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         /**
  44          * When no format parameter is given, this format will be used
  45          */
  46         const API_DEFAULT_FORMAT = 'xmlfm';
  47
  48         /**
  49          * List of available modules: action name => module class
  50          */
  51         private static $Modules = array(
  52                 'login' => 'ApiLogin',
  53                 'logout' => 'ApiLogout',
  54                 'createaccount' => 'ApiCreateAccount',
  55                 'query' => 'ApiQuery',
  56                 'expandtemplates' => 'ApiExpandTemplates',
  57                 'parse' => 'ApiParse',
  58                 'opensearch' => 'ApiOpenSearch',
  59                 'feedcontributions' => 'ApiFeedContributions',
  60                 'feedwatchlist' => 'ApiFeedWatchlist',
  61                 'help' => 'ApiHelp',
  62                 'paraminfo' => 'ApiParamInfo',
  63                 'rsd' => 'ApiRsd',
  64                 'compare' => 'ApiComparePages',
  65                 'tokens' => 'ApiTokens',
  66
  67                 // Write modules
  68                 'purge' => 'ApiPurge',
  69                 'setnotificationtimestamp' => 'ApiSetNotificationTimestamp',
  70                 'rollback' => 'ApiRollback',
  71                 'delete' => 'ApiDelete',
  72                 'undelete' => 'ApiUndelete',
  73                 'protect' => 'ApiProtect',
  74                 'block' => 'ApiBlock',
  75                 'unblock' => 'ApiUnblock',
  76                 'move' => 'ApiMove',
  77                 'edit' => 'ApiEditPage',
  78                 'upload' => 'ApiUpload',
  79                 'filerevert' => 'ApiFileRevert',
  80                 'emailuser' => 'ApiEmailUser',
  81                 'watch' => 'ApiWatch',
  82                 'patrol' => 'ApiPatrol',
  83                 'import' => 'ApiImport',
  84                 'userrights' => 'ApiUserrights',
  85                 'options' => 'ApiOptions',
  86                 'imagerotate' => 'ApiImageRotate',
  87         );
  88
  89         /**
  90          * List of available formats: format name => format class
  91          */
  92         private static $Formats = array(
  93                 'json' => 'ApiFormatJson',
  94                 'jsonfm' => 'ApiFormatJson',
  95                 'php' => 'ApiFormatPhp',
  96                 'phpfm' => 'ApiFormatPhp',
  97                 'wddx' => 'ApiFormatWddx',
  98                 'wddxfm' => 'ApiFormatWddx',
  99                 'xml' => 'ApiFormatXml',
 100                 'xmlfm' => 'ApiFormatXml',
 101                 'yaml' => 'ApiFormatYaml',
 102                 'yamlfm' => 'ApiFormatYaml',
 103                 'rawfm' => 'ApiFormatJson',
 104                 'txt' => 'ApiFormatTxt',
 105                 'txtfm' => 'ApiFormatTxt',
 106                 'dbg' => 'ApiFormatDbg',
 107                 'dbgfm' => 'ApiFormatDbg',
 108                 'dump' => 'ApiFormatDump',
 109                 'dumpfm' => 'ApiFormatDump',
 110                 'none' => 'ApiFormatNone',
 111         );
 112
 113         // @codingStandardsIgnoreStart String contenation on "msg" not allowed to break long line
 114         /**
 115          * List of user roles that are specifically relevant to the API.
 116          * array( 'right' => array ( 'msg'    => 'Some message with a $1',
 117          *                           'params' => array ( $someVarToSubst ) ),
 118          *                          );
 119          */
 120         private static $mRights = array(
 121                 'writeapi' => array(
 122                         'msg' => 'Use of the write API',
 123                         'params' => array()
 124                 ),
 125                 'apihighlimits' => array(
 126                         'msg' => 'Use higher limits in API queries (Slow queries: $1 results; Fast queries: $2 results). The limits for slow queries also apply to multivalue parameters.',
 127                         'params' => array( ApiBase::LIMIT_SML2, ApiBase::LIMIT_BIG2 )
 128                 )
 129         );
 130         // @codingStandardsIgnoreEnd
 131
 132         /**
 133          * @var ApiFormatBase
 134          */
 135         private $mPrinter;
 136
 137         private $mModuleMgr, $mResult;
 138         private $mAction;
 139         private $mEnableWrite;
 140         private $mInternalMode, $mSquidMaxage, $mModule;
 141
 142         private $mCacheMode = 'private';
 143         private $mCacheControl = array();
 144         private $mParamsUsed = array();
 145
 146         /**
 147          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 148          *
 149          * @param $context IContextSource|WebRequest - if this is an instance of
 150          *    FauxRequest, errors are thrown and no printing occurs
 151          * @param bool $enableWrite should be set to true if the api may modify data
 152          */
 153         public function __construct( $context = null, $enableWrite = false ) {
 154                 if ( $context === null ) {
 155                         $context = RequestContext::getMain();
 156                 } elseif ( $context instanceof WebRequest ) {
 157                         // BC for pre-1.19
 158                         $request = $context;
 159                         $context = RequestContext::getMain();
 160                 }
 161                 // We set a derivative context so we can change stuff later
 162                 $this->setContext( new DerivativeContext( $context ) );
 163
 164                 if ( isset( $request ) ) {
 165                         $this->getContext()->setRequest( $request );
 166                 }
 167
 168                 $this->mInternalMode = ( $this->getRequest() instanceof FauxRequest );
 169
 170                 // Special handling for the main module: $parent === $this
 171                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 172
 173                 if ( !$this->mInternalMode ) {
 174                         // Impose module restrictions.
 175                         // If the current user cannot read,
 176                         // Remove all modules other than login
 177                         global $wgUser;
 178
 179                         if ( $this->getVal( 'callback' ) !== null ) {
 180                                 // JSON callback allows cross-site reads.
 181                                 // For safety, strip user credentials.
