855                         if ( $config->get( 'ShowExceptionDetails' ) ) {
 856                                 ApiResult::setContentValue(
 857                                         $errMessage,
 858                                         'trace',
 859                                         MWExceptionHandler::getRedactedTraceAsString( $e )
 860                                 );
 861                         }
 862                 }
 863
 864                 // Remember all the warnings to re-add them later
 865                 $warnings = $result->getResultData( array( 'warnings' ) );
 866
 867                 $result->reset();
 868                 // Re-add the id
 869                 $requestid = $this->getParameter( 'requestid' );
 870                 if ( !is_null( $requestid ) ) {
 871                         $result->addValue( null, 'requestid', $requestid, ApiResult::NO_SIZE_CHECK );
 872                 }
 873                 if ( $config->get( 'ShowHostnames' ) ) {
 874                         // servedby is especially useful when debugging errors
 875                         $result->addValue( null, 'servedby', wfHostName(), ApiResult::NO_SIZE_CHECK );
 876                 }
 877                 if ( $warnings !== null ) {
 878                         $result->addValue( null, 'warnings', $warnings, ApiResult::NO_SIZE_CHECK );
 879                 }
 880
 881                 $result->addValue( null, 'error', $errMessage, ApiResult::NO_SIZE_CHECK );
 882
 883                 return $errMessage['code'];
 884         }
 885
 886         /**
 887          * Set up for the execution.
 888          * @return array
 889          */
 890         protected function setupExecuteAction() {
 891                 // First add the id to the top element
 892                 $result = $this->getResult();
 893                 $requestid = $this->getParameter( 'requestid' );
 894                 if ( !is_null( $requestid ) ) {
 895                         $result->addValue( null, 'requestid', $requestid );
 896                 }
 897
 898                 if ( $this->getConfig()->get( 'ShowHostnames' ) ) {
 899                         $servedby = $this->getParameter( 'servedby' );
 900                         if ( $servedby ) {
 901                                 $result->addValue( null, 'servedby', wfHostName() );
 902                         }
 903                 }
 904
 905                 if ( $this->getParameter( 'curtimestamp' ) ) {
 906                         $result->addValue( null, 'curtimestamp', wfTimestamp( TS_ISO_8601, time() ),
 907                                 ApiResult::NO_SIZE_CHECK );
 908                 }
 909
 910                 $params = $this->extractRequestParams();
 911
 912                 $this->mAction = $params['action'];
 913
 914                 if ( !is_string( $this->mAction ) ) {
 915                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 916                 }
 917
 918                 return $params;
 919         }
 920
 921         /**
 922          * Set up the module for response
 923          * @return ApiBase The module that will handle this action
 924          * @throws MWException
 925          * @throws UsageException
 926          */
 927         protected function setupModule() {
 928                 // Instantiate the module requested by the user
 929                 $module = $this->mModuleMgr->getModule( $this->mAction, 'action' );
 930                 if ( $module === null ) {
 931                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 932                 }
 933                 $moduleParams = $module->extractRequestParams();
 934
 935                 // Check token, if necessary
 936                 if ( $module->needsToken() === true ) {
 937                         throw new MWException(
 938                                 "Module '{$module->getModuleName()}' must be updated for the new token handling. " .
 939                                 "See documentation for ApiBase::needsToken for details."
 940                         );
 941                 }
 942                 if ( $module->needsToken() ) {
 943                         if ( !$module->mustBePosted() ) {
 944                                 throw new MWException(
 945                                         "Module '{$module->getModuleName()}' must require POST to use tokens."
 946                                 );
 947                         }
 948
 949                         if ( !isset( $moduleParams['token'] ) ) {
 950                                 $this->dieUsageMsg( array( 'missingparam', 'token' ) );
 951                         }
 952
 953                         if ( !$this->getConfig()->get( 'DebugAPI' ) &&
 954                                 array_key_exists(
 955                                         $module->encodeParamName( 'token' ),
 956                                         $this->getRequest()->getQueryValues()
 957                                 )
 958                         ) {
 959                                 $this->dieUsage(
 960                                         "The '{$module->encodeParamName( 'token' )}' parameter was found in the query string, but must be in the POST body",
 961                                         'mustposttoken'
 962                                 );
 963                         }
 964
 965                         if ( !$module->validateToken( $moduleParams['token'], $moduleParams ) ) {
 966                                 $this->dieUsageMsg( 'sessionfailure' );
 967                         }
 968                 }
 969
 970                 return $module;
 971         }
 972
 973         /**
 974          * Check the max lag if necessary
 975          * @param ApiBase $module Api module being used
 976          * @param array $params Array an array containing the request parameters.
