includes/context/RequestContext.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @since 1.18
  19  *
  20  * @author Alexandre Emsenhuber
  21  * @author Daniel Friesen
  22  * @file
  23  */
  24
  25 use MediaWiki\Logger\LoggerFactory;
  26 use MediaWiki\MediaWikiServices;
  27 use Wikimedia\ScopedCallback;
  28
  29 /**
  30  * Group all the pieces relevant to the context of a request into one instance
  31  */
  32 class RequestContext implements IContextSource, MutableContext {
  33         /**
  34          * @var WebRequest
  35          */
  36         private $request;
  37
  38         /**
  39          * @var Title
  40          */
  41         private $title;
  42
  43         /**
  44          * @var WikiPage
  45          */
  46         private $wikipage;
  47
  48         /**
  49          * @var OutputPage
  50          */
  51         private $output;
  52
  53         /**
  54          * @var User
  55          */
  56         private $user;
  57
  58         /**
  59          * @var Language
  60          */
  61         private $lang;
  62
  63         /**
  64          * @var Skin
  65          */
  66         private $skin;
  67
  68         /**
  69          * @var Timing
  70          */
  71         private $timing;
  72
  73         /**
  74          * @var Config
  75          */
  76         private $config;
  77
  78         /**
  79          * @var RequestContext
  80          */
  81         private static $instance = null;
  82
  83         /**
  84          * Set the Config object
  85          *
  86          * @param Config $c
  87          */
  88         public function setConfig( Config $c ) {
  89                 $this->config = $c;
  90         }
  91
  92         /**
  93          * Get the Config object
  94          *
  95          * @return Config
  96          */
  97         public function getConfig() {
  98                 if ( $this->config === null ) {
  99                         // @todo In the future, we could move this to WebStart.php so
 100                         // the Config object is ready for when initialization happens
 101                         $this->config = MediaWikiServices::getInstance()->getMainConfig();
 102                 }
 103
 104                 return $this->config;
 105         }
 106
 107         /**
 108          * Set the WebRequest object
 109          *
 110          * @param WebRequest $r
 111          */
 112         public function setRequest( WebRequest $r ) {
 113                 $this->request = $r;
 114         }
 115
 116         /**
 117          * Get the WebRequest object
 118          *
 119          * @return WebRequest
 120          */
 121         public function getRequest() {
 122                 if ( $this->request === null ) {
 123                         global $wgCommandLineMode;
 124                         // create the WebRequest object on the fly
 125                         if ( $wgCommandLineMode ) {
 126                                 $this->request = new FauxRequest( [] );
 127                         } else {
 128                                 $this->request = new WebRequest();
 129                         }
 130                 }
 131
 132                 return $this->request;
 133         }
 134
 135         /**
 136          * Get the Stats object
 137          *
 138          * @deprecated since 1.27 use a StatsdDataFactory from MediaWikiServices (preferably injected)
 139          *
 140          * @return IBufferingStatsdDataFactory
 141          */
 142         public function getStats() {
 143                 return MediaWikiServices::getInstance()->getStatsdDataFactory();
 144         }
 145
 146         /**
 147          * Get the timing object
 148          *
 149          * @return Timing
 150          */
 151         public function getTiming() {
 152                 if ( $this->timing === null ) {
 153                         $this->timing = new Timing( [
 154                                 'logger' => LoggerFactory::getInstance( 'Timing' )
 155                         ] );
 156                 }
 157                 return $this->timing;
 158         }
 159
 160         /**
 161          * Set the Title object
 162          *
 163          * @param Title|null $title
 164          */
 165         public function setTitle( Title $title = null ) {
 166                 $this->title = $title;
 167                 // Erase the WikiPage so a new one with the new title gets created.
 168                 $this->wikipage = null;
 169         }
 170
 171         /**
 172          * Get the Title object
 173          *
 174          * @return Title|null
 175          */
 176         public function getTitle() {
 177                 if ( $this->title === null ) {
 178                         global $wgTitle; # fallback to $wg till we can improve this
 179                         $this->title = $wgTitle;
 180                         wfDebugLog(
 181                                 'GlobalTitleFail',
 182                                 __METHOD__ . ' called by ' . wfGetAllCallers( 5 ) . ' with no title set.'
