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 /**
  29  * This is the main API class, used for both external and internal processing.
  30  * When executed, it will create the requested formatter object,
  31  * instantiate and execute an object associated with the needed action,
  32  * and use formatter to print results.
  33  * In case of an exception, an error message will be printed using the same formatter.
  34  *
  35  * To use API from another application, run it using FauxRequest object, in which
  36  * case any internal exceptions will not be handled but passed up to the caller.
  37  * After successful execution, use getResult() for the resulting data.
  38  *
  39  * @ingroup API
  40  */
  41 class ApiMain extends ApiBase {
  42
  43         /**
  44          * When no format parameter is given, this format will be used
  45          */
  46         const API_DEFAULT_FORMAT = 'xmlfm';
  47
  48         /**
  49          * List of available modules: action name => module class
  50          */
  51         private static $Modules = array(
  52                 'login' => 'ApiLogin',
  53                 'logout' => 'ApiLogout',
  54                 'query' => 'ApiQuery',
  55                 'expandtemplates' => 'ApiExpandTemplates',
  56                 'parse' => 'ApiParse',
  57                 'opensearch' => 'ApiOpenSearch',
  58                 'feedcontributions' => 'ApiFeedContributions',
  59                 'feedwatchlist' => 'ApiFeedWatchlist',
  60                 'help' => 'ApiHelp',
  61                 'paraminfo' => 'ApiParamInfo',
  62                 'rsd' => 'ApiRsd',
  63                 'compare' => 'ApiComparePages',
  64
  65                 // Write modules
  66                 'purge' => 'ApiPurge',
  67                 'rollback' => 'ApiRollback',
  68                 'delete' => 'ApiDelete',
  69                 'undelete' => 'ApiUndelete',
  70                 'protect' => 'ApiProtect',
  71                 'block' => 'ApiBlock',
  72                 'unblock' => 'ApiUnblock',
  73                 'move' => 'ApiMove',
  74                 'edit' => 'ApiEditPage',
  75                 'upload' => 'ApiUpload',
  76                 'filerevert' => 'ApiFileRevert',
  77                 'emailuser' => 'ApiEmailUser',
  78                 'watch' => 'ApiWatch',
  79                 'patrol' => 'ApiPatrol',
  80                 'import' => 'ApiImport',
  81                 'userrights' => 'ApiUserrights',
  82         );
  83
  84         /**
  85          * List of available formats: format name => format class
  86          */
  87         private static $Formats = array(
  88                 'json' => 'ApiFormatJson',
  89                 'jsonfm' => 'ApiFormatJson',
  90                 'php' => 'ApiFormatPhp',
  91                 'phpfm' => 'ApiFormatPhp',
  92                 'wddx' => 'ApiFormatWddx',
  93                 'wddxfm' => 'ApiFormatWddx',
  94                 'xml' => 'ApiFormatXml',
  95                 'xmlfm' => 'ApiFormatXml',
  96                 'yaml' => 'ApiFormatYaml',
  97                 'yamlfm' => 'ApiFormatYaml',
  98                 'rawfm' => 'ApiFormatJson',
  99                 'txt' => 'ApiFormatTxt',
 100                 'txtfm' => 'ApiFormatTxt',
 101                 'dbg' => 'ApiFormatDbg',
 102                 'dbgfm' => 'ApiFormatDbg',
 103                 'dump' => 'ApiFormatDump',
 104                 'dumpfm' => 'ApiFormatDump',
 105         );
 106
 107         /**
 108          * List of user roles that are specifically relevant to the API.
 109          * array( 'right' => array ( 'msg'    => 'Some message with a $1',
 110          *                           'params' => array ( $someVarToSubst ) ),
 111          *                          );
 112          */
 113         private static $mRights = array(
 114                 'writeapi' => array(
 115                         'msg' => 'Use of the write API',
 116                         'params' => array()
 117                 ),
 118                 'apihighlimits' => array(
 119                         '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.',
 120                         'params' => array( ApiBase::LIMIT_SML2, ApiBase::LIMIT_BIG2 )
 121                 )
 122         );
 123
 124         /**
 125          * @var ApiFormatBase
 126          */
 127         private $mPrinter;
 128
 129         private $mModules, $mModuleNames, $mFormats, $mFormatNames;
 130         private $mResult, $mAction, $mShowVersions, $mEnableWrite;
 131         private $mInternalMode, $mSquidMaxage, $mModule;
 132
 133         private $mCacheMode = 'private';
 134         private $mCacheControl = array();
 135
 136         /**
 137          * Constructs an instance of ApiMain that utilizes the module and format specified by $request.