 977          * @return bool True on success, false should exit immediately
 978          */
 979         protected function checkMaxLag( $module, $params ) {
 980                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
 981                         // Check for maxlag
 982                         $maxLag = $params['maxlag'];
 983                         list( $host, $lag ) = wfGetLB()->getMaxLag();
 984                         if ( $lag > $maxLag ) {
 985                                 $response = $this->getRequest()->response();
 986
 987                                 $response->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
 988                                 $response->header( 'X-Database-Lag: ' . intval( $lag ) );
 989
 990                                 if ( $this->getConfig()->get( 'ShowHostnames' ) ) {
 991                                         $this->dieUsage( "Waiting for $host: $lag seconds lagged", 'maxlag' );
 992                                 }
 993
 994                                 $this->dieUsage( "Waiting for a database server: $lag seconds lagged", 'maxlag' );
 995                         }
 996                 }
 997
 998                 return true;
 999         }
1000
1001         /**
1002          * Check for sufficient permissions to execute
1003          * @param ApiBase $module An Api module
1004          */
1005         protected function checkExecutePermissions( $module ) {
1006                 $user = $this->getUser();
1007                 if ( $module->isReadMode() && !User::isEveryoneAllowed( 'read' ) &&
1008                         !$user->isAllowed( 'read' )
1009                 ) {
1010                         $this->dieUsageMsg( 'readrequired' );
1011                 }
1012                 if ( $module->isWriteMode() ) {
1013                         if ( !$this->mEnableWrite ) {
1014                                 $this->dieUsageMsg( 'writedisabled' );
1015                         }
1016                         if ( !$user->isAllowed( 'writeapi' ) ) {
1017                                 $this->dieUsageMsg( 'writerequired' );
1018                         }
1019                         if ( wfReadOnly() ) {
1020                                 $this->dieReadOnly();
1021                         }
1022                 }
1023
1024                 // Allow extensions to stop execution for arbitrary reasons.
1025                 $message = false;
1026                 if ( !Hooks::run( 'ApiCheckCanExecute', array( $module, $user, &$message ) ) ) {
1027                         $this->dieUsageMsg( $message );
1028                 }
1029         }
1030
1031         /**
1032          * Check asserts of the user's rights
1033          * @param array $params
1034          */
1035         protected function checkAsserts( $params ) {
1036                 if ( isset( $params['assert'] ) ) {
1037                         $user = $this->getUser();
1038                         switch ( $params['assert'] ) {
1039                                 case 'user':
1040                                         if ( $user->isAnon() ) {
1041                                                 $this->dieUsage( 'Assertion that the user is logged in failed', 'assertuserfailed' );
1042                                         }
1043                                         break;
1044                                 case 'bot':
1045                                         if ( !$user->isAllowed( 'bot' ) ) {
1046                                                 $this->dieUsage( 'Assertion that the user has the bot right failed', 'assertbotfailed' );
1047                                         }
1048                                         break;
1049                         }
1050                 }
1051         }
1052
1053         /**
1054          * Check POST for external response and setup result printer
1055          * @param ApiBase $module An Api module
1056          * @param array $params An array with the request parameters
1057          */
1058         protected function setupExternalResponse( $module, $params ) {
1059                 if ( !$this->getRequest()->wasPosted() && $module->mustBePosted() ) {
1060                         // Module requires POST. GET request might still be allowed
1061                         // if $wgDebugApi is true, otherwise fail.
