includes/api/ApiMain.php

   1 <?php
   2
   3 /*
   4  * Created on Sep 4, 2006
   5  *
   6  * API for MediaWiki 1.8+
   7  *
   8  * Copyright (C) 2006 Yuri Astrakhan <Firstname><Lastname>@gmail.com
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License along
  21  * with this program; if not, write to the Free Software Foundation, Inc.,
  22  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  * http://www.gnu.org/copyleft/gpl.html
  24  */
  25
  26 if (!defined('MEDIAWIKI')) {
  27         // Eclipse helper - will be ignored in production
  28         require_once ('ApiBase.php');
  29 }
  30
  31 /**
  32  * @defgroup API API
  33  */
  34
  35 /**
  36  * This is the main API class, used for both external and internal processing.
  37  * When executed, it will create the requested formatter object,
  38  * instantiate and execute an object associated with the needed action,
  39  * and use formatter to print results.
  40  * In case of an exception, an error message will be printed using the same formatter.
  41  *
  42  * To use API from another application, run it using FauxRequest object, in which
  43  * case any internal exceptions will not be handled but passed up to the caller.
  44  * After successful execution, use getResult() for the resulting data.
  45  *
  46  * @ingroup API
  47  */
  48 class ApiMain extends ApiBase {
  49
  50         /**
  51          * When no format parameter is given, this format will be used
  52          */
  53         const API_DEFAULT_FORMAT = 'xmlfm';
  54
  55         /**
  56          * List of available modules: action name => module class
  57          */
  58         private static $Modules = array (
  59                 'login' => 'ApiLogin',
  60                 'logout' => 'ApiLogout',
  61                 'query' => 'ApiQuery',
  62                 'expandtemplates' => 'ApiExpandTemplates',
  63                 'parse' => 'ApiParse',
  64                 'opensearch' => 'ApiOpenSearch',
  65                 'feedwatchlist' => 'ApiFeedWatchlist',
  66                 'help' => 'ApiHelp',
  67                 'paraminfo' => 'ApiParamInfo',
  68
  69                 // Write modules
  70                 'purge' => 'ApiPurge',
  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                 'emailuser' => 'ApiEmailUser',
  80                 'watch' => 'ApiWatch',
  81                 'patrol' => 'ApiPatrol',
  82                 'import' => 'ApiImport',
  83         );
  84
  85         /**
  86          * List of available formats: format name => format class
  87          */
  88         private static $Formats = array (
  89                 'json' => 'ApiFormatJson',
  90                 'jsonfm' => 'ApiFormatJson',
  91                 'php' => 'ApiFormatPhp',
  92                 'phpfm' => 'ApiFormatPhp',
  93                 'wddx' => 'ApiFormatWddx',
  94                 'wddxfm' => 'ApiFormatWddx',
  95                 'xml' => 'ApiFormatXml',
  96                 'xmlfm' => 'ApiFormatXml',
  97                 'yaml' => 'ApiFormatYaml',
  98                 'yamlfm' => 'ApiFormatYaml',
  99                 'rawfm' => 'ApiFormatJson',
 100                 'txt' => 'ApiFormatTxt',
 101                 'txtfm' => 'ApiFormatTxt',
 102                 'dbg' => 'ApiFormatDbg',
 103                 'dbgfm' => 'ApiFormatDbg'
 104         );
 105
 106         /**
 107          * List of user roles that are specifically relevant to the API.
 108          * array( 'right' => array ( 'msg'    => 'Some message with a $1',
 109          *                           'params' => array ( $someVarToSubst ) ),
 110          *                          );
 111          */
 112         private static $mRights = array('writeapi' => array(
 113                                                 'msg' => 'Use of the write API',
 114                                                 'params' => array()
 115                                         ),
 116                                         'apihighlimits' => array(
 117                                                 '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.',
 118                                                 'params' => array (ApiMain::LIMIT_SML2, ApiMain::LIMIT_BIG2)
 119                                         )
 120         );
 121
 122
 123         private $mPrinter, $mModules, $mModuleNames, $mFormats, $mFormatNames;
 124         private $mResult, $mAction, $mShowVersions, $mEnableWrite, $mRequest, $mInternalMode, $mSquidMaxage;
 125
 126         /**
 127         * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 128         *
 129         * @param $request object - if this is an instance of FauxRequest, errors are thrown and no printing occurs
 130         * @param $enableWrite bool should be set to true if the api may modify data
 131         */
 132         public function __construct($request, $enableWrite = false) {
 133
 134                 $this->mInternalMode = ($request instanceof FauxRequest);
 135
 136                 // Special handling for the main module: $parent === $this
 137                 parent :: __construct($this, $this->mInternalMode ? 'main_int' : 'main');
 138
 139                 if (!$this->mInternalMode) {
 140
 141                         // Impose module restrictions.
