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
  68                 // Write modules
  69                 'purge' => 'ApiPurge',
  70                 'setnotificationtimestamp' => 'ApiSetNotificationTimestamp',
  71                 'rollback' => 'ApiRollback',
  72                 'delete' => 'ApiDelete',
  73                 'undelete' => 'ApiUndelete',
  74                 'protect' => 'ApiProtect',
  75                 'block' => 'ApiBlock',
  76                 'unblock' => 'ApiUnblock',
  77                 'move' => 'ApiMove',
  78                 'edit' => 'ApiEditPage',
  79                 'upload' => 'ApiUpload',
  80                 'filerevert' => 'ApiFileRevert',
  81                 'emailuser' => 'ApiEmailUser',
  82                 'watch' => 'ApiWatch',
  83                 'patrol' => 'ApiPatrol',
  84                 'import' => 'ApiImport',
  85                 'clearhasmsg' => 'ApiClearHasMsg',
  86                 'userrights' => 'ApiUserrights',
  87                 'options' => 'ApiOptions',
  88                 'imagerotate' => 'ApiImageRotate',
  89                 'revisiondelete' => 'ApiRevisionDelete',
  90         );
  91
  92         /**
  93          * List of available formats: format name => format class
  94          */
  95         private static $Formats = array(
  96                 'json' => 'ApiFormatJson',
  97                 'jsonfm' => 'ApiFormatJson',
  98                 'php' => 'ApiFormatPhp',
  99                 'phpfm' => 'ApiFormatPhp',
 100                 'wddx' => 'ApiFormatWddx',
 101                 'wddxfm' => 'ApiFormatWddx',
 102                 'xml' => 'ApiFormatXml',
 103                 'xmlfm' => 'ApiFormatXml',
 104                 'yaml' => 'ApiFormatYaml',
 105                 'yamlfm' => 'ApiFormatYaml',
 106                 'rawfm' => 'ApiFormatJson',
 107                 'txt' => 'ApiFormatTxt',
 108                 'txtfm' => 'ApiFormatTxt',
 109                 'dbg' => 'ApiFormatDbg',
 110                 'dbgfm' => 'ApiFormatDbg',
 111                 'dump' => 'ApiFormatDump',
 112                 'dumpfm' => 'ApiFormatDump',
 113                 'none' => 'ApiFormatNone',
 114         );
 115
 116         // @codingStandardsIgnoreStart String contenation on "msg" not allowed to break long line
 117         /**
 118          * List of user roles that are specifically relevant to the API.
 119          * array( 'right' => array ( 'msg'    => 'Some message with a $1',
 120          *                           'params' => array ( $someVarToSubst ) ),
 121          *                          );
 122          */
 123         private static $mRights = array(
 124                 'writeapi' => array(
 125                         'msg' => 'right-writeapi',
 126                         'params' => array()
 127                 ),
 128                 'apihighlimits' => array(
 129                         'msg' => 'api-help-right-apihighlimits',
 130                         'params' => array( ApiBase::LIMIT_SML2, ApiBase::LIMIT_BIG2 )
 131                 )
 132         );
 133         // @codingStandardsIgnoreEnd
 134
 135         /**
 136          * @var ApiFormatBase
 137          */
 138         private $mPrinter;
 139
 140         private $mModuleMgr, $mResult;
 141         private $mAction;
 142         private $mEnableWrite;
 143         private $mInternalMode, $mSquidMaxage, $mModule;
 144
 145         private $mCacheMode = 'private';
 146         private $mCacheControl = array();
 147         private $mParamsUsed = array();
 148
 149         /**
 150          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 151          *
 152          * @param IContextSource|WebRequest $context If this is an instance of
 153          *    FauxRequest, errors are thrown and no printing occurs
 154          * @param bool $enableWrite Should be set to true if the api may modify data
 155          */
 156         public function __construct( $context = null, $enableWrite = false ) {
 157                 if ( $context === null ) {
 158                         $context = RequestContext::getMain();
 159                 } elseif ( $context instanceof WebRequest ) {
 160                         // BC for pre-1.19
 161                         $request = $context;
 162                         $context = RequestContext::getMain();
 163                 }
 164                 // We set a derivative context so we can change stuff later
 165                 $this->setContext( new DerivativeContext( $context ) );
 166
 167                 if ( isset( $request ) ) {
 168                         $this->getContext()->setRequest( $request );
 169                 }
 170
 171                 $this->mInternalMode = ( $this->getRequest() instanceof FauxRequest );
 172
 173                 // Special handling for the main module: $parent === $this
 174                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 175
 176                 if ( !$this->mInternalMode ) {
 177                         // Impose module restrictions.
 178                         // If the current user cannot read,
 179                         // Remove all modules other than login
 180                         global $wgUser;
 181
 182                         if ( $this->getVal( 'callback' ) !== null ) {
 183                                 // JSON callback allows cross-site reads.
 184                                 // For safety, strip user credentials.
 185                                 wfDebug( "API: stripping user credentials for JSON callback\n" );
 186                                 $wgUser = new User();
 187                                 $this->getContext()->setUser( $wgUser );
 188                         }
 189                 }
 190
 191                 $uselang = $this->getParameter( 'uselang' );
 192                 if ( $uselang === 'user' ) {
 193                         // Assume the parent context is going to return the user language
 194                         // for uselang=user (see T85635).
 195                 } else {
 196                         if ( $uselang === 'content' ) {
 197                                 global $wgContLang;
 198                                 $uselang = $wgContLang->getCode();
 199                         }
 200                         $code = RequestContext::sanitizeLangCode( $uselang );
 201                         $this->getContext()->setLanguage( $code );
 202                         if ( !$this->mInternalMode ) {
 203                                 global $wgLang;
 204                                 $wgLang = $this->getContext()->getLanguage();
 205                                 RequestContext::getMain()->setLanguage( $wgLang );
 206                         }
 207                 }
 208
 209                 $config = $this->getConfig();
 210                 $this->mModuleMgr = new ApiModuleManager( $this );
 211                 $this->mModuleMgr->addModules( self::$Modules, 'action' );
 212                 $this->mModuleMgr->addModules( $config->get( 'APIModules' ), 'action' );
 213                 $this->mModuleMgr->addModules( self::$Formats, 'format' );
 214                 $this->mModuleMgr->addModules( $config->get( 'APIFormatModules' ), 'format' );
 215
 216                 $this->mResult = new ApiResult( $this );
 217                 $this->mEnableWrite = $enableWrite;
 218
 219                 $this->mSquidMaxage = -1; // flag for executeActionWithErrorHandling()
 220                 $this->mCommit = false;
 221         }
 222
 223         /**
 224          * Return true if the API was started by other PHP code using FauxRequest
 225          * @return bool
 226          */
 227         public function isInternalMode() {
 228                 return $this->mInternalMode;
 229         }
 230
 231         /**
 232          * Get the ApiResult object associated with current request
 233          *
 234          * @return ApiResult
 235          */
 236         public function getResult() {
 237                 return $this->mResult;
 238         }
 239
 240         /**
 241          * Get the API module object. Only works after executeAction()
 242          *
 243          * @return ApiBase
 244          */
 245         public function getModule() {
 246                 return $this->mModule;
 247         }
 248
 249         /**
 250          * Get the result formatter object. Only works after setupExecuteAction()
 251          *
 252          * @return ApiFormatBase
 253          */
 254         public function getPrinter() {
 255                 return $this->mPrinter;
 256         }
 257
 258         /**
 259          * Set how long the response should be cached.
