includes/api/ApiMain.php

   1 <?php
   2
   3 /**
   4  * Created on Sep 4, 2006
   5  *
   6  * API for MediaWiki 1.8+
   7  *
   8  * Copyright © 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                 'go' => 'ApiGo',
  67                 'help' => 'ApiHelp',
  68                 'paraminfo' => 'ApiParamInfo',
  69
  70                 // Write modules
  71                 'purge' => 'ApiPurge',
  72                 'rollback' => 'ApiRollback',
  73                 'delete' => 'ApiDelete',
  74                 'undelete' => 'ApiUndelete',
  75                 'protect' => 'ApiProtect',
  76                 'block' => 'ApiBlock',
  77                 'unblock' => 'ApiUnblock',
  78                 'move' => 'ApiMove',
  79                 'edit' => 'ApiEditPage',
  80                 'upload' => 'ApiUpload',
  81                 'emailuser' => 'ApiEmailUser',
  82                 'watch' => 'ApiWatch',
  83                 'patrol' => 'ApiPatrol',
  84                 'import' => 'ApiImport',
  85                 'userrights' => 'ApiUserrights',
  86         );
  87
  88         /**
  89          * List of available formats: format name => format class
  90          */
  91         private static $Formats = array(
  92                 'json' => 'ApiFormatJson',
  93                 'jsonfm' => 'ApiFormatJson',
  94                 'php' => 'ApiFormatPhp',
  95                 'phpfm' => 'ApiFormatPhp',
  96                 'wddx' => 'ApiFormatWddx',
  97                 'wddxfm' => 'ApiFormatWddx',
  98                 'xml' => 'ApiFormatXml',
  99                 'xmlfm' => 'ApiFormatXml',
 100                 'yaml' => 'ApiFormatYaml',
 101                 'yamlfm' => 'ApiFormatYaml',
 102                 'rawfm' => 'ApiFormatJson',
 103                 'txt' => 'ApiFormatTxt',
 104                 'txtfm' => 'ApiFormatTxt',
 105                 'dbg' => 'ApiFormatDbg',
 106                 'dbgfm' => 'ApiFormatDbg'
 107         );
 108
 109         /**
 110          * List of user roles that are specifically relevant to the API.
 111          * array( 'right' => array ( 'msg'    => 'Some message with a $1',
 112          *                           'params' => array ( $someVarToSubst ) ),
 113          *                          );
 114          */
 115         private static $mRights = array(
 116                 'writeapi' => array(
 117                         'msg' => 'Use of the write API',
 118                         'params' => array()
 119                 ),
 120                 'apihighlimits' => array(
 121                         '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.',
 122                         'params' => array( ApiMain::LIMIT_SML2, ApiMain::LIMIT_BIG2 )
 123                 )
 124         );
 125
 126         private $mPrinter, $mModules, $mModuleNames, $mFormats, $mFormatNames;
 127         private $mResult, $mAction, $mShowVersions, $mEnableWrite, $mRequest;
 128         private $mInternalMode, $mSquidMaxage, $mModule;
 129
 130         private $mCacheControl = array( 'must-revalidate' => true );
 131
 132         /**
 133          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 134          *
 135          * @param $request object - if this is an instance of FauxRequest, errors are thrown and no printing occurs
 136          * @param $enableWrite bool should be set to true if the api may modify data
 137          */
 138         public function __construct( $request, $enableWrite = false ) {
 139                 $this->mInternalMode = ( $request instanceof FauxRequest );
 140
 141                 // Special handling for the main module: $parent === $this
 142                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 143
 144                 if ( !$this->mInternalMode ) {
 145                         // Impose module restrictions.
 146                         // If the current user cannot read,
 147                         // Remove all modules other than login
 148                         global $wgUser;
 149
 150                         if ( $request->getVal( 'callback' ) !== null ) {
 151                                 // JSON callback allows cross-site reads.
