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          * @param $directives array
 300          */
 301         public function setCacheControl( $directives ) {
 302                 $this->mCacheControl = $directives + $this->mCacheControl;
 303         }
 304
 305         /**
 306          * Make sure Vary: Cookie and friends are set. Use this when the output of a request
 307          * may be cached for anons but may not be cached for logged-in users.
 308          *
 309          * WARNING: This function must be called CONSISTENTLY for a given URL. This means that a
 310          * given URL must either always or never call this function; if it sometimes does and
 311          * sometimes doesn't, stuff will break.
 312          *
 313          * @deprecated since 1.17 Use setCacheMode( 'anon-public-user-private' )
 314          */
 315         public function setVaryCookie() {
 316                 $this->setCacheMode( 'anon-public-user-private' );
 317         }
 318
 319         /**
 320          * Create an instance of an output formatter by its name
 321          *
 322          * @param $format string
 323          *
 324          * @return ApiFormatBase
 325          */
 326         public function createPrinterByName( $format ) {
 327                 if ( !isset( $this->mFormats[$format] ) ) {
 328                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 329                 }
 330                 return new $this->mFormats[$format] ( $this, $format );
 331         }
 332
 333         /**
 334          * Execute api request. Any errors will be handled if the API was called by the remote client.
 335          */
 336         public function execute() {
 337                 $this->profileIn();
 338                 if ( $this->mInternalMode ) {
 339                         $this->executeAction();
 340                 } else {
 341                         $this->executeActionWithErrorHandling();
 342                 }
 343
 344                 $this->profileOut();
 345         }
 346
 347         /**
 348          * Execute an action, and in case of an error, erase whatever partial results
 349          * have been accumulated, and replace it with an error message and a help screen.
 350          */
 351         protected function executeActionWithErrorHandling() {
 352                 // In case an error occurs during data output,
 353                 // clear the output buffer and print just the error information
 354                 ob_start();
 355
 356                 try {
 357                         $this->executeAction();
 358                 } catch ( Exception $e ) {
 359                         // Log it
 360                         if ( $e instanceof MWException ) {
 361                                 wfDebugLog( 'exception', $e->getLogMessage() );
 362                         }
 363
 364                         // Handle any kind of exception by outputing properly formatted error message.
 365                         // If this fails, an unhandled exception should be thrown so that global error
 366                         // handler will process and log it.
 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( '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          * Check for sufficient permissions to execute
 606          * @param $module ApiBase An Api module
 607          */
 608         protected function checkExecutePermissions( $module ) {
 609                 global $wgUser;
 610                 if ( $module->isReadMode() && !in_array( 'read', User::getGroupPermissions( array( '*' ) ), true ) &&
 611                         !$wgUser->isAllowed( 'read' ) )
 612                 {
 613                         $this->dieUsageMsg( 'readrequired' );
 614                 }
 615                 if ( $module->isWriteMode() ) {
 616                         if ( !$this->mEnableWrite ) {
 617                                 $this->dieUsageMsg( 'writedisabled' );
 618                         }
 619                         if ( !$wgUser->isAllowed( 'writeapi' ) ) {
 620                                 $this->dieUsageMsg( 'writerequired' );
 621                         }
 622                         if ( wfReadOnly() ) {
 623                                 $this->dieReadOnly();
 624                         }
 625                 }
 626         }
 627
 628         /**
 629          * Check POST for external response and setup result printer
 630          * @param $module ApiBase An Api module
 631          * @param $params Array an array with the request parameters
 632          */