 182                                 wfDebug( "API: stripping user credentials for JSON callback\n" );
 183                                 $wgUser = new User();
 184                                 $this->getContext()->setUser( $wgUser );
 185                         }
 186                 }
 187
 188                 global $wgAPIModules, $wgAPIFormatModules;
 189                 $this->mModuleMgr = new ApiModuleManager( $this );
 190                 $this->mModuleMgr->addModules( self::$Modules, 'action' );
 191                 $this->mModuleMgr->addModules( $wgAPIModules, 'action' );
 192                 $this->mModuleMgr->addModules( self::$Formats, 'format' );
 193                 $this->mModuleMgr->addModules( $wgAPIFormatModules, 'format' );
 194
 195                 $this->mResult = new ApiResult( $this );
 196                 $this->mEnableWrite = $enableWrite;
 197
 198                 $this->mSquidMaxage = -1; // flag for executeActionWithErrorHandling()
 199                 $this->mCommit = false;
 200         }
 201
 202         /**
 203          * Return true if the API was started by other PHP code using FauxRequest
 204          * @return bool
 205          */
 206         public function isInternalMode() {
 207                 return $this->mInternalMode;
 208         }
 209
 210         /**
 211          * Get the ApiResult object associated with current request
 212          *
 213          * @return ApiResult
 214          */
 215         public function getResult() {
 216                 return $this->mResult;
 217         }
 218
 219         /**
 220          * Get the API module object. Only works after executeAction()
 221          *
 222          * @return ApiBase
 223          */
 224         public function getModule() {
 225                 return $this->mModule;
 226         }
 227
 228         /**
 229          * Get the result formatter object. Only works after setupExecuteAction()
 230          *
 231          * @return ApiFormatBase
 232          */
 233         public function getPrinter() {
 234                 return $this->mPrinter;
 235         }
 236
 237         /**
 238          * Set how long the response should be cached.
 239          *
 240          * @param $maxage
 241          */
 242         public function setCacheMaxAge( $maxage ) {
 243                 $this->setCacheControl( array(
 244                         'max-age' => $maxage,
 245                         's-maxage' => $maxage
 246                 ) );
 247         }
 248
 249         /**
 250          * Set the type of caching headers which will be sent.
 251          *
 252          * @param string $mode One of:
 253          *    - 'public':     Cache this object in public caches, if the maxage or smaxage
 254          *         parameter is set, or if setCacheMaxAge() was called. If a maximum age is
 255          *         not provided by any of these means, the object will be private.
 256          *    - 'private':    Cache this object only in private client-side caches.
 257          *    - 'anon-public-user-private': Make this object cacheable for logged-out
 258          *         users, but private for logged-in users. IMPORTANT: If this is set, it must be
 259          *         set consistently for a given URL, it cannot be set differently depending on
 260          *         things like the contents of the database, or whether the user is logged in.
 261          *
 262          *  If the wiki does not allow anonymous users to read it, the mode set here
 263          *  will be ignored, and private caching headers will always be sent. In other words,
 264          *  the "public" mode is equivalent to saying that the data sent is as public as a page
 265          *  view.
 266          *
 267          *  For user-dependent data, the private mode should generally be used. The
 268          *  anon-public-user-private mode should only be used where there is a particularly
 269          *  good performance reason for caching the anonymous response, but where the
 270          *  response to logged-in users may differ, or may contain private data.
 271          *
 272          *  If this function is never called, then the default will be the private mode.
 273          */
 274         public function setCacheMode( $mode ) {
 275                 if ( !in_array( $mode, array( 'private', 'public', 'anon-public-user-private' ) ) ) {
 276                         wfDebug( __METHOD__ . ": unrecognised cache mode \"$mode\"\n" );
 277
 278                         // Ignore for forwards-compatibility
 279                         return;
 280                 }
 281
 282                 if ( !User::isEveryoneAllowed( 'read' ) ) {
 283                         // Private wiki, only private headers
 284                         if ( $mode !== 'private' ) {
 285                                 wfDebug( __METHOD__ . ": ignoring request for $mode cache mode, private wiki\n" );
 286
 287                                 return;
 288                         }
 289                 }
 290
 291                 wfDebug( __METHOD__ . ": setting cache mode $mode\n" );
 292                 $this->mCacheMode = $mode;
 293         }
 294
 295         /**
 296          * @deprecated since 1.17 Private caching is now the default, so there is usually no
 297          * need to call this function. If there is a need, you can use
 298          * $this->setCacheMode('private')
 299          */
 300         public function setCachePrivate() {
 301                 wfDeprecated( __METHOD__, '1.17' );
 302                 $this->setCacheMode( 'private' );
 303         }
 304
 305         /**
 306          * Set directives (key/value pairs) for the Cache-Control header.
 307          * Boolean values will be formatted as such, by including or omitting
 308          * without an equals sign.
 309          *
 310          * Cache control values set here will only be used if the cache mode is not
 311          * private, see setCacheMode().
 312          *
 313          * @param $directives array
 314          */
 315         public function setCacheControl( $directives ) {
 316                 $this->mCacheControl = $directives + $this->mCacheControl;
 317         }
 318
 319         /**
 320          * Make sure Vary: Cookie and friends are set. Use this when the output of a request
 321          * may be cached for anons but may not be cached for logged-in users.
 322          *
 323          * WARNING: This function must be called CONSISTENTLY for a given URL. This means that a
 324          * given URL must either always or never call this function; if it sometimes does and
 325          * sometimes doesn't, stuff will break.
 326          *
 327          * @deprecated since 1.17 Use setCacheMode( 'anon-public-user-private' )
 328          */
 329         public function setVaryCookie() {
 330                 wfDeprecated( __METHOD__, '1.17' );
 331                 $this->setCacheMode( 'anon-public-user-private' );
 332         }
 333
 334         /**
 335          * Create an instance of an output formatter by its name
 336          *
 337          * @param $format string
 338          *
 339          * @return ApiFormatBase
 340          */
 341         public function createPrinterByName( $format ) {
 342                 $printer = $this->mModuleMgr->getModule( $format, 'format' );
 343                 if ( $printer === null ) {
 344                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 345                 }
 346
 347                 return $printer;
 348         }
 349
 350         /**
 351          * Execute api request. Any errors will be handled if the API was called by the remote client.
 352          */
 353         public function execute() {
 354                 $this->profileIn();
 355                 if ( $this->mInternalMode ) {
 356                         $this->executeAction();
 357                 } else {
 358                         $this->executeActionWithErrorHandling();
 359                 }
 360
 361                 $this->profileOut();
 362         }
 363
 364         /**
 365          * Execute an action, and in case of an error, erase whatever partial results
 366          * have been accumulated, and replace it with an error message and a help screen.
