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