 260          *
 261          * @param int $maxage
 262          */
 263         public function setCacheMaxAge( $maxage ) {
 264                 $this->setCacheControl( array(
 265                         'max-age' => $maxage,
 266                         's-maxage' => $maxage
 267                 ) );
 268         }
 269
 270         /**
 271          * Set the type of caching headers which will be sent.
 272          *
 273          * @param string $mode One of:
 274          *    - 'public':     Cache this object in public caches, if the maxage or smaxage
 275          *         parameter is set, or if setCacheMaxAge() was called. If a maximum age is
 276          *         not provided by any of these means, the object will be private.
 277          *    - 'private':    Cache this object only in private client-side caches.
 278          *    - 'anon-public-user-private': Make this object cacheable for logged-out
 279          *         users, but private for logged-in users. IMPORTANT: If this is set, it must be
 280          *         set consistently for a given URL, it cannot be set differently depending on
 281          *         things like the contents of the database, or whether the user is logged in.
 282          *
 283          *  If the wiki does not allow anonymous users to read it, the mode set here
 284          *  will be ignored, and private caching headers will always be sent. In other words,
 285          *  the "public" mode is equivalent to saying that the data sent is as public as a page
 286          *  view.
 287          *
 288          *  For user-dependent data, the private mode should generally be used. The
 289          *  anon-public-user-private mode should only be used where there is a particularly
 290          *  good performance reason for caching the anonymous response, but where the
 291          *  response to logged-in users may differ, or may contain private data.
 292          *
 293          *  If this function is never called, then the default will be the private mode.
 294          */
 295         public function setCacheMode( $mode ) {
 296                 if ( !in_array( $mode, array( 'private', 'public', 'anon-public-user-private' ) ) ) {
 297                         wfDebug( __METHOD__ . ": unrecognised cache mode \"$mode\"\n" );
 298
 299                         // Ignore for forwards-compatibility
 300                         return;
 301                 }
 302
 303                 if ( !User::isEveryoneAllowed( 'read' ) ) {
 304                         // Private wiki, only private headers
 305                         if ( $mode !== 'private' ) {
 306                                 wfDebug( __METHOD__ . ": ignoring request for $mode cache mode, private wiki\n" );
 307
 308                                 return;
 309                         }
 310                 }
 311
 312                 if ( $mode === 'public' && $this->getParameter( 'uselang' ) === 'user' ) {
 313                         // User language is used for i18n, so we don't want to publicly
 314                         // cache. Anons are ok, because if they have non-default language
 315                         // then there's an appropriate Vary header set by whatever set
 316                         // their non-default language.
 317                         wfDebug( __METHOD__ . ": downgrading cache mode 'public' to " .
 318                                 "'anon-public-user-private' due to uselang=user\n" );
 319                         $mode = 'anon-public-user-private';
 320                 }
 321
 322                 wfDebug( __METHOD__ . ": setting cache mode $mode\n" );
 323                 $this->mCacheMode = $mode;
 324         }
 325
 326         /**
 327          * Set directives (key/value pairs) for the Cache-Control header.
 328          * Boolean values will be formatted as such, by including or omitting
 329          * without an equals sign.
 330          *
 331          * Cache control values set here will only be used if the cache mode is not
 332          * private, see setCacheMode().
 333          *
 334          * @param array $directives
 335          */
 336         public function setCacheControl( $directives ) {
 337                 $this->mCacheControl = $directives + $this->mCacheControl;
 338         }
 339
 340         /**
 341          * Create an instance of an output formatter by its name
 342          *
 343          * @param string $format
 344          *
 345          * @return ApiFormatBase
 346          */
 347         public function createPrinterByName( $format ) {
 348                 $printer = $this->mModuleMgr->getModule( $format, 'format' );
 349                 if ( $printer === null ) {
 350                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 351                 }
 352
 353                 return $printer;
 354         }
 355
 356         /**
 357          * Execute api request. Any errors will be handled if the API was called by the remote client.
 358          */
 359         public function execute() {
 360                 $this->profileIn();
 361                 if ( $this->mInternalMode ) {
 362                         $this->executeAction();
 363                 } else {
 364                         $this->executeActionWithErrorHandling();
 365                 }
 366
 367                 $this->profileOut();
 368         }
 369
 370         /**
 371          * Execute an action, and in case of an error, erase whatever partial results
 372          * have been accumulated, and replace it with an error message and a help screen.
 373          */
 374         protected function executeActionWithErrorHandling() {
 375                 // Verify the CORS header before executing the action
 376                 if ( !$this->handleCORS() ) {
 377                         // handleCORS() has sent a 403, abort
 378                         return;
 379                 }
 380
 381                 // Exit here if the request method was OPTIONS
 382                 // (assume there will be a followup GET or POST)
 383                 if ( $this->getRequest()->getMethod() === 'OPTIONS' ) {
 384                         return;
 385                 }
 386
 387                 // In case an error occurs during data output,
 388                 // clear the output buffer and print just the error information
 389                 ob_start();
 390
 391                 $t = microtime( true );
 392                 try {
 393                         $this->executeAction();
 394                 } catch ( Exception $e ) {
 395                         $this->handleException( $e );
 396                 }
 397
 398                 // Log the request whether or not there was an error
 399                 $this->logRequest( microtime( true ) - $t );
 400
 401                 // Send cache headers after any code which might generate an error, to
 402                 // avoid sending public cache headers for errors.
 403                 $this->sendCacheHeaders();
 404
 405                 ob_end_flush();
 406         }
 407
 408         /**
 409          * Handle an exception as an API response
 410          *
 411          * @since 1.23
 412          * @param Exception $e
 413          */
 414         protected function handleException( Exception $e ) {
 415                 // Bug 63145: Rollback any open database transactions
 416                 if ( !( $e instanceof UsageException ) ) {
 417                         // UsageExceptions are intentional, so don't rollback if that's the case
 418                         MWExceptionHandler::rollbackMasterChangesAndLog( $e );
 419                 }
 420
 421                 // Allow extra cleanup and logging
 422                 Hooks::run( 'ApiMain::onException', array( $this, $e ) );
 423
 424                 // Log it
 425                 if ( !( $e instanceof UsageException ) ) {
 426                         MWExceptionHandler::logException( $e );
 427                 }
 428
 429                 // Handle any kind of exception by outputting properly formatted error message.
 430                 // If this fails, an unhandled exception should be thrown so that global error
 431                 // handler will process and log it.
