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                 'feedcontributions' => 'ApiFeedContributions',
  64                 'feedwatchlist' => 'ApiFeedWatchlist',
  65                 'help' => 'ApiHelp',
  66                 'paraminfo' => 'ApiParamInfo',
  67                 'rsd' => 'ApiRsd',
  68                 'compare' => 'ApiComparePages',
  69
  70                 // Write modules
  71                 'purge' => 'ApiPurge',
  72                 'rollback' => 'ApiRollback',
  73                 'delete' => 'ApiDelete',
  74                 'undelete' => 'ApiUndelete',
  75                 'protect' => 'ApiProtect',
  76                 'block' => 'ApiBlock',
  77                 'unblock' => 'ApiUnblock',
  78                 'move' => 'ApiMove',
  79                 'edit' => 'ApiEditPage',
  80                 'upload' => 'ApiUpload',
  81                 'filerevert' => 'ApiFileRevert',
  82                 'emailuser' => 'ApiEmailUser',
  83                 'watch' => 'ApiWatch',
  84                 'patrol' => 'ApiPatrol',
  85                 'import' => 'ApiImport',
  86                 'userrights' => 'ApiUserrights',
  87         );
  88
  89         /**
  90          * List of available formats: format name => format class
  91          */
  92         private static $Formats = array(
  93                 'json' => 'ApiFormatJson',
  94                 'jsonfm' => 'ApiFormatJson',
  95                 'php' => 'ApiFormatPhp',
  96                 'phpfm' => 'ApiFormatPhp',
  97                 'wddx' => 'ApiFormatWddx',
  98                 'wddxfm' => 'ApiFormatWddx',
  99                 'xml' => 'ApiFormatXml',
 100                 'xmlfm' => 'ApiFormatXml',
 101                 'yaml' => 'ApiFormatYaml',
 102                 'yamlfm' => 'ApiFormatYaml',
 103                 'rawfm' => 'ApiFormatJson',
 104                 'txt' => 'ApiFormatTxt',
 105                 'txtfm' => 'ApiFormatTxt',
 106                 'dbg' => 'ApiFormatDbg',
 107                 'dbgfm' => 'ApiFormatDbg',
 108                 'dump' => 'ApiFormatDump',
 109                 'dumpfm' => 'ApiFormatDump',
 110         );
 111
 112         /**
 113          * List of user roles that are specifically relevant to the API.
 114          * array( 'right' => array ( 'msg'    => 'Some message with a $1',
 115          *                           'params' => array ( $someVarToSubst ) ),
 116          *                          );
 117          */
 118         private static $mRights = array(
 119                 'writeapi' => array(
 120                         'msg' => 'Use of the write API',
 121                         'params' => array()
 122                 ),
 123                 'apihighlimits' => array(
 124                         '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.',
 125                         'params' => array( ApiBase::LIMIT_SML2, ApiBase::LIMIT_BIG2 )
 126                 )
 127         );
 128
 129         /**
 130          * @var ApiFormatBase
 131          */
 132         private $mPrinter;
 133
 134         private $mModules, $mModuleNames, $mFormats, $mFormatNames;
 135         private $mResult, $mAction, $mShowVersions, $mEnableWrite, $mRequest;
 136         private $mInternalMode, $mSquidMaxage, $mModule;
 137
 138         private $mCacheMode = 'private';
 139         private $mCacheControl = array();
 140
 141         /**
 142          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 143          *
 144          * @param $request WebRequest - if this is an instance of FauxRequest, errors are thrown and no printing occurs
 145          * @param $enableWrite bool should be set to true if the api may modify data
 146          */
 147         public function __construct( $request, $enableWrite = false ) {
 148                 $this->mInternalMode = ( $request instanceof FauxRequest );
 149
 150                 // Special handling for the main module: $parent === $this
 151                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 152
 153                 if ( !$this->mInternalMode ) {
 154                         // Impose module restrictions.
 155                         // If the current user cannot read,
 156                         // Remove all modules other than login
 157                         global $wgUser;
 158
 159                         if ( $request->getVal( 'callback' ) !== null ) {
 160                                 // JSON callback allows cross-site reads.
 161                                 // For safety, strip user credentials.
