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 if ( !defined( 'MEDIAWIKI' ) ) {
  29         // Eclipse helper - will be ignored in production
  30         require_once( 'ApiBase.php' );
  31 }
  32
  33 /**
  34  * This is the main API class, used for both external and internal processing.
  35  * When executed, it will create the requested formatter object,
  36  * instantiate and execute an object associated with the needed action,
  37  * and use formatter to print results.
  38  * In case of an exception, an error message will be printed using the same formatter.
  39  *
  40  * To use API from another application, run it using FauxRequest object, in which
  41  * case any internal exceptions will not be handled but passed up to the caller.
  42  * After successful execution, use getResult() for the resulting data.
  43  *
  44  * @ingroup API
  45  */
  46 class ApiMain extends ApiBase {
  47
  48         /**
  49          * When no format parameter is given, this format will be used
  50          */
  51         const API_DEFAULT_FORMAT = 'xmlfm';
  52
  53         /**
  54          * List of available modules: action name => module class
  55          */
  56         private static $Modules = array(
  57                 'login' => 'ApiLogin',
  58                 'logout' => 'ApiLogout',
  59                 'query' => 'ApiQuery',
  60                 'expandtemplates' => 'ApiExpandTemplates',
  61                 'parse' => 'ApiParse',
  62                 'opensearch' => 'ApiOpenSearch',
  63                 'feedwatchlist' => 'ApiFeedWatchlist',
  64                 'help' => 'ApiHelp',
  65                 'paraminfo' => 'ApiParamInfo',
  66                 'rsd' => 'ApiRsd',
  67                 'compare' => 'ApiComparePages',
  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                 'upload' => 'ApiUpload',
  80                 'filerevert' => 'ApiFileRevert',
  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                 'dump' => 'ApiFormatDump',
 108                 'dumpfm' => 'ApiFormatDump',
 109         );
 110
 111         /**
 112          * List of user roles that are specifically relevant to the API.
 113          * array( 'right' => array ( 'msg'    => 'Some message with a $1',
 114          *                           'params' => array ( $someVarToSubst ) ),
 115          *                          );
 116          */
 117         private static $mRights = array(
 118                 'writeapi' => array(
 119                         'msg' => 'Use of the write API',
 120                         'params' => array()
 121                 ),
 122                 'apihighlimits' => array(
 123                         '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.',
 124                         'params' => array( ApiBase::LIMIT_SML2, ApiBase::LIMIT_BIG2 )
 125                 )
 126         );
 127
 128         /**
 129          * @var ApiFormatBase
 130          */
 131         private $mPrinter;
 132
 133         private $mModules, $mModuleNames, $mFormats, $mFormatNames;
 134         private $mResult, $mAction, $mShowVersions, $mEnableWrite, $mRequest;
 135         private $mInternalMode, $mSquidMaxage, $mModule;
 136
 137         private $mCacheMode = 'private';
 138         private $mCacheControl = array();
 139
 140         /**
 141          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 142          *
 143          * @param $request WebRequest - if this is an instance of FauxRequest, errors are thrown and no printing occurs
 144          * @param $enableWrite bool should be set to true if the api may modify data
 145          */
 146         public function __construct( $request, $enableWrite = false ) {
 147                 $this->mInternalMode = ( $request instanceof FauxRequest );
 148
 149                 // Special handling for the main module: $parent === $this
 150                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 151
 152                 if ( !$this->mInternalMode ) {
 153                         // Impose module restrictions.
 154                         // If the current user cannot read,
 155                         // Remove all modules other than login
 156                         global $wgUser;
 157
 158                         if ( $request->getVal( 'callback' ) !== null ) {
 159                                 // JSON callback allows cross-site reads.
 160                                 // For safety, strip user credentials.