 138          *
 139          * @param $context IContextSource|WebRequest - if this is an instance of FauxRequest, errors are thrown and no printing occurs
 140          * @param $enableWrite bool should be set to true if the api may modify data
 141          */
 142         public function __construct( $context = null, $enableWrite = false ) {
 143                 if ( $context === null ) {
 144                         $context = RequestContext::getMain();
 145                 } elseif ( $context instanceof WebRequest ) {
 146                         // BC for pre-1.19
 147                         $request = $context;
 148                         $context = RequestContext::getMain();
 149                 }
 150                 // We set a derivative context so we can change stuff later
 151                 $this->setContext( new DerivativeContext( $context ) );
 152
 153                 if ( isset( $request ) ) {
 154                         $this->getContext()->setRequest( $request );
 155                 }
 156
 157                 $this->mInternalMode = ( $this->getRequest() instanceof FauxRequest );
 158
 159                 // Special handling for the main module: $parent === $this
 160                 parent::__construct( $this, $this->mInternalMode ? 'main_int' : 'main' );
 161
 162                 if ( !$this->mInternalMode ) {
 163                         // Impose module restrictions.
 164                         // If the current user cannot read,
 165                         // Remove all modules other than login
 166                         global $wgUser;
 167
 168                         if ( $this->getRequest()->getVal( 'callback' ) !== null ) {
 169                                 // JSON callback allows cross-site reads.
 170                                 // For safety, strip user credentials.
 171                                 wfDebug( "API: stripping user credentials for JSON callback\n" );
 172                                 $wgUser = new User();
 173                                 $this->getContext()->setUser( $wgUser );
 174                         }
 175                 }
 176
 177                 global $wgAPIModules; // extension modules
 178                 $this->mModules = $wgAPIModules + self::$Modules;
 179
 180                 $this->mModuleNames = array_keys( $this->mModules );
 181                 $this->mFormats = self::$Formats;
 182                 $this->mFormatNames = array_keys( $this->mFormats );
 183
 184                 $this->mResult = new ApiResult( $this );
 185                 $this->mShowVersions = false;
 186                 $this->mEnableWrite = $enableWrite;
 187
 188                 $this->mSquidMaxage = - 1; // flag for executeActionWithErrorHandling()
 189                 $this->mCommit = false;
 190         }
 191
 192         /**
 193          * Return true if the API was started by other PHP code using FauxRequest
 194          * @return bool
 195          */
 196         public function isInternalMode() {
 197                 return $this->mInternalMode;
 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                 wfDeprecated( __METHOD__, '1.17' );
 290                 $this->setCacheMode( 'private' );
 291         }
 292
 293         /**
 294          * Set directives (key/value pairs) for the Cache-Control header.
 295          * Boolean values will be formatted as such, by including or omitting
 296          * without an equals sign.
 297          *
 298          * Cache control values set here will only be used if the cache mode is not
 299          * private, see setCacheMode().
 300          *
 301          * @param $directives array
 302          */
 303         public function setCacheControl( $directives ) {
 304                 $this->mCacheControl = $directives + $this->mCacheControl;
 305         }
 306
 307         /**
 308          * Make sure Vary: Cookie and friends are set. Use this when the output of a request
 309          * may be cached for anons but may not be cached for logged-in users.
 310          *
 311          * WARNING: This function must be called CONSISTENTLY for a given URL. This means that a
 312          * given URL must either always or never call this function; if it sometimes does and
 313          * sometimes doesn't, stuff will break.
 314          *
 315          * @deprecated since 1.17 Use setCacheMode( 'anon-public-user-private' )
 316          */
 317         public function setVaryCookie() {
 318                 wfDeprecated( __METHOD__, '1.17' );
 319                 $this->setCacheMode( 'anon-public-user-private' );
 320         }
 321
 322         /**
 323          * Create an instance of an output formatter by its name
 324          *
 325          * @param $format string
 326          *
 327          * @return ApiFormatBase
 328          */
 329         public function createPrinterByName( $format ) {
 330                 if ( !isset( $this->mFormats[$format] ) ) {
 331                         $this->dieUsage( "Unrecognized format: {$format}", 'unknown_format' );
 332                 }
 333                 return new $this->mFormats[$format] ( $this, $format );
 334         }
 335
 336         /**
 337          * Execute api request. Any errors will be handled if the API was called by the remote client.
 338          */
 339         public function execute() {
 340                 $this->profileIn();
 341                 if ( $this->mInternalMode ) {
 342                         $this->executeAction();
 343                 } else {
 344                         $this->executeActionWithErrorHandling();
 345                 }
 346
 347                 $this->profileOut();
 348         }
 349
 350         /**
 351          * Execute an action, and in case of an error, erase whatever partial results
 352          * have been accumulated, and replace it with an error message and a help screen.
 353          */
 354         protected function executeActionWithErrorHandling() {
 355                 // In case an error occurs during data output,
 356                 // clear the output buffer and print just the error information
 357                 ob_start();
 358
 359                 try {
 360                         $this->executeAction();
 361                 } catch ( Exception $e ) {
 362                         // Log it
 363                         if ( $e instanceof MWException ) {
 364                                 wfDebugLog( 'exception', $e->getLogMessage() );
 365                         }
 366
 367                         // Handle any kind of exception by outputing properly formatted error message.