 162                                 wfDebug( "API: stripping user credentials for JSON callback\n" );
 163                                 $wgUser = new User();
 164                         }
 165                 }
 166
 167                 global $wgAPIModules; // extension modules
 168                 $this->mModules = $wgAPIModules + self::$Modules;
 169
 170                 $this->mModuleNames = array_keys( $this->mModules );
 171                 $this->mFormats = self::$Formats;
 172                 $this->mFormatNames = array_keys( $this->mFormats );
 173
 174                 $this->mResult = new ApiResult( $this );
 175                 $this->mShowVersions = false;
 176                 $this->mEnableWrite = $enableWrite;
 177
 178                 $this->mRequest = &$request;
 179
 180                 $this->mSquidMaxage = - 1; // flag for executeActionWithErrorHandling()
 181                 $this->mCommit = false;
 182         }
 183
 184         /**
 185          * Return true if the API was started by other PHP code using FauxRequest
 186          * @return bool
 187          */
 188         public function isInternalMode() {
 189                 return $this->mInternalMode;
 190         }
 191
 192         /**
 193          * Return the request object that contains client's request
 194          * @return WebRequest
 195          */
 196         public function getRequest() {
 197                 return $this->mRequest;
 198         }
 199
 200         /**
 201          * Get the ApiResult object associated with current request
 202          *
 203          * @return ApiResult
 204          */
 205         public function getResult() {
 206                 return $this->mResult;
 207         }
 208
 209         /**
 210          * Get the API module object. Only works after executeAction()
 211          *
 212          * @return ApiBase
 213          */
 214         public function getModule() {
 215                 return $this->mModule;
 216         }
 217
 218         /**
 219          * Get the result formatter object. Only works after setupExecuteAction()
 220          *
 221          * @return ApiFormatBase
 222          */
 223         public function getPrinter() {
 224                 return $this->mPrinter;
 225         }
 226
 227         /**
 228          * Set how long the response should be cached.
 229          *
 230          * @param $maxage
 231          */
 232         public function setCacheMaxAge( $maxage ) {
 233                 $this->setCacheControl( array(
 234                         'max-age' => $maxage,
 235                         's-maxage' => $maxage
 236                 ) );
 237         }
 238
 239         /**
 240          * Set the type of caching headers which will be sent.
 241          *
 242          * @param $mode String One of:
 243          *    - 'public':     Cache this object in public caches, if the maxage or smaxage
 244          *         parameter is set, or if setCacheMaxAge() was called. If a maximum age is
 245          *         not provided by any of these means, the object will be private.
 246          *    - 'private':    Cache this object only in private client-side caches.
 247          *    - 'anon-public-user-private': Make this object cacheable for logged-out
 248          *         users, but private for logged-in users. IMPORTANT: If this is set, it must be
 249          *         set consistently for a given URL, it cannot be set differently depending on
 250          *         things like the contents of the database, or whether the user is logged in.
 251          *
 252          *  If the wiki does not allow anonymous users to read it, the mode set here
 253          *  will be ignored, and private caching headers will always be sent. In other words,
 254          *  the "public" mode is equivalent to saying that the data sent is as public as a page
 255          *  view.
 256          *
 257          *  For user-dependent data, the private mode should generally be used. The
 258          *  anon-public-user-private mode should only be used where there is a particularly
 259          *  good performance reason for caching the anonymous response, but where the
 260          *  response to logged-in users may differ, or may contain private data.
 261          *
 262          *  If this function is never called, then the default will be the private mode.
 263          */
 264         public function setCacheMode( $mode ) {
 265                 if ( !in_array( $mode, array( 'private', 'public', 'anon-public-user-private' ) ) ) {
 266                         wfDebug( __METHOD__ . ": unrecognised cache mode \"$mode\"\n" );
 267                         // Ignore for forwards-compatibility
 268                         return;
 269                 }
 270
 271                 if ( !in_array( 'read', User::getGroupPermissions( array( '*' ) ), true ) ) {
 272                         // Private wiki, only private headers
 273                         if ( $mode !== 'private' ) {
 274                                 wfDebug( __METHOD__ . ": ignoring request for $mode cache mode, private wiki\n" );
 275                                 return;
 276                         }
 277                 }
 278
 279                 wfDebug( __METHOD__ . ": setting cache mode $mode\n" );
 280                 $this->mCacheMode = $mode;
 281         }
 282
 283         /**
 284          * @deprecated since 1.17 Private caching is now the default, so there is usually no
 285          * need to call this function. If there is a need, you can use
 286          * $this->setCacheMode('private')
 287          */
 288         public function setCachePrivate() {
 289                 $this->setCacheMode( 'private' );
 290         }
 291
 292         /**
 293          * Set directives (key/value pairs) for the Cache-Control header.
 294          * Boolean values will be formatted as such, by including or omitting
 295          * without an equals sign.
 296          *
 297          * Cache control values set here will only be used if the cache mode is not
 298          * private, see setCacheMode().
 299          *
 300          * @param $directives array
 301          */
 302         public function setCacheControl( $directives ) {
 303                 $this->mCacheControl = $directives + $this->mCacheControl;
 304         }
 305
 306         /**
 307          * Make sure Vary: Cookie and friends are set. Use this when the output of a request
 308          * may be cached for anons but may not be cached for logged-in users.
 309          *
 310          * WARNING: This function must be called CONSISTENTLY for a given URL. This means that a
 311          * given URL must either always or never call this function; if it sometimes does and
 312          * sometimes doesn't, stuff will break.