 161                                 wfDebug( "API: stripping user credentials for JSON callback\n" );
 162                                 $wgUser = new User();
 163                         }
 164                 }
 165
 166                 global $wgAPIModules; // extension modules
 167                 $this->mModules = $wgAPIModules + self::$Modules;
 168
 169                 $this->mModuleNames = array_keys( $this->mModules );
 170                 $this->mFormats = self::$Formats;
 171                 $this->mFormatNames = array_keys( $this->mFormats );
 172
 173                 $this->mResult = new ApiResult( $this );
 174                 $this->mShowVersions = false;
 175                 $this->mEnableWrite = $enableWrite;
 176
 177                 $this->mRequest = &$request;
 178
 179                 $this->mSquidMaxage = - 1; // flag for executeActionWithErrorHandling()
 180                 $this->mCommit = false;
 181         }
 182
 183         /**
 184          * Return true if the API was started by other PHP code using FauxRequest
 185          * @return bool
 186          */
 187         public function isInternalMode() {
 188                 return $this->mInternalMode;
 189         }
 190
 191         /**
 192          * Return the request object that contains client's request
 193          * @return WebRequest
 194          */
 195         public function getRequest() {
 196                 return $this->mRequest;
 197         }
 198
 199         /**
 200          * Get the ApiResult object associated with current request
 201          *
 202          * @return ApiResult
 203          */
 204         public function getResult() {
 205                 return $this->mResult;
 206         }
 207
 208         /**
 209          * Get the API module object. Only works after executeAction()
 210          *
 211          * @return ApiBase
 212          */
 213         public function getModule() {
 214                 return $this->mModule;
 215         }
 216
 217         /**
 218          * Get the result formatter object. Only works after setupExecuteAction()
 219          *
 220          * @return ApiFormatBase
 221          */
 222         public function getPrinter() {
 223                 return $this->mPrinter;
 224         }
 225
 226         /**
 227          * Set how long the response should be cached.
 228          */
 229         public function setCacheMaxAge( $maxage ) {
 230                 $this->setCacheControl( array(
 231                         'max-age' => $maxage,
 232                         's-maxage' => $maxage
 233                 ) );
 234         }
 235
 236         /**
 237          * Set the type of caching headers which will be sent.
 238          *
 239          * @param $mode String One of:
 240          *    - 'public':     Cache this object in public caches, if the maxage or smaxage
 241          *         parameter is set, or if setCacheMaxAge() was called. If a maximum age is
 242          *         not provided by any of these means, the object will be private.
 243          *    - 'private':    Cache this object only in private client-side caches.
 244          *    - 'anon-public-user-private': Make this object cacheable for logged-out
 245          *         users, but private for logged-in users. IMPORTANT: If this is set, it must be
 246          *         set consistently for a given URL, it cannot be set differently depending on
 247          *         things like the contents of the database, or whether the user is logged in.
 248          *
 249          *  If the wiki does not allow anonymous users to read it, the mode set here
 250          *  will be ignored, and private caching headers will always be sent. In other words,
 251          *  the "public" mode is equivalent to saying that the data sent is as public as a page
 252          *  view.
 253          *
 254          *  For user-dependent data, the private mode should generally be used. The
 255          *  anon-public-user-private mode should only be used where there is a particularly
 256          *  good performance reason for caching the anonymous response, but where the
 257          *  response to logged-in users may differ, or may contain private data.
 258          *
 259          *  If this function is never called, then the default will be the private mode.
 260          */
 261         public function setCacheMode( $mode ) {
 262                 if ( !in_array( $mode, array( 'private', 'public', 'anon-public-user-private' ) ) ) {
 263                         wfDebug( __METHOD__ . ": unrecognised cache mode \"$mode\"\n" );
 264                         // Ignore for forwards-compatibility
 265                         return;
 266                 }
 267
 268                 if ( !in_array( 'read', User::getGroupPermissions( array( '*' ) ), true ) ) {
 269                         // Private wiki, only private headers
 270                         if ( $mode !== 'private' ) {
 271                                 wfDebug( __METHOD__ . ": ignoring request for $mode cache mode, private wiki\n" );
 272                                 return;
 273                         }
 274                 }
 275
 276                 wfDebug( __METHOD__ . ": setting cache mode $mode\n" );
 277                 $this->mCacheMode = $mode;
 278         }
 279
 280         /**
 281          * @deprecated since 1.17 Private caching is now the default, so there is usually no
 282          * need to call this function. If there is a need, you can use
 283          * $this->setCacheMode('private')
 284          */
 285         public function setCachePrivate() {
 286                 $this->setCacheMode( 'private' );
 287         }
 288
 289         /**
 290          * Set directives (key/value pairs) for the Cache-Control header.
 291          * Boolean values will be formatted as such, by including or omitting
 292          * without an equals sign.
 293          *
 294          * Cache control values set here will only be used if the cache mode is not
 295          * private, see setCacheMode().
 296          */
 297         public function setCacheControl( $directives ) {
 298                 $this->mCacheControl = $directives + $this->mCacheControl;
 299         }
 300
 301         /**
 302          * Make sure Vary: Cookie and friends are set. Use this when the output of a request
 303          * may be cached for anons but may not be cached for logged-in users.
 304          *
 305          * WARNING: This function must be called CONSISTENTLY for a given URL. This means that a
 306          * given URL must either always or never call this function; if it sometimes does and
 307          * sometimes doesn't, stuff will break.