1062                         $this->dieUsageMsgOrDebug( array( 'mustbeposted', $this->mAction ) );
1063                 }
1064
1065                 // See if custom printer is used
1066                 $this->mPrinter = $module->getCustomPrinter();
1067                 if ( is_null( $this->mPrinter ) ) {
1068                         // Create an appropriate printer
1069                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
1070                 }
1071
1072                 if ( $this->mPrinter->getNeedsRawData() ) {
1073                         $this->getResult()->setRawMode();
1074                 }
1075         }
1076
1077         /**
1078          * Execute the actual module, without any error handling
1079          */
1080         protected function executeAction() {
1081                 $params = $this->setupExecuteAction();
1082                 $module = $this->setupModule();
1083                 $this->mModule = $module;
1084
1085                 $this->checkExecutePermissions( $module );
1086
1087                 if ( !$this->checkMaxLag( $module, $params ) ) {
1088                         return;
1089                 }
1090
1091                 if ( !$this->mInternalMode ) {
1092                         $this->setupExternalResponse( $module, $params );
1093                 }
1094
1095                 $this->checkAsserts( $params );
1096
1097                 // Execute
1098                 $module->execute();
1099                 Hooks::run( 'APIAfterExecute', array( &$module ) );
1100
1101                 $this->reportUnusedParams();
1102
1103                 if ( !$this->mInternalMode ) {
1104                         //append Debug information
1105                         MWDebug::appendDebugInfoToApiResult( $this->getContext(), $this->getResult() );
1106
1107                         // Print result data
1108                         $this->printResult( false );
1109                 }
1110         }
1111
1112         /**
1113          * Log the preceding request
1114          * @param int $time Time in seconds
1115          */
1116         protected function logRequest( $time ) {
1117                 $request = $this->getRequest();
1118                 $milliseconds = $time === null ? '?' : round( $time * 1000 );
1119                 $s = 'API' .
1120                         ' ' . $request->getMethod() .
1121                         ' ' . wfUrlencode( str_replace( ' ', '_', $this->getUser()->getName() ) ) .
1122                         ' ' . $request->getIP() .
1123                         ' T=' . $milliseconds . 'ms';
1124                 foreach ( $this->getParamsUsed() as $name ) {
1125                         $value = $request->getVal( $name );
1126                         if ( $value === null ) {
1127                                 continue;
1128                         }
1129                         $s .= ' ' . $name . '=';
1130                         if ( strlen( $value ) > 256 ) {
1131                                 $encValue = $this->encodeRequestLogValue( substr( $value, 0, 256 ) );
1132                                 $s .= $encValue . '[...]';
1133                         } else {
1134                                 $s .= $this->encodeRequestLogValue( $value );
1135                         }
1136                 }
1137                 $s .= "\n";
1138                 wfDebugLog( 'api', $s, 'private' );
1139         }
1140
1141         /**
1142          * Encode a value in a format suitable for a space-separated log line.
1143          * @param string $s
1144          * @return string
1145          */
1146         protected function encodeRequestLogValue( $s ) {
1147                 static $table;
1148                 if ( !$table ) {
1149                         $chars = ';@$!*(),/:';
1150                         $numChars = strlen( $chars );
1151                         for ( $i = 0; $i < $numChars; $i++ ) {
1152                                 $table[rawurlencode( $chars[$i] )] = $chars[$i];
1153                         }
1154                 }
1155
1156                 return strtr( rawurlencode( $s ), $table );
1157         }
1158
1159         /**
1160          * Get the request parameters used in the course of the preceding execute() request
1161          * @return array
1162          */
1163         protected function getParamsUsed() {
1164                 return array_keys( $this->mParamsUsed );
1165         }
1166
1167         /**
1168          * Get a request value, and register the fact that it was used, for logging.
1169          * @param string $name
1170          * @param mixed $default
1171          * @return mixed
1172          */
1173         public function getVal( $name, $default = null ) {
1174                 $this->mParamsUsed[$name] = true;
1175
1176                 $ret = $this->getRequest()->getVal( $name );
1177                 if ( $ret === null ) {
1178                         if ( $this->getRequest()->getArray( $name ) !== null ) {
1179                                 // See bug 10262 for why we don't just join( '|', ... ) the
1180                                 // array.
1181                                 $this->setWarning(
1182                                         "Parameter '$name' uses unsupported PHP array syntax"
1183                                 );
1184                         }
1185                         $ret = $default;
1186                 }
1187                 return $ret;
1188         }
1189
1190         /**
1191          * Get a boolean request value, and register the fact that the parameter
1192          * was used, for logging.