 152                                 // For safety, strip user credentials.
 153                                 wfDebug( "API: stripping user credentials for JSON callback\n" );
 154                                 $wgUser = new User();
 155                         }
 156                 }
 157
 158                 global $wgAPIModules; // extension modules
 159                 $this->mModules = $wgAPIModules + self::$Modules;
 160
 161                 $this->mModuleNames = array_keys( $this->mModules );
 162                 $this->mFormats = self::$Formats;
 163                 $this->mFormatNames = array_keys( $this->mFormats );
 164
 165                 $this->mResult = new ApiResult( $this );
 166                 $this->mShowVersions = false;
 167                 $this->mEnableWrite = $enableWrite;
 168
 169                 $this->mRequest = &$request;
 170
 171                 $this->mSquidMaxage = -1; // flag for executeActionWithErrorHandling()
 172                 $this->mCommit = false;
 173         }
 174
 175         /**
 176          * Return true if the API was started by other PHP code using FauxRequest
 177          */
 178         public function isInternalMode() {
 179                 return $this->mInternalMode;
 180         }
 181
 182         /**
 183          * Return the request object that contains client's request
 184          */
 185         public function getRequest() {
 186                 return $this->mRequest;
 187         }
 188
 189         /**
 190          * Get the ApiResult object associated with current request
 191          */
 192         public function getResult() {
 193                 return $this->mResult;
 194         }
 195
 196         /**
 197          * Get the API module object. Only works after executeAction()
 198          */
 199         public function getModule() {
 200                 return $this->mModule;
 201         }
 202
 203         /**
 204          * Only kept for backwards compatibility
 205          * @deprecated Use isWriteMode() instead
 206          */
 207         public function requestWriteMode() {
 208                 if ( !$this->mEnableWrite ) {
 209                         $this->dieUsageMsg( array( 'writedisabled' ) );
 210                 }
 211                 if ( wfReadOnly() ) {
 212                         $this->dieUsageMsg( array( 'readonlytext' ) );
 213                 }
 214         }
 215
 216         /**
 217          * Set how long the response should be cached.
 218          */
 219         public function setCacheMaxAge( $maxage ) {
 220                 $this->setCacheControl( array(
 221                         'max-age' => $maxage,
 222                         's-maxage' => $maxage
 223                 ) );
 224         }
 225
 226         /**
 227          * Set directives (key/value pairs) for the Cache-Control header.
 228          * Boolean values will be formatted as such, by including or omitting
 229          * without an equals sign.
 230          */
 231         public function setCacheControl( $directives ) {
 232                 $this->mCacheControl = $directives + $this->mCacheControl;
 233         }
 234
 235         /**
 236          * Create an instance of an output formatter by its name
 237          */
 238         public function createPrinterByName( $format ) {
 239                 if ( !isset( $this->mFormats[$format] ) ) {
 240                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 241                 }
 242                 return new $this->mFormats[$format] ( $this, $format );
 243         }
 244
 245         /**
 246          * Execute api request. Any errors will be handled if the API was called by the remote client.
 247          */
 248         public function execute() {
 249                 $this->profileIn();
 250                 if ( $this->mInternalMode ) {
 251                         $this->executeAction();
 252                 } else {
 253                         $this->executeActionWithErrorHandling();
 254                 }
 255
 256                 $this->profileOut();
 257         }
 258
 259         /**
 260          * Execute an action, and in case of an error, erase whatever partial results
 261          * have been accumulated, and replace it with an error message and a help screen.
 262          */
 263         protected function executeActionWithErrorHandling() {
 264                 // In case an error occurs during data output,
 265                 // clear the output buffer and print just the error information
 266                 ob_start();
 267
 268                 try {
 269                         $this->executeAction();
 270                 } catch ( Exception $e ) {
 271                         // Log it
 272                         if ( $e instanceof MWException ) {
 273                                 wfDebugLog( 'exception', $e->getLogMessage() );
 274                         }
 275
 276                         //
 277                         // Handle any kind of exception by outputing properly formatted error message.