 308          *
 309          * @deprecated since 1.17 Use setCacheMode( 'anon-public-user-private' )
 310          */
 311         public function setVaryCookie() {
 312                 $this->setCacheMode( 'anon-public-user-private' );
 313         }
 314
 315         /**
 316          * Create an instance of an output formatter by its name
 317          *
 318          * @return ApiFormatBase
 319          */
 320         public function createPrinterByName( $format ) {
 321                 if ( !isset( $this->mFormats[$format] ) ) {
 322                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 323                 }
 324                 return new $this->mFormats[$format] ( $this, $format );
 325         }
 326
 327         /**
 328          * Execute api request. Any errors will be handled if the API was called by the remote client.
 329          */
 330         public function execute() {
 331                 $this->profileIn();
 332                 if ( $this->mInternalMode ) {
 333                         $this->executeAction();
 334                 } else {
 335                         $this->executeActionWithErrorHandling();
 336                 }
 337
 338                 $this->profileOut();
 339         }
 340
 341         /**
 342          * Execute an action, and in case of an error, erase whatever partial results
 343          * have been accumulated, and replace it with an error message and a help screen.
 344          */
 345         protected function executeActionWithErrorHandling() {
 346                 // In case an error occurs during data output,
 347                 // clear the output buffer and print just the error information
 348                 ob_start();
 349
 350                 try {
 351                         $this->executeAction();
 352                 } catch ( Exception $e ) {
 353                         // Log it
 354                         if ( $e instanceof MWException ) {
 355                                 wfDebugLog( 'exception', $e->getLogMessage() );
 356                         }
 357
 358                         //
 359                         // Handle any kind of exception by outputing properly formatted error message.
 360                         // If this fails, an unhandled exception should be thrown so that global error
 361                         // handler will process and log it.
 362                         //
 363
 364                         $errCode = $this->substituteResultWithError( $e );
 365
 366                         // Error results should not be cached
 367                         $this->setCacheMode( 'private' );
 368
 369                         $headerStr = 'MediaWiki-API-Error: ' . $errCode;
 370                         if ( $e->getCode() === 0 ) {
 371                                 header( $headerStr );
 372                         } else {
 373                                 header( $headerStr, true, $e->getCode() );
 374                         }
 375
 376                         // Reset and print just the error message
 377                         ob_clean();
 378
 379                         // If the error occured during printing, do a printer->profileOut()
 380                         $this->mPrinter->safeProfileOut();
 381                         $this->printResult( true );
 382                 }
 383
 384                 // Send cache headers after any code which might generate an error, to
 385                 // avoid sending public cache headers for errors.
 386                 $this->sendCacheHeaders();
 387
 388                 if ( $this->mPrinter->getIsHtml() && !$this->mPrinter->isDisabled() ) {
 389                         echo wfReportTime();
 390                 }
 391
 392                 ob_end_flush();
 393         }
 394
 395         protected function sendCacheHeaders() {
 396                 if ( $this->mCacheMode == 'private' ) {
 397                         header( 'Cache-Control: private' );
 398                         return;
 399                 }
 400
 401                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 402                         global $wgUseXVO, $wgOut;
 403                         header( 'Vary: Accept-Encoding, Cookie' );
 404                         if ( $wgUseXVO ) {
 405                                 header( $wgOut->getXVO() );
 406                                 if ( $wgOut->haveCacheVaryCookies() ) {
 407                                         // Logged in, mark this request private
 408                                         header( 'Cache-Control: private' );
 409                                         return;
 410                                 }
 411                                 // Logged out, send normal public headers below
 412                         } elseif ( session_id() != '' ) {
 413                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 414                                 // Mark request private
 415                                 header( 'Cache-Control: private' );
 416                                 return;
 417                         } // else no XVO and anonymous, send public headers below
 418                 }
 419
 420                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 421                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 422                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 423                 }
 424                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 425                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 426                 }
 427
 428                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 429                         // Public cache not requested
 430                         // Sending a Vary header in this case is harmless, and protects us
 431                         // against conditional calls of setCacheMaxAge().
 432                         header( 'Cache-Control: private' );
 433                         return;
 434                 }
 435
 436                 $this->mCacheControl['public'] = true;
 437
 438                 // Send an Expires header
 439                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 440                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 441                 header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 442
 443                 // Construct the Cache-Control header
 444                 $ccHeader = '';
 445                 $separator = '';
 446                 foreach ( $this->mCacheControl as $name => $value ) {
 447                         if ( is_bool( $value ) ) {
 448                                 if ( $value ) {
 449                                         $ccHeader .= $separator . $name;
 450                                         $separator = ', ';
 451                                 }
 452                         } else {
 453                                 $ccHeader .= $separator . "$name=$value";
 454                                 $separator = ', ';
 455                         }
 456                 }
 457
 458                 header( "Cache-Control: $ccHeader" );
 459         }
 460
 461         /**
 462          * Replace the result data with the information about an exception.