 183                         );
 184                 }
 185
 186                 return $this->title;
 187         }
 188
 189         /**
 190          * Check, if a Title object is set
 191          *
 192          * @since 1.25
 193          * @return bool
 194          */
 195         public function hasTitle() {
 196                 return $this->title !== null;
 197         }
 198
 199         /**
 200          * Check whether a WikiPage object can be get with getWikiPage().
 201          * Callers should expect that an exception is thrown from getWikiPage()
 202          * if this method returns false.
 203          *
 204          * @since 1.19
 205          * @return bool
 206          */
 207         public function canUseWikiPage() {
 208                 if ( $this->wikipage ) {
 209                         // If there's a WikiPage object set, we can for sure get it
 210                         return true;
 211                 }
 212                 // Only pages with legitimate titles can have WikiPages.
 213                 // That usually means pages in non-virtual namespaces.
 214                 $title = $this->getTitle();
 215                 return $title ? $title->canExist() : false;
 216         }
 217
 218         /**
 219          * Set the WikiPage object
 220          *
 221          * @since 1.19
 222          * @param WikiPage $p
 223          */
 224         public function setWikiPage( WikiPage $p ) {
 225                 $pageTitle = $p->getTitle();
 226                 if ( !$this->hasTitle() || !$pageTitle->equals( $this->getTitle() ) ) {
 227                         $this->setTitle( $pageTitle );
 228                 }
 229                 // Defer this to the end since setTitle sets it to null.
 230                 $this->wikipage = $p;
 231         }
 232
 233         /**
 234          * Get the WikiPage object.
 235          * May throw an exception if there's no Title object set or the Title object
 236          * belongs to a special namespace that doesn't have WikiPage, so use first
 237          * canUseWikiPage() to check whether this method can be called safely.
 238          *
 239          * @since 1.19
 240          * @throws MWException
 241          * @return WikiPage
 242          */
 243         public function getWikiPage() {
 244                 if ( $this->wikipage === null ) {
 245                         $title = $this->getTitle();
 246                         if ( $title === null ) {
 247                                 throw new MWException( __METHOD__ . ' called without Title object set' );
 248                         }
 249                         $this->wikipage = WikiPage::factory( $title );
 250                 }
 251
 252                 return $this->wikipage;
 253         }
 254
 255         /**
 256          * @param OutputPage $o
 257          */
 258         public function setOutput( OutputPage $o ) {
 259                 $this->output = $o;
 260         }
 261
 262         /**
 263          * Get the OutputPage object
 264          *
 265          * @return OutputPage
 266          */
 267         public function getOutput() {
 268                 if ( $this->output === null ) {
 269                         $this->output = new OutputPage( $this );
 270                 }
 271
 272                 return $this->output;
 273         }
 274
 275         /**
 276          * Set the User object
 277          *
 278          * @param User $u
 279          */
 280         public function setUser( User $u ) {
 281                 $this->user = $u;
 282         }
 283
 284         /**
 285          * Get the User object
 286          *
 287          * @return User
 288          */
 289         public function getUser() {
 290                 if ( $this->user === null ) {
 291                         $this->user = User::newFromSession( $this->getRequest() );
 292                 }
 293
 294                 return $this->user;
 295         }
 296
 297         /**
 298          * Accepts a language code and ensures it's sane. Outputs a cleaned up language
 299          * code and replaces with $wgLanguageCode if not sane.
 300          * @param string $code Language code
 301          * @return string
 302          */
 303         public static function sanitizeLangCode( $code ) {
 304                 global $wgLanguageCode;
 305
 306                 // BCP 47 - letter case MUST NOT carry meaning
 307                 $code = strtolower( $code );
 308
 309                 # Validate $code
 310                 if ( !$code || !Language::isValidCode( $code ) || $code === 'qqq' ) {
 311                         $code = $wgLanguageCode;
 312                 }
 313
 314                 return $code;
 315         }
 316
 317         /**
 318          * Set the Language object
 319          *
 320          * @param Language|string $l Language instance or language code
 321          * @throws MWException
 322          * @since 1.19
 323          */
 324         public function setLanguage( $l ) {
 325                 if ( $l instanceof Language ) {
 326                         $this->lang = $l;
 327                 } elseif ( is_string( $l ) ) {
 328                         $l = self::sanitizeLangCode( $l );
 329                         $obj = Language::factory( $l );
 330                         $this->lang = $obj;
 331                 } else {
 332                         throw new MWException( __METHOD__ . " was passed an invalid type of data." );
 333                 }
 334         }
 335
 336         /**
 337          * Get the Language object.