 313          *
 314          * @deprecated since 1.17 Use setCacheMode( 'anon-public-user-private' )
 315          */
 316         public function setVaryCookie() {
 317                 $this->setCacheMode( 'anon-public-user-private' );
 318         }
 319
 320         /**
 321          * Create an instance of an output formatter by its name
 322          *
 323          * @param $format string
 324          *
 325          * @return ApiFormatBase
 326          */
 327         public function createPrinterByName( $format ) {
 328                 if ( !isset( $this->mFormats[$format] ) ) {
 329                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 330                 }
 331                 return new $this->mFormats[$format] ( $this, $format );
 332         }
 333
 334         /**
 335          * Execute api request. Any errors will be handled if the API was called by the remote client.
 336          */
 337         public function execute() {
 338                 $this->profileIn();
 339                 if ( $this->mInternalMode ) {
 340                         $this->executeAction();
 341                 } else {
 342                         $this->executeActionWithErrorHandling();
 343                 }
 344
 345                 $this->profileOut();
 346         }
 347
 348         /**
 349          * Execute an action, and in case of an error, erase whatever partial results
 350          * have been accumulated, and replace it with an error message and a help screen.
 351          */
 352         protected function executeActionWithErrorHandling() {
 353                 // In case an error occurs during data output,
 354                 // clear the output buffer and print just the error information
 355                 ob_start();
 356
 357                 try {
 358                         $this->executeAction();
 359                 } catch ( Exception $e ) {
 360                         // Log it
 361                         if ( $e instanceof MWException ) {
 362                                 wfDebugLog( 'exception', $e->getLogMessage() );
 363                         }
 364
 365                         // Handle any kind of exception by outputing properly formatted error message.
 366                         // If this fails, an unhandled exception should be thrown so that global error
 367                         // handler will process and log it.
 368
 369                         $errCode = $this->substituteResultWithError( $e );
 370
 371                         // Error results should not be cached
 372                         $this->setCacheMode( 'private' );
 373
 374                         $response = $this->getRequest()->response();
 375                         $headerStr = 'MediaWiki-API-Error: ' . $errCode;
 376                         if ( $e->getCode() === 0 ) {
 377                                 $response->header( $headerStr );
 378                         } else {
 379                                 $response->header( $headerStr, true, $e->getCode() );
 380                         }
 381
 382                         // Reset and print just the error message
 383                         ob_clean();
 384
 385                         // If the error occured during printing, do a printer->profileOut()
 386                         $this->mPrinter->safeProfileOut();
 387                         $this->printResult( true );
 388                 }
 389
 390                 // Send cache headers after any code which might generate an error, to
 391                 // avoid sending public cache headers for errors.
 392                 $this->sendCacheHeaders();
 393
 394                 if ( $this->mPrinter->getIsHtml() && !$this->mPrinter->isDisabled() ) {
 395                         echo wfReportTime();
 396                 }
 397
 398                 ob_end_flush();
 399         }
 400
 401         protected function sendCacheHeaders() {
 402                 global $wgUseXVO, $wgOut, $wgVaryOnXFPForAPI;
 403                 $response = $this->getRequest()->response();
 404
 405                 if ( $this->mCacheMode == 'private' ) {
 406                         $response->header( 'Cache-Control: private' );
 407                         return;
 408                 }
 409
 410                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 411                         $xfp = $wgVaryOnXFPForAPI ? ', X-Forwarded-Proto' : '';
 412                         $response->header( 'Vary: Accept-Encoding, Cookie' . $xfp );
 413                         if ( $wgUseXVO ) {
 414                                 if ( $wgVaryOnXFPForAPI ) {
 415                                         $wgOut->addVaryHeader( 'X-Forwarded-Proto' );
 416                                 }
 417                                 $response->header( $wgOut->getXVO() );
 418                                 if ( $wgOut->haveCacheVaryCookies() ) {
 419                                         // Logged in, mark this request private
 420                                         $response->header( 'Cache-Control: private' );
 421                                         return;
 422                                 }
 423                                 // Logged out, send normal public headers below
 424                         } elseif ( session_id() != '' ) {
 425                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 426                                 // Mark request private
 427                                 $response->header( 'Cache-Control: private' );
 428                                 return;
 429                         } // else no XVO and anonymous, send public headers below
 430                 }
 431
 432                 // Send public headers
 433                 if ( $wgVaryOnXFPForAPI ) {
 434                         $response->header( 'Vary: Accept-Encoding, X-Forwarded-Proto' );
 435                         if ( $wgUseXVO ) {
 436                                 // Bleeeeegh. Our header setting system sucks
 437                                 $response->header( 'X-Vary-Options: Accept-Encoding;list-contains=gzip, X-Forwarded-Proto' );
 438                         }
 439                 }
 440
 441                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 442                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 443                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 444                 }
 445                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 446                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 447                 }
 448
 449                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 450                         // Public cache not requested
 451                         // Sending a Vary header in this case is harmless, and protects us
 452                         // against conditional calls of setCacheMaxAge().