 432
 433                 $errCode = $this->substituteResultWithError( $e );
 434
 435                 // Error results should not be cached
 436                 $this->setCacheMode( 'private' );
 437
 438                 $response = $this->getRequest()->response();
 439                 $headerStr = 'MediaWiki-API-Error: ' . $errCode;
 440                 if ( $e->getCode() === 0 ) {
 441                         $response->header( $headerStr );
 442                 } else {
 443                         $response->header( $headerStr, true, $e->getCode() );
 444                 }
 445
 446                 // Reset and print just the error message
 447                 ob_clean();
 448
 449                 // If the error occurred during printing, do a printer->profileOut()
 450                 $this->mPrinter->safeProfileOut();
 451                 $this->printResult( true );
 452         }
 453
 454         /**
 455          * Handle an exception from the ApiBeforeMain hook.
 456          *
 457          * This tries to print the exception as an API response, to be more
 458          * friendly to clients. If it fails, it will rethrow the exception.
 459          *
 460          * @since 1.23
 461          * @param Exception $e
 462          * @throws Exception
 463          */
 464         public static function handleApiBeforeMainException( Exception $e ) {
 465                 ob_start();
 466
 467                 try {
 468                         $main = new self( RequestContext::getMain(), false );
 469                         $main->handleException( $e );
 470                 } catch ( Exception $e2 ) {
 471                         // Nope, even that didn't work. Punt.
 472                         throw $e;
 473                 }
 474
 475                 // Log the request and reset cache headers
 476                 $main->logRequest( 0 );
 477                 $main->sendCacheHeaders();
 478
 479                 ob_end_flush();
 480         }
 481
 482         /**
 483          * Check the &origin= query parameter against the Origin: HTTP header and respond appropriately.
 484          *
 485          * If no origin parameter is present, nothing happens.
 486          * If an origin parameter is present but doesn't match the Origin header, a 403 status code
 487          * is set and false is returned.
 488          * If the parameter and the header do match, the header is checked against $wgCrossSiteAJAXdomains
 489          * and $wgCrossSiteAJAXdomainExceptions, and if the origin qualifies, the appropriate CORS
 490          * headers are set.
 491          * http://www.w3.org/TR/cors/#resource-requests
 492          * http://www.w3.org/TR/cors/#resource-preflight-requests
 493          *
 494          * @return bool False if the caller should abort (403 case), true otherwise (all other cases)
 495          */
 496         protected function handleCORS() {
 497                 $originParam = $this->getParameter( 'origin' ); // defaults to null
 498                 if ( $originParam === null ) {
 499                         // No origin parameter, nothing to do
 500                         return true;
 501                 }
 502
 503                 $request = $this->getRequest();
 504                 $response = $request->response();
 505
 506                 // Origin: header is a space-separated list of origins, check all of them
 507                 $originHeader = $request->getHeader( 'Origin' );
 508                 if ( $originHeader === false ) {
 509                         $origins = array();
 510                 } else {
 511                         $originHeader = trim( $originHeader );
 512                         $origins = preg_split( '/\s+/', $originHeader );
 513                 }
 514
 515                 if ( !in_array( $originParam, $origins ) ) {
 516                         // origin parameter set but incorrect
 517                         // Send a 403 response
 518                         $message = HttpStatus::getMessage( 403 );
 519                         $response->header( "HTTP/1.1 403 $message", true, 403 );
 520                         $response->header( 'Cache-Control: no-cache' );
 521                         echo "'origin' parameter does not match Origin header\n";
 522
 523                         return false;
 524                 }
 525
 526                 $config = $this->getConfig();
 527                 $matchOrigin = count( $origins ) === 1 && self::matchOrigin(
 528                         $originParam,
 529                         $config->get( 'CrossSiteAJAXdomains' ),
 530                         $config->get( 'CrossSiteAJAXdomainExceptions' )
 531                 );
 532
 533                 if ( $matchOrigin ) {
 534                         $requestedMethod = $request->getHeader( 'Access-Control-Request-Method' );
 535                         $preflight = $request->getMethod() === 'OPTIONS' && $requestedMethod !== false;
 536                         if ( $preflight ) {
 537                                 // This is a CORS preflight request
 538                                 if ( $requestedMethod !== 'POST' && $requestedMethod !== 'GET' ) {
 539                                         // If method is not a case-sensitive match, do not set any additional headers and terminate.
 540                                         return true;
 541                                 }
 542                                 // We allow the actual request to send the following headers
 543                                 $requestedHeaders = $request->getHeader( 'Access-Control-Request-Headers' );
 544                                 if ( $requestedHeaders !== false ) {
 545                                         if ( !self::matchRequestedHeaders( $requestedHeaders ) ) {
 546                                                 return true;
 547                                         }
 548                                         $response->header( 'Access-Control-Allow-Headers: ' . $requestedHeaders );
 549                                 }
 550
 551                                 // We only allow the actual request to be GET or POST
 552                                 $response->header( 'Access-Control-Allow-Methods: POST, GET' );
 553                         }
 554
 555                         $response->header( "Access-Control-Allow-Origin: $originHeader" );
 556                         $response->header( 'Access-Control-Allow-Credentials: true' );
 557
 558                         if ( !$preflight ) {
 559                                 $response->header( 'Access-Control-Expose-Headers: MediaWiki-API-Error, Retry-After, X-Database-Lag' );
 560                         }
 561                 }
 562
 563                 $this->getOutput()->addVaryHeader( 'Origin' );
 564                 return true;
 565         }
 566
 567         /**
 568          * Attempt to match an Origin header against a set of rules and a set of exceptions
 569          * @param string $value Origin header
 570          * @param array $rules Set of wildcard rules
 571          * @param array $exceptions Set of wildcard rules
 572          * @return bool True if $value matches a rule in $rules and doesn't match
 573          *    any rules in $exceptions, false otherwise
 574          */
 575         protected static function matchOrigin( $value, $rules, $exceptions ) {
 576                 foreach ( $rules as $rule ) {
 577                         if ( preg_match( self::wildcardToRegex( $rule ), $value ) ) {
 578                                 // Rule matches, check exceptions
 579                                 foreach ( $exceptions as $exc ) {
 580                                         if ( preg_match( self::wildcardToRegex( $exc ), $value ) ) {
 581                                                 return false;
 582                                         }
 583                                 }
 584
 585                                 return true;
 586                         }
 587                 }
 588
 589                 return false;
 590         }
 591
 592         /**
 593          * Attempt to validate the value of Access-Control-Request-Headers against a list
 594          * of headers that we allow the follow up request to send.