 368                         // If this fails, an unhandled exception should be thrown so that global error
 369                         // handler will process and log it.
 370
 371                         $errCode = $this->substituteResultWithError( $e );
 372
 373                         // Error results should not be cached
 374                         $this->setCacheMode( 'private' );
 375
 376                         $response = $this->getRequest()->response();
 377                         $headerStr = 'MediaWiki-API-Error: ' . $errCode;
 378                         if ( $e->getCode() === 0 ) {
 379                                 $response->header( $headerStr );
 380                         } else {
 381                                 $response->header( $headerStr, true, $e->getCode() );
 382                         }
 383
 384                         // Reset and print just the error message
 385                         ob_clean();
 386
 387                         // If the error occured during printing, do a printer->profileOut()
 388                         $this->mPrinter->safeProfileOut();
 389                         $this->printResult( true );
 390                 }
 391
 392                 // Send cache headers after any code which might generate an error, to
 393                 // avoid sending public cache headers for errors.
 394                 $this->sendCacheHeaders();
 395
 396                 if ( $this->mPrinter->getIsHtml() && !$this->mPrinter->isDisabled() ) {
 397                         echo wfReportTime();
 398                 }
 399
 400                 ob_end_flush();
 401         }
 402
 403         protected function sendCacheHeaders() {
 404                 global $wgUseXVO, $wgVaryOnXFP;
 405                 $response = $this->getRequest()->response();
 406
 407                 if ( $this->mCacheMode == 'private' ) {
 408                         $response->header( 'Cache-Control: private' );
 409                         return;
 410                 }
 411
 412                 if ( $this->mCacheMode == 'anon-public-user-private' ) {
 413                         $xfp = $wgVaryOnXFP ? ', X-Forwarded-Proto' : '';
 414                         $response->header( 'Vary: Accept-Encoding, Cookie' . $xfp );
 415                         if ( $wgUseXVO ) {
 416                                 $out = $this->getOutput();
 417                                 if ( $wgVaryOnXFP ) {
 418                                         $out->addVaryHeader( 'X-Forwarded-Proto' );
 419                                 }
 420                                 $response->header( $out->getXVO() );
 421                                 if ( $out->haveCacheVaryCookies() ) {
 422                                         // Logged in, mark this request private
 423                                         $response->header( 'Cache-Control: private' );
 424                                         return;
 425                                 }
 426                                 // Logged out, send normal public headers below
 427                         } elseif ( session_id() != '' ) {
 428                                 // Logged in or otherwise has session (e.g. anonymous users who have edited)
 429                                 // Mark request private
 430                                 $response->header( 'Cache-Control: private' );
 431                                 return;
 432                         } // else no XVO and anonymous, send public headers below
 433                 }
 434
 435                 // Send public headers
 436                 if ( $wgVaryOnXFP ) {
 437                         $response->header( 'Vary: Accept-Encoding, X-Forwarded-Proto' );
 438                         if ( $wgUseXVO ) {
 439                                 // Bleeeeegh. Our header setting system sucks
 440                                 $response->header( 'X-Vary-Options: Accept-Encoding;list-contains=gzip, X-Forwarded-Proto' );
 441                         }
 442                 }
 443
 444                 // If nobody called setCacheMaxAge(), use the (s)maxage parameters
 445                 if ( !isset( $this->mCacheControl['s-maxage'] ) ) {
 446                         $this->mCacheControl['s-maxage'] = $this->getParameter( 'smaxage' );
 447                 }
 448                 if ( !isset( $this->mCacheControl['max-age'] ) ) {
 449                         $this->mCacheControl['max-age'] = $this->getParameter( 'maxage' );
 450                 }
 451
 452                 if ( !$this->mCacheControl['s-maxage'] && !$this->mCacheControl['max-age'] ) {
 453                         // Public cache not requested
 454                         // Sending a Vary header in this case is harmless, and protects us
 455                         // against conditional calls of setCacheMaxAge().
 456                         $response->header( 'Cache-Control: private' );
 457                         return;
 458                 }
 459
 460                 $this->mCacheControl['public'] = true;
 461
 462                 // Send an Expires header
 463                 $maxAge = min( $this->mCacheControl['s-maxage'], $this->mCacheControl['max-age'] );
 464                 $expiryUnixTime = ( $maxAge == 0 ? 1 : time() + $maxAge );
 465                 $response->header( 'Expires: ' . wfTimestamp( TS_RFC2822, $expiryUnixTime ) );
 466
 467                 // Construct the Cache-Control header
 468                 $ccHeader = '';
 469                 $separator = '';
 470                 foreach ( $this->mCacheControl as $name => $value ) {
 471                         if ( is_bool( $value ) ) {
 472                                 if ( $value ) {
 473                                         $ccHeader .= $separator . $name;
 474                                         $separator = ', ';
 475                                 }
 476                         } else {
 477                                 $ccHeader .= $separator . "$name=$value";
 478                                 $separator = ', ';
 479                         }
 480                 }
 481
 482                 $response->header( "Cache-Control: $ccHeader" );
 483         }
 484
 485         /**
 486          * Replace the result data with the information about an exception.
