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
  27 /**
  28  * Group all the pieces relevant to the context of a request into one instance
  29  */
  30 class RequestContext implements IContextSource, MutableContext {
  31         /**
  32          * @var WebRequest
  33          */
  34         private $request;
  35
  36         /**
  37          * @var Title
  38          */
  39         private $title;
  40
  41         /**
  42          * @var WikiPage
  43          */
  44         private $wikipage;
  45
  46         /**
  47          * @var OutputPage
  48          */
  49         private $output;
  50
  51         /**
  52          * @var User
  53          */
  54         private $user;
  55
  56         /**
  57          * @var Language
  58          */
  59         private $lang;
  60
  61         /**
  62          * @var Skin
  63          */
  64         private $skin;
  65
  66         /**
  67          * @var \Liuggio\StatsdClient\Factory\StatsdDataFactory
  68          */
  69         private $stats;
  70
  71         /**
  72          * @var Timing
  73          */
  74         private $timing;
  75
  76         /**
  77          * @var Config
  78          */
  79         private $config;
  80
  81         /**
  82          * @var RequestContext
  83          */
  84         private static $instance = null;
  85
  86         /**
  87          * Set the Config object
  88          *
  89          * @param Config $c
  90          */
  91         public function setConfig( Config $c ) {
  92                 $this->config = $c;
  93         }
  94
  95         /**
  96          * Get the Config object
  97          *
  98          * @return Config
  99          */
 100         public function getConfig() {
 101                 if ( $this->config === null ) {
 102                         // @todo In the future, we could move this to WebStart.php so
 103                         // the Config object is ready for when initialization happens
 104                         $this->config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 105                 }
 106
 107                 return $this->config;
 108         }
 109
 110         /**
 111          * Set the WebRequest object
 112          *
 113          * @param WebRequest $r
 114          */
 115         public function setRequest( WebRequest $r ) {
 116                 $this->request = $r;
 117         }
 118
 119         /**
 120          * Get the WebRequest object
 121          *
 122          * @return WebRequest
 123          */
 124         public function getRequest() {
 125                 if ( $this->request === null ) {
 126                         global $wgRequest; # fallback to $wg till we can improve this
 127                         $this->request = $wgRequest;
 128                 }
 129
 130                 return $this->request;
 131         }
 132
 133         /**
 134          * Get the Stats object
 135          *
 136          * @return BufferingStatsdDataFactory
 137          */
 138         public function getStats() {
 139                 if ( $this->stats === null ) {
 140                         $prefix = rtrim( $this->getConfig()->get( 'StatsdMetricPrefix' ), '.' );
 141                         $this->stats = new BufferingStatsdDataFactory( $prefix );
 142                 }
 143                 return $this->stats;
 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( array(
 154                                 'logger' => LoggerFactory::getInstance( 'Timing' )
 155                         ) );
 156                 }
 157                 return $this->timing;
 158         }
 159
 160         /**
 161          * Set the Title object
 162          *
 163          * @param Title $title
 164          */
 165         public function setTitle( Title $title ) {
 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                         wfDebug( "Invalid user language code\n" );
 312                         $code = $wgLanguageCode;
 313                 }
 314
 315                 return $code;
 316         }
 317
 318         /**
 319          * Set the Language object
 320          *
 321          * @param Language|string $l Language instance or language code
 322          * @throws MWException
 323          * @since 1.19
 324          */
 325         public function setLanguage( $l ) {
 326                 if ( $l instanceof Language ) {
 327                         $this->lang = $l;
 328                 } elseif ( is_string( $l ) ) {
 329                         $l = self::sanitizeLangCode( $l );
 330                         $obj = Language::factory( $l );
 331                         $this->lang = $obj;
 332                 } else {
 333                         throw new MWException( __METHOD__ . " was passed an invalid type of data." );
 334                 }
 335         }
 336
 337         /**
 338          * Get the Language object.
 339          * Initialization of user or request objects can depend on this.