 367          */
 368         protected function executeActionWithErrorHandling() {
 369                 // Verify the CORS header before executing the action
 370                 if ( !$this->handleCORS() ) {
 371                         // handleCORS() has sent a 403, abort
 372                         return;
 373                 }
 374
 375                 // Exit here if the request method was OPTIONS
 376                 // (assume there will be a followup GET or POST)
 377                 if ( $this->getRequest()->getMethod() === 'OPTIONS' ) {
 378                         return;
 379                 }
 380
 381                 // In case an error occurs during data output,
 382                 // clear the output buffer and print just the error information
 383                 ob_start();
 384
 385                 $t = microtime( true );
 386                 try {
 387                         $this->executeAction();
 388                 } catch ( Exception $e ) {
 389                         // Allow extra cleanup and logging
 390                         wfRunHooks( 'ApiMain::onException', array( $this, $e ) );
 391
 392                         // Log it
 393                         if ( !( $e instanceof UsageException ) ) {
 394                                 MWExceptionHandler::logException( $e );
 395                         }
 396
 397                         // Handle any kind of exception by outputting properly formatted error message.
 398                         // If this fails, an unhandled exception should be thrown so that global error
 399                         // handler will process and log it.
 400
 401                         $errCode = $this->substituteResultWithError( $e );
 402
 403                         // Error results should not be cached
 404                         $this->setCacheMode( 'private' );
 405
 406                         $response = $this->getRequest()->response();
 407                         $headerStr = 'MediaWiki-API-Error: ' . $errCode;
 408                         if ( $e->getCode() === 0 ) {
 409                                 $response->header( $headerStr );
 410                         } else {
 411                                 $response->header( $headerStr, true, $e->getCode() );
 412                         }
 413
 414                         // Reset and print just the error message
 415                         ob_clean();
 416
 417                         // If the error occurred during printing, do a printer->profileOut()
 418                         $this->mPrinter->safeProfileOut();
 419                         $this->printResult( true );
 420                 }
 421
 422                 // Log the request whether or not there was an error
 423                 $this->logRequest( microtime( true ) - $t );
 424
 425                 // Send cache headers after any code which might generate an error, to
 426                 // avoid sending public cache headers for errors.
 427                 $this->sendCacheHeaders();
 428
 429                 if ( $this->mPrinter->getIsHtml() && !$this->mPrinter->isDisabled() ) {
 430                         echo wfReportTime();
 431                 }
 432
 433                 ob_end_flush();
 434         }
 435
 436         /**
 437          * Check the &origin= query parameter against the Origin: HTTP header and respond appropriately.
 438          *
 439          * If no origin parameter is present, nothing happens.
 440          * If an origin parameter is present but doesn't match the Origin header, a 403 status code
 441          * is set and false is returned.
 442          * If the parameter and the header do match, the header is checked against $wgCrossSiteAJAXdomains
 443          * and $wgCrossSiteAJAXdomainExceptions, and if the origin qualifies, the appropriate CORS
 444          * headers are set.
 445          *
 446          * @return bool False if the caller should abort (403 case), true otherwise (all other cases)
 447          */
 448         protected function handleCORS() {
 449                 global $wgCrossSiteAJAXdomains, $wgCrossSiteAJAXdomainExceptions;
 450
 451                 $originParam = $this->getParameter( 'origin' ); // defaults to null
 452                 if ( $originParam === null ) {
 453                         // No origin parameter, nothing to do
 454                         return true;
 455                 }
 456
 457                 $request = $this->getRequest();
 458                 $response = $request->response();
 459                 // Origin: header is a space-separated list of origins, check all of them
 460                 $originHeader = $request->getHeader( 'Origin' );
 461                 if ( $originHeader === false ) {
 462                         $origins = array();
 463                 } else {
 464                         $origins = explode( ' ', $originHeader );
 465                 }
 466
 467                 if ( !in_array( $originParam, $origins ) ) {
 468                         // origin parameter set but incorrect
 469                         // Send a 403 response
 470                         $message = HttpStatus::getMessage( 403 );
 471                         $response->header( "HTTP/1.1 403 $message", true, 403 );
 472                         $response->header( 'Cache-Control: no-cache' );
 473                         echo "'origin' parameter does not match Origin header\n";
 474
 475                         return false;
 476                 }
 477
 478                 $matchOrigin = self::matchOrigin(
 479                         $originParam,
 480                         $wgCrossSiteAJAXdomains,
 481                         $wgCrossSiteAJAXdomainExceptions
 482                 );
 483
 484                 if ( $matchOrigin ) {
 485                         $response->header( "Access-Control-Allow-Origin: $originParam" );
 486                         $response->header( 'Access-Control-Allow-Credentials: true' );
 487                         $this->getOutput()->addVaryHeader( 'Origin' );
 488                 }
 489
 490                 return true;
 491         }
 492
 493         /**
 494          * Attempt to match an Origin header against a set of rules and a set of exceptions
 495          * @param string $value Origin header
 496          * @param array $rules Set of wildcard rules
 497          * @param array $exceptions Set of wildcard rules
 498          * @return bool True if $value matches a rule in $rules and doesn't match
 499          *    any rules in $exceptions, false otherwise
 500          */
 501         protected static function matchOrigin( $value, $rules, $exceptions ) {
 502                 foreach ( $rules as $rule ) {
 503                         if ( preg_match( self::wildcardToRegex( $rule ), $value ) ) {
 504                                 // Rule matches, check exceptions
 505                                 foreach ( $exceptions as $exc ) {
 506                                         if ( preg_match( self::wildcardToRegex( $exc ), $value ) ) {
 507                                                 return false;
 508                                         }
 509                                 }
 510
 511                                 return true;
 512                         }
 513                 }
 514
 515                 return false;
 516         }
 517
 518         /**
 519          * Helper function to convert wildcard string into a regex
 520          * '*' => '.*?'
 521          * '?' => '.'