 278                         // If this fails, an unhandled exception should be thrown so that global error
 279                         // handler will process and log it.
 280                         //
 281
 282                         $errCode = $this->substituteResultWithError( $e );
 283
 284                         // Error results should not be cached
 285                         $this->setCacheMaxAge( 0 );
 286
 287                         $headerStr = 'MediaWiki-API-Error: ' . $errCode;
 288                         if ( $e->getCode() === 0 ) {
 289                                 header( $headerStr );
 290                         } else {
 291                                 header( $headerStr, true, $e->getCode() );
 292                         }
 293
 294                         // Reset and print just the error message
 295                         ob_clean();
 296
 297                         // If the error occured during printing, do a printer->profileOut()
 298                         $this->mPrinter->safeProfileOut();
 299                         $this->printResult( true );
 300                 }
 301
 302                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 303                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 304                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 305                 }
 306                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 307                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 308                 }
 309
 310                 // Set the cache expiration at the last moment, as any errors may change the expiration.
 311                 // if $this->mSquidMaxage == 0, the expiry time is set to the first second of unix epoch
 312                 $exp = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 313                 $expires = ( $exp == 0 ? 1 : time() + $exp );
 314                 header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expires ) );
 315
 316                 // Construct the Cache-Control header
 317                 $ccHeader = '';
 318                 $separator = '';
 319                 foreach ( $this->mCacheControl as $name => $value ) {
 320                         if ( is_bool( $value ) ) {
 321                                 if ( $value ) {
 322                                         $ccHeader .= $separator . $name;
 323                                         $separator = ', ';
 324                                 }
 325                         } else {
 326                                 $ccHeader .= $separator . "$name=$value";
 327                                 $separator = ', ';
 328                         }
 329                 }
 330
 331                 header( "Cache-Control: $ccHeader" );
 332
 333                 if ( $this->mPrinter->getIsHtml() ) {
 334                         echo wfReportTime();
 335                 }
 336
 337                 ob_end_flush();
 338         }
 339
 340         /**
 341          * Replace the result data with the information about an exception.
 342          * Returns the error code
 343          */
 344         protected function substituteResultWithError( $e ) {
 345                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 346                 if ( !isset ( $this->mPrinter ) ) {
 347                         // The printer has not been created yet. Try to manually get formatter value.
 348                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 349                         if ( !in_array( $value, $this->mFormatNames ) ) {
 350                                 $value = self::API_DEFAULT_FORMAT;
 351                         }
 352
 353                         $this->mPrinter = $this->createPrinterByName( $value );
 354                         if ( $this->mPrinter->getNeedsRawData() ) {
 355                                 $this->getResult()->setRawMode();
 356                         }
 357                 }
 358
 359                 if ( $e instanceof UsageException ) {
 360                         //
 361                         // User entered incorrect parameters - print usage screen
 362                         //
 363                         $errMessage = $e->getMessageArray();
 364
 365                         // Only print the help message when this is for the developer, not runtime
 366                         if ( $this->mPrinter->getWantsHelp() || $this->mAction == 'help' ) {
 367                                 ApiResult::setContent( $errMessage, $this->makeHelpMsg() );
 368                         }
 369
 370                 } else {
 371                         global $wgShowSQLErrors, $wgShowExceptionDetails;
 372                         //
 373                         // Something is seriously wrong
 374                         //
 375                         if ( ( $e instanceof DBQueryError ) && !$wgShowSQLErrors ) {
 376                                 $info = 'Database query error';
 377                         } else {
 378                                 $info = "Exception Caught: {$e->getMessage()}";
 379                         }
 380
 381                         $errMessage = array(
 382                                 'code' => 'internal_api_error_' . get_class( $e ),
 383                                 'info' => $info,
 384                         );
 385                         ApiResult::setContent( $errMessage, $wgShowExceptionDetails ? "\n\n{$e->getTraceAsString()}\n\n" : '' );
 386                 }
 387
 388                 $this->getResult()->reset();
 389                 $this->getResult()->disableSizeCheck();
 390                 // Re-add the id
 391                 $requestid = $this->getParameter( 'requestid' );
 392                 if ( !is_null( $requestid ) ) {
 393                         $this->getResult()->addValue( null, 'requestid', $requestid );
 394                 }
 395                 $this->getResult()->addValue( null, 'error', $errMessage );
 396
 397                 return $errMessage['code'];
 398         }
 399
 400         /**
 401          * Set up for the execution.