 142                         // If the current user cannot read,
 143                         // Remove all modules other than login
 144                         global $wgUser;
 145
 146                         if( $request->getVal( 'callback' ) !== null ) {
 147                                 // JSON callback allows cross-site reads.
 148                                 // For safety, strip user credentials.
 149                                 wfDebug( "API: stripping user credentials for JSON callback\n" );
 150                                 $wgUser = new User();
 151                         }
 152                 }
 153
 154                 global $wgAPIModules; // extension modules
 155                 $this->mModules = $wgAPIModules + self :: $Modules;
 156
 157                 $this->mModuleNames = array_keys($this->mModules);
 158                 $this->mFormats = self :: $Formats;
 159                 $this->mFormatNames = array_keys($this->mFormats);
 160
 161                 $this->mResult = new ApiResult($this);
 162                 $this->mShowVersions = false;
 163                 $this->mEnableWrite = $enableWrite;
 164
 165                 $this->mRequest = & $request;
 166
 167                 $this->mSquidMaxage = -1; // flag for executeActionWithErrorHandling()
 168                 $this->mCommit = false;
 169         }
 170
 171         /**
 172          * Return true if the API was started by other PHP code using FauxRequest
 173          */
 174         public function isInternalMode() {
 175                 return $this->mInternalMode;
 176         }
 177
 178         /**
 179          * Return the request object that contains client's request
 180          */
 181         public function getRequest() {
 182                 return $this->mRequest;
 183         }
 184
 185         /**
 186          * Get the ApiResult object asscosiated with current request
 187          */
 188         public function getResult() {
 189                 return $this->mResult;
 190         }
 191
 192         /**
 193          * Set how long the response should be cached.
 194          */
 195         public function setCacheMaxAge($maxage) {
 196                 $this->mSquidMaxage = $maxage;
 197         }
 198
 199         /**
 200          * Create an instance of an output formatter by its name
 201          */
 202         public function createPrinterByName($format) {
 203                 if( !isset( $this->mFormats[$format] ) )
 204                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 205                 return new $this->mFormats[$format] ($this, $format);
 206         }
 207
 208         /**
 209          * Execute api request. Any errors will be handled if the API was called by the remote client.
 210          */
 211         public function execute() {
 212                 $this->profileIn();
 213                 if ($this->mInternalMode)
 214                         $this->executeAction();
 215                 else
 216                         $this->executeActionWithErrorHandling();
 217
 218                 $this->profileOut();
 219         }
 220
 221         /**
 222          * Execute an action, and in case of an error, erase whatever partial results
 223          * have been accumulated, and replace it with an error message and a help screen.
 224          */
 225         protected function executeActionWithErrorHandling() {
 226
 227                 // In case an error occurs during data output,
 228                 // clear the output buffer and print just the error information
 229                 ob_start();
 230
 231                 try {
 232                         $this->executeAction();
 233                 } catch (Exception $e) {
 234                         // Log it
 235                         if ( $e instanceof MWException ) {
 236                                 wfDebugLog( 'exception', $e->getLogMessage() );
 237                         }
 238
 239                         //
 240                         // Handle any kind of exception by outputing properly formatted error message.
 241                         // If this fails, an unhandled exception should be thrown so that global error
 242                         // handler will process and log it.
 243                         //
 244
 245                         $errCode = $this->substituteResultWithError($e);
 246
 247                         // Error results should not be cached
 248                         $this->setCacheMaxAge(0);
 249
 250                         $headerStr = 'MediaWiki-API-Error: ' . $errCode;
 251                         if ($e->getCode() === 0)
 252                                 header($headerStr);
 253                         else
 254                                 header($headerStr, true, $e->getCode());
 255
 256                         // Reset and print just the error message
 257                         ob_clean();
 258
 259                         // If the error occured during printing, do a printer->profileOut()
 260                         $this->mPrinter->safeProfileOut();
 261                         $this->printResult(true);
 262                 }
 263
 264                 if($this->mSquidMaxage == -1)
 265                 {
 266                         # Nobody called setCacheMaxAge(), use the (s)maxage parameters
 267                         $smaxage = $this->getParameter('smaxage');
 268                         $maxage = $this->getParameter('maxage');
 269                 }
 270                 else
 271                         $smaxage = $maxage = $this->mSquidMaxage;
 272
 273                 // Set the cache expiration at the last moment, as any errors may change the expiration.