 522          *
 523          * @param string $wildcard String with wildcards
 524          * @return string Regular expression
 525          */
 526         protected static function wildcardToRegex( $wildcard ) {
 527                 $wildcard = preg_quote( $wildcard, '/' );
 528                 $wildcard = str_replace(
 529                         array( '\*', '\?' ),
 530                         array( '.*?', '.' ),
 531                         $wildcard
 532                 );
 533
 534                 return "/https?:\/\/$wildcard/";
 535         }
 536
 537         protected function sendCacheHeaders() {
 538                 global $wgUseXVO, $wgVaryOnXFP;
 539                 $response = $this->getRequest()->response();
 540                 $out = $this->getOutput();
 541
 542                 if ( $wgVaryOnXFP ) {
 543                         $out->addVaryHeader( 'X-Forwarded-Proto' );
 544                 }
 545
 546                 if ( $this->mCacheMode == 'private' ) {
 547                         $response->header( 'Cache-Control: private' );
 548
 549                         return;
 550                 }
 551
 552                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 553                         $out->addVaryHeader( 'Cookie' );
 554                         $response->header( $out->getVaryHeader() );
 555                         if ( $wgUseXVO ) {
 556                                 $response->header( $out->getXVO() );
 557                                 if ( $out->haveCacheVaryCookies() ) {
 558                                         // Logged in, mark this request private
 559                                         $response->header( 'Cache-Control: private' );
 560
 561                                         return;
 562                                 }
 563                                 // Logged out, send normal public headers below
 564                         } elseif ( session_id() != '' ) {
 565                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 566                                 // Mark request private
 567                                 $response->header( 'Cache-Control: private' );
 568
 569                                 return;
 570                         } // else no XVO and anonymous, send public headers below
 571                 }
 572
 573                 // Send public headers
 574                 $response->header( $out->getVaryHeader() );
 575                 if ( $wgUseXVO ) {
 576                         $response->header( $out->getXVO() );
 577                 }
 578
 579                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 580                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 581                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 582                 }
 583                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 584                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 585                 }
 586
 587                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 588                         // Public cache not requested
 589                         // Sending a Vary header in this case is harmless, and protects us
 590                         // against conditional calls of setCacheMaxAge().
 591                         $response->header( 'Cache-Control: private' );
 592
 593                         return;
 594                 }
 595
 596                 $this->mCacheControl['public'] = true;
 597
 598                 // Send an Expires header
 599                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 600                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 601                 $response->header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 602
 603                 // Construct the Cache-Control header
 604                 $ccHeader = '';
 605                 $separator = '';
 606                 foreach ( $this->mCacheControl as $name => $value ) {
 607                         if ( is_bool( $value ) ) {
 608                                 if ( $value ) {
 609                                         $ccHeader .= $separator . $name;
 610                                         $separator = ', ';
 611                                 }
 612                         } else {
 613                                 $ccHeader .= $separator . "$name=$value";
 614                                 $separator = ', ';
 615                         }
 616                 }
 617
 618                 $response->header( "Cache-Control: $ccHeader" );
 619         }
 620
 621         /**
 622          * Replace the result data with the information about an exception.
 623          * Returns the error code
 624          * @param $e Exception
 625          * @return string
 626          */
 627         protected function substituteResultWithError( $e ) {
 628                 global $wgShowHostnames;
 629
 630                 $result = $this->getResult();
 631                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 632                 if ( !isset( $this->mPrinter ) ) {
 633                         // The printer has not been created yet. Try to manually get formatter value.
 634                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 635                         if ( !$this->mModuleMgr->isDefined( $value, 'format' ) ) {
 636                                 $value = self::API_DEFAULT_FORMAT;
 637                         }
 638
 639                         $this->mPrinter = $this->createPrinterByName( $value );
 640                         if ( $this->mPrinter->getNeedsRawData() ) {
 641                                 $result->setRawMode();
 642                         }
 643                 }
 644
 645                 if ( $e instanceof UsageException ) {
 646                         // User entered incorrect parameters - print usage screen
 647                         $errMessage = $e->getMessageArray();
 648
 649                         // Only print the help message when this is for the developer, not runtime
 650                         if ( $this->mPrinter->getWantsHelp() || $this->mAction == 'help' ) {
 651                                 ApiResult::setContent( $errMessage, $this->makeHelpMsg() );
 652                         }
 653                 } else {
 654                         global $wgShowSQLErrors, $wgShowExceptionDetails;
 655                         // Something is seriously wrong
 656                         if ( ( $e instanceof DBQueryError ) && !$wgShowSQLErrors ) {
 657                                 $info = 'Database query error';
 658                         } else {
 659                                 $info = "Exception Caught: {$e->getMessage()}";
 660                         }
 661
 662                         $errMessage = array(
 663                                 'code' => 'internal_api_error_' . get_class( $e ),
 664                                 'info' => $info,
 665                         );
 666                         ApiResult::setContent(
 667                                 $errMessage,
 668                                 $wgShowExceptionDetails ? "\n\n{$e->getTraceAsString()}\n\n" : ''
 669                         );
 670                 }
 671
 672                 // Remember all the warnings to re-add them later
 673                 $oldResult = $result->getData();
 674                 $warnings = isset( $oldResult['warnings'] ) ? $oldResult['warnings'] : null;
 675
 676                 $result->reset();
 677                 $result->disableSizeCheck();
 678                 // Re-add the id
 679                 $requestid = $this->getParameter( 'requestid' );
 680                 if ( !is_null( $requestid ) ) {
 681                         $result->addValue( null, 'requestid', $requestid );
 682                 }
 683                 if ( $wgShowHostnames ) {
 684                         // servedby is especially useful when debugging errors
 685                         $result->addValue( null, 'servedby', wfHostName() );
 686                 }
 687                 if ( $warnings !== null ) {
 688                         $result->addValue( null, 'warnings', $warnings );
 689                 }
 690
 691                 $result->addValue( null, 'error', $errMessage );
 692
 693                 return $errMessage['code'];
 694         }
 695
 696         /**
 697          * Set up for the execution.