 487          * Returns the error code
 488          * @param $e Exception
 489          * @return string
 490          */
 491         protected function substituteResultWithError( $e ) {
 492                 global $wgShowHostnames;
 493
 494                 $result = $this->getResult();
 495                 // Printer may not be initialized if the extractRequestParams() fails for the main module
 496                 if ( !isset ( $this->mPrinter ) ) {
 497                         // The printer has not been created yet. Try to manually get formatter value.
 498                         $value = $this->getRequest()->getVal( 'format', self::API_DEFAULT_FORMAT );
 499                         if ( !in_array( $value, $this->mFormatNames ) ) {
 500                                 $value = self::API_DEFAULT_FORMAT;
 501                         }
 502
 503                         $this->mPrinter = $this->createPrinterByName( $value );
 504                         if ( $this->mPrinter->getNeedsRawData() ) {
 505                                 $result->setRawMode();
 506                         }
 507                 }
 508
 509                 if ( $e instanceof UsageException ) {
 510                         // User entered incorrect parameters - print usage screen
 511                         $errMessage = $e->getMessageArray();
 512
 513                         // Only print the help message when this is for the developer, not runtime
 514                         if ( $this->mPrinter->getWantsHelp() || $this->mAction == 'help' ) {
 515                                 ApiResult::setContent( $errMessage, $this->makeHelpMsg() );
 516                         }
 517
 518                 } else {
 519                         global $wgShowSQLErrors, $wgShowExceptionDetails;
 520                         // Something is seriously wrong
 521                         if ( ( $e instanceof DBQueryError ) && !$wgShowSQLErrors ) {
 522                                 $info = 'Database query error';
 523                         } else {
 524                                 $info = "Exception Caught: {$e->getMessage()}";
 525                         }
 526
 527                         $errMessage = array(
 528                                 'code' => 'internal_api_error_' . get_class( $e ),
 529                                 'info' => $info,
 530                         );
 531                         ApiResult::setContent( $errMessage, $wgShowExceptionDetails ? "\n\n{$e->getTraceAsString()}\n\n" : '' );
 532                 }
 533
 534                 $result->reset();
 535                 $result->disableSizeCheck();
 536                 // Re-add the id
 537                 $requestid = $this->getParameter( 'requestid' );
 538                 if ( !is_null( $requestid ) ) {
 539                         $result->addValue( null, 'requestid', $requestid );
 540                 }
 541
 542                 if ( $wgShowHostnames ) {
 543                         // servedby is especially useful when debugging errors
 544                         $result->addValue( null, 'servedby', wfHostName() );
 545                 }
 546
 547                 $result->addValue( null, 'error', $errMessage );
 548
 549                 return $errMessage['code'];
 550         }
 551
 552         /**
 553          * Set up for the execution.
 554          * @return array
 555          */
 556         protected function setupExecuteAction() {
 557                 global $wgShowHostnames;
 558
 559                 // First add the id to the top element
 560                 $result = $this->getResult();
 561                 $requestid = $this->getParameter( 'requestid' );
 562                 if ( !is_null( $requestid ) ) {
 563                         $result->addValue( null, 'requestid', $requestid );
 564                 }
 565
 566                 if ( $wgShowHostnames ) {
 567                         $servedby = $this->getParameter( 'servedby' );
 568                         if ( $servedby ) {
 569                                 $result->addValue( null, 'servedby', wfHostName() );
 570                         }
 571                 }
 572
 573                 $params = $this->extractRequestParams();
 574
 575                 $this->mShowVersions = $params['version'];
 576                 $this->mAction = $params['action'];
 577
 578                 if ( !is_string( $this->mAction ) ) {
 579                         $this->dieUsage( 'The API requires a valid action parameter', 'unknown_action' );
 580                 }
 581
 582                 return $params;
 583         }
 584
 585         /**
 586          * Set up the module for response
 587          * @return ApiBase The module that will handle this action
 588          */
 589         protected function setupModule() {
 590                 // Instantiate the module requested by the user
 591                 $module = new $this->mModules[$this->mAction] ( $this, $this->mAction );
 592                 $this->mModule = $module;
 593
 594                 $moduleParams = $module->extractRequestParams();
 595
 596                 // Die if token required, but not provided (unless there is a gettoken parameter)
 597                 $salt = $module->getTokenSalt();
 598                 if ( $salt !== false && !$moduleParams['gettoken'] ) {
 599                         if ( !isset( $moduleParams['token'] ) ) {
 600                                 $this->dieUsageMsg( array( 'missingparam', 'token' ) );
 601                         } else {
 602                                 if ( !$this->getUser()->matchEditToken( $moduleParams['token'], $salt, $this->getRequest() ) ) {
 603                                         $this->dieUsageMsg( 'sessionfailure' );
 604                                 }
 605                         }
 606                 }
 607                 return $module;
 608         }
 609
 610         /**
 611          * Check the max lag if necessary
 612          * @param $module ApiBase object: Api module being used
 613          * @param $params Array an array containing the request parameters.