 274                 // if $this->mSquidMaxage == 0, the expiry time is set to the first second of unix epoch
 275                 $exp = min($smaxage, $maxage);
 276                 $expires = ($exp == 0 ? 1 : time() + $exp);
 277                 header('Expires: ' . wfTimestamp(TS_RFC2822, $expires));
 278                 header('Cache-Control: s-maxage=' . $smaxage . ', must-revalidate, max-age=' . $maxage);
 279
 280                 if($this->mPrinter->getIsHtml())
 281                         echo wfReportTime();
 282
 283                 ob_end_flush();
 284         }
 285
 286         /**
 287          * Replace the result data with the information about an exception.
 288          * Returns the error code
 289          */
 290         protected function substituteResultWithError($e) {
 291
 292                         // Printer may not be initialized if the extractRequestParams() fails for the main module
 293                         if (!isset ($this->mPrinter)) {
 294                                 // The printer has not been created yet. Try to manually get formatter value.
 295                                 $value = $this->getRequest()->getVal('format', self::API_DEFAULT_FORMAT);
 296                                 if (!in_array($value, $this->mFormatNames))
 297                                         $value = self::API_DEFAULT_FORMAT;
 298
 299                                 $this->mPrinter = $this->createPrinterByName($value);
 300                                 if ($this->mPrinter->getNeedsRawData())
 301                                         $this->getResult()->setRawMode();
 302                         }
 303
 304                         if ($e instanceof UsageException) {
 305                                 //
 306                                 // User entered incorrect parameters - print usage screen
 307                                 //
 308                                 $errMessage = array (
 309                                 'code' => $e->getCodeString(),
 310                                 'info' => $e->getMessage());
 311
 312                                 // Only print the help message when this is for the developer, not runtime
 313                                 if ($this->mPrinter->getIsHtml() || $this->mAction == 'help')
 314                                         ApiResult :: setContent($errMessage, $this->makeHelpMsg());
 315
 316                         } else {
 317                                 global $wgShowSQLErrors, $wgShowExceptionDetails;
 318                                 //
 319                                 // Something is seriously wrong
 320                                 //
 321                                 if ( ( $e instanceof DBQueryError ) && !$wgShowSQLErrors ) {
 322                                         $info = "Database query error";
 323                                 } else {
 324                                         $info = "Exception Caught: {$e->getMessage()}";
 325                                 }
 326
 327                                 $errMessage = array (
 328                                         'code' => 'internal_api_error_'. get_class($e),
 329                                         'info' => $info,
 330                                 );
 331                                 ApiResult :: setContent($errMessage, $wgShowExceptionDetails ? "\n\n{$e->getTraceAsString()}\n\n" : "" );
 332                         }
 333
 334                         $this->getResult()->reset();
 335                         $this->getResult()->disableSizeCheck();
 336                         // Re-add the id
 337                         $requestid = $this->getParameter('requestid');
 338                         if(!is_null($requestid))
 339                                 $this->getResult()->addValue(null, 'requestid', $requestid);
 340                         $this->getResult()->addValue(null, 'error', $errMessage);
 341
 342                 return $errMessage['code'];
 343         }
 344
 345         /**
 346          * Execute the actual module, without any error handling
 347          */
 348         protected function executeAction() {
 349                 // First add the id to the top element
 350                 $requestid = $this->getParameter('requestid');
 351                 if(!is_null($requestid))
 352                         $this->getResult()->addValue(null, 'requestid', $requestid);
 353
 354                 $params = $this->extractRequestParams();
 355
 356                 $this->mShowVersions = $params['version'];
 357                 $this->mAction = $params['action'];
 358
 359                 if( !is_string( $this->mAction ) ) {
 360                         $this->dieUsage( "The API requires a valid action parameter", 'unknown_action' );
 361                 }
 362
 363                 // Instantiate the module requested by the user
 364                 $module = new $this->mModules[$this->mAction] ($this, $this->mAction);
 365
 366                 if( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
 367                         // Check for maxlag
 368                         global $wgShowHostnames;
 369                         $maxLag = $params['maxlag'];
 370                         list( $host, $lag ) = wfGetLB()->getMaxLag();
 371                         if ( $lag > $maxLag ) {
 372                                 header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
 373                                 header( 'X-Database-Lag: ' . intval( $lag ) );
 374                                 // XXX: should we return a 503 HTTP error code like wfMaxlagError() does?