 402          */
 403         protected function setupExecuteAction() {
 404                 // First add the id to the top element
 405                 $requestid = $this->getParameter( 'requestid' );
 406                 if ( !is_null( $requestid ) ) {
 407                         $this->getResult()->addValue( null, 'requestid', $requestid );
 408                 }
 409
 410                 $params = $this->extractRequestParams();
 411
 412                 $this->mShowVersions = $params['version'];
 413                 $this->mAction = $params['action'];
 414
 415                 if ( !is_string( $this->mAction ) ) {
 416                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 417                 }
 418
 419                 return $params;
 420         }
 421
 422         /**
 423          * Set up the module for response
 424          * @return Object the module that will handle this action
 425          */
 426         protected function setupModule() {
 427                 // Instantiate the module requested by the user
 428                 $module = new $this->mModules[$this->mAction] ( $this, $this->mAction );
 429                 $this->mModule = $module;
 430
 431                 $moduleParams = $module->extractRequestParams();
 432
 433                 // Die if token required, but not provided (unless there is a gettoken parameter)
 434                 $salt = $module->getTokenSalt();
 435                 if ( $salt !== false && !isset( $moduleParams['gettoken'] ) ) {
 436                         if ( !isset( $moduleParams['token'] ) ) {
 437                                 $this->dieUsageMsg( array( 'missingparam', 'token' ) );
 438                         } else {
 439                                 global $wgUser;
 440                                 if ( !$wgUser->matchEditToken( $moduleParams['token'], $salt ) ) {
 441                                         $this->dieUsageMsg( array( 'sessionfailure' ) );
 442                                 }
 443                         }
 444                 }
 445                 return $module;
 446         }
 447
 448         /**
 449          * Check the max lag if necessary
 450          * @param $module ApiBase object: Api module being used
 451          * @param $params Array an array containing the request parameters.
 452          * @return boolean True on success, false should exit immediately
 453          */
 454         protected function checkMaxLag($module, $params) {
 455                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
 456                         // Check for maxlag
 457                         global $wgShowHostnames;
 458                         $maxLag = $params['maxlag'];
 459                         list( $host, $lag ) = wfGetLB()->getMaxLag();
 460                         if ( $lag > $maxLag ) {
 461                                 header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
 462                                 header( 'X-Database-Lag: ' . intval( $lag ) );
 463                                 if ( $wgShowHostnames ) {
 464                                         $this->dieUsage( "Waiting for $host: $lag seconds lagged", 'maxlag' );
 465                                 } else {
 466                                         $this->dieUsage( "Waiting for a database server: $lag seconds lagged", 'maxlag' );
 467                                 }
 468                                 return false;
 469                         }
 470                 }
 471                 return true;
 472         }
 473
 474
 475         /**
 476          * Check for sufficient permissions to execute
 477          * @param $module object An Api module
 478          */
 479         protected function checkExecutePermissions($module) {
 480                 global $wgUser, $wgGroupPermissions;
 481                 if ( $module->isReadMode() && !$wgGroupPermissions['*']['read'] && !$wgUser->isAllowed( 'read' ) )
 482                 {
 483                         $this->dieUsageMsg( array( 'readrequired' ) );
 484                 }
 485                 if ( $module->isWriteMode() ) {
 486                         if ( !$this->mEnableWrite ) {
 487                                 $this->dieUsageMsg( array( 'writedisabled' ) );
 488                         }
 489                         if ( !$wgUser->isAllowed( 'writeapi' ) ) {
 490                                 $this->dieUsageMsg( array( 'writerequired' ) );
 491                         }
 492                         if ( wfReadOnly() ) {
 493                                 $this->dieReadOnly();
 494                         }