 463          * Returns the error code
 464          * @param $e Exception
 465          * @return string
 466          */
 467         protected function substituteResultWithError( $e ) {
 468                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 469                 if ( !isset ( $this->mPrinter ) ) {
 470                         // The printer has not been created yet. Try to manually get formatter value.
 471                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 472                         if ( !in_array( $value, $this->mFormatNames ) ) {
 473                                 $value = self::API_DEFAULT_FORMAT;
 474                         }
 475
 476                         $this->mPrinter = $this->createPrinterByName( $value );
 477                         if ( $this->mPrinter->getNeedsRawData() ) {
 478                                 $this->getResult()->setRawMode();
 479                         }
 480                 }
 481
 482                 if ( $e instanceof UsageException ) {
 483                         // User entered incorrect parameters - print usage screen
 484                         $errMessage = $e->getMessageArray();
 485
 486                         // Only print the help message when this is for the developer, not runtime
 487                         if ( $this->mPrinter->getWantsHelp() || $this->mAction == 'help' ) {
 488                                 ApiResult::setContent( $errMessage, $this->makeHelpMsg() );
 489                         }
 490
 491                 } else {
 492                         global $wgShowSQLErrors, $wgShowExceptionDetails;
 493                         // Something is seriously wrong
 494                         if ( ( $e instanceof DBQueryError ) && !$wgShowSQLErrors ) {
 495                                 $info = 'Database query error';
 496                         } else {
 497                                 $info = "Exception Caught: {$e->getMessage()}";
 498                         }
 499
 500                         $errMessage = array(
 501                                 'code' => 'internal_api_error_' . get_class( $e ),
 502                                 'info' => $info,
 503                         );
 504                         ApiResult::setContent( $errMessage, $wgShowExceptionDetails ? "\n\n{$e->getTraceAsString()}\n\n" : '' );
 505                 }
 506
 507                 $this->getResult()->reset();
 508                 $this->getResult()->disableSizeCheck();
 509                 // Re-add the id
 510                 $requestid = $this->getParameter( 'requestid' );
 511                 if ( !is_null( $requestid ) ) {
 512                         $this->getResult()->addValue( null, 'requestid', $requestid );
 513                 }
 514                 // servedby is especially useful when debugging errors
 515                 $this->getResult()->addValue( null, 'servedby', wfHostName() );
 516                 $this->getResult()->addValue( null, 'error', $errMessage );
 517
 518                 return $errMessage['code'];
 519         }
 520
 521         /**
 522          * Set up for the execution.
 523          * @return array
 524          */
 525         protected function setupExecuteAction() {
 526                 // First add the id to the top element
 527                 $requestid = $this->getParameter( 'requestid' );
 528                 if ( !is_null( $requestid ) ) {
 529                         $this->getResult()->addValue( null, 'requestid', $requestid );
 530                 }
 531                 $servedby = $this->getParameter( 'servedby' );
 532                 if ( $servedby ) {
 533                         $this->getResult()->addValue( null, 'servedby', wfHostName() );
 534                 }
 535
 536                 $params = $this->extractRequestParams();
 537
 538                 $this->mShowVersions = $params['version'];
 539                 $this->mAction = $params['action'];
 540
 541                 if ( !is_string( $this->mAction ) ) {
 542                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 543                 }
 544
 545                 return $params;
 546         }
 547
 548         /**
 549          * Set up the module for response
 550          * @return ApiBase The module that will handle this action
 551          */
 552         protected function setupModule() {
 553                 // Instantiate the module requested by the user
 554                 $module = new $this->mModules[$this->mAction] ( $this, $this->mAction );
 555                 $this->mModule = $module;
 556
 557                 $moduleParams = $module->extractRequestParams();
 558
 559                 // Die if token required, but not provided (unless there is a gettoken parameter)
 560                 $salt = $module->getTokenSalt();
 561                 if ( $salt !== false && !isset( $moduleParams['gettoken'] ) ) {
 562                         if ( !isset( $moduleParams['token'] ) ) {
 563                                 $this->dieUsageMsg( array( 'missingparam', 'token' ) );
 564                         } else {
 565                                 global $wgUser;
 566                                 if ( !$wgUser->matchEditToken( $moduleParams['token'], $salt, $this->getMain()->getRequest() ) ) {
 567                                         $this->dieUsageMsg( array( 'sessionfailure' ) );
 568                                 }
 569                         }
 570                 }
 571                 return $module;
 572         }
 573
 574         /**
 575          * Check the max lag if necessary
 576          * @param $module ApiBase object: Api module being used
 577          * @param $params Array an array containing the request parameters.