1193          * @param string $name
1194          * @return bool
1195          */
1196         public function getCheck( $name ) {
1197                 return $this->getVal( $name, null ) !== null;
1198         }
1199
1200         /**
1201          * Get a request upload, and register the fact that it was used, for logging.
1202          *
1203          * @since 1.21
1204          * @param string $name Parameter name
1205          * @return WebRequestUpload
1206          */
1207         public function getUpload( $name ) {
1208                 $this->mParamsUsed[$name] = true;
1209
1210                 return $this->getRequest()->getUpload( $name );
1211         }
1212
1213         /**
1214          * Report unused parameters, so the client gets a hint in case it gave us parameters we don't know,
1215          * for example in case of spelling mistakes or a missing 'g' prefix for generators.
1216          */
1217         protected function reportUnusedParams() {
1218                 $paramsUsed = $this->getParamsUsed();
1219                 $allParams = $this->getRequest()->getValueNames();
1220
1221                 if ( !$this->mInternalMode ) {
1222                         // Printer has not yet executed; don't warn that its parameters are unused
1223                         $printerParams = array_map(
1224                                 array( $this->mPrinter, 'encodeParamName' ),
1225                                 array_keys( $this->mPrinter->getFinalParams() ?: array() )
1226                         );
1227                         $unusedParams = array_diff( $allParams, $paramsUsed, $printerParams );
1228                 } else {
1229                         $unusedParams = array_diff( $allParams, $paramsUsed );
1230                 }
1231
1232                 if ( count( $unusedParams ) ) {
1233                         $s = count( $unusedParams ) > 1 ? 's' : '';
1234                         $this->setWarning( "Unrecognized parameter$s: '" . implode( $unusedParams, "', '" ) . "'" );
1235                 }
1236         }
1237
1238         /**
1239          * Print results using the current printer
1240          *
1241          * @param bool $isError
1242          */
1243         protected function printResult( $isError ) {
1244                 if ( $this->getConfig()->get( 'DebugAPI' ) !== false ) {
1245                         $this->setWarning( 'SECURITY WARNING: $wgDebugAPI is enabled' );
1246                 }
1247
1248                 $printer = $this->mPrinter;
1249                 $printer->initPrinter( false );
1250                 $printer->execute();
1251                 $printer->closePrinter();
1252         }
1253
1254         /**
1255          * @return bool
1256          */
1257         public function isReadMode() {
1258                 return false;
1259         }
1260
1261         /**
1262          * See ApiBase for description.
1263          *
1264          * @return array
1265          */
1266         public function getAllowedParams() {
1267                 return array(
1268                         'action' => array(
1269                                 ApiBase::PARAM_DFLT => 'help',
1270                                 ApiBase::PARAM_TYPE => 'submodule',
1271                         ),
1272                         'format' => array(
1273                                 ApiBase::PARAM_DFLT => ApiMain::API_DEFAULT_FORMAT,
1274                                 ApiBase::PARAM_TYPE => 'submodule',
1275                         ),
1276                         'maxlag' => array(
1277                                 ApiBase::PARAM_TYPE => 'integer'
1278                         ),
1279                         'smaxage' => array(
1280                                 ApiBase::PARAM_TYPE => 'integer',
1281                                 ApiBase::PARAM_DFLT => 0
1282                         ),
1283                         'maxage' => array(
1284                                 ApiBase::PARAM_TYPE => 'integer',
1285                                 ApiBase::PARAM_DFLT => 0
1286                         ),
1287                         'assert' => array(
1288                                 ApiBase::PARAM_TYPE => array( 'user', 'bot' )
1289                         ),
1290                         'requestid' => null,
1291                         'servedby' => false,
1292                         'curtimestamp' => false,
1293                         'origin' => null,
1294                         'uselang' => array(
1295                                 ApiBase::PARAM_DFLT => 'user',
1296                         ),
1297                 );
1298         }
1299
1300         /** @see ApiBase::getExamplesMessages() */
1301         protected function getExamplesMessages() {
1302                 return array(
1303                         'action=help'
1304                                 => 'apihelp-help-example-main',
1305                         'action=help&recursivesubmodules=1'
1306                                 => 'apihelp-help-example-recursive',
1307                 );
1308         }
1309
1310         public function modifyHelp( array &$help, array $options ) {
1311                 // Wish PHP had an "array_insert_before". Instead, we have to manually
1312                 // reindex the array to get 'permissions' in the right place.