 338          * Initialization of user or request objects can depend on this.
 339          * @return Language
 340          * @throws Exception
 341          * @since 1.19
 342          */
 343         public function getLanguage() {
 344                 if ( isset( $this->recursion ) ) {
 345                         trigger_error( "Recursion detected in " . __METHOD__, E_USER_WARNING );
 346                         $e = new Exception;
 347                         wfDebugLog( 'recursion-guard', "Recursion detected:\n" . $e->getTraceAsString() );
 348
 349                         $code = $this->getConfig()->get( 'LanguageCode' ) ?: 'en';
 350                         $this->lang = Language::factory( $code );
 351                 } elseif ( $this->lang === null ) {
 352                         $this->recursion = true;
 353
 354                         global $wgContLang;
 355
 356                         try {
 357                                 $request = $this->getRequest();
 358                                 $user = $this->getUser();
 359
 360                                 $code = $request->getVal( 'uselang', 'user' );
 361                                 if ( $code === 'user' ) {
 362                                         $code = $user->getOption( 'language' );
 363                                 }
 364                                 $code = self::sanitizeLangCode( $code );
 365
 366                                 Hooks::run( 'UserGetLanguageObject', [ $user, &$code, $this ] );
 367
 368                                 if ( $code === $this->getConfig()->get( 'LanguageCode' ) ) {
 369                                         $this->lang = $wgContLang;
 370                                 } else {
 371                                         $obj = Language::factory( $code );
 372                                         $this->lang = $obj;
 373                                 }
 374
 375                                 unset( $this->recursion );
 376                         }
 377                         catch ( Exception $ex ) {
 378                                 unset( $this->recursion );
 379                                 throw $ex;
 380                         }
 381                 }
 382
 383                 return $this->lang;
 384         }
 385
 386         /**
 387          * Set the Skin object
 388          *
 389          * @param Skin $s
 390          */
 391         public function setSkin( Skin $s ) {
 392                 $this->skin = clone $s;
 393                 $this->skin->setContext( $this );
 394         }
 395
 396         /**
 397          * Get the Skin object
 398          *
 399          * @return Skin
 400          */
 401         public function getSkin() {
 402                 if ( $this->skin === null ) {
 403                         $skin = null;
 404                         Hooks::run( 'RequestContextCreateSkin', [ $this, &$skin ] );
 405                         $factory = SkinFactory::getDefaultInstance();
 406
 407                         // If the hook worked try to set a skin from it
 408                         if ( $skin instanceof Skin ) {
 409                                 $this->skin = $skin;
 410                         } elseif ( is_string( $skin ) ) {
 411                                 // Normalize the key, just in case the hook did something weird.
 412                                 $normalized = Skin::normalizeKey( $skin );
 413                                 $this->skin = $factory->makeSkin( $normalized );
 414                         }
 415
 416                         // If this is still null (the hook didn't run or didn't work)
 417                         // then go through the normal processing to load a skin
 418                         if ( $this->skin === null ) {
 419                                 if ( !in_array( 'skin', $this->getConfig()->get( 'HiddenPrefs' ) ) ) {
 420                                         # get the user skin
 421                                         $userSkin = $this->getUser()->getOption( 'skin' );
 422                                         $userSkin = $this->getRequest()->getVal( 'useskin', $userSkin );
 423                                 } else {
 424                                         # if we're not allowing users to override, then use the default
 425                                         $userSkin = $this->getConfig()->get( 'DefaultSkin' );
 426                                 }
 427
 428                                 // Normalize the key in case the user is passing gibberish
 429                                 // or has old preferences (T71566).
 430                                 $normalized = Skin::normalizeKey( $userSkin );
 431
 432                                 // Skin::normalizeKey will also validate it, so
 433                                 // this won't throw an exception
 434                                 $this->skin = $factory->makeSkin( $normalized );
 435                         }
 436
 437                         // After all that set a context on whatever skin got created
 438                         $this->skin->setContext( $this );
 439                 }
 440
 441                 return $this->skin;
 442         }
 443
 444         /** Helpful methods **/
 445
 446         /**
 447          * Get a Message object with context set
 448          * Parameters are the same as wfMessage()
 449          *
 450          * @param string|string[]|MessageSpecifier $key Message key, or array of keys,
 451          *   or a MessageSpecifier.