 614          * @return boolean True on success, false should exit immediately
 615          */
 616         protected function checkMaxLag( $module, $params ) {
 617                 if ( $module->shouldCheckMaxlag() && isset( $params['maxlag'] ) ) {
 618                         // Check for maxlag
 619                         global $wgShowHostnames;
 620                         $maxLag = $params['maxlag'];
 621                         list( $host, $lag ) = wfGetLB()->getMaxLag();
 622                         if ( $lag > $maxLag ) {
 623                                 $response = $this->getRequest()->response();
 624
 625                                 $response->header( 'Retry-After: ' . max( intval( $maxLag ), 5 ) );
 626                                 $response->header( 'X-Database-Lag: ' . intval( $lag ) );
 627
 628                                 if ( $wgShowHostnames ) {
 629                                         $this->dieUsage( "Waiting for $host: $lag seconds lagged", 'maxlag' );
 630                                 } else {
 631                                         $this->dieUsage( "Waiting for a database server: $lag seconds lagged", 'maxlag' );
 632                                 }
 633                                 return false;
 634                         }
 635                 }
 636                 return true;
 637         }
 638
 639         /**
 640          * Check for sufficient permissions to execute
 641          * @param $module ApiBase An Api module
 642          */
 643         protected function checkExecutePermissions( $module ) {
 644                 $user = $this->getUser();
 645                 if ( $module->isReadMode() && !in_array( 'read', User::getGroupPermissions( array( '*' ) ), true ) &&
 646                         !$user->isAllowed( 'read' ) )
 647                 {
 648                         $this->dieUsageMsg( 'readrequired' );
 649                 }
 650                 if ( $module->isWriteMode() ) {
 651                         if ( !$this->mEnableWrite ) {
 652                                 $this->dieUsageMsg( 'writedisabled' );
 653                         }
 654                         if ( !$user->isAllowed( 'writeapi' ) ) {
 655                                 $this->dieUsageMsg( 'writerequired' );
 656                         }
 657                         if ( wfReadOnly() ) {
 658                                 $this->dieReadOnly();
 659                         }
 660                 }
 661         }
 662
 663         /**
 664          * Check POST for external response and setup result printer
 665          * @param $module ApiBase An Api module
 666          * @param $params Array an array with the request parameters
 667          */
 668         protected function setupExternalResponse( $module, $params ) {
 669                 // Ignore mustBePosted() for internal calls
 670                 if ( $module->mustBePosted() && !$this->getRequest()->wasPosted() ) {
 671                         $this->dieUsageMsg( array( 'mustbeposted', $this->mAction ) );
 672                 }
 673
 674                 // See if custom printer is used
 675                 $this->mPrinter = $module->getCustomPrinter();
 676                 if ( is_null( $this->mPrinter ) ) {
 677                         // Create an appropriate printer
 678                         $this->mPrinter = $this->createPrinterByName( $params['format'] );
 679                 }
 680
 681                 if ( $this->mPrinter->getNeedsRawData() ) {
 682                         $this->getResult()->setRawMode();
 683                 }
 684         }
 685
 686         /**
 687          * Execute the actual module, without any error handling
 688          */
 689         protected function executeAction() {
 690                 $params = $this->setupExecuteAction();
 691                 $module = $this->setupModule();
 692
 693                 $this->checkExecutePermissions( $module );
 694
 695                 if ( !$this->checkMaxLag( $module, $params ) ) {
 696                         return;
 697                 }
 698
 699                 if ( !$this->mInternalMode ) {
 700                         $this->setupExternalResponse( $module, $params );
 701                 }
 702
 703                 // Execute
 704                 $module->profileIn();
 705                 $module->execute();
 706                 wfRunHooks( 'APIAfterExecute', array( &$module ) );
 707                 $module->profileOut();
 708
 709                 if ( !$this->mInternalMode ) {
 710                         // Print result data
 711                         $this->printResult( false );
 712                 }
 713         }
 714
 715         /**
 716          * Print results using the current printer
 717          *
 718          * @param $isError bool
 719          */
 720         protected function printResult( $isError ) {
 721                 $this->getResult()->cleanUpUTF8();
 722                 $printer = $this->mPrinter;
 723                 $printer->profileIn();
 724
 725                 /**
 726                  * If the help message is requested in the default (xmlfm) format,
 727                  * tell the printer not to escape ampersands so that our links do
 728                  * not break.