 595          *
 596          * @param string $requestedHeaders Comma seperated list of HTTP headers
 597          * @return bool True if all requested headers are in the list of allowed headers
 598          */
 599         protected static function matchRequestedHeaders( $requestedHeaders ) {
 600                 if ( trim( $requestedHeaders ) === '' ) {
 601                         return true;
 602                 }
 603                 $requestedHeaders = explode( ',', $requestedHeaders );
 604                 $allowedAuthorHeaders = array_flip( array(
 605                         /* simple headers (see spec) */
 606                         'accept',
 607                         'accept-language',
 608                         'content-language',
 609                         'content-type',
 610                         /* non-authorable headers in XHR, which are however requested by some UAs */
 611                         'accept-encoding',
 612                         'dnt',
 613                         'origin',
 614                         /* MediaWiki whitelist */
 615                         'api-user-agent',
 616                 ) );
 617                 foreach ( $requestedHeaders as $rHeader ) {
 618                         $rHeader = strtolower( trim( $rHeader ) );
 619                         if ( !isset( $allowedAuthorHeaders[$rHeader] ) ) {
 620                                 wfDebugLog( 'api', 'CORS preflight failed on requested header: ' . $rHeader );
 621                                 return false;
 622                         }
 623                 }
 624                 return true;
 625         }
 626
 627         /**
 628          * Helper function to convert wildcard string into a regex
 629          * '*' => '.*?'
 630          * '?' => '.'
 631          *
 632          * @param string $wildcard String with wildcards
 633          * @return string Regular expression
 634          */
 635         protected static function wildcardToRegex( $wildcard ) {
 636                 $wildcard = preg_quote( $wildcard, '/' );
 637                 $wildcard = str_replace(
 638                         array( '\*', '\?' ),
 639                         array( '.*?', '.' ),
 640                         $wildcard
 641                 );
 642
 643                 return "/^https?:\/\/$wildcard$/";
 644         }
 645
 646         protected function sendCacheHeaders() {
 647                 $response = $this->getRequest()->response();
 648                 $out = $this->getOutput();
 649
 650                 $config = $this->getConfig();
 651
 652                 if ( $config->get( 'VaryOnXFP' ) ) {
 653                         $out->addVaryHeader( 'X-Forwarded-Proto' );
 654                 }
 655
 656                 if ( $this->mCacheMode == 'private' ) {
 657                         $response->header( 'Cache-Control: private' );
 658                         return;
 659                 }
 660
 661                 $useXVO = $config->get( 'UseXVO' );
 662                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 663                         $out->addVaryHeader( 'Cookie' );
 664                         $response->header( $out->getVaryHeader() );
 665                         if ( $useXVO ) {
 666                                 $response->header( $out->getXVO() );
 667                                 if ( $out->haveCacheVaryCookies() ) {
 668                                         // Logged in, mark this request private
 669                                         $response->header( 'Cache-Control: private' );
 670                                         return;
 671                                 }
 672                                 // Logged out, send normal public headers below
 673                         } elseif ( session_id() != '' ) {
 674                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 675                                 // Mark request private
 676                                 $response->header( 'Cache-Control: private' );
 677
 678                                 return;
 679                         } // else no XVO and anonymous, send public headers below
 680                 }
 681
 682                 // Send public headers
 683                 $response->header( $out->getVaryHeader() );
 684                 if ( $useXVO ) {
 685                         $response->header( $out->getXVO() );
 686                 }
 687
 688                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 689                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 690                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 691                 }
 692                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 693                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 694                 }
 695
 696                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 697                         // Public cache not requested
 698                         // Sending a Vary header in this case is harmless, and protects us
 699                         // against conditional calls of setCacheMaxAge().
 700                         $response->header( 'Cache-Control: private' );
 701
 702                         return;
 703                 }
 704
 705                 $this->mCacheControl['public'] = true;
 706
 707                 // Send an Expires header
 708                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 709                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 710                 $response->header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 711
 712                 // Construct the Cache-Control header
 713                 $ccHeader = '';
 714                 $separator = '';
 715                 foreach ( $this->mCacheControl as $name => $value ) {
 716                         if ( is_bool( $value ) ) {
 717                                 if ( $value ) {
 718                                         $ccHeader .= $separator . $name;
 719                                         $separator = ', ';
 720                                 }
 721                         } else {
 722                                 $ccHeader .= $separator . "$name=$value";
 723                                 $separator = ', ';
 724                         }
 725                 }
 726
 727                 $response->header( "Cache-Control: $ccHeader" );
 728         }
 729
 730         /**
 731          * Replace the result data with the information about an exception.
 732          * Returns the error code
 733          * @param Exception $e
 734          * @return string
 735          */
 736         protected function substituteResultWithError( $e ) {
 737                 $result = $this->getResult();
 738
 739                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 740                 if ( !isset( $this->mPrinter ) ) {
 741                         // The printer has not been created yet. Try to manually get formatter value.
 742                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 743                         if ( !$this->mModuleMgr->isDefined( $value, 'format' ) ) {
 744                                 $value = self::API_DEFAULT_FORMAT;
 745                         }
 746
 747                         $this->mPrinter = $this->createPrinterByName( $value );
 748                 }
 749
 750                 // Printer may not be able to handle errors. This is particularly
 751                 // likely if the module returns something for getCustomPrinter().
 752                 if ( !$this->mPrinter->canPrintErrors() ) {
 753                         $this->mPrinter->safeProfileOut();
 754                         $this->mPrinter = $this->createPrinterByName( self::API_DEFAULT_FORMAT );
 755                 }
 756
 757                 // Update raw mode flag for the selected printer.
 758                 $result->setRawMode( $this->mPrinter->getNeedsRawData() );
 759
 760                 $config = $this->getConfig();
 761
 762                 if ( $e instanceof UsageException ) {
 763                         // User entered incorrect parameters - generate error response
 764                         $errMessage = $e->getMessageArray();
 765                         $link = wfExpandUrl( wfScript( 'api' ) );
 766                         ApiResult::setContent( $errMessage, "See $link for API usage" );
 767                 } else {
 768                         // Something is seriously wrong
 769                         if ( ( $e instanceof DBQueryError ) && !$config->get( 'ShowSQLErrors' ) ) {
 770                                 $info = 'Database query error';
 771                         } else {
 772                                 $info = "Exception Caught: {$e->getMessage()}";
 773                         }
 774
 775                         $errMessage = array(
 776                                 'code' => 'internal_api_error_' . get_class( $e ),
 777                                 'info' => '[' . MWExceptionHandler::getLogId( $e ) . '] ' . $info,
 778                         );
 779                         if ( $config->get( 'ShowExceptionDetails' ) ) {
 780                                 ApiResult::setContent(
 781                                         $errMessage,
 782                                         MWExceptionHandler::getRedactedTraceAsString( $e )
 783                                 );
 784                         }
 785                 }
 786
 787                 // Remember all the warnings to re-add them later
 788                 $oldResult = $result->getData();
 789                 $warnings = isset( $oldResult['warnings'] ) ? $oldResult['warnings'] : null;
 790
 791                 $result->reset();
 792                 // Re-add the id
 793                 $requestid = $this->getParameter( 'requestid' );
 794                 if ( !is_null( $requestid ) ) {
 795                         $result->addValue( null, 'requestid', $requestid, ApiResult::NO_SIZE_CHECK );
 796                 }
 797                 if ( $config->get( 'ShowHostnames' ) ) {
 798                         // servedby is especially useful when debugging errors
 799                         $result->addValue( null, 'servedby', wfHostName(), ApiResult::NO_SIZE_CHECK );
 800                 }
 801                 if ( $warnings !== null ) {
 802                         $result->addValue( null, 'warnings', $warnings, ApiResult::NO_SIZE_CHECK );
 803                 }
 804
 805                 $result->addValue( null, 'error', $errMessage, ApiResult::NO_SIZE_CHECK );
 806
 807                 return $errMessage['code'];
 808         }
 809
 810         /**
 811          * Set up for the execution.