 633         protected function setupExternalResponse( $module, $params ) {
 634                 // Ignore mustBePosted() for internal calls
 635                 if ( $module->mustBePosted() && !$this->mRequest->wasPosted() ) {
 636                         $this->dieUsageMsg( array( 'mustbeposted', $this->mAction ) );
 637                 }
 638
 639                 // See if custom printer is used
 640                 $this->mPrinter = $module->getCustomPrinter();
 641                 if ( is_null( $this->mPrinter ) ) {
 642                         // Create an appropriate printer
 643                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
 644                 }
 645
 646                 if ( $this->mPrinter->getNeedsRawData() ) {
 647                         $this->getResult()->setRawMode();
 648                 }
 649         }
 650
 651         /**
 652          * Execute the actual module, without any error handling
 653          */
 654         protected function executeAction() {
 655                 $params = $this->setupExecuteAction();
 656                 $module = $this->setupModule();
 657
 658                 $this->checkExecutePermissions( $module );
 659
 660                 if ( !$this->checkMaxLag( $module, $params ) ) {
 661                         return;
 662                 }
 663
 664                 if ( !$this->mInternalMode ) {
 665                         $this->setupExternalResponse( $module, $params );
 666                 }
 667
 668                 // Execute
 669                 $module->profileIn();
 670                 $module->execute();
 671                 wfRunHooks( 'APIAfterExecute', array( &$module ) );
 672                 $module->profileOut();
 673
 674                 if ( !$this->mInternalMode ) {
 675                         // Print result data
 676                         $this->printResult( false );
 677                 }
 678         }
 679
 680         /**
 681          * Print results using the current printer
 682          *
 683          * @param $isError bool
 684          */
 685         protected function printResult( $isError ) {
 686                 $this->getResult()->cleanUpUTF8();
 687                 $printer = $this->mPrinter;
 688                 $printer->profileIn();
 689
 690                 /**
 691                  * If the help message is requested in the default (xmlfm) format,
 692                  * tell the printer not to escape ampersands so that our links do
 693                  * not break.
 694                  */
 695                 $printer->setUnescapeAmps( ( $this->mAction == 'help' || $isError )
 696                                 && $printer->getFormat() == 'XML' && $printer->getIsHtml() );
 697
 698                 $printer->initPrinter( $isError );
 699
 700                 $printer->execute();
 701                 $printer->closePrinter();
 702                 $printer->profileOut();
 703         }
 704
 705         /**
 706          * @return bool
 707          */
 708         public function isReadMode() {
 709                 return false;
 710         }
 711
 712         /**
 713          * See ApiBase for description.
 714          *
 715          * @return array
 716          */
 717         public function getAllowedParams() {
 718                 return array(
 719                         'format' => array(
 720                                 ApiBase::PARAM_DFLT => ApiMain::API_DEFAULT_FORMAT,
 721                                 ApiBase::PARAM_TYPE => $this->mFormatNames
 722                         ),
 723                         'action' => array(
 724                                 ApiBase::PARAM_DFLT => 'help',
 725                                 ApiBase::PARAM_TYPE => $this->mModuleNames
 726                         ),
 727                         'version' => false,
 728                         'maxlag'  => array(
 729                                 ApiBase::PARAM_TYPE => 'integer'
 730                         ),
 731                         'smaxage' => array(
 732                                 ApiBase::PARAM_TYPE => 'integer',
 733                                 ApiBase::PARAM_DFLT => 0
 734                         ),
 735                         'maxage' => array(
 736                                 ApiBase::PARAM_TYPE => 'integer',
 737                                 ApiBase::PARAM_DFLT => 0
 738                         ),
 739                         'requestid' => null,
 740                         'servedby'  => false,
 741                 );
 742         }
 743
 744         /**
 745          * See ApiBase for description.