 453                         $response->header( 'Cache-Control: private' );
 454                         return;
 455                 }
 456
 457                 $this->mCacheControl['public'] = true;
 458
 459                 // Send an Expires header
 460                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 461                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 462                 $response->header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 463
 464                 // Construct the Cache-Control header
 465                 $ccHeader = '';
 466                 $separator = '';
 467                 foreach ( $this->mCacheControl as $name => $value ) {
 468                         if ( is_bool( $value ) ) {
 469                                 if ( $value ) {
 470                                         $ccHeader .= $separator . $name;
 471                                         $separator = ', ';
 472                                 }
 473                         } else {
 474                                 $ccHeader .= $separator . "$name=$value";
 475                                 $separator = ', ';
 476                         }
 477                 }
 478
 479                 $response->header( "Cache-Control: $ccHeader" );
 480         }
 481
 482         /**
 483          * Replace the result data with the information about an exception.
 484          * Returns the error code
 485          * @param $e Exception
 486          * @return string
 487          */
 488         protected function substituteResultWithError( $e ) {
 489                 $result = $this->getResult();
 490                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 491                 if ( !isset ( $this->mPrinter ) ) {
 492                         // The printer has not been created yet. Try to manually get formatter value.
 493                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 494                         if ( !in_array( $value, $this->mFormatNames ) ) {
 495                                 $value = self::API_DEFAULT_FORMAT;
 496                         }
 497
 498                         $this->mPrinter = $this->createPrinterByName( $value );
 499                         if ( $this->mPrinter->getNeedsRawData() ) {
 500                                 $result->setRawMode();
 501                         }
 502                 }
 503
 504                 if ( $e instanceof UsageException ) {
 505                         // User entered incorrect parameters - print usage screen
 506                         $errMessage = $e->getMessageArray();
 507
 508                         // Only print the help message when this is for the developer, not runtime
 509                         if ( $this->mPrinter->getWantsHelp() || $this->mAction == 'help' ) {
 510                                 ApiResult::setContent( $errMessage, $this->makeHelpMsg() );
 511                         }
 512
 513                 } else {
 514                         global $wgShowSQLErrors, $wgShowExceptionDetails;
 515                         // Something is seriously wrong
 516                         if ( ( $e instanceof DBQueryError ) && !$wgShowSQLErrors ) {
 517                                 $info = 'Database query error';
 518                         } else {
 519                                 $info = "Exception Caught: {$e->getMessage()}";
 520                         }
 521
 522                         $errMessage = array(
 523                                 'code' => 'internal_api_error_' . get_class( $e ),
 524                                 'info' => $info,
 525                         );
 526                         ApiResult::setContent( $errMessage, $wgShowExceptionDetails ? "\n\n{$e->getTraceAsString()}\n\n" : '' );
 527                 }
 528
 529                 $result->reset();
 530                 $result->disableSizeCheck();
 531                 // Re-add the id
 532                 $requestid = $this->getParameter( 'requestid' );
 533                 if ( !is_null( $requestid ) ) {
 534                         $result->addValue( null, 'requestid', $requestid );
 535                 }
 536                 // servedby is especially useful when debugging errors
 537                 $result->addValue( null, 'servedby', wfHostName() );
 538                 $result->addValue( null, 'error', $errMessage );
 539
 540                 return $errMessage['code'];
 541         }
 542
 543         /**
 544          * Set up for the execution.
 545          * @return array
 546          */
 547         protected function setupExecuteAction() {
 548                 // First add the id to the top element
 549                 $result = $this->getResult();
 550                 $requestid = $this->getParameter( 'requestid' );
 551                 if ( !is_null( $requestid ) ) {
 552                         $result->addValue( null, 'requestid', $requestid );
 553                 }
 554                 $servedby = $this->getParameter( 'servedby' );
 555                 if ( $servedby ) {
 556                         $result->addValue( null, 'servedby', wfHostName() );
 557                 }
 558
 559                 $params = $this->extractRequestParams();
 560
 561                 $this->mShowVersions = $params['version'];
 562                 $this->mAction = $params['action'];
 563
 564                 if ( !is_string( $this->mAction ) ) {
 565                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 566                 }
 567
 568                 return $params;
 569         }
 570
 571         /**
 572          * Set up the module for response
 573          * @return ApiBase The module that will handle this action
 574          */
 575         protected function setupModule() {
 576                 // Instantiate the module requested by the user
 577                 $module = new $this->mModules[$this->mAction] ( $this, $this->mAction );
 578                 $this->mModule = $module;
 579
 580                 $moduleParams = $module->extractRequestParams();
 581
 582                 // Die if token required, but not provided (unless there is a gettoken parameter)
 583                 $salt = $module->getTokenSalt();
 584                 if ( $salt !== false && !isset( $moduleParams['gettoken'] ) ) {
 585                         if ( !isset( $moduleParams['token'] ) ) {
 586                                 $this->dieUsageMsg( array( 'missingparam', 'token' ) );
 587                         } else {
 588                                 global $wgUser;
 589                                 if ( !$wgUser->matchEditToken( $moduleParams['token'], $salt, $this->getRequest() ) ) {
 590                                         $this->dieUsageMsg( 'sessionfailure' );
 591                                 }
 592                         }
 593                 }
 594                 return $module;
 595         }
 596
 597         /**
 598          * Check the max lag if necessary
 599          * @param $module ApiBase object: Api module being used
 600          * @param $params Array an array containing the request parameters.