 812          * @return array
 813          */
 814         protected function setupExecuteAction() {
 815                 // First add the id to the top element
 816                 $result = $this->getResult();
 817                 $requestid = $this->getParameter( 'requestid' );
 818                 if ( !is_null( $requestid ) ) {
 819                         $result->addValue( null, 'requestid', $requestid );
 820                 }
 821
 822                 if ( $this->getConfig()->get( 'ShowHostnames' ) ) {
 823                         $servedby = $this->getParameter( 'servedby' );
 824                         if ( $servedby ) {
 825                                 $result->addValue( null, 'servedby', wfHostName() );
 826                         }
 827                 }
 828
 829                 if ( $this->getParameter( 'curtimestamp' ) ) {
 830                         $result->addValue( null, 'curtimestamp', wfTimestamp( TS_ISO_8601, time() ),
 831                                 ApiResult::NO_SIZE_CHECK );
 832                 }
 833
 834                 $params = $this->extractRequestParams();
 835
 836                 $this->mAction = $params['action'];
 837
 838                 if ( !is_string( $this->mAction ) ) {
 839                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 840                 }
 841
 842                 return $params;
 843         }
 844
 845         /**
 846          * Set up the module for response
 847          * @return ApiBase The module that will handle this action
 848          * @throws MWException
 849          * @throws UsageException
 850          */
 851         protected function setupModule() {
 852                 // Instantiate the module requested by the user
 853                 $module = $this->mModuleMgr->getModule( $this->mAction, 'action' );
 854                 if ( $module === null ) {
 855                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 856                 }
 857                 $moduleParams = $module->extractRequestParams();
 858
 859                 // Check token, if necessary
 860                 if ( $module->needsToken() === true ) {
 861                         throw new MWException(
 862                                 "Module '{$module->getModuleName()}' must be updated for the new token handling. " .
 863                                 "See documentation for ApiBase::needsToken for details."
 864                         );
 865                 }
 866                 if ( $module->needsToken() ) {
 867                         if ( !$module->mustBePosted() ) {
 868                                 throw new MWException(
 869                                         "Module '{$module->getModuleName()}' must require POST to use tokens."
 870                                 );
 871                         }
 872
 873                         if ( !isset( $moduleParams['token'] ) ) {
 874                                 $this->dieUsageMsg( array( 'missingparam', 'token' ) );
 875                         }
 876
 877                         if ( !$this->getConfig()->get( 'DebugAPI' ) &&
 878                                 array_key_exists(
 879                                         $module->encodeParamName( 'token' ),
 880                                         $this->getRequest()->getQueryValues()
 881                                 )
 882                         ) {
 883                                 $this->dieUsage(
 884                                         "The '{$module->encodeParamName( 'token' )}' parameter was found in the query string, but must be in the POST body",
 885                                         'mustposttoken'
 886                                 );
 887                         }
 888
 889                         if ( !$module->validateToken( $moduleParams['token'], $moduleParams ) ) {
 890                                 $this->dieUsageMsg( 'sessionfailure' );
 891                         }
 892                 }
 893
 894                 return $module;
 895         }
 896
 897         /**
 898          * Check the max lag if necessary
 899          * @param ApiBase $module Api module being used
 900          * @param array $params Array an array containing the request parameters.
 901          * @return bool True on success, false should exit immediately
 902          */
 903         protected function checkMaxLag( $module, $params ) {
 904                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
 905                         // Check for maxlag
 906                         $maxLag = $params['maxlag'];
 907                         list( $host, $lag ) = wfGetLB()->getMaxLag();
 908                         if ( $lag > $maxLag ) {
 909                                 $response = $this->getRequest()->response();
 910
 911                                 $response->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
 912                                 $response->header( 'X-Database-Lag: ' . intval( $lag ) );
 913
 914                                 if ( $this->getConfig()->get( 'ShowHostnames' ) ) {
 915                                         $this->dieUsage( "Waiting for $host: $lag seconds lagged", 'maxlag' );
 916                                 }
 917
 918                                 $this->dieUsage( "Waiting for a database server: $lag seconds lagged", 'maxlag' );
 919                         }
 920                 }
 921
 922                 return true;
 923         }
 924
 925         /**
 926          * Check for sufficient permissions to execute
 927          * @param ApiBase $module An Api module
 928          */
 929         protected function checkExecutePermissions( $module ) {
 930                 $user = $this->getUser();
 931                 if ( $module->isReadMode() && !User::isEveryoneAllowed( 'read' ) &&
 932                         !$user->isAllowed( 'read' )
 933                 ) {
 934                         $this->dieUsageMsg( 'readrequired' );
 935                 }
 936                 if ( $module->isWriteMode() ) {
 937                         if ( !$this->mEnableWrite ) {
 938                                 $this->dieUsageMsg( 'writedisabled' );
 939                         }
 940                         if ( !$user->isAllowed( 'writeapi' ) ) {
 941                                 $this->dieUsageMsg( 'writerequired' );
 942                         }
 943                         if ( wfReadOnly() ) {
 944                                 $this->dieReadOnly();
 945                         }
 946                 }
 947
 948                 // Allow extensions to stop execution for arbitrary reasons.
 949                 $message = false;
 950                 if ( !Hooks::run( 'ApiCheckCanExecute', array( $module, $user, &$message ) ) ) {
 951                         $this->dieUsageMsg( $message );
 952                 }
 953         }
 954
 955         /**
 956          * Check asserts of the user's rights
 957          * @param array $params
 958          */
 959         protected function checkAsserts( $params ) {
 960                 if ( isset( $params['assert'] ) ) {
 961                         $user = $this->getUser();
 962                         switch ( $params['assert'] ) {
 963                                 case 'user':
 964                                         if ( $user->isAnon() ) {
 965                                                 $this->dieUsage( 'Assertion that the user is logged in failed', 'assertuserfailed' );
 966                                         }
 967                                         break;
 968                                 case 'bot':
 969                                         if ( !$user->isAllowed( 'bot' ) ) {
 970                                                 $this->dieUsage( 'Assertion that the user has the bot right failed', 'assertbotfailed' );
 971                                         }
 972                                         break;
 973                         }
 974                 }
 975         }
 976
 977         /**
 978          * Check POST for external response and setup result printer
 979          * @param ApiBase $module An Api module
 980          * @param array $params An array with the request parameters
 981          */
 982         protected function setupExternalResponse( $module, $params ) {
 983                 if ( !$this->getRequest()->wasPosted() && $module->mustBePosted() ) {
 984                         // Module requires POST. GET request might still be allowed
 985                         // if $wgDebugApi is true, otherwise fail.