1313                 $oldHelp = $help;
1314                 $help = array();
1315                 foreach ( $oldHelp as $k => $v ) {
1316                         if ( $k === 'submodules' ) {
1317                                 $help['permissions'] = '';
1318                         }
1319                         $help[$k] = $v;
1320                 }
1321                 $help['datatypes'] = '';
1322                 $help['credits'] = '';
1323
1324                 // Fill 'permissions'
1325                 $help['permissions'] .= Html::openElement( 'div',
1326                         array( 'class' => 'apihelp-block apihelp-permissions' ) );
1327                 $m = $this->msg( 'api-help-permissions' );
1328                 if ( !$m->isDisabled() ) {
1329                         $help['permissions'] .= Html::rawElement( 'div', array( 'class' => 'apihelp-block-head' ),
1330                                 $m->numParams( count( self::$mRights ) )->parse()
1331                         );
1332                 }
1333                 $help['permissions'] .= Html::openElement( 'dl' );
1334                 foreach ( self::$mRights as $right => $rightMsg ) {
1335                         $help['permissions'] .= Html::element( 'dt', null, $right );
1336
1337                         $rightMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )->parse();
1338                         $help['permissions'] .= Html::rawElement( 'dd', null, $rightMsg );
1339
1340                         $groups = array_map( function ( $group ) {
1341                                 return $group == '*' ? 'all' : $group;
1342                         }, User::getGroupsWithPermission( $right ) );
1343
1344                         $help['permissions'] .= Html::rawElement( 'dd', null,
1345                                 $this->msg( 'api-help-permissions-granted-to' )
1346                                         ->numParams( count( $groups ) )
1347                                         ->params( $this->getLanguage()->commaList( $groups ) )
1348                                         ->parse()
1349                         );
1350                 }
1351                 $help['permissions'] .= Html::closeElement( 'dl' );
1352                 $help['permissions'] .= Html::closeElement( 'div' );
1353
1354                 // Fill 'datatypes' and 'credits', if applicable
1355                 if ( empty( $options['nolead'] ) ) {
1356                         $help['datatypes'] .= Html::rawelement( 'h' . min( 6, $options['headerlevel'] + 1 ),
1357                                 array( 'id' => 'main/datatypes', 'class' => 'apihelp-header' ),
1358                                 Html::element( 'span', array( 'id' => Sanitizer::escapeId( 'main/datatypes' ) ) ) .
1359                                 $this->msg( 'api-help-datatypes-header' )->parse()
1360                         );
1361                         $help['datatypes'] .= $this->msg( 'api-help-datatypes' )->parseAsBlock();
1362
1363                         $help['credits'] .= Html::rawelement( 'h' . min( 6, $options['headerlevel'] + 1 ),
1364                                 array( 'id' => 'main/credits', 'class' => 'apihelp-header' ),
1365                                 Html::element( 'span', array( 'id' => Sanitizer::escapeId( 'main/credits' ) ) ) .
1366                                 $this->msg( 'api-credits-header' )->parse()
1367                         );
1368                         $help['credits'] .= $this->msg( 'api-credits' )->useDatabase( false )->parseAsBlock();
1369                 }
1370         }
1371
1372         private $mCanApiHighLimits = null;
1373
1374         /**
1375          * Check whether the current user is allowed to use high limits
1376          * @return bool
1377          */
1378         public function canApiHighLimits() {
1379                 if ( !isset( $this->mCanApiHighLimits ) ) {
1380                         $this->mCanApiHighLimits = $this->getUser()->isAllowed( 'apihighlimits' );
1381                 }
1382
1383                 return $this->mCanApiHighLimits;
1384         }
1385
1386         /**
1387          * Overrides to return this instance's module manager.
1388          * @return ApiModuleManager
1389          */
1390         public function getModuleManager() {
1391                 return $this->mModuleMgr;
1392         }
1393
1394         /**
1395          * Fetches the user agent used for this request
1396          *
1397          * The value will be the combination of the 'Api-User-Agent' header (if
1398          * any) and the standard User-Agent header (if any).