 495                 }
 496         }
 497
 498         /**
 499          * Check POST for external response and setup result printer
 500          * @param $module object An Api module
 501          * @param $params Array an array with the request parameters
 502          */
 503         protected function setupExternalResponse($module, $params) {
 504                 // Ignore mustBePosted() for internal calls
 505                 if ( $module->mustBePosted() && !$this->mRequest->wasPosted() ) {
 506                         $this->dieUsageMsg( array( 'mustbeposted', $this->mAction ) );
 507                 }
 508
 509                 // See if custom printer is used
 510                 $this->mPrinter = $module->getCustomPrinter();
 511                 if ( is_null( $this->mPrinter ) ) {
 512                         // Create an appropriate printer
 513                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
 514                 }
 515
 516                 if ( $this->mPrinter->getNeedsRawData() ) {
 517                         $this->getResult()->setRawMode();
 518                 }
 519         }
 520
 521         /**
 522          * Execute the actual module, without any error handling
 523          */
 524         protected function executeAction() {
 525                 $params = $this->setupExecuteAction();
 526                 $module = $this->setupModule();
 527
 528                 $this->checkExecutePermissions($module);
 529
 530                 if(!$this->checkMaxLag($module, $params)) return;
 531
 532                 if ( !$this->mInternalMode ) {
 533                         $this->setupExternalResponse($module, $params);
 534                 }
 535
 536                 // Execute
 537                 $module->profileIn();
 538                 $module->execute();
 539                 wfRunHooks( 'APIAfterExecute', array( &$module ) );
 540                 $module->profileOut();
 541
 542                 if ( !$this->mInternalMode ) {
 543                         // Print result data
 544                         $this->printResult( false );
 545                 }
 546         }
 547
 548         /**
 549          * Print results using the current printer
 550          */
 551         protected function printResult( $isError ) {
 552                 $this->getResult()->cleanUpUTF8();
 553                 $printer = $this->mPrinter;
 554                 $printer->profileIn();
 555
 556                 /**
 557                  * If the help message is requested in the default (xmlfm) format,
 558                  * tell the printer not to escape ampersands so that our links do
 559                  * not break.
 560                  */
 561                 $printer->setUnescapeAmps( ( $this->mAction == 'help' || $isError )
 562                                 && $printer->getFormat() == 'XML' && $printer->getIsHtml() );
 563
 564                 $printer->initPrinter( $isError );
 565
 566                 $printer->execute();
 567                 $printer->closePrinter();
 568                 $printer->profileOut();
 569         }
 570
 571         public function isReadMode() {
 572                 return false;
 573         }
 574
 575         /**
 576          * See ApiBase for description.
 577          */
 578         public function getAllowedParams() {
 579                 return array(
 580                         'format' => array(
 581                                 ApiBase::PARAM_DFLT => ApiMain::API_DEFAULT_FORMAT,
 582                                 ApiBase::PARAM_TYPE => $this->mFormatNames
 583                         ),
 584                         'action' => array(
 585                                 ApiBase::PARAM_DFLT => 'help',
 586                                 ApiBase::PARAM_TYPE => $this->mModuleNames
 587                         ),
 588                         'version' => false,
 589                         'maxlag'  => array(
 590                                 ApiBase::PARAM_TYPE => 'integer'
 591                         ),
 592                         'smaxage' => array(
 593                                 ApiBase::PARAM_TYPE => 'integer',
 594                                 ApiBase::PARAM_DFLT => 0
 595                         ),
 596                         'maxage' => array(
 597                                 ApiBase::PARAM_TYPE => 'integer',
 598                                 ApiBase::PARAM_DFLT => 0
 599                         ),
 600                         'requestid' => null,
 601                 );
 602         }
 603
 604         /**
 605          * See ApiBase for description.