 578          * @return boolean True on success, false should exit immediately
 579          */
 580         protected function checkMaxLag( $module, $params ) {
 581                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
 582                         // Check for maxlag
 583                         global $wgShowHostnames;
 584                         $maxLag = $params['maxlag'];
 585                         list( $host, $lag ) = wfGetLB()->getMaxLag();
 586                         if ( $lag > $maxLag ) {
 587                                 header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
 588                                 header( 'X-Database-Lag: ' . intval( $lag ) );
 589                                 if ( $wgShowHostnames ) {
 590                                         $this->dieUsage( "Waiting for $host: $lag seconds lagged", 'maxlag' );
 591                                 } else {
 592                                         $this->dieUsage( "Waiting for a database server: $lag seconds lagged", 'maxlag' );
 593                                 }
 594                                 return false;
 595                         }
 596                 }
 597                 return true;
 598         }
 599
 600
 601         /**
 602          * Check for sufficient permissions to execute
 603          * @param $module ApiBase An Api module
 604          */
 605         protected function checkExecutePermissions( $module ) {
 606                 global $wgUser;
 607                 if ( $module->isReadMode() && !in_array( 'read', User::getGroupPermissions( array( '*' ) ), true ) &&
 608                         !$wgUser->isAllowed( 'read' ) )
 609                 {
 610                         $this->dieUsageMsg( array( 'readrequired' ) );
 611                 }
 612                 if ( $module->isWriteMode() ) {
 613                         if ( !$this->mEnableWrite ) {
 614                                 $this->dieUsageMsg( array( 'writedisabled' ) );
 615                         }
 616                         if ( !$wgUser->isAllowed( 'writeapi' ) ) {
 617                                 $this->dieUsageMsg( array( 'writerequired' ) );
 618                         }
 619                         if ( wfReadOnly() ) {
 620                                 $this->dieReadOnly();
 621                         }
 622                 }
 623         }
 624
 625         /**
 626          * Check POST for external response and setup result printer
 627          * @param $module ApiBase An Api module
 628          * @param $params Array an array with the request parameters
 629          */
 630         protected function setupExternalResponse( $module, $params ) {
 631                 // Ignore mustBePosted() for internal calls
 632                 if ( $module->mustBePosted() && !$this->mRequest->wasPosted() ) {
 633                         $this->dieUsageMsg( array( 'mustbeposted', $this->mAction ) );
 634                 }
 635
 636                 // See if custom printer is used
 637                 $this->mPrinter = $module->getCustomPrinter();
 638                 if ( is_null( $this->mPrinter ) ) {
 639                         // Create an appropriate printer
 640                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
 641                 }
 642
 643                 if ( $this->mPrinter->getNeedsRawData() ) {
 644                         $this->getResult()->setRawMode();
 645                 }
 646         }
 647
 648         /**
 649          * Execute the actual module, without any error handling
 650          */
 651         protected function executeAction() {
 652                 $params = $this->setupExecuteAction();
 653                 $module = $this->setupModule();
 654
 655                 $this->checkExecutePermissions( $module );
 656
 657                 if ( !$this->checkMaxLag( $module, $params ) ) {
 658                         return;
 659                 }
 660
 661                 if ( !$this->mInternalMode ) {
 662                         $this->setupExternalResponse( $module, $params );
 663                 }
 664
 665                 // Execute
 666                 $module->profileIn();
 667                 $module->execute();
 668                 wfRunHooks( 'APIAfterExecute', array( &$module ) );
 669                 $module->profileOut();
 670
 671                 if ( !$this->mInternalMode ) {
 672                         // Print result data
 673                         $this->printResult( false );
 674                 }
 675         }
 676
 677         /**
 678          * Print results using the current printer
 679          */
 680         protected function printResult( $isError ) {
 681                 $this->getResult()->cleanUpUTF8();
 682                 $printer = $this->mPrinter;
 683                 $printer->profileIn();
 684
 685                 /**
 686                  * If the help message is requested in the default (xmlfm) format,
 687                  * tell the printer not to escape ampersands so that our links do
 688                  * not break.