 729                  */
 730                 $printer->setUnescapeAmps( ( $this->mAction == 'help' || $isError )
 731                                 && $printer->getFormat() == 'XML' && $printer->getIsHtml() );
 732
 733                 $printer->initPrinter( $isError );
 734
 735                 $printer->execute();
 736                 $printer->closePrinter();
 737                 $printer->profileOut();
 738         }
 739
 740         /**
 741          * @return bool
 742          */
 743         public function isReadMode() {
 744                 return false;
 745         }
 746
 747         /**
 748          * See ApiBase for description.
 749          *
 750          * @return array
 751          */
 752         public function getAllowedParams() {
 753                 return array(
 754                         'format' => array(
 755                                 ApiBase::PARAM_DFLT => ApiMain::API_DEFAULT_FORMAT,
 756                                 ApiBase::PARAM_TYPE => $this->mFormatNames
 757                         ),
 758                         'action' => array(
 759                                 ApiBase::PARAM_DFLT => 'help',
 760                                 ApiBase::PARAM_TYPE => $this->mModuleNames
 761                         ),
 762                         'version' => false,
 763                         'maxlag'  => array(
 764                                 ApiBase::PARAM_TYPE => 'integer'
 765                         ),
 766                         'smaxage' => array(
 767                                 ApiBase::PARAM_TYPE => 'integer',
 768                                 ApiBase::PARAM_DFLT => 0
 769                         ),
 770                         'maxage' => array(
 771                                 ApiBase::PARAM_TYPE => 'integer',
 772                                 ApiBase::PARAM_DFLT => 0
 773                         ),
 774                         'requestid' => null,
 775                         'servedby'  => false,
 776                 );
 777         }
 778
 779         /**
 780          * See ApiBase for description.
 781          *
 782          * @return array
 783          */
 784         public function getParamDescription() {
 785                 return array(
 786                         'format' => 'The format of the output',
 787                         'action' => 'What action you would like to perform. See below for module help',
 788                         'version' => 'When showing help, include version for each module',
 789                         'maxlag' => array(
 790                                 'Maximum lag can be used when MediaWiki is installed on a database replicated cluster.',
 791                                 'To save actions causing any more site replication lag, this parameter can make the client',
 792                                 'wait until the replication lag is less than the specified value.',
 793                                 'In case of a replag error, a HTTP 503 error is returned, with the message like',
 794                                 '"Waiting for $host: $lag seconds lagged\n".',
 795                                 'See https://www.mediawiki.org/wiki/Manual:Maxlag_parameter for more information',
 796                         ),
 797                         'smaxage' => 'Set the s-maxage header to this many seconds. Errors are never cached',
 798                         'maxage' => 'Set the max-age header to this many seconds. Errors are never cached',
 799                         'requestid' => 'Request ID to distinguish requests. This will just be output back to you',
 800                         'servedby' => 'Include the hostname that served the request in the results. Unconditionally shown on error',
 801                 );
 802         }
 803
 804         /**
 805          * See ApiBase for description.
 806          *
 807          * @return array
 808          */
 809         public function getDescription() {
 810                 return array(
 811                         '',
 812                         '',
 813                         '**********************************************************************************************************',
 814                         '**                                                                                                      **',
 815                         '**                      This is an auto-generated MediaWiki API documentation page                      **',
 816                         '**                                                                                                      **',
 817                         '**                                     Documentation and Examples:                                      **',
 818                         '**                                  https://www.mediawiki.org/wiki/API                                  **',
 819                         '**                                                                                                      **',
 820                         '**********************************************************************************************************',
 821                         '',
 822                         'Status:                All features shown on this page should be working, but the API',
 823                         '                       is still in active development, and may change at any time.',
 824                         '                       Make sure to monitor our mailing list for any updates',
 825                         '',
 826                         'Erroneous requests:    When erroneous requests are sent to the API, a HTTP header will be sent',
 827                         '                       with the key "MediaWiki-API-Error" and then both the value of the',