 698          * @return array
 699          */
 700         protected function setupExecuteAction() {
 701                 global $wgShowHostnames;
 702
 703                 // First add the id to the top element
 704                 $result = $this->getResult();
 705                 $requestid = $this->getParameter( 'requestid' );
 706                 if ( !is_null( $requestid ) ) {
 707                         $result->addValue( null, 'requestid', $requestid );
 708                 }
 709
 710                 if ( $wgShowHostnames ) {
 711                         $servedby = $this->getParameter( 'servedby' );
 712                         if ( $servedby ) {
 713                                 $result->addValue( null, 'servedby', wfHostName() );
 714                         }
 715                 }
 716
 717                 $params = $this->extractRequestParams();
 718
 719                 $this->mAction = $params['action'];
 720
 721                 if ( !is_string( $this->mAction ) ) {
 722                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 723                 }
 724
 725                 return $params;
 726         }
 727
 728         /**
 729          * Set up the module for response
 730          * @return ApiBase The module that will handle this action
 731          */
 732         protected function setupModule() {
 733                 // Instantiate the module requested by the user
 734                 $module = $this->mModuleMgr->getModule( $this->mAction, 'action' );
 735                 if ( $module === null ) {
 736                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 737                 }
 738                 $moduleParams = $module->extractRequestParams();
 739
 740                 // Die if token required, but not provided
 741                 $salt = $module->getTokenSalt();
 742                 if ( $salt !== false ) {
 743                         if ( !isset( $moduleParams['token'] ) ) {
 744                                 $this->dieUsageMsg( array( 'missingparam', 'token' ) );
 745                         }
 746
 747                         if ( !$this->getUser()->matchEditToken(
 748                                 $moduleParams['token'],
 749                                 $salt,
 750                                 $this->getContext()->getRequest() )
 751                         ) {
 752                                 $this->dieUsageMsg( 'sessionfailure' );
 753                         }
 754                 }
 755
 756                 return $module;
 757         }
 758
 759         /**
 760          * Check the max lag if necessary
 761          * @param $module ApiBase object: Api module being used
 762          * @param array $params an array containing the request parameters.
 763          * @return boolean True on success, false should exit immediately
 764          */
 765         protected function checkMaxLag( $module, $params ) {
 766                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
 767                         // Check for maxlag
 768                         global $wgShowHostnames;
 769                         $maxLag = $params['maxlag'];
 770                         list( $host, $lag ) = wfGetLB()->getMaxLag();
 771                         if ( $lag > $maxLag ) {
 772                                 $response = $this->getRequest()->response();
 773
 774                                 $response->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
 775                                 $response->header( 'X-Database-Lag: ' . intval( $lag ) );
 776
 777                                 if ( $wgShowHostnames ) {
 778                                         $this->dieUsage( "Waiting for $host: $lag seconds lagged", 'maxlag' );
 779                                 }
 780
 781                                 $this->dieUsage( "Waiting for a database server: $lag seconds lagged", 'maxlag' );
 782                         }
 783                 }
 784
 785                 return true;
 786         }
 787
 788         /**
 789          * Check for sufficient permissions to execute
 790          * @param $module ApiBase An Api module
 791          */
 792         protected function checkExecutePermissions( $module ) {
 793                 $user = $this->getUser();
 794                 if ( $module->isReadMode() && !User::isEveryoneAllowed( 'read' ) &&
 795                         !$user->isAllowed( 'read' )
 796                 ) {
 797                         $this->dieUsageMsg( 'readrequired' );
 798                 }
 799                 if ( $module->isWriteMode() ) {
 800                         if ( !$this->mEnableWrite ) {
 801                                 $this->dieUsageMsg( 'writedisabled' );
 802                         }
 803                         if ( !$user->isAllowed( 'writeapi' ) ) {
 804                                 $this->dieUsageMsg( 'writerequired' );
 805                         }
 806                         if ( wfReadOnly() ) {
 807                                 $this->dieReadOnly();
 808                         }
 809                 }
 810
 811                 // Allow extensions to stop execution for arbitrary reasons.
 812                 $message = false;
 813                 if ( !wfRunHooks( 'ApiCheckCanExecute', array( $module, $user, &$message ) ) ) {
 814                         $this->dieUsageMsg( $message );
 815                 }
 816         }
 817
 818         /**
 819          * Check POST for external response and setup result printer
 820          * @param $module ApiBase An Api module
 821          * @param array $params an array with the request parameters
 822          */
 823         protected function setupExternalResponse( $module, $params ) {
 824                 if ( !$this->getRequest()->wasPosted() && $module->mustBePosted() ) {
 825                         // Module requires POST. GET request might still be allowed
 826                         // if $wgDebugApi is true, otherwise fail.
 827                         $this->dieUsageMsgOrDebug( array( 'mustbeposted', $this->mAction ) );
 828                 }
 829
 830                 // See if custom printer is used
 831                 $this->mPrinter = $module->getCustomPrinter();
 832                 if ( is_null( $this->mPrinter ) ) {
 833                         // Create an appropriate printer
 834                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
 835                 }
 836
 837                 if ( $this->mPrinter->getNeedsRawData() ) {
 838                         $this->getResult()->setRawMode();
 839                 }
 840         }
 841
 842         /**
 843          * Execute the actual module, without any error handling
 844          */
 845         protected function executeAction() {
 846                 $params = $this->setupExecuteAction();
 847                 $module = $this->setupModule();
 848                 $this->mModule = $module;
 849
 850                 $this->checkExecutePermissions( $module );
 851
 852                 if ( !$this->checkMaxLag( $module, $params ) ) {
 853                         return;
 854                 }
 855
 856                 if ( !$this->mInternalMode ) {
 857                         $this->setupExternalResponse( $module, $params );
 858                 }
 859
 860                 // Execute
 861                 $module->profileIn();
 862                 $module->execute();
 863                 wfRunHooks( 'APIAfterExecute', array( &$module ) );
 864                 $module->profileOut();
 865
 866                 $this->reportUnusedParams();
 867
 868                 if ( !$this->mInternalMode ) {
 869                         //append Debug information
 870                         MWDebug::appendDebugInfoToApiResult( $this->getContext(), $this->getResult() );
 871
 872                         // Print result data
 873                         $this->printResult( false );
 874                 }
 875         }
 876
 877         /**
 878          * Log the preceding request
 879          * @param int $time Time in seconds
 880          */
 881         protected function logRequest( $time ) {
 882                 $request = $this->getRequest();
 883                 $milliseconds = $time === null ? '?' : round( $time * 1000 );
 884                 $s = 'API' .
 885                         ' ' . $request->getMethod() .
 886                         ' ' . wfUrlencode( str_replace( ' ', '_', $this->getUser()->getName() ) ) .
 887                         ' ' . $request->getIP() .
 888                         ' T=' . $milliseconds . 'ms';
 889                 foreach ( $this->getParamsUsed() as $name ) {
 890                         $value = $request->getVal( $name );
 891                         if ( $value === null ) {
 892                                 continue;
 893                         }
 894                         $s .= ' ' . $name . '=';
 895                         if ( strlen( $value ) > 256 ) {
 896                                 $encValue = $this->encodeRequestLogValue( substr( $value, 0, 256 ) );
 897                                 $s .= $encValue . '[...]';
 898                         } else {
 899                                 $s .= $this->encodeRequestLogValue( $value );
 900                         }
 901                 }
 902                 $s .= "\n";
 903                 wfDebugLog( 'api', $s, false );
 904         }
 905
 906         /**
 907          * Encode a value in a format suitable for a space-separated log line.