 340          * @return Language
 341          * @throws Exception
 342          * @since 1.19
 343          */
 344         public function getLanguage() {
 345                 if ( isset( $this->recursion ) ) {
 346                         trigger_error( "Recursion detected in " . __METHOD__, E_USER_WARNING );
 347                         $e = new Exception;
 348                         wfDebugLog( 'recursion-guard', "Recursion detected:\n" . $e->getTraceAsString() );
 349
 350                         $code = $this->getConfig()->get( 'LanguageCode' ) ?: 'en';
 351                         $this->lang = Language::factory( $code );
 352                 } elseif ( $this->lang === null ) {
 353                         $this->recursion = true;
 354
 355                         global $wgContLang;
 356
 357                         try {
 358                                 $request = $this->getRequest();
 359                                 $user = $this->getUser();
 360
 361                                 $code = $request->getVal( 'uselang', 'user' );
 362                                 if ( $code === 'user' ) {
 363                                         $code = $user->getOption( 'language' );
 364                                 }
 365                                 $code = self::sanitizeLangCode( $code );
 366
 367                                 Hooks::run( 'UserGetLanguageObject', array( $user, &$code, $this ) );
 368
 369                                 if ( $code === $this->getConfig()->get( 'LanguageCode' ) ) {
 370                                         $this->lang = $wgContLang;
 371                                 } else {
 372                                         $obj = Language::factory( $code );
 373                                         $this->lang = $obj;
 374                                 }
 375
 376                                 unset( $this->recursion );
 377                         }
 378                         catch ( Exception $ex ) {
 379                                 unset( $this->recursion );
 380                                 throw $ex;
 381                         }
 382                 }
 383
 384                 return $this->lang;
 385         }
 386
 387         /**
 388          * Set the Skin object
 389          *
 390          * @param Skin $s
 391          */
 392         public function setSkin( Skin $s ) {
 393                 $this->skin = clone $s;
 394                 $this->skin->setContext( $this );
 395         }
 396
 397         /**
 398          * Get the Skin object
 399          *
 400          * @return Skin
 401          */
 402         public function getSkin() {
 403                 if ( $this->skin === null ) {
 404                         $skin = null;
 405                         Hooks::run( 'RequestContextCreateSkin', array( $this, &$skin ) );
 406                         $factory = SkinFactory::getDefaultInstance();
 407
 408                         // If the hook worked try to set a skin from it
 409                         if ( $skin instanceof Skin ) {
 410                                 $this->skin = $skin;
 411                         } elseif ( is_string( $skin ) ) {
 412                                 // Normalize the key, just in case the hook did something weird.
 413                                 $normalized = Skin::normalizeKey( $skin );
 414                                 $this->skin = $factory->makeSkin( $normalized );
 415                         }
 416
 417                         // If this is still null (the hook didn't run or didn't work)
 418                         // then go through the normal processing to load a skin
 419                         if ( $this->skin === null ) {
 420                                 if ( !in_array( 'skin', $this->getConfig()->get( 'HiddenPrefs' ) ) ) {
 421                                         # get the user skin
 422                                         $userSkin = $this->getUser()->getOption( 'skin' );
 423                                         $userSkin = $this->getRequest()->getVal( 'useskin', $userSkin );
 424                                 } else {
 425                                         # if we're not allowing users to override, then use the default
 426                                         $userSkin = $this->getConfig()->get( 'DefaultSkin' );
 427                                 }
 428
 429                                 // Normalize the key in case the user is passing gibberish
 430                                 // or has old preferences (bug 69566).
 431                                 $normalized = Skin::normalizeKey( $userSkin );
 432
 433                                 // Skin::normalizeKey will also validate it, so
 434                                 // this won't throw an exception
 435                                 $this->skin = $factory->makeSkin( $normalized );
 436                         }
 437
 438                         // After all that set a context on whatever skin got created
 439                         $this->skin->setContext( $this );
 440                 }
 441
 442                 return $this->skin;
 443         }
 444
 445         /** Helpful methods **/
 446
 447         /**
 448          * Get a Message object with context set
 449          * Parameters are the same as wfMessage()
 450          *
 451          * @param mixed ...
 452          * @return Message
 453          */
 454         public function msg() {
 455                 $args = func_get_args();
 456
 457                 return call_user_func_array( 'wfMessage', $args )->setContext( $this );
 458         }
 459
 460         /** Static methods **/
 461
 462         /**
 463          * Get the RequestContext object associated with the main request
 464          *
 465          * @return RequestContext
 466          */
 467         public static function getMain() {
 468                 if ( self::$instance === null ) {
 469                         self::$instance = new self;
 470                 }
 471
 472                 return self::$instance;
 473         }
 474
 475         /**
 476          * Get the RequestContext object associated with the main request
 477          * and gives a warning to the log, to find places, where a context maybe is missing.
 478          *
 479          * @param string $func
 480          * @return RequestContext
 481          * @since 1.24
 482          */
 483         public static function getMainAndWarn( $func = __METHOD__ ) {
 484                 wfDebug( $func . ' called without context. ' .
 485                         "Using RequestContext::getMain() for sanity\n" );
 486
 487                 return self::getMain();
 488         }
 489
 490         /**
 491          * Resets singleton returned by getMain(). Should be called only from unit tests.
 492          */
 493         public static function resetMain() {
 494                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
 495                         throw new MWException( __METHOD__ . '() should be called only from unit tests!' );
 496                 }
 497                 self::$instance = null;
 498         }
 499
 500         /**
 501          * Export the resolved user IP, HTTP headers, user ID, and session ID.
 502          * The result will be reasonably sized to allow for serialization.
 503          *
 504          * @return array
 505          * @since 1.21
 506          */
 507         public function exportSession() {
 508                 return array(
 509                         'ip' => $this->getRequest()->getIP(),
 510                         'headers' => $this->getRequest()->getAllHeaders(),
 511                         'sessionId' => session_id(),
 512                         'userId' => $this->getUser()->getId()
 513                 );
 514         }
 515
 516         /**
 517          * Import an client IP address, HTTP headers, user ID, and session ID
 518          *
 519          * This sets the current session, $wgUser, and $wgRequest from $params.
 520          * Once the return value falls out of scope, the old context is restored.