 986                         $this->dieUsageMsgOrDebug( array( 'mustbeposted', $this->mAction ) );
 987                 }
 988
 989                 // See if custom printer is used
 990                 $this->mPrinter = $module->getCustomPrinter();
 991                 if ( is_null( $this->mPrinter ) ) {
 992                         // Create an appropriate printer
 993                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
 994                 }
 995
 996                 if ( $this->mPrinter->getNeedsRawData() ) {
 997                         $this->getResult()->setRawMode();
 998                 }
 999         }
1000
1001         /**
1002          * Execute the actual module, without any error handling
1003          */
1004         protected function executeAction() {
1005                 $params = $this->setupExecuteAction();
1006                 $module = $this->setupModule();
1007                 $this->mModule = $module;
1008
1009                 $this->checkExecutePermissions( $module );
1010
1011                 if ( !$this->checkMaxLag( $module, $params ) ) {
1012                         return;
1013                 }
1014
1015                 if ( !$this->mInternalMode ) {
1016                         $this->setupExternalResponse( $module, $params );
1017                 }
1018
1019                 $this->checkAsserts( $params );
1020
1021                 // Execute
1022                 $module->profileIn();
1023                 $module->execute();
1024                 Hooks::run( 'APIAfterExecute', array( &$module ) );
1025                 $module->profileOut();
1026
1027                 $this->reportUnusedParams();
1028
1029                 if ( !$this->mInternalMode ) {
1030                         //append Debug information
1031                         MWDebug::appendDebugInfoToApiResult( $this->getContext(), $this->getResult() );
1032
1033                         // Print result data
1034                         $this->printResult( false );
1035                 }
1036         }
1037
1038         /**
1039          * Log the preceding request
1040          * @param int $time Time in seconds
1041          */
1042         protected function logRequest( $time ) {
1043                 $request = $this->getRequest();
1044                 $milliseconds = $time === null ? '?' : round( $time * 1000 );
1045                 $s = 'API' .
1046                         ' ' . $request->getMethod() .
1047                         ' ' . wfUrlencode( str_replace( ' ', '_', $this->getUser()->getName() ) ) .
1048                         ' ' . $request->getIP() .
1049                         ' T=' . $milliseconds . 'ms';
1050                 foreach ( $this->getParamsUsed() as $name ) {
1051                         $value = $request->getVal( $name );
1052                         if ( $value === null ) {
1053                                 continue;
1054                         }
1055                         $s .= ' ' . $name . '=';
1056                         if ( strlen( $value ) > 256 ) {
1057                                 $encValue = $this->encodeRequestLogValue( substr( $value, 0, 256 ) );
1058                                 $s .= $encValue . '[...]';
1059                         } else {
1060                                 $s .= $this->encodeRequestLogValue( $value );
1061                         }
1062                 }
1063                 $s .= "\n";
1064                 wfDebugLog( 'api', $s, 'private' );
1065         }
1066
1067         /**
1068          * Encode a value in a format suitable for a space-separated log line.
1069          * @param string $s
1070          * @return string
1071          */
1072         protected function encodeRequestLogValue( $s ) {
1073                 static $table;
1074                 if ( !$table ) {
1075                         $chars = ';@$!*(),/:';
1076                         $numChars = strlen( $chars );
1077                         for ( $i = 0; $i < $numChars; $i++ ) {
1078                                 $table[rawurlencode( $chars[$i] )] = $chars[$i];
1079                         }
1080                 }
1081
1082                 return strtr( rawurlencode( $s ), $table );
1083         }
1084
1085         /**
1086          * Get the request parameters used in the course of the preceding execute() request
1087          * @return array
1088          */
1089         protected function getParamsUsed() {
1090                 return array_keys( $this->mParamsUsed );
1091         }
1092
1093         /**
1094          * Get a request value, and register the fact that it was used, for logging.
1095          * @param string $name
1096          * @param mixed $default
1097          * @return mixed
1098          */
1099         public function getVal( $name, $default = null ) {
1100                 $this->mParamsUsed[$name] = true;
1101
1102                 $ret = $this->getRequest()->getVal( $name );
1103                 if ( $ret === null ) {
1104                         if ( $this->getRequest()->getArray( $name ) !== null ) {
1105                                 // See bug 10262 for why we don't just join( '|', ... ) the
1106                                 // array.
1107                                 $this->setWarning(
1108                                         "Parameter '$name' uses unsupported PHP array syntax"
1109                                 );
1110                         }
1111                         $ret = $default;
1112                 }
1113                 return $ret;
1114         }
1115
1116         /**
1117          * Get a boolean request value, and register the fact that the parameter
1118          * was used, for logging.
1119          * @param string $name
1120          * @return bool
1121          */
1122         public function getCheck( $name ) {
1123                 return $this->getVal( $name, null ) !== null;
1124         }
1125
1126         /**
1127          * Get a request upload, and register the fact that it was used, for logging.
1128          *
1129          * @since 1.21
1130          * @param string $name Parameter name
1131          * @return WebRequestUpload
1132          */
1133         public function getUpload( $name ) {
1134                 $this->mParamsUsed[$name] = true;
1135
1136                 return $this->getRequest()->getUpload( $name );
1137         }
1138
1139         /**
1140          * Report unused parameters, so the client gets a hint in case it gave us parameters we don't know,
1141          * for example in case of spelling mistakes or a missing 'g' prefix for generators.
1142          */
1143         protected function reportUnusedParams() {
1144                 $paramsUsed = $this->getParamsUsed();
1145                 $allParams = $this->getRequest()->getValueNames();
1146
1147                 if ( !$this->mInternalMode ) {
1148                         // Printer has not yet executed; don't warn that its parameters are unused
1149                         $printerParams = array_map(
1150                                 array( $this->mPrinter, 'encodeParamName' ),
1151                                 array_keys( $this->mPrinter->getFinalParams() ?: array() )
1152                         );
1153                         $unusedParams = array_diff( $allParams, $paramsUsed, $printerParams );
1154                 } else {
1155                         $unusedParams = array_diff( $allParams, $paramsUsed );
1156                 }
1157
1158                 if ( count( $unusedParams ) ) {
1159                         $s = count( $unusedParams ) > 1 ? 's' : '';
1160                         $this->setWarning( "Unrecognized parameter$s: '" . implode( $unusedParams, "', '" ) . "'" );
1161                 }
1162         }
1163
1164         /**
1165          * Print results using the current printer
1166          *
1167          * @param bool $isError
1168          */
1169         protected function printResult( $isError ) {
1170                 if ( $this->getConfig()->get( 'DebugAPI' ) !== false ) {
1171                         $this->setWarning( 'SECURITY WARNING: $wgDebugAPI is enabled' );
1172                 }
1173
1174                 $this->getResult()->cleanUpUTF8();
1175                 $printer = $this->mPrinter;
1176                 $printer->profileIn();
1177
1178                 $printer->initPrinter( false );
1179
1180                 $printer->execute();
1181                 $printer->closePrinter();
1182                 $printer->profileOut();
1183         }
1184
1185         /**
1186          * @return bool
1187          */
1188         public function isReadMode() {
1189                 return false;
1190         }
1191
1192         /**
1193          * See ApiBase for description.