 908          */
 909         protected function encodeRequestLogValue( $s ) {
 910                 static $table;
 911                 if ( !$table ) {
 912                         $chars = ';@$!*(),/:';
 913                         $numChars = strlen( $chars );
 914                         for ( $i = 0; $i < $numChars; $i++ ) {
 915                                 $table[rawurlencode( $chars[$i] )] = $chars[$i];
 916                         }
 917                 }
 918
 919                 return strtr( rawurlencode( $s ), $table );
 920         }
 921
 922         /**
 923          * Get the request parameters used in the course of the preceding execute() request
 924          */
 925         protected function getParamsUsed() {
 926                 return array_keys( $this->mParamsUsed );
 927         }
 928
 929         /**
 930          * Get a request value, and register the fact that it was used, for logging.
 931          */
 932         public function getVal( $name, $default = null ) {
 933                 $this->mParamsUsed[$name] = true;
 934
 935                 return $this->getRequest()->getVal( $name, $default );
 936         }
 937
 938         /**
 939          * Get a boolean request value, and register the fact that the parameter
 940          * was used, for logging.
 941          */
 942         public function getCheck( $name ) {
 943                 $this->mParamsUsed[$name] = true;
 944
 945                 return $this->getRequest()->getCheck( $name );
 946         }
 947
 948         /**
 949          * Get a request upload, and register the fact that it was used, for logging.
 950          *
 951          * @since 1.21
 952          * @param string $name Parameter name
 953          * @return WebRequestUpload
 954          */
 955         public function getUpload( $name ) {
 956                 $this->mParamsUsed[$name] = true;
 957
 958                 return $this->getRequest()->getUpload( $name );
 959         }
 960
 961         /**
 962          * Report unused parameters, so the client gets a hint in case it gave us parameters we don't know,
 963          * for example in case of spelling mistakes or a missing 'g' prefix for generators.
 964          */
 965         protected function reportUnusedParams() {
 966                 $paramsUsed = $this->getParamsUsed();
 967                 $allParams = $this->getRequest()->getValueNames();
 968
 969                 if ( !$this->mInternalMode ) {
 970                         // Printer has not yet executed; don't warn that its parameters are unused
 971                         $printerParams = array_map(
 972                                 array( $this->mPrinter, 'encodeParamName' ),
 973                                 array_keys( $this->mPrinter->getFinalParams() ?: array() )
 974                         );
 975                         $unusedParams = array_diff( $allParams, $paramsUsed, $printerParams );
 976                 } else {
 977                         $unusedParams = array_diff( $allParams, $paramsUsed );
 978                 }
 979
 980                 if ( count( $unusedParams ) ) {
 981                         $s = count( $unusedParams ) > 1 ? 's' : '';
 982                         $this->setWarning( "Unrecognized parameter$s: '" . implode( $unusedParams, "', '" ) . "'" );
 983                 }
 984         }
 985
 986         /**
 987          * Print results using the current printer
 988          *
 989          * @param $isError bool
 990          */
 991         protected function printResult( $isError ) {
 992                 global $wgDebugAPI;
 993                 if ( $wgDebugAPI !== false ) {
 994                         $this->setWarning( 'SECURITY WARNING: $wgDebugAPI is enabled' );
 995                 }
 996
 997                 $this->getResult()->cleanUpUTF8();
 998                 $printer = $this->mPrinter;
 999                 $printer->profileIn();
1000
1001                 /**
1002                  * If the help message is requested in the default (xmlfm) format,
1003                  * tell the printer not to escape ampersands so that our links do
1004                  * not break.
1005                  */
1006                 $isHelp = $isError || $this->mAction == 'help';
1007                 $printer->setUnescapeAmps( $isHelp && $printer->getFormat() == 'XML' && $printer->getIsHtml() );
1008
1009                 $printer->initPrinter( $isHelp );
1010
1011                 $printer->execute();
1012                 $printer->closePrinter();
1013                 $printer->profileOut();
1014         }
1015
1016         /**
1017          * @return bool
1018          */
1019         public function isReadMode() {
1020                 return false;
1021         }
1022
1023         /**
1024          * See ApiBase for description.
1025          *
1026          * @return array
1027          */
1028         public function getAllowedParams() {
1029                 return array(
1030                         'format' => array(
1031                                 ApiBase::PARAM_DFLT => ApiMain::API_DEFAULT_FORMAT,
1032                                 ApiBase::PARAM_TYPE => $this->mModuleMgr->getNames( 'format' )
1033                         ),
1034                         'action' => array(
1035                                 ApiBase::PARAM_DFLT => 'help',
1036                                 ApiBase::PARAM_TYPE => $this->mModuleMgr->getNames( 'action' )
1037                         ),
1038                         'maxlag' => array(
1039                                 ApiBase::PARAM_TYPE => 'integer'
1040                         ),
1041                         'smaxage' => array(
1042                                 ApiBase::PARAM_TYPE => 'integer',
1043                                 ApiBase::PARAM_DFLT => 0
1044                         ),
1045                         'maxage' => array(
1046                                 ApiBase::PARAM_TYPE => 'integer',
1047                                 ApiBase::PARAM_DFLT => 0
1048                         ),
1049                         'requestid' => null,
1050                         'servedby' => false,
1051                         'origin' => null,
1052                 );
1053         }
1054
1055         /**
1056          * See ApiBase for description.
1057          *
1058          * @return array
1059          */
1060         public function getParamDescription() {
1061                 return array(
1062                         'format' => 'The format of the output',
1063                         'action' => 'What action you would like to perform. See below for module help',
1064                         'maxlag' => array(
1065                                 'Maximum lag can be used when MediaWiki is installed on a database replicated cluster.',
1066                                 'To save actions causing any more site replication lag, this parameter can make the client',
1067                                 'wait until the replication lag is less than the specified value.',
1068                                 'In case of a replag error, error code "maxlag" is returned, with the message like',
1069                                 '"Waiting for $host: $lag seconds lagged\n".',
1070                                 'See https://www.mediawiki.org/wiki/Manual:Maxlag_parameter for more information',
1071                         ),
1072                         'smaxage' => 'Set the s-maxage header to this many seconds. Errors are never cached',
1073                         'maxage' => 'Set the max-age header to this many seconds. Errors are never cached',
1074                         'requestid' => 'Request ID to distinguish requests. This will just be output back to you',
1075                         'servedby' => 'Include the hostname that served the request in the ' .