 746          *
 747          * @return array
 748          */
 749         public function getParamDescription() {
 750                 return array(
 751                         'format' => 'The format of the output',
 752                         'action' => 'What action you would like to perform. See below for module help',
 753                         'version' => 'When showing help, include version for each module',
 754                         'maxlag' => array(
 755                                 'Maximum lag can be used when MediaWiki is installed on a database replicated cluster.',
 756                                 'To save actions causing any more site replication lag, this parameter can make the client',
 757                                 'wait until the replication lag is less than the specified value.',
 758                                 'In case of a replag error, a HTTP 503 error is returned, with the message like',
 759                                 '"Waiting for $host: $lag seconds lagged\n".',
 760                                 'See http://www.mediawiki.org/wiki/Manual:Maxlag_parameter for more information',
 761                         ),
 762                         'smaxage' => 'Set the s-maxage header to this many seconds. Errors are never cached',
 763                         'maxage' => 'Set the max-age header to this many seconds. Errors are never cached',
 764                         'requestid' => 'Request ID to distinguish requests. This will just be output back to you',
 765                         'servedby' => 'Include the hostname that served the request in the results. Unconditionally shown on error',
 766                 );
 767         }
 768
 769         /**
 770          * See ApiBase for description.
 771          *
 772          * @return array
 773          */
 774         public function getDescription() {
 775                 return array(
 776                         '',
 777                         '',
 778                         '**********************************************************************************************************',
 779                         '**                                                                                                      **',
 780                         '**                      This is an auto-generated MediaWiki API documentation page                      **',
 781                         '**                                                                                                      **',
 782                         '**                                    Documentation and Examples:                                       **',
 783                         '**                                 http://www.mediawiki.org/wiki/API                                    **',
 784                         '**                                                                                                      **',
 785                         '**********************************************************************************************************',
 786                         '',
 787                         'Status:                All features shown on this page should be working, but the API',
 788                         '                       is still in active development, and may change at any time.',
 789                         '                       Make sure to monitor our mailing list for any updates',
 790                         '',
 791                         'Erroneous requests:    When erroneous are sent to the API, a HTTP header will be sent',
 792                         '                       with the key "MediaWiki-API-Error" and then both the value of the',
 793                         '                       header and the error code sent back will be set to the same value',
 794                         '',
 795                         '                       In the case of an invalid action being passed, these will have a value',
 796                         '                       of "unknown_action"',
 797                         '',
 798                         'Documentation:         http://www.mediawiki.org/wiki/API',
 799                         'Mailing list:          http://lists.wikimedia.org/mailman/listinfo/mediawiki-api',
 800                         'Api Announcements:     http://lists.wikimedia.org/mailman/listinfo/mediawiki-api-announce',
 801                         'Bugs & Requests:       http://bugzilla.wikimedia.org/buglist.cgi?component=API&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&order=bugs.delta_ts',
 802                         '',
 803                         '',
 804                         '',
 805                         '',
 806                         '',
 807                 );
 808         }
 809
 810         /**
 811          * @return array
 812          */
 813         public function getPossibleErrors() {
 814                 return array_merge( parent::getPossibleErrors(), array(
 815                         array( 'readonlytext' ),
 816                         array( 'code' => 'unknown_format', 'info' => 'Unrecognized format: format' ),
 817                         array( 'code' => 'unknown_action', 'info' => 'The API requires a valid action parameter' ),
 818                         array( 'code' => 'maxlag', 'info' => 'Waiting for host: x seconds lagged' ),
 819                         array( 'code' => 'maxlag', 'info' => 'Waiting for a database server: x seconds lagged' ),
 820                 ) );
 821         }
 822
 823         /**
 824          * Returns an array of strings with credits for the API
 825          * @return array
 826          */
 827         protected function getCredits() {
 828                 return array(
 829                         'API developers:',
 830                         '    Roan Kattouw <Firstname>.<Lastname>@gmail.com (lead developer Sep 2007-present)',
 831                         '    Victor Vasiliev - vasilvv at gee mail dot com',
 832                         '    Bryan Tong Minh - bryan . tongminh @ gmail . com',
 833                         '    Sam Reed - sam @ reedyboy . net',
 834                         '    Yuri Astrakhan <Firstname><Lastname>@gmail.com (creator, lead developer Sep 2006-Sep 2007)',
 835                         '',
 836                         'Please send your comments, suggestions and questions to mediawiki-api@lists.wikimedia.org',
 837                         'or file a bug report at http://bugzilla.wikimedia.org/'
 838                 );
 839         }
 840
 841         /**
 842          * Sets whether the pretty-printer should format *bold* and $italics$
 843          *
 844          * @param $help bool
 845          */
 846         public function setHelp( $help = true ) {
 847                 $this->mPrinter->setHelp( $help );
 848         }
 849
 850         /**
 851          * Override the parent to generate help messages for all available modules.