 601          * @return boolean True on success, false should exit immediately
 602          */
 603         protected function checkMaxLag( $module, $params ) {
 604                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
 605                         // Check for maxlag
 606                         global $wgShowHostnames;
 607                         $maxLag = $params['maxlag'];
 608                         list( $host, $lag ) = wfGetLB()->getMaxLag();
 609                         if ( $lag > $maxLag ) {
 610                                 $response = $this->getRequest()->response();
 611
 612                                 $response->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
 613                                 $response->header( 'X-Database-Lag: ' . intval( $lag ) );
 614
 615                                 if ( $wgShowHostnames ) {
 616                                         $this->dieUsage( "Waiting for $host: $lag seconds lagged", 'maxlag' );
 617                                 } else {
 618                                         $this->dieUsage( "Waiting for a database server: $lag seconds lagged", 'maxlag' );
 619                                 }
 620                                 return false;
 621                         }
 622                 }
 623                 return true;
 624         }
 625
 626         /**
 627          * Check for sufficient permissions to execute
 628          * @param $module ApiBase An Api module
 629          */
 630         protected function checkExecutePermissions( $module ) {
 631                 global $wgUser;
 632                 if ( $module->isReadMode() && !in_array( 'read', User::getGroupPermissions( array( '*' ) ), true ) &&
 633                         !$wgUser->isAllowed( 'read' ) )
 634                 {
 635                         $this->dieUsageMsg( 'readrequired' );
 636                 }
 637                 if ( $module->isWriteMode() ) {
 638                         if ( !$this->mEnableWrite ) {
 639                                 $this->dieUsageMsg( 'writedisabled' );
 640                         }
 641                         if ( !$wgUser->isAllowed( 'writeapi' ) ) {
 642                                 $this->dieUsageMsg( 'writerequired' );
 643                         }
 644                         if ( wfReadOnly() ) {
 645                                 $this->dieReadOnly();
 646                         }
 647                 }
 648         }
 649
 650         /**
 651          * Check POST for external response and setup result printer
 652          * @param $module ApiBase An Api module
 653          * @param $params Array an array with the request parameters
 654          */
 655         protected function setupExternalResponse( $module, $params ) {
 656                 // Ignore mustBePosted() for internal calls
 657                 if ( $module->mustBePosted() && !$this->mRequest->wasPosted() ) {
 658                         $this->dieUsageMsg( array( 'mustbeposted', $this->mAction ) );
 659                 }
 660
 661                 // See if custom printer is used
 662                 $this->mPrinter = $module->getCustomPrinter();
 663                 if ( is_null( $this->mPrinter ) ) {
 664                         // Create an appropriate printer
 665                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
 666                 }
 667
 668                 if ( $this->mPrinter->getNeedsRawData() ) {
 669                         $this->getResult()->setRawMode();
 670                 }
 671         }
 672
 673         /**
 674          * Execute the actual module, without any error handling
 675          */
 676         protected function executeAction() {
 677                 $params = $this->setupExecuteAction();
 678                 $module = $this->setupModule();
 679
 680                 $this->checkExecutePermissions( $module );
 681
 682                 if ( !$this->checkMaxLag( $module, $params ) ) {
 683                         return;
 684                 }
 685
 686                 if ( !$this->mInternalMode ) {
 687                         $this->setupExternalResponse( $module, $params );
 688                 }
 689
 690                 // Execute
 691                 $module->profileIn();
 692                 $module->execute();
 693                 wfRunHooks( 'APIAfterExecute', array( &$module ) );
 694                 $module->profileOut();
 695
 696                 if ( !$this->mInternalMode ) {
 697                         // Print result data
 698                         $this->printResult( false );
 699                 }
 700         }
 701
 702         /**
 703          * Print results using the current printer
 704          *
 705          * @param $isError bool
 706          */
 707         protected function printResult( $isError ) {
 708                 $this->getResult()->cleanUpUTF8();
 709                 $printer = $this->mPrinter;
 710                 $printer->profileIn();
 711
 712                 /**
 713                  * If the help message is requested in the default (xmlfm) format,
 714                  * tell the printer not to escape ampersands so that our links do
 715                  * not break.