1194          *
1195          * @return array
1196          */
1197         public function getAllowedParams() {
1198                 return array(
1199                         'action' => array(
1200                                 ApiBase::PARAM_DFLT => 'help',
1201                                 ApiBase::PARAM_TYPE => 'submodule',
1202                         ),
1203                         'format' => array(
1204                                 ApiBase::PARAM_DFLT => ApiMain::API_DEFAULT_FORMAT,
1205                                 ApiBase::PARAM_TYPE => 'submodule',
1206                         ),
1207                         'maxlag' => array(
1208                                 ApiBase::PARAM_TYPE => 'integer'
1209                         ),
1210                         'smaxage' => array(
1211                                 ApiBase::PARAM_TYPE => 'integer',
1212                                 ApiBase::PARAM_DFLT => 0
1213                         ),
1214                         'maxage' => array(
1215                                 ApiBase::PARAM_TYPE => 'integer',
1216                                 ApiBase::PARAM_DFLT => 0
1217                         ),
1218                         'assert' => array(
1219                                 ApiBase::PARAM_TYPE => array( 'user', 'bot' )
1220                         ),
1221                         'requestid' => null,
1222                         'servedby' => false,
1223                         'curtimestamp' => false,
1224                         'origin' => null,
1225                         'uselang' => array(
1226                                 ApiBase::PARAM_DFLT => 'user',
1227                         ),
1228                 );
1229         }
1230
1231         /** @see ApiBase::getExamplesMessages() */
1232         protected function getExamplesMessages() {
1233                 return array(
1234                         'action=help'
1235                                 => 'apihelp-help-example-main',
1236                         'action=help&recursivesubmodules=1'
1237                                 => 'apihelp-help-example-recursive',
1238                 );
1239         }
1240
1241         public function modifyHelp( array &$help, array $options ) {
1242                 // Wish PHP had an "array_insert_before". Instead, we have to manually
1243                 // reindex the array to get 'permissions' in the right place.
1244                 $oldHelp = $help;
1245                 $help = array();
1246                 foreach ( $oldHelp as $k => $v ) {
1247                         if ( $k === 'submodules' ) {
1248                                 $help['permissions'] = '';
1249                         }
1250                         $help[$k] = $v;
1251                 }
1252                 $help['credits'] = '';
1253
1254                 // Fill 'permissions'
1255                 $help['permissions'] .= Html::openElement( 'div',
1256                         array( 'class' => 'apihelp-block apihelp-permissions' ) );
1257                 $m = $this->msg( 'api-help-permissions' );
1258                 if ( !$m->isDisabled() ) {
1259                         $help['permissions'] .= Html::rawElement( 'div', array( 'class' => 'apihelp-block-head' ),
1260                                 $m->numParams( count( self::$mRights ) )->parse()
1261                         );
1262                 }
1263                 $help['permissions'] .= Html::openElement( 'dl' );
1264                 foreach ( self::$mRights as $right => $rightMsg ) {
1265                         $help['permissions'] .= Html::element( 'dt', null, $right );
1266
1267                         $rightMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )->parse();
1268                         $help['permissions'] .= Html::rawElement( 'dd', null, $rightMsg );
1269
1270                         $groups = array_map( function ( $group ) {
1271                                 return $group == '*' ? 'all' : $group;
1272                         }, User::getGroupsWithPermission( $right ) );
1273
1274                         $help['permissions'] .= Html::rawElement( 'dd', null,
1275                                 $this->msg( 'api-help-permissions-granted-to' )
1276                                         ->numParams( count( $groups ) )
1277                                         ->params( $this->getLanguage()->commaList( $groups ) )
1278                                         ->parse()
1279                         );
1280                 }
1281                 $help['permissions'] .= Html::closeElement( 'dl' );
1282                 $help['permissions'] .= Html::closeElement( 'div' );
1283
1284                 // Fill 'credits', if applicable
1285                 if ( empty( $options['nolead'] ) ) {
1286                         $help['credits'] .= Html::element( 'h' . min( 6, $options['headerlevel'] + 1 ),
1287                                 array( 'id' => '+credits', 'class' => 'apihelp-header' ),
1288                                 $this->msg( 'api-credits-header' )->parse()
1289                         );
1290                         $help['credits'] .= $this->msg( 'api-credits' )->useDatabase( false )->parseAsBlock();
1291                 }
1292         }
1293
1294         private $mCanApiHighLimits = null;
1295
1296         /**
1297          * Check whether the current user is allowed to use high limits
1298          * @return bool
1299          */
1300         public function canApiHighLimits() {
1301                 if ( !isset( $this->mCanApiHighLimits ) ) {
1302                         $this->mCanApiHighLimits = $this->getUser()->isAllowed( 'apihighlimits' );
1303                 }
1304
1305                 return $this->mCanApiHighLimits;
1306         }
1307
1308         /**
1309          * Overrides to return this instance's module manager.
1310          * @return ApiModuleManager
1311          */
1312         public function getModuleManager() {
1313                 return $this->mModuleMgr;
1314         }
1315
1316         /**
1317          * Fetches the user agent used for this request
1318          *
1319          * The value will be the combination of the 'Api-User-Agent' header (if
1320          * any) and the standard User-Agent header (if any).
1321          *
1322          * @return string
1323          */
1324         public function getUserAgent() {
1325                 return trim(
1326                         $this->getRequest()->getHeader( 'Api-user-agent' ) . ' ' .
1327                         $this->getRequest()->getHeader( 'User-agent' )
1328                 );
1329         }
1330
1331         /************************************************************************//**
1332          * @name   Deprecated
1333          * @{
1334          */
1335
1336         /**
1337          * Sets whether the pretty-printer should format *bold* and $italics$
1338          *
1339          * @deprecated since 1.25
1340          * @param bool $help
1341          */
1342         public function setHelp( $help = true ) {
1343                 wfDeprecated( __METHOD__, '1.25' );
1344                 $this->mPrinter->setHelp( $help );
1345         }
1346
1347         /**
1348          * Override the parent to generate help messages for all available modules.