 375                                 if( $wgShowHostnames ) {
 376                                         $this->dieUsage( "Waiting for $host: $lag seconds lagged", 'maxlag' );
 377                                 } else {
 378                                         $this->dieUsage( "Waiting for a database server: $lag seconds lagged", 'maxlag' );
 379                                 }
 380                                 return;
 381                         }
 382                 }
 383
 384                 global $wgUser;
 385                 if ($module->isReadMode() && !$wgUser->isAllowed('read'))
 386                         $this->dieUsageMsg(array('readrequired'));
 387                 if ($module->isWriteMode()) {
 388                         if (!$this->mEnableWrite)
 389                                 $this->dieUsageMsg(array('writedisabled'));
 390                         if (!$wgUser->isAllowed('writeapi'))
 391                                 $this->dieUsageMsg(array('writerequired'));
 392                         if (wfReadOnly())
 393                                 $this->dieUsageMsg(array('readonlytext'));
 394                 }
 395
 396                 if (!$this->mInternalMode) {
 397                         // Ignore mustBePosted() for internal calls
 398                         if($module->mustBePosted() && !$this->mRequest->wasPosted())
 399                                 $this->dieUsage("The {$this->mAction} module requires a POST request", 'mustbeposted');
 400
 401                         // See if custom printer is used
 402                         $this->mPrinter = $module->getCustomPrinter();
 403                         if (is_null($this->mPrinter)) {
 404                                 // Create an appropriate printer
 405                                 $this->mPrinter = $this->createPrinterByName($params['format']);
 406                         }
 407
 408                         if ($this->mPrinter->getNeedsRawData())
 409                                 $this->getResult()->setRawMode();
 410                 }
 411
 412                 // Execute
 413                 $module->profileIn();
 414                 $module->execute();
 415                 wfRunHooks('APIAfterExecute', array(&$module));
 416                 $module->profileOut();
 417
 418                 if (!$this->mInternalMode) {
 419                         // Print result data
 420                         $this->printResult(false);
 421                 }
 422         }
 423
 424         /**
 425          * Print results using the current printer
 426          */
 427         protected function printResult($isError) {
 428                 $this->getResult()->cleanUpUTF8();
 429                 $printer = $this->mPrinter;
 430                 $printer->profileIn();
 431
 432                 /* If the help message is requested in the default (xmlfm) format,
 433                  * tell the printer not to escape ampersands so that our links do
 434                  * not break. */
 435                 $printer->setUnescapeAmps ( ( $this->mAction == 'help' || $isError )
 436                                 && $printer->getFormat() == 'XML' && $printer->getIsHtml() );
 437
 438                 $printer->initPrinter($isError);
 439
 440                 $printer->execute();
 441                 $printer->closePrinter();
 442                 $printer->profileOut();
 443         }
 444
 445         public function isReadMode() {
 446                 return false;
 447         }
 448
 449         /**
 450          * See ApiBase for description.
 451          */
 452         public function getAllowedParams() {
 453                 return array (
 454                         'format' => array (
 455                                 ApiBase :: PARAM_DFLT => ApiMain :: API_DEFAULT_FORMAT,
 456                                 ApiBase :: PARAM_TYPE => $this->mFormatNames
 457                         ),
 458                         'action' => array (
 459                                 ApiBase :: PARAM_DFLT => 'help',
 460                                 ApiBase :: PARAM_TYPE => $this->mModuleNames
 461                         ),
 462                         'version' => false,
 463                         'maxlag'  => array (
 464                                 ApiBase :: PARAM_TYPE => 'integer'
 465                         ),
 466                         'smaxage' => array (
 467                                 ApiBase :: PARAM_TYPE => 'integer',
 468                                 ApiBase :: PARAM_DFLT => 0
 469                         ),
 470                         'maxage' => array (
 471                                 ApiBase :: PARAM_TYPE => 'integer',
 472                                 ApiBase :: PARAM_DFLT => 0
 473                         ),
 474                         'requestid' => null,
 475                 );
 476         }
 477
 478         /**
 479          * See ApiBase for description.