 452          * @param mixed $args,...
 453          * @return Message
 454          */
 455         public function msg( $key ) {
 456                 $args = func_get_args();
 457
 458                 return call_user_func_array( 'wfMessage', $args )->setContext( $this );
 459         }
 460
 461         /** Static methods **/
 462
 463         /**
 464          * Get the RequestContext object associated with the main request
 465          *
 466          * @return RequestContext
 467          */
 468         public static function getMain() {
 469                 if ( self::$instance === null ) {
 470                         self::$instance = new self;
 471                 }
 472
 473                 return self::$instance;
 474         }
 475
 476         /**
 477          * Get the RequestContext object associated with the main request
 478          * and gives a warning to the log, to find places, where a context maybe is missing.
 479          *
 480          * @param string $func
 481          * @return RequestContext
 482          * @since 1.24
 483          */
 484         public static function getMainAndWarn( $func = __METHOD__ ) {
 485                 wfDebug( $func . ' called without context. ' .
 486                         "Using RequestContext::getMain() for sanity\n" );
 487
 488                 return self::getMain();
 489         }
 490
 491         /**
 492          * Resets singleton returned by getMain(). Should be called only from unit tests.
 493          */
 494         public static function resetMain() {
 495                 if ( !( defined( 'MW_PHPUNIT_TEST' ) || defined( 'MW_PARSER_TEST' ) ) ) {
 496                         throw new MWException( __METHOD__ . '() should be called only from unit tests!' );
 497                 }
 498                 self::$instance = null;
 499         }
 500
 501         /**
 502          * Export the resolved user IP, HTTP headers, user ID, and session ID.
 503          * The result will be reasonably sized to allow for serialization.
 504          *
 505          * @return array
 506          * @since 1.21
 507          */
 508         public function exportSession() {
 509                 $session = MediaWiki\Session\SessionManager::getGlobalSession();
 510                 return [
 511                         'ip' => $this->getRequest()->getIP(),
 512                         'headers' => $this->getRequest()->getAllHeaders(),
 513                         'sessionId' => $session->isPersistent() ? $session->getId() : '',
 514                         'userId' => $this->getUser()->getId()
 515                 ];
 516         }
 517
 518         /**
 519          * Import an client IP address, HTTP headers, user ID, and session ID
 520          *
 521          * This sets the current session, $wgUser, and $wgRequest from $params.
 522          * Once the return value falls out of scope, the old context is restored.
 523          * This method should only be called in contexts where there is no session
 524          * ID or end user receiving the response (CLI or HTTP job runners). This
 525          * is partly enforced, and is done so to avoid leaking cookies if certain
 526          * error conditions arise.
 527          *
 528          * This is useful when background scripts inherit context when acting on
 529          * behalf of a user. In general the 'sessionId' parameter should be set
 530          * to an empty string unless session importing is *truly* needed. This
 531          * feature is somewhat deprecated.
 532          *
 533          * @note suhosin.session.encrypt may interfere with this method.
 534          *
 535          * @param array $params Result of RequestContext::exportSession()
 536          * @return ScopedCallback
 537          * @throws MWException
 538          * @since 1.21
 539          */
 540         public static function importScopedSession( array $params ) {
 541                 if ( strlen( $params['sessionId'] ) &&
 542                         MediaWiki\Session\SessionManager::getGlobalSession()->isPersistent()
 543                 ) {
 544                         // Sanity check to avoid sending random cookies for the wrong users.
 545                         // This method should only called by CLI scripts or by HTTP job runners.