1399          *
1400          * @return string
1401          */
1402         public function getUserAgent() {
1403                 return trim(
1404                         $this->getRequest()->getHeader( 'Api-user-agent' ) . ' ' .
1405                         $this->getRequest()->getHeader( 'User-agent' )
1406                 );
1407         }
1408
1409         /************************************************************************//**
1410          * @name   Deprecated
1411          * @{
1412          */
1413
1414         /**
1415          * Sets whether the pretty-printer should format *bold* and $italics$
1416          *
1417          * @deprecated since 1.25
1418          * @param bool $help
1419          */
1420         public function setHelp( $help = true ) {
1421                 wfDeprecated( __METHOD__, '1.25' );
1422                 $this->mPrinter->setHelp( $help );
1423         }
1424
1425         /**
1426          * Override the parent to generate help messages for all available modules.
1427          *
1428          * @deprecated since 1.25
1429          * @return string
1430          */
1431         public function makeHelpMsg() {
1432                 wfDeprecated( __METHOD__, '1.25' );
1433                 global $wgMemc;
1434                 $this->setHelp();
1435                 // Get help text from cache if present
1436                 $key = wfMemcKey( 'apihelp', $this->getModuleName(),
1437                         str_replace( ' ', '_', SpecialVersion::getVersion( 'nodb' ) ) );
1438
1439                 $cacheHelpTimeout = $this->getConfig()->get( 'APICacheHelpTimeout' );
1440                 if ( $cacheHelpTimeout > 0 ) {
1441                         $cached = $wgMemc->get( $key );
1442                         if ( $cached ) {
1443                                 return $cached;
1444                         }
1445                 }
1446                 $retval = $this->reallyMakeHelpMsg();
1447                 if ( $cacheHelpTimeout > 0 ) {
1448                         $wgMemc->set( $key, $retval, $cacheHelpTimeout );
1449                 }
1450
1451                 return $retval;
1452         }
1453
1454         /**
1455          * @deprecated since 1.25
1456          * @return mixed|string
1457          */
1458         public function reallyMakeHelpMsg() {
1459                 wfDeprecated( __METHOD__, '1.25' );
1460                 $this->setHelp();
1461
1462                 // Use parent to make default message for the main module
1463                 $msg = parent::makeHelpMsg();
1464
1465                 $astriks = str_repeat( '*** ', 14 );
1466                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
1467
1468                 foreach ( $this->mModuleMgr->getNames( 'action' ) as $name ) {
1469                         $module = $this->mModuleMgr->getModule( $name );
1470                         $msg .= self::makeHelpMsgHeader( $module, 'action' );
1471
1472                         $msg2 = $module->makeHelpMsg();
1473                         if ( $msg2 !== false ) {
1474                                 $msg .= $msg2;
1475                         }
1476                         $msg .= "\n";
1477                 }
1478
1479                 $msg .= "\n$astriks Permissions $astriks\n\n";
1480                 foreach ( self::$mRights as $right => $rightMsg ) {
1481                         $rightsMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )
1482                                 ->useDatabase( false )
1483                                 ->inLanguage( 'en' )
1484                                 ->text();
1485                         $groups = User::getGroupsWithPermission( $right );
1486                         $msg .= "* " . $right . " *\n  $rightsMsg" .