 716                  */
 717                 $printer->setUnescapeAmps( ( $this->mAction == 'help' || $isError )
 718                                 && $printer->getFormat() == 'XML' && $printer->getIsHtml() );
 719
 720                 $printer->initPrinter( $isError );
 721
 722                 $printer->execute();
 723                 $printer->closePrinter();
 724                 $printer->profileOut();
 725         }
 726
 727         /**
 728          * @return bool
 729          */
 730         public function isReadMode() {
 731                 return false;
 732         }
 733
 734         /**
 735          * See ApiBase for description.
 736          *
 737          * @return array
 738          */
 739         public function getAllowedParams() {
 740                 return array(
 741                         'format' => array(
 742                                 ApiBase::PARAM_DFLT => ApiMain::API_DEFAULT_FORMAT,
 743                                 ApiBase::PARAM_TYPE => $this->mFormatNames
 744                         ),
 745                         'action' => array(
 746                                 ApiBase::PARAM_DFLT => 'help',
 747                                 ApiBase::PARAM_TYPE => $this->mModuleNames
 748                         ),
 749                         'version' => false,
 750                         'maxlag'  => array(
 751                                 ApiBase::PARAM_TYPE => 'integer'
 752                         ),
 753                         'smaxage' => array(
 754                                 ApiBase::PARAM_TYPE => 'integer',
 755                                 ApiBase::PARAM_DFLT => 0
 756                         ),
 757                         'maxage' => array(
 758                                 ApiBase::PARAM_TYPE => 'integer',
 759                                 ApiBase::PARAM_DFLT => 0
 760                         ),
 761                         'requestid' => null,
 762                         'servedby'  => false,
 763                 );
 764         }
 765
 766         /**
 767          * See ApiBase for description.
 768          *
 769          * @return array
 770          */
 771         public function getParamDescription() {
 772                 return array(
 773                         'format' => 'The format of the output',
 774                         'action' => 'What action you would like to perform. See below for module help',
 775                         'version' => 'When showing help, include version for each module',
 776                         'maxlag' => array(
 777                                 'Maximum lag can be used when MediaWiki is installed on a database replicated cluster.',
 778                                 'To save actions causing any more site replication lag, this parameter can make the client',
 779                                 'wait until the replication lag is less than the specified value.',
 780                                 'In case of a replag error, a HTTP 503 error is returned, with the message like',
 781                                 '"Waiting for $host: $lag seconds lagged\n".',
 782                                 'See http://www.mediawiki.org/wiki/Manual:Maxlag_parameter for more information',
 783                         ),
 784                         'smaxage' => 'Set the s-maxage header to this many seconds. Errors are never cached',
 785                         'maxage' => 'Set the max-age header to this many seconds. Errors are never cached',
 786                         'requestid' => 'Request ID to distinguish requests. This will just be output back to you',
 787                         'servedby' => 'Include the hostname that served the request in the results. Unconditionally shown on error',
 788                 );
 789         }
 790
 791         /**
 792          * See ApiBase for description.
 793          *
 794          * @return array
 795          */
 796         public function getDescription() {
 797                 return array(
 798                         '',
 799                         '',
 800                         '**********************************************************************************************************',
 801                         '**                                                                                                      **',
 802                         '**                      This is an auto-generated MediaWiki API documentation page                      **',
 803                         '**                                                                                                      **',
 804                         '**                                    Documentation and Examples:                                       **',
 805                         '**                                 http://www.mediawiki.org/wiki/API                                    **',
 806                         '**                                                                                                      **',
 807                         '**********************************************************************************************************',
 808                         '',
 809                         'Status:                All features shown on this page should be working, but the API',
 810                         '                       is still in active development, and may change at any time.',
 811                         '                       Make sure to monitor our mailing list for any updates',
 812                         '',
 813                         'Erroneous requests:    When erroneous requests are sent to the API, a HTTP header will be sent',
 814                         '                       with the key "MediaWiki-API-Error" and then both the value of the',