 689                  */
 690                 $printer->setUnescapeAmps( ( $this->mAction == 'help' || $isError )
 691                                 && $printer->getFormat() == 'XML' && $printer->getIsHtml() );
 692
 693                 $printer->initPrinter( $isError );
 694
 695                 $printer->execute();
 696                 $printer->closePrinter();
 697                 $printer->profileOut();
 698         }
 699
 700         /**
 701          * @return bool
 702          */
 703         public function isReadMode() {
 704                 return false;
 705         }
 706
 707         /**
 708          * See ApiBase for description.
 709          */
 710         public function getAllowedParams() {
 711                 return array(
 712                         'format' => array(
 713                                 ApiBase::PARAM_DFLT => ApiMain::API_DEFAULT_FORMAT,
 714                                 ApiBase::PARAM_TYPE => $this->mFormatNames
 715                         ),
 716                         'action' => array(
 717                                 ApiBase::PARAM_DFLT => 'help',
 718                                 ApiBase::PARAM_TYPE => $this->mModuleNames
 719                         ),
 720                         'version' => false,
 721                         'maxlag'  => array(
 722                                 ApiBase::PARAM_TYPE => 'integer'
 723                         ),
 724                         'smaxage' => array(
 725                                 ApiBase::PARAM_TYPE => 'integer',
 726                                 ApiBase::PARAM_DFLT => 0
 727                         ),
 728                         'maxage' => array(
 729                                 ApiBase::PARAM_TYPE => 'integer',
 730                                 ApiBase::PARAM_DFLT => 0
 731                         ),
 732                         'requestid' => null,
 733                         'servedby'  => false,
 734                 );
 735         }
 736
 737         /**
 738          * See ApiBase for description.
 739          */
 740         public function getParamDescription() {
 741                 return array(
 742                         'format' => 'The format of the output',
 743                         'action' => 'What action you would like to perform. See below for module help',
 744                         'version' => 'When showing help, include version for each module',
 745                         'maxlag' => 'Maximum lag',
 746                         'smaxage' => 'Set the s-maxage header to this many seconds. Errors are never cached',
 747                         'maxage' => 'Set the max-age header to this many seconds. Errors are never cached',
 748                         'requestid' => 'Request ID to distinguish requests. This will just be output back to you',
 749                         'servedby' => 'Include the hostname that served the request in the results. Unconditionally shown on error',
 750                 );
 751         }
 752
 753         /**
 754          * See ApiBase for description.
 755          */
 756         public function getDescription() {
 757                 return array(
 758                         '',
 759                         '',
 760                         '**********************************************************************************************************',
 761                         '**                                                                                                      **',
 762                         '**                      This is an auto-generated MediaWiki API documentation page                      **',
 763                         '**                                                                                                      **',
 764                         '**                                    Documentation and Examples:                                       **',
 765                         '**                                 http://www.mediawiki.org/wiki/API                                    **',
 766                         '**                                                                                                      **',
 767                         '**********************************************************************************************************',
 768                         '',
 769                         'Status:                All features shown on this page should be working, but the API',
 770                         '                       is still in active development, and  may change at any time.',
 771                         '                       Make sure to monitor our mailing list for any updates',
 772                         '',
 773                         'Documentation:         http://www.mediawiki.org/wiki/API',
 774                         'Mailing list:          http://lists.wikimedia.org/mailman/listinfo/mediawiki-api',
 775                         'Api Announcements:     http://lists.wikimedia.org/mailman/listinfo/mediawiki-api-announce',
 776                         'Bugs & Requests:       http://bugzilla.wikimedia.org/buglist.cgi?component=API&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&order=bugs.delta_ts',
 777                         '',
 778                         '',
 779                         '',
 780                         '',
 781                         '',
 782                 );
 783         }
 784
 785         public function getPossibleErrors() {
 786                 return array_merge( parent::getPossibleErrors(), array(
 787                         array( 'readonlytext' ),
 788                         array( 'code' => 'unknown_format', 'info' => 'Unrecognized format: format' ),
 789                         array( 'code' => 'unknown_action', 'info' => 'The API requires a valid action parameter' ),
 790                         array( 'code' => 'maxlag', 'info' => 'Waiting for host: x seconds lagged' ),
 791                         array( 'code' => 'maxlag', 'info' => 'Waiting for a database server: x seconds lagged' ),
 792                 ) );
 793         }
 794
 795         /**
 796          * Returns an array of strings with credits for the API
 797          */
 798         protected function getCredits() {
 799                 return array(
 800                         'API developers:',
 801                         '    Roan Kattouw <Firstname>.<Lastname>@gmail.com (lead developer Sep 2007-present)',
 802                         '    Victor Vasiliev - vasilvv at gee mail dot com',
 803                         '    Bryan Tong Minh - bryan . tongminh @ gmail . com',
 804                         '    Sam Reed - sam @ reedyboy . net',
 805                         '    Yuri Astrakhan <Firstname><Lastname>@gmail.com (creator, lead developer Sep 2006-Sep 2007)',
 806                         '',
 807                         'Please send your comments, suggestions and questions to mediawiki-api@lists.wikimedia.org',
 808                         'or file a bug report at http://bugzilla.wikimedia.org/'
 809                 );
 810         }
 811         /**
 812          * Sets whether the pretty-printer should format *bold* and $italics$
 813          */
 814         public function setHelp( $help = true ) {
 815                 $this->mPrinter->setHelp( $help );
 816         }
 817
 818         /**
 819          * Override the parent to generate help messages for all available modules.