 606          */
 607         public function getParamDescription() {
 608                 return array(
 609                         'format' => 'The format of the output',
 610                         'action' => 'What action you would like to perform',
 611                         'version' => 'When showing help, include version for each module',
 612                         'maxlag' => 'Maximum lag',
 613                         'smaxage' => 'Set the s-maxage header to this many seconds. Errors are never cached',
 614                         'maxage' => 'Set the max-age header to this many seconds. Errors are never cached',
 615                         'requestid' => 'Request ID to distinguish requests. This will just be output back to you',
 616                 );
 617         }
 618
 619         /**
 620          * See ApiBase for description.
 621          */
 622         public function getDescription() {
 623                 return array(
 624                         '',
 625                         '',
 626                         '******************************************************************',
 627                         '**                                                              **',
 628                         '**  This is an auto-generated MediaWiki API documentation page  **',
 629                         '**                                                              **',
 630                         '**                  Documentation and Examples:                 **',
 631                         '**               http://www.mediawiki.org/wiki/API              **',
 632                         '**                                                              **',
 633                         '******************************************************************',
 634                         '',
 635                         'Status:          All features shown on this page should be working, but the API',
 636                         '                 is still in active development, and  may change at any time.',
 637                         '                 Make sure to monitor our mailing list for any updates.',
 638                         '',
 639                         'Documentation:   http://www.mediawiki.org/wiki/API',
 640                         'Mailing list:    http://lists.wikimedia.org/mailman/listinfo/mediawiki-api',
 641                         'Api Announcements:    http://lists.wikimedia.org/mailman/listinfo/mediawiki-api-announce',
 642                         'Bugs & Requests: http://bugzilla.wikimedia.org/buglist.cgi?component=API&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&order=bugs.delta_ts',
 643                         '',
 644                         '',
 645                         '',
 646                         '',
 647                         '',
 648                 );
 649         }
 650
 651         public function getPossibleErrors() {
 652                 return array_merge( parent::getPossibleErrors(), array(
 653                         array( 'readonlytext' ),
 654                         array( 'code' => 'unknown_format', 'info' => 'Unrecognized format: format' ),
 655                         array( 'code' => 'unknown_action', 'info' => 'The API requires a valid action parameter' ),
 656                         array( 'code' => 'maxlag', 'info' => 'Waiting for host: x seconds lagged' ),
 657                         array( 'code' => 'maxlag', 'info' => 'Waiting for a database server: x seconds lagged' ),
 658                 ) );
 659         }
 660
 661         /**
 662          * Returns an array of strings with credits for the API
 663          */
 664         protected function getCredits() {
 665                 return array(
 666                         'API developers:',
 667                         '    Roan Kattouw <Firstname>.<Lastname>@home.nl (lead developer Sep 2007-present)',
 668                         '    Victor Vasiliev - vasilvv at gee mail dot com',
 669                         '    Bryan Tong Minh - bryan . tongminh @ gmail . com',
 670                         '    Sam Reed - sam @ reedyboy . net',
 671                         '    Yuri Astrakhan <Firstname><Lastname>@gmail.com (creator, lead developer Sep 2006-Sep 2007)',
 672                         '',
 673                         'Please send your comments, suggestions and questions to mediawiki-api@lists.wikimedia.org',
 674                         'or file a bug report at http://bugzilla.wikimedia.org/'
 675                 );
 676         }
 677
 678         /**
 679          * Override the parent to generate help messages for all available modules.