 480          */
 481         public function getParamDescription() {
 482                 return array (
 483                         'format' => 'The format of the output',
 484                         'action' => 'What action you would like to perform',
 485                         'version' => 'When showing help, include version for each module',
 486                         'maxlag' => 'Maximum lag',
 487                         'smaxage' => 'Set the s-maxage header to this many seconds. Errors are never cached',
 488                         'maxage' => 'Set the max-age header to this many seconds. Errors are never cached',
 489                         'requestid' => 'Request ID to distinguish requests. This will just be output back to you',
 490                 );
 491         }
 492
 493         /**
 494          * See ApiBase for description.
 495          */
 496         public function getDescription() {
 497                 return array (
 498                         '',
 499                         '',
 500                         '******************************************************************',
 501                         '**                                                              **',
 502                         '**  This is an auto-generated MediaWiki API documentation page  **',
 503                         '**                                                              **',
 504                         '**                  Documentation and Examples:                 **',
 505                         '**               http://www.mediawiki.org/wiki/API              **',
 506                         '**                                                              **',
 507                         '******************************************************************',
 508                         '',
 509                         'Status:          All features shown on this page should be working, but the API',
 510                         '                 is still in active development, and  may change at any time.',
 511                         '                 Make sure to monitor our mailing list for any updates.',
 512                         '',
 513                         'Documentation:   http://www.mediawiki.org/wiki/API',
 514                         'Mailing list:    http://lists.wikimedia.org/mailman/listinfo/mediawiki-api',
 515                         'Bugs & Requests: http://bugzilla.wikimedia.org/buglist.cgi?component=API&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&order=bugs.delta_ts',
 516                         '',
 517                         '',
 518                         '',
 519                         '',
 520                         '',
 521                 );
 522         }
 523
 524         /**
 525          * Returns an array of strings with credits for the API
 526          */
 527         protected function getCredits() {
 528                 return array(
 529                         'API developers:',
 530                         '    Roan Kattouw <Firstname>.<Lastname>@home.nl (lead developer Sep 2007-present)',
 531                         '    Victor Vasiliev - vasilvv at gee mail dot com',
 532                         '    Bryan Tong Minh - bryan . tongminh @ gmail . com',
 533                         '    Yuri Astrakhan <Firstname><Lastname>@gmail.com (creator, lead developer Sep 2006-Sep 2007)',
 534                         '',
 535                         'Please send your comments, suggestions and questions to mediawiki-api@lists.wikimedia.org',
 536                         'or file a bug report at http://bugzilla.wikimedia.org/'
 537                 );
 538         }
 539
 540         /**
 541          * Override the parent to generate help messages for all available modules.
 542          */
 543         public function makeHelpMsg() {
 544
 545                 $this->mPrinter->setHelp();
 546
 547                 // Use parent to make default message for the main module
 548                 $msg = parent :: makeHelpMsg();
 549
 550                 $astriks = str_repeat('*** ', 10);
 551                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
 552                 foreach( $this->mModules as $moduleName => $unused ) {
 553                         $module = new $this->mModules[$moduleName] ($this, $moduleName);
 554                         $msg .= self::makeHelpMsgHeader($module, 'action');
 555                         $msg2 = $module->makeHelpMsg();
 556                         if ($msg2 !== false)
 557                                 $msg .= $msg2;
 558                         $msg .= "\n";
 559                 }
 560
 561                 $msg .= "\n$astriks Permissions $astriks\n\n";
 562                 foreach ( self :: $mRights as $right => $rightMsg ) {
 563                         $groups = User::getGroupsWithPermission( $right );
 564                         $msg .= "* " . $right . " *\n  " . wfMsgReplaceArgs( $rightMsg[ 'msg' ], $rightMsg[ 'params' ] ) .
 565                                                 "\nGranted to:\n  " . str_replace( "*", "all", implode( ", ", $groups ) ) . "\n";
 566
 567                 }
 568
 569                 $msg .= "\n$astriks Formats  $astriks\n\n";
 570                 foreach( $this->mFormats as $formatName => $unused ) {
 571                         $module = $this->createPrinterByName($formatName);
 572                         $msg .= self::makeHelpMsgHeader($module, 'format');
 573                         $msg2 = $module->makeHelpMsg();
 574                         if ($msg2 !== false)
 575                                 $msg .= $msg2;
 576                         $msg .= "\n";
 577                 }
 578
 579                 $msg .= "\n*** Credits: ***\n   " . implode("\n   ", $this->getCredits()) . "\n";
 580
 581
 582                 return $msg;
 583         }
 584
 585         public static function makeHelpMsgHeader($module, $paramName) {
 586                 $modulePrefix = $module->getModulePrefix();
 587                 if (strval($modulePrefix) !== '')
 588                         $modulePrefix = "($modulePrefix) ";
 589
 590                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
 591         }
 592
 593         private $mIsBot = null;
 594         private $mIsSysop = null;
 595         private $mCanApiHighLimits = null;
 596
 597         /**
 598          * Returns true if the currently logged in user is a bot, false otherwise
 599          * OBSOLETE, use canApiHighLimits() instead
 600          */
 601         public function isBot() {
 602                 if (!isset ($this->mIsBot)) {
 603                         global $wgUser;
 604                         $this->mIsBot = $wgUser->isAllowed('bot');
 605                 }
 606                 return $this->mIsBot;
 607         }
 608
 609         /**
 610          * Similar to isBot(), this method returns true if the logged in user is
 611          * a sysop, and false if not.