 815                         '                       header and the error code sent back will be set to the same value',
 816                         '',
 817                         '                       In the case of an invalid action being passed, these will have a value',
 818                         '                       of "unknown_action"',
 819                         '',
 820                         '                       For more information see http://www.mediawiki.org/wiki/API:Errors_and_warnings',
 821                         '',
 822                         'Documentation:         http://www.mediawiki.org/wiki/API:Main_page',
 823                         'FAQ                    http://www.mediawiki.org/wiki/API:FAQ',
 824                         'Mailing list:          http://lists.wikimedia.org/mailman/listinfo/mediawiki-api',
 825                         'Api Announcements:     http://lists.wikimedia.org/mailman/listinfo/mediawiki-api-announce',
 826                         'Bugs & Requests:       http://bugzilla.wikimedia.org/buglist.cgi?component=API&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&order=bugs.delta_ts',
 827                         '',
 828                         '',
 829                         '',
 830                         '',
 831                         '',
 832                 );
 833         }
 834
 835         /**
 836          * @return array
 837          */
 838         public function getPossibleErrors() {
 839                 return array_merge( parent::getPossibleErrors(), array(
 840                         array( 'readonlytext' ),
 841                         array( 'code' => 'unknown_format', 'info' => 'Unrecognized format: format' ),
 842                         array( 'code' => 'unknown_action', 'info' => 'The API requires a valid action parameter' ),
 843                         array( 'code' => 'maxlag', 'info' => 'Waiting for host: x seconds lagged' ),
 844                         array( 'code' => 'maxlag', 'info' => 'Waiting for a database server: x seconds lagged' ),
 845                 ) );
 846         }
 847
 848         /**
 849          * Returns an array of strings with credits for the API
 850          * @return array
 851          */
 852         protected function getCredits() {
 853                 return array(
 854                         'API developers:',
 855                         '    Roan Kattouw <Firstname>.<Lastname>@gmail.com (lead developer Sep 2007-present)',
 856                         '    Victor Vasiliev - vasilvv at gee mail dot com',
 857                         '    Bryan Tong Minh - bryan . tongminh @ gmail . com',
 858                         '    Sam Reed - sam @ reedyboy . net',
 859                         '    Yuri Astrakhan <Firstname><Lastname>@gmail.com (creator, lead developer Sep 2006-Sep 2007)',
 860                         '',
 861                         'Please send your comments, suggestions and questions to mediawiki-api@lists.wikimedia.org',
 862                         'or file a bug report at http://bugzilla.wikimedia.org/'
 863                 );
 864         }
 865
 866         /**
 867          * Sets whether the pretty-printer should format *bold* and $italics$
 868          *
 869          * @param $help bool
 870          */
 871         public function setHelp( $help = true ) {
 872                 $this->mPrinter->setHelp( $help );
 873         }
 874
 875         /**
 876          * Override the parent to generate help messages for all available modules.
 877          *
 878          * @return string
 879          */
 880         public function makeHelpMsg() {
 881                 global $wgMemc, $wgAPICacheHelpTimeout;
 882                 $this->setHelp();
 883                 // Get help text from cache if present
 884                 $key = wfMemcKey( 'apihelp', $this->getModuleName(),
 885                         SpecialVersion::getVersion( 'nodb' ) .
 886                         $this->getShowVersions() );
 887                 if ( $wgAPICacheHelpTimeout > 0 ) {
 888                         $cached = $wgMemc->get( $key );
 889                         if ( $cached ) {
 890                                 return $cached;
 891                         }
 892                 }
 893                 $retval = $this->reallyMakeHelpMsg();
 894                 if ( $wgAPICacheHelpTimeout > 0 ) {
 895                         $wgMemc->set( $key, $retval, $wgAPICacheHelpTimeout );
 896                 }
 897                 return $retval;
 898         }
 899
 900         /**
 901          * @return mixed|string
 902          */
 903         public function reallyMakeHelpMsg() {
 904                 $this->setHelp();
 905
 906                 // Use parent to make default message for the main module
 907                 $msg = parent::makeHelpMsg();
 908
 909                 $astriks = str_repeat( '*** ', 14 );
 910                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
 911                 foreach ( array_keys( $this->mModules ) as $moduleName ) {
 912                         $module = new $this->mModules[$moduleName] ( $this, $moduleName );
 913                         $msg .= self::makeHelpMsgHeader( $module, 'action' );
 914                         $msg2 = $module->makeHelpMsg();
 915                         if ( $msg2 !== false ) {
 916                                 $msg .= $msg2;
 917                         }
 918                         $msg .= "\n";
 919                 }
 920
 921                 $msg .= "\n$astriks Permissions $astriks\n\n";
 922                 foreach ( self::$mRights as $right => $rightMsg ) {
 923                         $groups = User::getGroupsWithPermission( $right );
 924                         $msg .= "* " . $right . " *\n  " . wfMsgReplaceArgs( $rightMsg[ 'msg' ], $rightMsg[ 'params' ] ) .