 820          */
 821         public function makeHelpMsg() {
 822                 global $wgMemc, $wgAPICacheHelpTimeout;
 823                 $this->setHelp();
 824                 // Get help text from cache if present
 825                 $key = wfMemcKey( 'apihelp', $this->getModuleName(),
 826                         SpecialVersion::getVersion( 'nodb' ) .
 827                         $this->getMain()->getShowVersions() );
 828                 if ( $wgAPICacheHelpTimeout > 0 ) {
 829                         $cached = $wgMemc->get( $key );
 830                         if ( $cached ) {
 831                                 return $cached;
 832                         }
 833                 }
 834                 $retval = $this->reallyMakeHelpMsg();
 835                 if ( $wgAPICacheHelpTimeout > 0 ) {
 836                         $wgMemc->set( $key, $retval, $wgAPICacheHelpTimeout );
 837                 }
 838                 return $retval;
 839         }
 840
 841         public function reallyMakeHelpMsg() {
 842                 $this->setHelp();
 843
 844                 // Use parent to make default message for the main module
 845                 $msg = parent::makeHelpMsg();
 846
 847                 $astriks = str_repeat( '*** ', 14 );
 848                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
 849                 foreach ( array_keys( $this->mModules ) as $moduleName ) {
 850                         $module = new $this->mModules[$moduleName] ( $this, $moduleName );
 851                         $msg .= self::makeHelpMsgHeader( $module, 'action' );
 852                         $msg2 = $module->makeHelpMsg();
 853                         if ( $msg2 !== false ) {
 854                                 $msg .= $msg2;
 855                         }
 856                         $msg .= "\n";
 857                 }
 858
 859                 $msg .= "\n$astriks Permissions $astriks\n\n";
 860                 foreach ( self::$mRights as $right => $rightMsg ) {
 861                         $groups = User::getGroupsWithPermission( $right );
 862                         $msg .= "* " . $right . " *\n  " . wfMsgReplaceArgs( $rightMsg[ 'msg' ], $rightMsg[ 'params' ] ) .
 863                                                 "\nGranted to:\n  " . str_replace( '*', 'all', implode( ', ', $groups ) ) . "\n\n";
 864
 865                 }
 866
 867                 $msg .= "\n$astriks Formats  $astriks\n\n";
 868                 foreach ( array_keys( $this->mFormats ) as $formatName ) {
 869                         $module = $this->createPrinterByName( $formatName );
 870                         $msg .= self::makeHelpMsgHeader( $module, 'format' );
 871                         $msg2 = $module->makeHelpMsg();
 872                         if ( $msg2 !== false ) {
 873                                 $msg .= $msg2;
 874                         }
 875                         $msg .= "\n";
 876                 }
 877
 878                 $msg .= "\n*** Credits: ***\n   " . implode( "\n   ", $this->getCredits() ) . "\n";
 879
 880                 return $msg;
 881         }
 882
 883         /**
 884          * @param  $module ApiBase
 885          * @param  $paramName String What type of request is this? e.g. action, query, list, prop, meta, format
 886          * @return string
 887          */
 888         public static function makeHelpMsgHeader( $module, $paramName ) {
 889                 $modulePrefix = $module->getModulePrefix();
 890                 if ( strval( $modulePrefix ) !== '' ) {
 891                         $modulePrefix = "($modulePrefix) ";
 892                 }
 893
 894                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
 895         }
 896
 897         private $mIsBot = null;
 898         private $mIsSysop = null;
 899         private $mCanApiHighLimits = null;
 900
 901         /**
 902          * Returns true if the currently logged in user is a bot, false otherwise
 903          * OBSOLETE, use canApiHighLimits() instead
 904          */
 905         public function isBot() {
 906                 if ( !isset( $this->mIsBot ) ) {
 907                         global $wgUser;
 908                         $this->mIsBot = $wgUser->isAllowed( 'bot' );
 909                 }
 910                 return $this->mIsBot;
 911         }
 912
 913         /**
 914          * Similar to isBot(), this method returns true if the logged in user is
 915          * a sysop, and false if not.