1076                                 'results. Unconditionally shown on error',
1077                         'origin' => array(
1078                                 'When accessing the API using a cross-domain AJAX request (CORS), set this to the',
1079                                 'originating domain. This must be included in any pre-flight request, and',
1080                                 'therefore must be part of the request URI (not the POST body). This must match',
1081                                 'one of the origins in the Origin: header exactly, so it has to be set to ',
1082                                 'something like http://en.wikipedia.org or https://meta.wikimedia.org . If this',
1083                                 'parameter does not match the Origin: header, a 403 response will be returned. If',
1084                                 'this parameter matches the Origin: header and the origin is whitelisted, an',
1085                                 'Access-Control-Allow-Origin header will be set.',
1086                         ),
1087                 );
1088         }
1089
1090         /**
1091          * See ApiBase for description.
1092          *
1093          * @return array
1094          */
1095         public function getDescription() {
1096                 return array(
1097                         '',
1098                         '',
1099                         '**********************************************************************************************',
1100                         '**                                                                                          **',
1101                         '**                This is an auto-generated MediaWiki API documentation page                **',
1102                         '**                                                                                          **',
1103                         '**                               Documentation and Examples:                                **',
1104                         '**                            https://www.mediawiki.org/wiki/API                            **',
1105                         '**                                                                                          **',
1106                         '**********************************************************************************************',
1107                         '',
1108                         'Status:                All features shown on this page should be working, but the API',
1109                         '                       is still in active development, and may change at any time.',
1110                         '                       Make sure to monitor our mailing list for any updates',
1111                         '',
1112                         'Erroneous requests:    When erroneous requests are sent to the API, a HTTP header will be sent',
1113                         '                       with the key "MediaWiki-API-Error" and then both the value of the',
1114                         '                       header and the error code sent back will be set to the same value',
1115                         '',
1116                         '                       In the case of an invalid action being passed, these will have a value',
1117                         '                       of "unknown_action"',
1118                         '',
1119                         '                       For more information see https://www.mediawiki.org' .
1120                                 '/wiki/API:Errors_and_warnings',
1121                         '',
1122                         'Documentation:         https://www.mediawiki.org/wiki/API:Main_page',
1123                         'FAQ                    https://www.mediawiki.org/wiki/API:FAQ',
1124                         'Mailing list:          https://lists.wikimedia.org/mailman/listinfo/mediawiki-api',
1125                         'Api Announcements:     https://lists.wikimedia.org/mailman/listinfo/mediawiki-api-announce',
1126                         'Bugs & Requests:       https://bugzilla.wikimedia.org/buglist.cgi?component=API&' .
1127                                 'bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&order=bugs.delta_ts',
1128                         '',
1129                         '',
1130                         '',
1131                         '',
1132                         '',
1133                 );
1134         }
1135
1136         /**
1137          * @return array
1138          */
1139         public function getPossibleErrors() {
1140                 return array_merge( parent::getPossibleErrors(), array(
1141                         array( 'readonlytext' ),
1142                         array( 'code' => 'unknown_format', 'info' => 'Unrecognized format: format' ),
1143                         array( 'code' => 'unknown_action', 'info' => 'The API requires a valid action parameter' ),
1144                         array( 'code' => 'maxlag', 'info' => 'Waiting for host: x seconds lagged' ),
1145                         array( 'code' => 'maxlag', 'info' => 'Waiting for a database server: x seconds lagged' ),
1146                 ) );
1147         }
1148
1149         /**
1150          * Returns an array of strings with credits for the API
1151          * @return array
1152          */
1153         protected function getCredits() {
1154                 return array(
1155                         'API developers:',
1156                         '    Roan Kattouw - roan . kattouw @ gmail . com (lead developer Sep 2007-2009)',
1157                         '    Victor Vasiliev - vasilvv @ gmail . com',
1158                         '    Bryan Tong Minh - bryan . tongminh @ gmail . com',
1159                         '    Sam Reed - sam @ reedyboy . net',
1160                         '    Yuri Astrakhan - yuri . astrakhan @ gmail . com (creator, lead ' .
1161                                 'developer Sep 2006-Sep 2007, 2012-present)',
1162                         '',
1163                         'Please send your comments, suggestions and questions to mediawiki-api@lists.wikimedia.org',
1164                         'or file a bug report at https://bugzilla.wikimedia.org/'
1165                 );
1166         }
1167
1168         /**
1169          * Sets whether the pretty-printer should format *bold* and $italics$
1170          *
1171          * @param $help bool
1172          */
1173         public function setHelp( $help = true ) {
1174                 $this->mPrinter->setHelp( $help );
1175         }
1176
1177         /**
1178          * Override the parent to generate help messages for all available modules.
1179          *
1180          * @return string
1181          */
1182         public function makeHelpMsg() {
1183                 global $wgMemc, $wgAPICacheHelpTimeout;
1184                 $this->setHelp();
1185                 // Get help text from cache if present
1186                 $key = wfMemcKey( 'apihelp', $this->getModuleName(),
1187                         str_replace( ' ', '_', SpecialVersion::getVersion( 'nodb' ) ) );
1188                 if ( $wgAPICacheHelpTimeout > 0 ) {
1189                         $cached = $wgMemc->get( $key );
1190                         if ( $cached ) {
1191                                 return $cached;
1192                         }
1193                 }
1194                 $retval = $this->reallyMakeHelpMsg();
1195                 if ( $wgAPICacheHelpTimeout > 0 ) {
1196                         $wgMemc->set( $key, $retval, $wgAPICacheHelpTimeout );
1197                 }
1198
1199                 return $retval;
1200         }
1201
1202         /**
1203          * @return mixed|string
1204          */
1205         public function reallyMakeHelpMsg() {
1206                 $this->setHelp();
1207
1208                 // Use parent to make default message for the main module
1209                 $msg = parent::makeHelpMsg();
1210
1211                 $astriks = str_repeat( '*** ', 14 );
1212                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
1213
1214                 foreach ( $this->mModuleMgr->getNames( 'action' ) as $name ) {
1215                         $module = $this->mModuleMgr->getModule( $name );
1216                         $msg .= self::makeHelpMsgHeader( $module, 'action' );
1217
1218                         $msg2 = $module->makeHelpMsg();
1219                         if ( $msg2 !== false ) {
1220                                 $msg .= $msg2;
1221                         }
1222                         $msg .= "\n";
1223                 }
1224
1225                 $msg .= "\n$astriks Permissions $astriks\n\n";
1226                 foreach ( self::$mRights as $right => $rightMsg ) {
1227                         $groups = User::getGroupsWithPermission( $right );
1228                         $msg .= "* " . $right . " *\n  " . wfMsgReplaceArgs( $rightMsg['msg'], $rightMsg['params'] ) .