 521          * This method should only be called in contexts where there is no session
 522          * ID or end user receiving the response (CLI or HTTP job runners). This
 523          * is partly enforced, and is done so to avoid leaking cookies if certain
 524          * error conditions arise.
 525          *
 526          * This is useful when background scripts inherit context when acting on
 527          * behalf of a user. In general the 'sessionId' parameter should be set
 528          * to an empty string unless session importing is *truly* needed. This
 529          * feature is somewhat deprecated.
 530          *
 531          * @note suhosin.session.encrypt may interfere with this method.
 532          *
 533          * @param array $params Result of RequestContext::exportSession()
 534          * @return ScopedCallback
 535          * @throws MWException
 536          * @since 1.21
 537          */
 538         public static function importScopedSession( array $params ) {
 539                 if ( session_id() != '' && strlen( $params['sessionId'] ) ) {
 540                         // Sanity check to avoid sending random cookies for the wrong users.
 541                         // This method should only called by CLI scripts or by HTTP job runners.
 542                         throw new MWException( "Sessions can only be imported when none is active." );
 543                 } elseif ( !IP::isValid( $params['ip'] ) ) {
 544                         throw new MWException( "Invalid client IP address '{$params['ip']}'." );
 545                 }
 546
 547                 if ( $params['userId'] ) { // logged-in user
 548                         $user = User::newFromId( $params['userId'] );
 549                         $user->load();
 550                         if ( !$user->getId() ) {
 551                                 throw new MWException( "No user with ID '{$params['userId']}'." );
 552                         }
 553                 } else { // anon user
 554                         $user = User::newFromName( $params['ip'], false );
 555                 }
 556
 557                 $importSessionFunc = function ( User $user, array $params ) {
 558                         global $wgRequest, $wgUser;
 559
 560                         $context = RequestContext::getMain();
 561                         // Commit and close any current session
 562                         session_write_close(); // persist
 563                         session_id( '' ); // detach
 564                         $_SESSION = array(); // clear in-memory array
 565                         // Remove any user IP or agent information
 566                         $context->setRequest( new FauxRequest() );
 567                         $wgRequest = $context->getRequest(); // b/c
 568                         // Now that all private information is detached from the user, it should
 569                         // be safe to load the new user. If errors occur or an exception is thrown
 570                         // and caught (leaving the main context in a mixed state), there is no risk
 571                         // of the User object being attached to the wrong IP, headers, or session.
 572                         $context->setUser( $user );
 573                         $wgUser = $context->getUser(); // b/c
 574                         if ( strlen( $params['sessionId'] ) ) { // don't make a new random ID
 575                                 wfSetupSession( $params['sessionId'] ); // sets $_SESSION
 576                         }
 577                         $request = new FauxRequest( array(), false, $_SESSION );
 578                         $request->setIP( $params['ip'] );
 579                         foreach ( $params['headers'] as $name => $value ) {
 580                                 $request->setHeader( $name, $value );
 581                         }
 582                         // Set the current context to use the new WebRequest
 583                         $context->setRequest( $request );
 584                         $wgRequest = $context->getRequest(); // b/c
 585                 };
 586
 587                 // Stash the old session and load in the new one
 588                 $oUser = self::getMain()->getUser();
 589                 $oParams = self::getMain()->exportSession();
 590                 $oRequest = self::getMain()->getRequest();
 591                 $importSessionFunc( $user, $params );
 592
 593                 // Set callback to save and close the new session and reload the old one
 594                 return new ScopedCallback(
 595                         function () use ( $importSessionFunc, $oUser, $oParams, $oRequest ) {
 596                                 global $wgRequest;
 597                                 $importSessionFunc( $oUser, $oParams );
 598                                 // Restore the exact previous Request object (instead of leaving FauxRequest)
 599                                 RequestContext::getMain()->setRequest( $oRequest );
 600                                 $wgRequest = RequestContext::getMain()->getRequest(); // b/c
 601                         }
 602                 );
 603         }
 604
 605         /**
 606          * Create a new extraneous context. The context is filled with information
 607          * external to the current session.
 608          * - Title is specified by argument
 609          * - Request is a FauxRequest, or a FauxRequest can be specified by argument
 610          * - User is an anonymous user, for separation IPv4 localhost is used
 611          * - Language will be based on the anonymous user and request, may be content
 612          *   language or a uselang param in the fauxrequest data may change the lang
 613          * - Skin will be based on the anonymous user, should be the wiki's default skin
 614          *
 615          * @param Title $title Title to use for the extraneous request
 616          * @param WebRequest|array $request A WebRequest or data to use for a FauxRequest
 617          * @return RequestContext
 618          */
 619         public static function newExtraneousContext( Title $title, $request = array() ) {
 620                 $context = new self;
 621                 $context->setTitle( $title );
 622                 if ( $request instanceof WebRequest ) {
 623                         $context->setRequest( $request );
 624                 } else {
 625                         $context->setRequest( new FauxRequest( $request ) );
 626                 }
 627                 $context->user = User::newFromName( '127.0.0.1', false );
 628
 629                 return $context;
 630         }
 631 }