1487                                 "\nGranted to:\n  " . str_replace( '*', 'all', implode( ', ', $groups ) ) . "\n\n";
1488                 }
1489
1490                 $msg .= "\n$astriks Formats  $astriks\n\n";
1491                 foreach ( $this->mModuleMgr->getNames( 'format' ) as $name ) {
1492                         $module = $this->mModuleMgr->getModule( $name );
1493                         $msg .= self::makeHelpMsgHeader( $module, 'format' );
1494                         $msg2 = $module->makeHelpMsg();
1495                         if ( $msg2 !== false ) {
1496                                 $msg .= $msg2;
1497                         }
1498                         $msg .= "\n";
1499                 }
1500
1501                 $credits = $this->msg( 'api-credits' )->useDatabase( 'false' )->inLanguage( 'en' )->text();
1502                 $credits = str_replace( "\n", "\n   ", $credits );
1503                 $msg .= "\n*** Credits: ***\n   $credits\n";
1504
1505                 return $msg;
1506         }
1507
1508         /**
1509          * @deprecated since 1.25
1510          * @param ApiBase $module
1511          * @param string $paramName What type of request is this? e.g. action,
1512          *    query, list, prop, meta, format
1513          * @return string
1514          */
1515         public static function makeHelpMsgHeader( $module, $paramName ) {
1516                 wfDeprecated( __METHOD__, '1.25' );
1517                 $modulePrefix = $module->getModulePrefix();
1518                 if ( strval( $modulePrefix ) !== '' ) {
1519                         $modulePrefix = "($modulePrefix) ";
1520                 }
1521
1522                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
1523         }
1524
1525         /**
1526          * Check whether the user wants us to show version information in the API help
1527          * @return bool
1528          * @deprecated since 1.21, always returns false
1529          */
1530         public function getShowVersions() {
1531                 wfDeprecated( __METHOD__, '1.21' );
1532
1533                 return false;
1534         }
1535
1536         /**
1537          * Add or overwrite a module in this ApiMain instance. Intended for use by extending
1538          * classes who wish to add their own modules to their lexicon or override the
1539          * behavior of inherent ones.
1540          *
1541          * @deprecated since 1.21, Use getModuleManager()->addModule() instead.
1542          * @param string $name The identifier for this module.
1543          * @param ApiBase $class The class where this module is implemented.
1544          */
1545         protected function addModule( $name, $class ) {
1546                 $this->getModuleManager()->addModule( $name, 'action', $class );
1547         }
1548
1549         /**
1550          * Add or overwrite an output format for this ApiMain. Intended for use by extending
1551          * classes who wish to add to or modify current formatters.
1552          *
1553          * @deprecated since 1.21, Use getModuleManager()->addModule() instead.
1554          * @param string $name The identifier for this format.
1555          * @param ApiFormatBase $class The class implementing this format.
1556          */
1557         protected function addFormat( $name, $class ) {
1558                 $this->getModuleManager()->addModule( $name, 'format', $class );
1559         }
1560
1561         /**
1562          * Get the array mapping module names to class names
1563          * @deprecated since 1.21, Use getModuleManager()'s methods instead.
1564          * @return array
1565          */
1566         function getModules() {
1567                 return $this->getModuleManager()->getNamesWithClasses( 'action' );
1568         }
1569
1570         /**
1571          * Returns the list of supported formats in form ( 'format' => 'ClassName' )
1572          *
1573          * @since 1.18
1574          * @deprecated since 1.21, Use getModuleManager()'s methods instead.
1575          * @return array
1576          */
1577         public function getFormats() {
1578                 return $this->getModuleManager()->getNamesWithClasses( 'format' );
1579         }
1580
1581         /**@}*/
1582
1583 }
1584
1585 /**
1586  * This exception will be thrown when dieUsage is called to stop module execution.
1587  *
1588  * @ingroup API
1589  */
1590 class UsageException extends MWException {
1591
1592         private $mCodestr;
1593
1594         /**
1595          * @var null|array
1596          */
1597         private $mExtraData;
1598
1599         /**
1600          * @param string $message
1601          * @param string $codestr
1602          * @param int $code
1603          * @param array|null $extradata
1604          */
1605         public function __construct( $message, $codestr, $code = 0, $extradata = null ) {
1606                 parent::__construct( $message, $code );
1607                 $this->mCodestr = $codestr;
1608                 $this->mExtraData = $extradata;
1609         }
1610
1611         /**
1612          * @return string
1613          */
1614         public function getCodeString() {
1615                 return $this->mCodestr;
1616         }
1617
1618         /**
1619          * @return array
1620          */
1621         public function getMessageArray() {
1622                 $result = array(
1623                         'code' => $this->mCodestr,
1624                         'info' => $this->getMessage()
1625                 );
1626                 if ( is_array( $this->mExtraData ) ) {
1627                         $result = array_merge( $result, $this->mExtraData );
1628                 }
1629
1630                 return $result;
1631         }
1632
1633         /**
1634          * @return string
1635          */
1636         public function __toString() {
1637                 return "{$this->getCodeString()}: {$this->getMessage()}";
1638         }
1639 }
1640
1641 /**
1642  * For really cool vim folding this needs to be at the end:
1643  * vim: foldmarker=@{,@} foldmethod=marker
1644  */