 925                                                 "\nGranted to:\n  " . str_replace( '*', 'all', implode( ', ', $groups ) ) . "\n\n";
 926
 927                 }
 928
 929                 $msg .= "\n$astriks Formats  $astriks\n\n";
 930                 foreach ( array_keys( $this->mFormats ) as $formatName ) {
 931                         $module = $this->createPrinterByName( $formatName );
 932                         $msg .= self::makeHelpMsgHeader( $module, 'format' );
 933                         $msg2 = $module->makeHelpMsg();
 934                         if ( $msg2 !== false ) {
 935                                 $msg .= $msg2;
 936                         }
 937                         $msg .= "\n";
 938                 }
 939
 940                 $msg .= "\n*** Credits: ***\n   " . implode( "\n   ", $this->getCredits() ) . "\n";
 941
 942                 return $msg;
 943         }
 944
 945         /**
 946          * @param $module ApiBase
 947          * @param $paramName String What type of request is this? e.g. action, query, list, prop, meta, format
 948          * @return string
 949          */
 950         public static function makeHelpMsgHeader( $module, $paramName ) {
 951                 $modulePrefix = $module->getModulePrefix();
 952                 if ( strval( $modulePrefix ) !== '' ) {
 953                         $modulePrefix = "($modulePrefix) ";
 954                 }
 955
 956                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
 957         }
 958
 959         private $mCanApiHighLimits = null;
 960
 961         /**
 962          * Check whether the current user is allowed to use high limits
 963          * @return bool
 964          */
 965         public function canApiHighLimits() {
 966                 if ( !isset( $this->mCanApiHighLimits ) ) {
 967                         global $wgUser;
 968                         $this->mCanApiHighLimits = $wgUser->isAllowed( 'apihighlimits' );
 969                 }
 970
 971                 return $this->mCanApiHighLimits;
 972         }
 973
 974         /**
 975          * Check whether the user wants us to show version information in the API help
 976          * @return bool
 977          */
 978         public function getShowVersions() {
 979                 return $this->mShowVersions;
 980         }
 981
 982         /**
 983          * Returns the version information of this file, plus it includes
 984          * the versions for all files that are not callable proper API modules
 985          *
 986          * @return array
 987          */
 988         public function getVersion() {
 989                 $vers = array();
 990                 $vers[] = 'MediaWiki: ' . SpecialVersion::getVersion() . "\n    http://svn.wikimedia.org/viewvc/mediawiki/trunk/phase3/";
 991                 $vers[] = __CLASS__ . ': $Id$';
 992                 $vers[] = ApiBase::getBaseVersion();
 993                 $vers[] = ApiFormatBase::getBaseVersion();
 994                 $vers[] = ApiQueryBase::getBaseVersion();
 995                 return $vers;
 996         }
 997
 998         /**
 999          * Add or overwrite a module in this ApiMain instance. Intended for use by extending
1000          * classes who wish to add their own modules to their lexicon or override the
1001          * behavior of inherent ones.
1002          *
1003          * @param $mdlName String The identifier for this module.
1004          * @param $mdlClass String The class where this module is implemented.
1005          */
1006         protected function addModule( $mdlName, $mdlClass ) {
1007                 $this->mModules[$mdlName] = $mdlClass;
1008         }
1009
1010         /**
1011          * Add or overwrite an output format for this ApiMain. Intended for use by extending
1012          * classes who wish to add to or modify current formatters.
1013          *
1014          * @param $fmtName string The identifier for this format.
1015          * @param $fmtClass ApiFormatBase The class implementing this format.
1016          */
1017         protected function addFormat( $fmtName, $fmtClass ) {
1018                 $this->mFormats[$fmtName] = $fmtClass;
1019         }
1020
1021         /**
1022          * Get the array mapping module names to class names
1023          * @return array
1024          */
1025         function getModules() {
1026                 return $this->mModules;
1027         }
1028
1029         /**
1030          * Returns the list of supported formats in form ( 'format' => 'ClassName' )
1031          *
1032          * @since 1.18
1033          * @return array
1034          */
1035         public function getFormats() {
1036                 return $this->mFormats;
1037         }
1038 }
1039
1040 /**
1041  * This exception will be thrown when dieUsage is called to stop module execution.
1042  * The exception handling code will print a help screen explaining how this API may be used.
1043  *
1044  * @ingroup API
1045  */
1046 class UsageException extends Exception {
1047
1048         private $mCodestr;
1049         private $mExtraData;
1050
1051         public function __construct( $message, $codestr, $code = 0, $extradata = null ) {
1052                 parent::__construct( $message, $code );
1053                 $this->mCodestr = $codestr;
1054                 $this->mExtraData = $extradata;
1055         }
1056
1057         /**
1058          * @return string
1059          */
1060         public function getCodeString() {
1061                 return $this->mCodestr;
1062         }
1063
1064         /**
1065          * @return array
1066          */
1067         public function getMessageArray() {
1068                 $result = array(
1069                         'code' => $this->mCodestr,
1070                         'info' => $this->getMessage()
1071                 );
1072                 if ( is_array( $this->mExtraData ) ) {
1073                         $result = array_merge( $result, $this->mExtraData );
1074                 }
1075                 return $result;
1076         }
1077
1078         /**
1079          * @return string
1080          */
1081         public function __toString() {
1082                 return "{$this->getCodeString()}: {$this->getMessage()}";
1083         }
1084 }