 680          */
 681         public function makeHelpMsg() {
 682                 global $wgMemc, $wgAPICacheHelp, $wgAPICacheHelpTimeout;
 683                 $this->mPrinter->setHelp();
 684                 // Get help text from cache if present
 685                 $key = wfMemcKey( 'apihelp', $this->getModuleName(),
 686                         SpecialVersion::getVersion( 'nodb' ) .
 687                         $this->getMain()->getShowVersions() );
 688                 if ( $wgAPICacheHelp ) {
 689                         $cached = $wgMemc->get( $key );
 690                         if ( $cached ) {
 691                                 return $cached;
 692                         }
 693                 }
 694                 $retval = $this->reallyMakeHelpMsg();
 695                 if ( $wgAPICacheHelp ) {
 696                         $wgMemc->set( $key, $retval, $wgAPICacheHelpTimeout );
 697                 }
 698                 return $retval;
 699         }
 700
 701         public function reallyMakeHelpMsg() {
 702                 $this->mPrinter->setHelp();
 703
 704                 // Use parent to make default message for the main module
 705                 $msg = parent::makeHelpMsg();
 706
 707                 $astriks = str_repeat( '*** ', 10 );
 708                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
 709                 foreach ( $this->mModules as $moduleName => $unused ) {
 710                         $module = new $this->mModules[$moduleName] ( $this, $moduleName );
 711                         $msg .= self::makeHelpMsgHeader( $module, 'action' );
 712                         $msg2 = $module->makeHelpMsg();
 713                         if ( $msg2 !== false ) {
 714                                 $msg .= $msg2;
 715                         }
 716                         $msg .= "\n";
 717                 }
 718
 719                 $msg .= "\n$astriks Permissions $astriks\n\n";
 720                 foreach ( self::$mRights as $right => $rightMsg ) {
 721                         $groups = User::getGroupsWithPermission( $right );
 722                         $msg .= "* " . $right . " *\n  " . wfMsgReplaceArgs( $rightMsg[ 'msg' ], $rightMsg[ 'params' ] ) .
 723                                                 "\nGranted to:\n  " . str_replace( '*', 'all', implode( ', ', $groups ) ) . "\n";
 724
 725                 }
 726
 727                 $msg .= "\n$astriks Formats  $astriks\n\n";
 728                 foreach ( $this->mFormats as $formatName => $unused ) {
 729                         $module = $this->createPrinterByName( $formatName );
 730                         $msg .= self::makeHelpMsgHeader( $module, 'format' );
 731                         $msg2 = $module->makeHelpMsg();
 732                         if ( $msg2 !== false ) {
 733                                 $msg .= $msg2;
 734                         }
 735                         $msg .= "\n";
 736                 }
 737
 738                 $msg .= "\n*** Credits: ***\n   " . implode( "\n   ", $this->getCredits() ) . "\n";
 739
 740
 741                 return $msg;
 742         }
 743
 744         public static function makeHelpMsgHeader( $module, $paramName ) {
 745                 $modulePrefix = $module->getModulePrefix();
 746                 if ( strval( $modulePrefix ) !== '' ) {
 747                         $modulePrefix = "($modulePrefix) ";
 748                 }
 749
 750                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
 751         }
 752
 753         private $mIsBot = null;
 754         private $mIsSysop = null;
 755         private $mCanApiHighLimits = null;
 756
 757         /**
 758          * Returns true if the currently logged in user is a bot, false otherwise
 759          * OBSOLETE, use canApiHighLimits() instead
 760          */
 761         public function isBot() {
 762                 if ( !isset( $this->mIsBot ) ) {
 763                         global $wgUser;
 764                         $this->mIsBot = $wgUser->isAllowed( 'bot' );
 765                 }
 766                 return $this->mIsBot;
 767         }
 768
 769         /**
 770          * Similar to isBot(), this method returns true if the logged in user is
 771          * a sysop, and false if not.