 612          * OBSOLETE, use canApiHighLimits() instead
 613          */
 614         public function isSysop() {
 615                 if (!isset ($this->mIsSysop)) {
 616                         global $wgUser;
 617                         $this->mIsSysop = in_array( 'sysop', $wgUser->getGroups());
 618                 }
 619
 620                 return $this->mIsSysop;
 621         }
 622
 623         /**
 624          * Check whether the current user is allowed to use high limits
 625          * @return bool
 626          */
 627         public function canApiHighLimits() {
 628                 if (!isset($this->mCanApiHighLimits)) {
 629                         global $wgUser;
 630                         $this->mCanApiHighLimits = $wgUser->isAllowed('apihighlimits');
 631                 }
 632
 633                 return $this->mCanApiHighLimits;
 634         }
 635
 636         /**
 637          * Check whether the user wants us to show version information in the API help
 638          * @return bool
 639          */
 640         public function getShowVersions() {
 641                 return $this->mShowVersions;
 642         }
 643
 644         /**
 645          * Returns the version information of this file, plus it includes
 646          * the versions for all files that are not callable proper API modules
 647          */
 648         public function getVersion() {
 649                 $vers = array ();
 650                 $vers[] = 'MediaWiki: ' . SpecialVersion::getVersion() . "\n    http://svn.wikimedia.org/viewvc/mediawiki/trunk/phase3/";
 651                 $vers[] = __CLASS__ . ': $Id$';
 652                 $vers[] = ApiBase :: getBaseVersion();
 653                 $vers[] = ApiFormatBase :: getBaseVersion();
 654                 $vers[] = ApiQueryBase :: getBaseVersion();
 655                 $vers[] = ApiFormatFeedWrapper :: getVersion(); // not accessible with format=xxx
 656                 return $vers;
 657         }
 658
 659         /**
 660          * Add or overwrite a module in this ApiMain instance. Intended for use by extending
 661          * classes who wish to add their own modules to their lexicon or override the
 662          * behavior of inherent ones.
 663          *
 664          * @access protected
 665          * @param $mdlName String The identifier for this module.
 666          * @param $mdlClass String The class where this module is implemented.
 667          */
 668         protected function addModule( $mdlName, $mdlClass ) {
 669                 $this->mModules[$mdlName] = $mdlClass;
 670         }
 671
 672         /**
 673          * Add or overwrite an output format for this ApiMain. Intended for use by extending
 674          * classes who wish to add to or modify current formatters.
 675          *
 676          * @access protected
 677          * @param $fmtName The identifier for this format.
 678          * @param $fmtClass The class implementing this format.
 679          */
 680         protected function addFormat( $fmtName, $fmtClass ) {
 681                 $this->mFormats[$fmtName] = $fmtClass;
 682         }
 683
 684         /**
 685          * Get the array mapping module names to class names
 686          */
 687         function getModules() {
 688                 return $this->mModules;
 689         }
 690 }
 691
 692 /**
 693  * This exception will be thrown when dieUsage is called to stop module execution.
 694  * The exception handling code will print a help screen explaining how this API may be used.
 695  *
 696  * @ingroup API
 697  */
 698 class UsageException extends Exception {
 699
 700         private $mCodestr;
 701
 702         public function __construct($message, $codestr, $code = 0) {
 703                 parent :: __construct($message, $code);
 704                 $this->mCodestr = $codestr;
 705         }
 706         public function getCodeString() {
 707                 return $this->mCodestr;
 708         }
 709         public function __toString() {
 710                 return "{$this->getCodeString()}: {$this->getMessage()}";
 711         }
 712 }