 852          *
 853          * @return string
 854          */
 855         public function makeHelpMsg() {
 856                 global $wgMemc, $wgAPICacheHelpTimeout;
 857                 $this->setHelp();
 858                 // Get help text from cache if present
 859                 $key = wfMemcKey( 'apihelp', $this->getModuleName(),
 860                         SpecialVersion::getVersion( 'nodb' ) .
 861                         $this->getMain()->getShowVersions() );
 862                 if ( $wgAPICacheHelpTimeout > 0 ) {
 863                         $cached = $wgMemc->get( $key );
 864                         if ( $cached ) {
 865                                 return $cached;
 866                         }
 867                 }
 868                 $retval = $this->reallyMakeHelpMsg();
 869                 if ( $wgAPICacheHelpTimeout > 0 ) {
 870                         $wgMemc->set( $key, $retval, $wgAPICacheHelpTimeout );
 871                 }
 872                 return $retval;
 873         }
 874
 875         /**
 876          * @return mixed|string
 877          */
 878         public function reallyMakeHelpMsg() {
 879                 $this->setHelp();
 880
 881                 // Use parent to make default message for the main module
 882                 $msg = parent::makeHelpMsg();
 883
 884                 $astriks = str_repeat( '*** ', 14 );
 885                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
 886                 foreach ( array_keys( $this->mModules ) as $moduleName ) {
 887                         $module = new $this->mModules[$moduleName] ( $this, $moduleName );
 888                         $msg .= self::makeHelpMsgHeader( $module, 'action' );
 889                         $msg2 = $module->makeHelpMsg();
 890                         if ( $msg2 !== false ) {
 891                                 $msg .= $msg2;
 892                         }
 893                         $msg .= "\n";
 894                 }
 895
 896                 $msg .= "\n$astriks Permissions $astriks\n\n";
 897                 foreach ( self::$mRights as $right => $rightMsg ) {
 898                         $groups = User::getGroupsWithPermission( $right );
 899                         $msg .= "* " . $right . " *\n  " . wfMsgReplaceArgs( $rightMsg[ 'msg' ], $rightMsg[ 'params' ] ) .
 900                                                 "\nGranted to:\n  " . str_replace( '*', 'all', implode( ', ', $groups ) ) . "\n\n";
 901
 902                 }
 903
 904                 $msg .= "\n$astriks Formats  $astriks\n\n";
 905                 foreach ( array_keys( $this->mFormats ) as $formatName ) {
 906                         $module = $this->createPrinterByName( $formatName );
 907                         $msg .= self::makeHelpMsgHeader( $module, 'format' );
 908                         $msg2 = $module->makeHelpMsg();
 909                         if ( $msg2 !== false ) {
 910                                 $msg .= $msg2;
 911                         }
 912                         $msg .= "\n";
 913                 }
 914
 915                 $msg .= "\n*** Credits: ***\n   " . implode( "\n   ", $this->getCredits() ) . "\n";
 916
 917                 return $msg;
 918         }
 919
 920         /**
 921          * @param $module ApiBase
 922          * @param $paramName String What type of request is this? e.g. action, query, list, prop, meta, format
 923          * @return string
 924          */
 925         public static function makeHelpMsgHeader( $module, $paramName ) {
 926                 $modulePrefix = $module->getModulePrefix();
 927                 if ( strval( $modulePrefix ) !== '' ) {
 928                         $modulePrefix = "($modulePrefix) ";
 929                 }
 930
 931                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
 932         }
 933
 934         private $mCanApiHighLimits = null;
 935
 936         /**
 937          * Check whether the current user is allowed to use high limits
 938          * @return bool
 939          */
 940         public function canApiHighLimits() {
 941                 if ( !isset( $this->mCanApiHighLimits ) ) {
 942                         global $wgUser;
 943                         $this->mCanApiHighLimits = $wgUser->isAllowed( 'apihighlimits' );