 772          * OBSOLETE, use canApiHighLimits() instead
 773          */
 774         public function isSysop() {
 775                 if ( !isset( $this->mIsSysop ) ) {
 776                         global $wgUser;
 777                         $this->mIsSysop = in_array( 'sysop', $wgUser->getGroups() );
 778                 }
 779
 780                 return $this->mIsSysop;
 781         }
 782
 783         /**
 784          * Check whether the current user is allowed to use high limits
 785          * @return bool
 786          */
 787         public function canApiHighLimits() {
 788                 if ( !isset( $this->mCanApiHighLimits ) ) {
 789                         global $wgUser;
 790                         $this->mCanApiHighLimits = $wgUser->isAllowed( 'apihighlimits' );
 791                 }
 792
 793                 return $this->mCanApiHighLimits;
 794         }
 795
 796         /**
 797          * Check whether the user wants us to show version information in the API help
 798          * @return bool
 799          */
 800         public function getShowVersions() {
 801                 return $this->mShowVersions;
 802         }
 803
 804         /**
 805          * Returns the version information of this file, plus it includes
 806          * the versions for all files that are not callable proper API modules
 807          */
 808         public function getVersion() {
 809                 $vers = array ();
 810                 $vers[] = 'MediaWiki: ' . SpecialVersion::getVersion() . "\n    http://svn.wikimedia.org/viewvc/mediawiki/trunk/phase3/";
 811                 $vers[] = __CLASS__ . ': $Id$';
 812                 $vers[] = ApiBase::getBaseVersion();
 813                 $vers[] = ApiFormatBase::getBaseVersion();
 814                 $vers[] = ApiQueryBase::getBaseVersion();
 815                 return $vers;
 816         }
 817
 818         /**
 819          * Add or overwrite a module in this ApiMain instance. Intended for use by extending
 820          * classes who wish to add their own modules to their lexicon or override the
 821          * behavior of inherent ones.
 822          *
 823          * @param $mdlName String The identifier for this module.
 824          * @param $mdlClass String The class where this module is implemented.
 825          */
 826         protected function addModule( $mdlName, $mdlClass ) {
 827                 $this->mModules[$mdlName] = $mdlClass;
 828         }
 829
 830         /**
 831          * Add or overwrite an output format for this ApiMain. Intended for use by extending
 832          * classes who wish to add to or modify current formatters.
 833          *
 834          * @param $fmtName The identifier for this format.
 835          * @param $fmtClass The class implementing this format.
 836          */
 837         protected function addFormat( $fmtName, $fmtClass ) {
 838                 $this->mFormats[$fmtName] = $fmtClass;
 839         }
 840
 841         /**
 842          * Get the array mapping module names to class names
 843          */
 844         function getModules() {
 845                 return $this->mModules;
 846         }
 847 }
 848
 849 /**
 850  * This exception will be thrown when dieUsage is called to stop module execution.
 851  * The exception handling code will print a help screen explaining how this API may be used.
 852  *
 853  * @ingroup API
 854  */
 855 class UsageException extends Exception {
 856
 857         private $mCodestr;
 858         private $mExtraData;
 859
 860         public function __construct( $message, $codestr, $code = 0, $extradata = null ) {
 861                 parent::__construct( $message, $code );
 862                 $this->mCodestr = $codestr;
 863                 $this->mExtraData = $extradata;
 864         }
 865
 866         public function getCodeString() {
 867                 return $this->mCodestr;
 868         }
 869
 870         public function getMessageArray() {
 871                 $result = array(
 872                         'code' => $this->mCodestr,
 873                         'info' => $this->getMessage()
 874                 );
 875                 if ( is_array( $this->mExtraData ) ) {
 876                         $result = array_merge( $result, $this->mExtraData );
 877                 }
 878                 return $result;
 879         }
 880
 881         public function __toString() {
 882                 return "{$this->getCodeString()}: {$this->getMessage()}";
 883         }
 884 }