1349          *
1350          * @deprecated since 1.25
1351          * @return string
1352          */
1353         public function makeHelpMsg() {
1354                 wfDeprecated( __METHOD__, '1.25' );
1355                 global $wgMemc;
1356                 $this->setHelp();
1357                 // Get help text from cache if present
1358                 $key = wfMemcKey( 'apihelp', $this->getModuleName(),
1359                         str_replace( ' ', '_', SpecialVersion::getVersion( 'nodb' ) ) );
1360
1361                 $cacheHelpTimeout = $this->getConfig()->get( 'APICacheHelpTimeout' );
1362                 if ( $cacheHelpTimeout > 0 ) {
1363                         $cached = $wgMemc->get( $key );
1364                         if ( $cached ) {
1365                                 return $cached;
1366                         }
1367                 }
1368                 $retval = $this->reallyMakeHelpMsg();
1369                 if ( $cacheHelpTimeout > 0 ) {
1370                         $wgMemc->set( $key, $retval, $cacheHelpTimeout );
1371                 }
1372
1373                 return $retval;
1374         }
1375
1376         /**
1377          * @deprecated since 1.25
1378          * @return mixed|string
1379          */
1380         public function reallyMakeHelpMsg() {
1381                 wfDeprecated( __METHOD__, '1.25' );
1382                 $this->setHelp();
1383
1384                 // Use parent to make default message for the main module
1385                 $msg = parent::makeHelpMsg();
1386
1387                 $astriks = str_repeat( '*** ', 14 );
1388                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
1389
1390                 foreach ( $this->mModuleMgr->getNames( 'action' ) as $name ) {
1391                         $module = $this->mModuleMgr->getModule( $name );
1392                         $msg .= self::makeHelpMsgHeader( $module, 'action' );
1393
1394                         $msg2 = $module->makeHelpMsg();
1395                         if ( $msg2 !== false ) {
1396                                 $msg .= $msg2;
1397                         }
1398                         $msg .= "\n";
1399                 }
1400
1401                 $msg .= "\n$astriks Permissions $astriks\n\n";
1402                 foreach ( self::$mRights as $right => $rightMsg ) {
1403                         $rightsMsg = $this->msg( $rightMsg['msg'], $rightMsg['params'] )
1404                                 ->useDatabase( false )
1405                                 ->inLanguage( 'en' )
1406                                 ->text();
1407                         $groups = User::getGroupsWithPermission( $right );
1408                         $msg .= "* " . $right . " *\n  $rightsMsg" .
1409                                 "\nGranted to:\n  " . str_replace( '*', 'all', implode( ', ', $groups ) ) . "\n\n";
1410                 }
1411
1412                 $msg .= "\n$astriks Formats  $astriks\n\n";
1413                 foreach ( $this->mModuleMgr->getNames( 'format' ) as $name ) {
1414                         $module = $this->mModuleMgr->getModule( $name );
1415                         $msg .= self::makeHelpMsgHeader( $module, 'format' );
1416                         $msg2 = $module->makeHelpMsg();
1417                         if ( $msg2 !== false ) {
1418                                 $msg .= $msg2;
1419                         }
1420                         $msg .= "\n";
1421                 }
1422
1423                 $credits = $this->msg( 'api-credits' )->useDatabase( 'false' )->inLanguage( 'en' )->text();
1424                 $credits = str_replace( "\n", "\n   ", $credits );
1425                 $msg .= "\n*** Credits: ***\n   $credits\n";
1426
1427                 return $msg;
1428         }
1429
1430         /**
1431          * @deprecated since 1.25
1432          * @param ApiBase $module
1433          * @param string $paramName What type of request is this? e.g. action,
1434          *    query, list, prop, meta, format
1435          * @return string
1436          */
1437         public static function makeHelpMsgHeader( $module, $paramName ) {
1438                 wfDeprecated( __METHOD__, '1.25' );
1439                 $modulePrefix = $module->getModulePrefix();
1440                 if ( strval( $modulePrefix ) !== '' ) {
1441                         $modulePrefix = "($modulePrefix) ";
1442                 }
1443
1444                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
1445         }
1446
1447         /**
1448          * Check whether the user wants us to show version information in the API help
1449          * @return bool
1450          * @deprecated since 1.21, always returns false
1451          */
1452         public function getShowVersions() {
1453                 wfDeprecated( __METHOD__, '1.21' );
1454
1455                 return false;
1456         }
1457
1458         /**
1459          * Add or overwrite a module in this ApiMain instance. Intended for use by extending
1460          * classes who wish to add their own modules to their lexicon or override the
1461          * behavior of inherent ones.
1462          *
1463          * @deprecated since 1.21, Use getModuleManager()->addModule() instead.
1464          * @param string $name The identifier for this module.
1465          * @param ApiBase $class The class where this module is implemented.
1466          */
1467         protected function addModule( $name, $class ) {
1468                 $this->getModuleManager()->addModule( $name, 'action', $class );
1469         }
1470
1471         /**
1472          * Add or overwrite an output format for this ApiMain. Intended for use by extending
1473          * classes who wish to add to or modify current formatters.
1474          *
1475          * @deprecated since 1.21, Use getModuleManager()->addModule() instead.
1476          * @param string $name The identifier for this format.
1477          * @param ApiFormatBase $class The class implementing this format.
1478          */
1479         protected function addFormat( $name, $class ) {
1480                 $this->getModuleManager()->addModule( $name, 'format', $class );
1481         }
1482
1483         /**
1484          * Get the array mapping module names to class names
1485          * @deprecated since 1.21, Use getModuleManager()'s methods instead.
1486          * @return array
1487          */
1488         function getModules() {
1489                 return $this->getModuleManager()->getNamesWithClasses( 'action' );
1490         }
1491
1492         /**
1493          * Returns the list of supported formats in form ( 'format' => 'ClassName' )
1494          *
1495          * @since 1.18
1496          * @deprecated since 1.21, Use getModuleManager()'s methods instead.
1497          * @return array
1498          */
1499         public function getFormats() {
1500                 return $this->getModuleManager()->getNamesWithClasses( 'format' );
1501         }
1502
1503         /**@}*/
1504
1505 }
1506
1507 /**
1508  * This exception will be thrown when dieUsage is called to stop module execution.
1509  *
1510  * @ingroup API
1511  */
1512 class UsageException extends MWException {
1513
1514         private $mCodestr;
1515
1516         /**
1517          * @var null|array
1518          */
1519         private $mExtraData;
1520
1521         /**
1522          * @param string $message
1523          * @param string $codestr
1524          * @param int $code
1525          * @param array|null $extradata
1526          */
1527         public function __construct( $message, $codestr, $code = 0, $extradata = null ) {
1528                 parent::__construct( $message, $code );
1529                 $this->mCodestr = $codestr;
1530                 $this->mExtraData = $extradata;
1531         }
1532
1533         /**
1534          * @return string
1535          */
1536         public function getCodeString() {
1537                 return $this->mCodestr;
1538         }
1539
1540         /**
1541          * @return array
1542          */
1543         public function getMessageArray() {
1544                 $result = array(
1545                         'code' => $this->mCodestr,
1546                         'info' => $this->getMessage()
1547                 );
1548                 if ( is_array( $this->mExtraData ) ) {
1549                         $result = array_merge( $result, $this->mExtraData );
1550                 }
1551
1552                 return $result;
1553         }
1554
1555         /**
1556          * @return string
1557          */
1558         public function __toString() {
1559                 return "{$this->getCodeString()}: {$this->getMessage()}";
1560         }
1561 }
1562
1563 /**
1564  * For really cool vim folding this needs to be at the end:
1565  * vim: foldmarker=@{,@} foldmethod=marker
1566  */