 916          * OBSOLETE, use canApiHighLimits() instead
 917          */
 918         public function isSysop() {
 919                 if ( !isset( $this->mIsSysop ) ) {
 920                         global $wgUser;
 921                         $this->mIsSysop = in_array( 'sysop', $wgUser->getGroups() );
 922                 }
 923
 924                 return $this->mIsSysop;
 925         }
 926
 927         /**
 928          * Check whether the current user is allowed to use high limits
 929          * @return bool
 930          */
 931         public function canApiHighLimits() {
 932                 if ( !isset( $this->mCanApiHighLimits ) ) {
 933                         global $wgUser;
 934                         $this->mCanApiHighLimits = $wgUser->isAllowed( 'apihighlimits' );
 935                 }
 936
 937                 return $this->mCanApiHighLimits;
 938         }
 939
 940         /**
 941          * Check whether the user wants us to show version information in the API help
 942          * @return bool
 943          */
 944         public function getShowVersions() {
 945                 return $this->mShowVersions;
 946         }
 947
 948         /**
 949          * Returns the version information of this file, plus it includes
 950          * the versions for all files that are not callable proper API modules
 951          */
 952         public function getVersion() {
 953                 $vers = array ();
 954                 $vers[] = 'MediaWiki: ' . SpecialVersion::getVersion() . "\n    http://svn.wikimedia.org/viewvc/mediawiki/trunk/phase3/";
 955                 $vers[] = __CLASS__ . ': $Id$';
 956                 $vers[] = ApiBase::getBaseVersion();
 957                 $vers[] = ApiFormatBase::getBaseVersion();
 958                 $vers[] = ApiQueryBase::getBaseVersion();
 959                 return $vers;
 960         }
 961
 962         /**
 963          * Add or overwrite a module in this ApiMain instance. Intended for use by extending
 964          * classes who wish to add their own modules to their lexicon or override the
 965          * behavior of inherent ones.
 966          *
 967          * @param $mdlName String The identifier for this module.
 968          * @param $mdlClass String The class where this module is implemented.
 969          */
 970         protected function addModule( $mdlName, $mdlClass ) {
 971                 $this->mModules[$mdlName] = $mdlClass;
 972         }
 973
 974         /**
 975          * Add or overwrite an output format for this ApiMain. Intended for use by extending
 976          * classes who wish to add to or modify current formatters.
 977          *
 978          * @param $fmtName The identifier for this format.
 979          * @param $fmtClass The class implementing this format.
 980          */
 981         protected function addFormat( $fmtName, $fmtClass ) {
 982                 $this->mFormats[$fmtName] = $fmtClass;
 983         }
 984
 985         /**
 986          * Get the array mapping module names to class names
 987          * @return array
 988          */
 989         function getModules() {
 990                 return $this->mModules;
 991         }
 992
 993         /**
 994          * Returns the list of supported formats in form ( 'format' => 'ClassName' )
 995          *
 996          * @since 1.18
 997          * @return array
 998          */
 999         public function getFormats() {
1000                 return $this->mFormats;
1001         }
1002 }
1003
1004 /**
1005  * This exception will be thrown when dieUsage is called to stop module execution.
1006  * The exception handling code will print a help screen explaining how this API may be used.
1007  *
1008  * @ingroup API
1009  */
1010 class UsageException extends Exception {
1011
1012         private $mCodestr;
1013         private $mExtraData;
1014
1015         public function __construct( $message, $codestr, $code = 0, $extradata = null ) {
1016                 parent::__construct( $message, $code );
1017                 $this->mCodestr = $codestr;
1018                 $this->mExtraData = $extradata;
1019         }
1020
1021         public function getCodeString() {
1022                 return $this->mCodestr;
1023         }
1024
1025         public function getMessageArray() {
1026                 $result = array(
1027                         'code' => $this->mCodestr,
1028                         'info' => $this->getMessage()
1029                 );
1030                 if ( is_array( $this->mExtraData ) ) {
1031                         $result = array_merge( $result, $this->mExtraData );
1032                 }
1033                 return $result;
1034         }
1035
1036         public function __toString() {
1037                 return "{$this->getCodeString()}: {$this->getMessage()}";
1038         }
1039 }