 828                         '                       header and the error code sent back will be set to the same value',
 829                         '',
 830                         '                       In the case of an invalid action being passed, these will have a value',
 831                         '                       of "unknown_action"',
 832                         '',
 833                         '                       For more information see https://www.mediawiki.org/wiki/API:Errors_and_warnings',
 834                         '',
 835                         'Documentation:         https://www.mediawiki.org/wiki/API:Main_page',
 836                         'FAQ                    https://www.mediawiki.org/wiki/API:FAQ',
 837                         'Mailing list:          https://lists.wikimedia.org/mailman/listinfo/mediawiki-api',
 838                         'Api Announcements:     https://lists.wikimedia.org/mailman/listinfo/mediawiki-api-announce',
 839                         'Bugs & Requests:       https://bugzilla.wikimedia.org/buglist.cgi?component=API&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&order=bugs.delta_ts',
 840                         '',
 841                         '',
 842                         '',
 843                         '',
 844                         '',
 845                 );
 846         }
 847
 848         /**
 849          * @return array
 850          */
 851         public function getPossibleErrors() {
 852                 return array_merge( parent::getPossibleErrors(), array(
 853                         array( 'readonlytext' ),
 854                         array( 'code' => 'unknown_format', 'info' => 'Unrecognized format: format' ),
 855                         array( 'code' => 'unknown_action', 'info' => 'The API requires a valid action parameter' ),
 856                         array( 'code' => 'maxlag', 'info' => 'Waiting for host: x seconds lagged' ),
 857                         array( 'code' => 'maxlag', 'info' => 'Waiting for a database server: x seconds lagged' ),
 858                 ) );
 859         }
 860
 861         /**
 862          * Returns an array of strings with credits for the API
 863          * @return array
 864          */
 865         protected function getCredits() {
 866                 return array(
 867                         'API developers:',
 868                         '    Roan Kattouw <Firstname>.<Lastname>@gmail.com (lead developer Sep 2007-present)',
 869                         '    Victor Vasiliev - vasilvv at gee mail dot com',
 870                         '    Bryan Tong Minh - bryan . tongminh @ gmail . com',
 871                         '    Sam Reed - sam @ reedyboy . net',
 872                         '    Yuri Astrakhan <Firstname><Lastname>@gmail.com (creator, lead developer Sep 2006-Sep 2007)',
 873                         '',
 874                         'Please send your comments, suggestions and questions to mediawiki-api@lists.wikimedia.org',
 875                         'or file a bug report at https://bugzilla.wikimedia.org/'
 876                 );
 877         }
 878
 879         /**
 880          * Sets whether the pretty-printer should format *bold* and $italics$
 881          *
 882          * @param $help bool
 883          */
 884         public function setHelp( $help = true ) {
 885                 $this->mPrinter->setHelp( $help );
 886         }
 887
 888         /**
 889          * Override the parent to generate help messages for all available modules.
 890          *
 891          * @return string
 892          */
 893         public function makeHelpMsg() {
 894                 global $wgMemc, $wgAPICacheHelpTimeout;
 895                 $this->setHelp();
 896                 // Get help text from cache if present
 897                 $key = wfMemcKey( 'apihelp', $this->getModuleName(),
 898                         SpecialVersion::getVersion( 'nodb' ) .
 899                         $this->getShowVersions() );
 900                 if ( $wgAPICacheHelpTimeout > 0 ) {
 901                         $cached = $wgMemc->get( $key );
 902                         if ( $cached ) {
 903                                 return $cached;
 904                         }
 905                 }
 906                 $retval = $this->reallyMakeHelpMsg();
 907                 if ( $wgAPICacheHelpTimeout > 0 ) {
 908                         $wgMemc->set( $key, $retval, $wgAPICacheHelpTimeout );
 909                 }
 910                 return $retval;
 911         }
 912
 913         /**
 914          * @return mixed|string
 915          */
 916         public function reallyMakeHelpMsg() {
 917                 $this->setHelp();
 918
 919                 // Use parent to make default message for the main module
 920                 $msg = parent::makeHelpMsg();
 921
 922                 $astriks = str_repeat( '*** ', 14 );
 923                 $msg .= "\n\n$astriks Modules  $astriks\n\n";
 924                 foreach ( array_keys( $this->mModules ) as $moduleName ) {
 925                         $module = new $this->mModules[$moduleName] ( $this, $moduleName );
 926                         $msg .= self::makeHelpMsgHeader( $module, 'action' );
 927                         $msg2 = $module->makeHelpMsg();
 928                         if ( $msg2 !== false ) {
 929                                 $msg .= $msg2;
 930                         }
 931                         $msg .= "\n";
 932                 }
 933
 934                 $msg .= "\n$astriks Permissions $astriks\n\n";
 935                 foreach ( self::$mRights as $right => $rightMsg ) {
 936                         $groups = User::getGroupsWithPermission( $right );
 937                         $msg .= "* " . $right . " *\n  " . wfMsgReplaceArgs( $rightMsg[ 'msg' ], $rightMsg[ 'params' ] ) .