 546                         throw new MWException( "Sessions can only be imported when none is active." );
 547                 } elseif ( !IP::isValid( $params['ip'] ) ) {
 548                         throw new MWException( "Invalid client IP address '{$params['ip']}'." );
 549                 }
 550
 551                 if ( $params['userId'] ) { // logged-in user
 552                         $user = User::newFromId( $params['userId'] );
 553                         $user->load();
 554                         if ( !$user->getId() ) {
 555                                 throw new MWException( "No user with ID '{$params['userId']}'." );
 556                         }
 557                 } else { // anon user
 558                         $user = User::newFromName( $params['ip'], false );
 559                 }
 560
 561                 $importSessionFunc = function ( User $user, array $params ) {
 562                         global $wgRequest, $wgUser;
 563
 564                         $context = RequestContext::getMain();
 565
 566                         // Commit and close any current session
 567                         if ( MediaWiki\Session\PHPSessionHandler::isEnabled() ) {
 568                                 session_write_close(); // persist
 569                                 session_id( '' ); // detach
 570                                 $_SESSION = []; // clear in-memory array
 571                         }
 572
 573                         // Get new session, if applicable
 574                         $session = null;
 575                         if ( strlen( $params['sessionId'] ) ) { // don't make a new random ID
 576                                 $manager = MediaWiki\Session\SessionManager::singleton();
 577                                 $session = $manager->getSessionById( $params['sessionId'], true )
 578                                         ?: $manager->getEmptySession();
 579                         }
 580
 581                         // Remove any user IP or agent information, and attach the request
 582                         // with the new session.
 583                         $context->setRequest( new FauxRequest( [], false, $session ) );
 584                         $wgRequest = $context->getRequest(); // b/c
 585
 586                         // Now that all private information is detached from the user, it should
 587                         // be safe to load the new user. If errors occur or an exception is thrown
 588                         // and caught (leaving the main context in a mixed state), there is no risk
 589                         // of the User object being attached to the wrong IP, headers, or session.
 590                         $context->setUser( $user );
 591                         $wgUser = $context->getUser(); // b/c
 592                         if ( $session && MediaWiki\Session\PHPSessionHandler::isEnabled() ) {
 593                                 session_id( $session->getId() );
 594                                 MediaWiki\quietCall( 'session_start' );
 595                         }
 596                         $request = new FauxRequest( [], false, $session );
 597                         $request->setIP( $params['ip'] );
 598                         foreach ( $params['headers'] as $name => $value ) {
 599                                 $request->setHeader( $name, $value );
 600                         }
 601                         // Set the current context to use the new WebRequest
 602                         $context->setRequest( $request );
 603                         $wgRequest = $context->getRequest(); // b/c
 604                 };
 605
 606                 // Stash the old session and load in the new one
 607                 $oUser = self::getMain()->getUser();
 608                 $oParams = self::getMain()->exportSession();
 609                 $oRequest = self::getMain()->getRequest();
 610                 $importSessionFunc( $user, $params );
 611
 612                 // Set callback to save and close the new session and reload the old one
 613                 return new ScopedCallback(
 614                         function () use ( $importSessionFunc, $oUser, $oParams, $oRequest ) {
 615                                 global $wgRequest;
 616                                 $importSessionFunc( $oUser, $oParams );
 617                                 // Restore the exact previous Request object (instead of leaving FauxRequest)
 618                                 RequestContext::getMain()->setRequest( $oRequest );
 619                                 $wgRequest = RequestContext::getMain()->getRequest(); // b/c
 620                         }
 621                 );
 622         }
 623
 624         /**
 625          * Create a new extraneous context. The context is filled with information
 626          * external to the current session.
 627          * - Title is specified by argument
 628          * - Request is a FauxRequest, or a FauxRequest can be specified by argument
 629          * - User is an anonymous user, for separation IPv4 localhost is used
 630          * - Language will be based on the anonymous user and request, may be content
 631          *   language or a uselang param in the fauxrequest data may change the lang
 632          * - Skin will be based on the anonymous user, should be the wiki's default skin
 633          *
 634          * @param Title $title Title to use for the extraneous request
 635          * @param WebRequest|array $request A WebRequest or data to use for a FauxRequest
 636          * @return RequestContext
 637          */
 638         public static function newExtraneousContext( Title $title, $request = [] ) {
 639                 $context = new self;
 640                 $context->setTitle( $title );
 641                 if ( $request instanceof WebRequest ) {
 642                         $context->setRequest( $request );
 643                 } else {
 644                         $context->setRequest( new FauxRequest( $request ) );
 645                 }
 646                 $context->user = User::newFromName( '127.0.0.1', false );
 647
 648                 return $context;
 649         }
 650 }