 944                 }
 945
 946                 return $this->mCanApiHighLimits;
 947         }
 948
 949         /**
 950          * Check whether the user wants us to show version information in the API help
 951          * @return bool
 952          */
 953         public function getShowVersions() {
 954                 return $this->mShowVersions;
 955         }
 956
 957         /**
 958          * Returns the version information of this file, plus it includes
 959          * the versions for all files that are not callable proper API modules
 960          *
 961          * @return array
 962          */
 963         public function getVersion() {
 964                 $vers = array();
 965                 $vers[] = 'MediaWiki: ' . SpecialVersion::getVersion() . "\n    http://svn.wikimedia.org/viewvc/mediawiki/trunk/phase3/";
 966                 $vers[] = __CLASS__ . ': $Id$';
 967                 $vers[] = ApiBase::getBaseVersion();
 968                 $vers[] = ApiFormatBase::getBaseVersion();
 969                 $vers[] = ApiQueryBase::getBaseVersion();
 970                 return $vers;
 971         }
 972
 973         /**
 974          * Add or overwrite a module in this ApiMain instance. Intended for use by extending
 975          * classes who wish to add their own modules to their lexicon or override the
 976          * behavior of inherent ones.
 977          *
 978          * @param $mdlName String The identifier for this module.
 979          * @param $mdlClass String The class where this module is implemented.
 980          */
 981         protected function addModule( $mdlName, $mdlClass ) {
 982                 $this->mModules[$mdlName] = $mdlClass;
 983         }
 984
 985         /**
 986          * Add or overwrite an output format for this ApiMain. Intended for use by extending
 987          * classes who wish to add to or modify current formatters.
 988          *
 989          * @param $fmtName string The identifier for this format.
 990          * @param $fmtClass ApiFormatBase The class implementing this format.
 991          */
 992         protected function addFormat( $fmtName, $fmtClass ) {
 993                 $this->mFormats[$fmtName] = $fmtClass;
 994         }
 995
 996         /**
 997          * Get the array mapping module names to class names
 998          * @return array
 999          */
1000         function getModules() {
1001                 return $this->mModules;
1002         }
1003
1004         /**
1005          * Returns the list of supported formats in form ( 'format' => 'ClassName' )
1006          *
1007          * @since 1.18
1008          * @return array
1009          */
1010         public function getFormats() {
1011                 return $this->mFormats;
1012         }
1013 }
1014
1015 /**
1016  * This exception will be thrown when dieUsage is called to stop module execution.
1017  * The exception handling code will print a help screen explaining how this API may be used.
1018  *
1019  * @ingroup API
1020  */
1021 class UsageException extends Exception {
1022
1023         private $mCodestr;
1024         private $mExtraData;
1025
1026         public function __construct( $message, $codestr, $code = 0, $extradata = null ) {
1027                 parent::__construct( $message, $code );
1028                 $this->mCodestr = $codestr;
1029                 $this->mExtraData = $extradata;
1030         }
1031
1032         /**
1033          * @return string
1034          */
1035         public function getCodeString() {
1036                 return $this->mCodestr;
1037         }
1038
1039         /**
1040          * @return array
1041          */
1042         public function getMessageArray() {
1043                 $result = array(
1044                         'code' => $this->mCodestr,
1045                         'info' => $this->getMessage()
1046                 );
1047                 if ( is_array( $this->mExtraData ) ) {
1048                         $result = array_merge( $result, $this->mExtraData );
1049                 }
1050                 return $result;
1051         }
1052
1053         /**
1054          * @return string
1055          */
1056         public function __toString() {
1057                 return "{$this->getCodeString()}: {$this->getMessage()}";
1058         }
1059 }