 938                                                 "\nGranted to:\n  " . str_replace( '*', 'all', implode( ', ', $groups ) ) . "\n\n";
 939
 940                 }
 941
 942                 $msg .= "\n$astriks Formats  $astriks\n\n";
 943                 foreach ( array_keys( $this->mFormats ) as $formatName ) {
 944                         $module = $this->createPrinterByName( $formatName );
 945                         $msg .= self::makeHelpMsgHeader( $module, 'format' );
 946                         $msg2 = $module->makeHelpMsg();
 947                         if ( $msg2 !== false ) {
 948                                 $msg .= $msg2;
 949                         }
 950                         $msg .= "\n";
 951                 }
 952
 953                 $msg .= "\n*** Credits: ***\n   " . implode( "\n   ", $this->getCredits() ) . "\n";
 954
 955                 return $msg;
 956         }
 957
 958         /**
 959          * @param $module ApiBase
 960          * @param $paramName String What type of request is this? e.g. action, query, list, prop, meta, format
 961          * @return string
 962          */
 963         public static function makeHelpMsgHeader( $module, $paramName ) {
 964                 $modulePrefix = $module->getModulePrefix();
 965                 if ( strval( $modulePrefix ) !== '' ) {
 966                         $modulePrefix = "($modulePrefix) ";
 967                 }
 968
 969                 return "* $paramName={$module->getModuleName()} $modulePrefix*";
 970         }
 971
 972         private $mCanApiHighLimits = null;
 973
 974         /**
 975          * Check whether the current user is allowed to use high limits
 976          * @return bool
 977          */
 978         public function canApiHighLimits() {
 979                 if ( !isset( $this->mCanApiHighLimits ) ) {
 980                         $this->mCanApiHighLimits = $this->getUser()->isAllowed( 'apihighlimits' );
 981                 }
 982
 983                 return $this->mCanApiHighLimits;
 984         }
 985
 986         /**
 987          * Check whether the user wants us to show version information in the API help
 988          * @return bool
 989          */
 990         public function getShowVersions() {
 991                 return $this->mShowVersions;
 992         }
 993
 994         /**
 995          * Returns the version information of this file, plus it includes
 996          * the versions for all files that are not callable proper API modules
 997          *
 998          * @return array
 999          */
1000         public function getVersion() {
1001                 $vers = array();
1002                 $vers[] = 'MediaWiki: ' . SpecialVersion::getVersion() . "\n    https://svn.wikimedia.org/viewvc/mediawiki/trunk/phase3/";
1003                 $vers[] = __CLASS__ . ': $Id$';
1004                 $vers[] = ApiBase::getBaseVersion();
1005                 $vers[] = ApiFormatBase::getBaseVersion();
1006                 $vers[] = ApiQueryBase::getBaseVersion();
1007                 return $vers;
1008         }
1009
1010         /**
1011          * Add or overwrite a module in this ApiMain instance. Intended for use by extending
1012          * classes who wish to add their own modules to their lexicon or override the
1013          * behavior of inherent ones.
1014          *
1015          * @param $mdlName String The identifier for this module.
1016          * @param $mdlClass String The class where this module is implemented.
1017          */
1018         protected function addModule( $mdlName, $mdlClass ) {
1019                 $this->mModules[$mdlName] = $mdlClass;
1020         }
1021
1022         /**
1023          * Add or overwrite an output format for this ApiMain. Intended for use by extending
1024          * classes who wish to add to or modify current formatters.
1025          *
1026          * @param $fmtName string The identifier for this format.
1027          * @param $fmtClass ApiFormatBase The class implementing this format.
1028          */
1029         protected function addFormat( $fmtName, $fmtClass ) {
1030                 $this->mFormats[$fmtName] = $fmtClass;
1031         }
1032
1033         /**
1034          * Get the array mapping module names to class names
1035          * @return array
1036          */
1037         function getModules() {
1038                 return $this->mModules;
1039         }
1040
1041         /**
1042          * Returns the list of supported formats in form ( 'format' => 'ClassName' )
1043          *
1044          * @since 1.18
1045          * @return array
1046          */
1047         public function getFormats() {
1048                 return $this->mFormats;
1049         }
1050 }
1051
1052 /**
1053  * This exception will be thrown when dieUsage is called to stop module execution.
1054  * The exception handling code will print a help screen explaining how this API may be used.
1055  *
1056  * @ingroup API
1057  */
1058 class UsageException extends MWException {
1059
1060         private $mCodestr;
1061         private $mExtraData;
1062
1063         public function __construct( $message, $codestr, $code = 0, $extradata = null ) {
1064                 parent::__construct( $message, $code );
1065                 $this->mCodestr = $codestr;
1066                 $this->mExtraData = $extradata;
1067         }
1068
1069         /**
1070          * @return string
1071          */
1072         public function getCodeString() {
1073                 return $this->mCodestr;
1074         }
1075
1076         /**
1077          * @return array
1078          */
1079         public function getMessageArray() {
1080                 $result = array(
1081                         'code' => $this->mCodestr,
1082                         'info' => $this->getMessage()
1083                 );
1084                 if ( is_array( $this->mExtraData ) ) {
1085                         $result = array_merge( $result, $this->mExtraData );
1086                 }
1087                 return $result;
1088         }
1089
1090         /**
1091          * @return string
1092          */
1093         public function __toString() {
1094                 return "{$this->getCodeString()}: {$this->getMessage()}";
1095         }
1096 }