1229                                 "\nGranted to:\n  " . str_replace( '*', 'all', implode( ', ', $groups ) ) . "\n\n";
1230                 }
1231
1232                 $msg .= "\n$astriks Formats  $astriks\n\n";
1233                 foreach ( $this->mModuleMgr->getNames( 'format' ) as $name ) {
1234                         $module = $this->mModuleMgr->getModule( $name );
1235                         $msg .= self::makeHelpMsgHeader( $module, 'format' );
1236                         $msg2 = $module->makeHelpMsg();
1237                         if ( $msg2 !== false ) {
1238                                 $msg .= $msg2;
1239                         }
1240                         $msg .= "\n";
1241                 }
1242
1243                 $msg .= "\n*** Credits: ***\n   " . implode( "\n   ", $this->getCredits() ) . "\n";
1244
1245                 return $msg;
1246         }
1247
1248         /**
1249          * @param $module ApiBase
1250          * @param string $paramName What type of request is this? e.g. action,
1251          *    query, list, prop, meta, format
1252          * @return string
1253          */
1254         public static function makeHelpMsgHeader( $module, $paramName ) {
1255                 $modulePrefix = $module->getModulePrefix();
1256                 if ( strval( $modulePrefix ) !== '' ) {
1257                         $modulePrefix = "($modulePrefix) ";
1258                 }
1259
1260                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
1261         }
1262
1263         private $mCanApiHighLimits = null;
1264
1265         /**
1266          * Check whether the current user is allowed to use high limits
1267          * @return bool
1268          */
1269         public function canApiHighLimits() {
1270                 if ( !isset( $this->mCanApiHighLimits ) ) {
1271                         $this->mCanApiHighLimits = $this->getUser()->isAllowed( 'apihighlimits' );
1272                 }
1273
1274                 return $this->mCanApiHighLimits;
1275         }
1276
1277         /**
1278          * Check whether the user wants us to show version information in the API help
1279          * @return bool
1280          * @deprecated since 1.21, always returns false
1281          */
1282         public function getShowVersions() {
1283                 wfDeprecated( __METHOD__, '1.21' );
1284
1285                 return false;
1286         }
1287
1288         /**
1289          * Overrides to return this instance's module manager.
1290          * @return ApiModuleManager
1291          */
1292         public function getModuleManager() {
1293                 return $this->mModuleMgr;
1294         }
1295
1296         /**
1297          * Add or overwrite a module in this ApiMain instance. Intended for use by extending
1298          * classes who wish to add their own modules to their lexicon or override the
1299          * behavior of inherent ones.
1300          *
1301          * @deprecated since 1.21, Use getModuleManager()->addModule() instead.
1302          * @param string $name The identifier for this module.
1303          * @param $class ApiBase The class where this module is implemented.
1304          */
1305         protected function addModule( $name, $class ) {
1306                 $this->getModuleManager()->addModule( $name, 'action', $class );
1307         }
1308
1309         /**
1310          * Add or overwrite an output format for this ApiMain. Intended for use by extending
1311          * classes who wish to add to or modify current formatters.
1312          *
1313          * @deprecated since 1.21, Use getModuleManager()->addModule() instead.
1314          * @param string $name The identifier for this format.
1315          * @param $class ApiFormatBase The class implementing this format.
1316          */
1317         protected function addFormat( $name, $class ) {
1318                 $this->getModuleManager()->addModule( $name, 'format', $class );
1319         }
1320
1321         /**
1322          * Get the array mapping module names to class names
1323          * @deprecated since 1.21, Use getModuleManager()'s methods instead.
1324          * @return array
1325          */
1326         function getModules() {
1327                 return $this->getModuleManager()->getNamesWithClasses( 'action' );
1328         }
1329
1330         /**
1331          * Returns the list of supported formats in form ( 'format' => 'ClassName' )
1332          *
1333          * @since 1.18
1334          * @deprecated since 1.21, Use getModuleManager()'s methods instead.
1335          * @return array
1336          */
1337         public function getFormats() {
1338                 return $this->getModuleManager()->getNamesWithClasses( 'format' );
1339         }
1340 }
1341
1342 /**
1343  * This exception will be thrown when dieUsage is called to stop module execution.
1344  * The exception handling code will print a help screen explaining how this API may be used.
1345  *
1346  * @ingroup API
1347  */
1348 class UsageException extends MWException {
1349
1350         private $mCodestr;
1351
1352         /**
1353          * @var null|array
1354          */
1355         private $mExtraData;
1356
1357         /**
1358          * @param $message string
1359          * @param $codestr string
1360          * @param $code int
1361          * @param $extradata array|null
1362          */
1363         public function __construct( $message, $codestr, $code = 0, $extradata = null ) {
1364                 parent::__construct( $message, $code );
1365                 $this->mCodestr = $codestr;
1366                 $this->mExtraData = $extradata;
1367         }
1368
1369         /**
1370          * @return string
1371          */
1372         public function getCodeString() {
1373                 return $this->mCodestr;
1374         }
1375
1376         /**
1377          * @return array
1378          */
1379         public function getMessageArray() {
1380                 $result = array(
1381                         'code' => $this->mCodestr,
1382                         'info' => $this->getMessage()
1383                 );
1384                 if ( is_array( $this->mExtraData ) ) {
1385                         $result = array_merge( $result, $this->mExtraData );
1386                 }
1387
1388                 return $result;
1389         }
1390
1391         /**
1392          * @return string
1393          */
1394         public function __toString() {
1395                 return "{$this->getCodeString()}: {$this->getMessage()}";
1396         }
1397 }