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                         $config = $this->getConfig();
 141                         $prefix = $config->get( 'StatsdMetricPrefix' )
 142                                 ? rtrim( $config->get( 'StatsdMetricPrefix' ), '.' )
 143                                 : 'MediaWiki';
 144                         $this->stats = new BufferingStatsdDataFactory( $prefix );
 145                 }
 146                 return $this->stats;
 147         }
 148
 149         /**
 150          * Get the timing object
 151          *
 152          * @return Timing
 153          */
 154         public function getTiming() {
 155                 if ( $this->timing === null ) {
 156                         $this->timing = new Timing( array(
 157                                 'logger' => LoggerFactory::getInstance( 'Timing' )
 158                         ) );
 159                 }
 160                 return $this->timing;
 161         }
 162
 163         /**
 164          * Set the Title object
 165          *
 166          * @param Title $title
 167          */
 168         public function setTitle( Title $title ) {
 169                 $this->title = $title;
 170                 // Erase the WikiPage so a new one with the new title gets created.
 171                 $this->wikipage = null;
 172         }
 173
 174         /**
 175          * Get the Title object
 176          *
 177          * @return Title|null
 178          */
 179         public function getTitle() {
 180                 if ( $this->title === null ) {
 181                         global $wgTitle; # fallback to $wg till we can improve this
 182                         $this->title = $wgTitle;
 183                         wfDebugLog(
 184                                 'GlobalTitleFail',
 185                                 __METHOD__ . ' called by ' . wfGetAllCallers( 5 ) . ' with no title set.'
 186                         );
 187                 }
 188
 189                 return $this->title;
 190         }
 191
 192         /**
 193          * Check, if a Title object is set
 194          *
 195          * @since 1.25
 196          * @return bool
 197          */
 198         public function hasTitle() {
 199                 return $this->title !== null;
 200         }
 201
 202         /**
 203          * Check whether a WikiPage object can be get with getWikiPage().
 204          * Callers should expect that an exception is thrown from getWikiPage()
 205          * if this method returns false.
 206          *
 207          * @since 1.19
 208          * @return bool
 209          */
 210         public function canUseWikiPage() {
 211                 if ( $this->wikipage ) {
 212                         // If there's a WikiPage object set, we can for sure get it
 213                         return true;
 214                 }
 215                 // Only pages with legitimate titles can have WikiPages.
 216                 // That usually means pages in non-virtual namespaces.
 217                 $title = $this->getTitle();
 218                 return $title ? $title->canExist() : false;
 219         }
 220
 221         /**
 222          * Set the WikiPage object
 223          *
 224          * @since 1.19
 225          * @param WikiPage $p
 226          */
 227         public function setWikiPage( WikiPage $p ) {
 228                 $pageTitle = $p->getTitle();
 229                 if ( !$this->hasTitle() || !$pageTitle->equals( $this->getTitle() ) ) {
 230                         $this->setTitle( $pageTitle );
 231                 }
 232                 // Defer this to the end since setTitle sets it to null.
 233                 $this->wikipage = $p;
 234         }
 235
 236         /**
 237          * Get the WikiPage object.
 238          * May throw an exception if there's no Title object set or the Title object
 239          * belongs to a special namespace that doesn't have WikiPage, so use first
 240          * canUseWikiPage() to check whether this method can be called safely.
 241          *
 242          * @since 1.19
 243          * @throws MWException
 244          * @return WikiPage
 245          */
 246         public function getWikiPage() {
 247                 if ( $this->wikipage === null ) {
 248                         $title = $this->getTitle();
 249                         if ( $title === null ) {
 250                                 throw new MWException( __METHOD__ . ' called without Title object set' );
 251                         }
 252                         $this->wikipage = WikiPage::factory( $title );
 253                 }
 254
 255                 return $this->wikipage;
 256         }
 257
 258         /**
 259          * @param OutputPage $o
 260          */
 261         public function setOutput( OutputPage $o ) {
 262                 $this->output = $o;
 263         }
 264
 265         /**
 266          * Get the OutputPage object
 267          *
 268          * @return OutputPage
 269          */
 270         public function getOutput() {
 271                 if ( $this->output === null ) {
 272                         $this->output = new OutputPage( $this );
 273                 }
 274
 275                 return $this->output;
 276         }
 277
 278         /**
 279          * Set the User object
 280          *
 281          * @param User $u
 282          */
 283         public function setUser( User $u ) {
 284                 $this->user = $u;
 285         }
 286
 287         /**
 288          * Get the User object
 289          *
 290          * @return User
 291          */
 292         public function getUser() {
 293                 if ( $this->user === null ) {
 294                         $this->user = User::newFromSession( $this->getRequest() );
 295                 }
 296
 297                 return $this->user;
 298         }
 299
 300         /**
 301          * Accepts a language code and ensures it's sane. Outputs a cleaned up language
 302          * code and replaces with $wgLanguageCode if not sane.
 303          * @param string $code Language code
 304          * @return string
 305          */
 306         public static function sanitizeLangCode( $code ) {
 307                 global $wgLanguageCode;
 308
 309                 // BCP 47 - letter case MUST NOT carry meaning
 310                 $code = strtolower( $code );
 311
 312                 # Validate $code
 313                 if ( !$code || !Language::isValidCode( $code ) || $code === 'qqq' ) {
 314                         wfDebug( "Invalid user language code\n" );
 315                         $code = $wgLanguageCode;
 316                 }
 317
 318                 return $code;
 319         }
 320
 321         /**
 322          * Set the Language object
 323          *
 324          * @param Language|string $l Language instance or language code
 325          * @throws MWException
 326          * @since 1.19
 327          */
 328         public function setLanguage( $l ) {
 329                 if ( $l instanceof Language ) {
 330                         $this->lang = $l;
 331                 } elseif ( is_string( $l ) ) {
 332                         $l = self::sanitizeLangCode( $l );
 333                         $obj = Language::factory( $l );
 334                         $this->lang = $obj;
 335                 } else {
 336                         throw new MWException( __METHOD__ . " was passed an invalid type of data." );
 337                 }
 338         }
 339
 340         /**
 341          * Get the Language object.
 342          * Initialization of user or request objects can depend on this.
 343          * @return Language
 344          * @throws Exception
 345          * @since 1.19
 346          */
 347         public function getLanguage() {
 348                 if ( isset( $this->recursion ) ) {
 349                         trigger_error( "Recursion detected in " . __METHOD__, E_USER_WARNING );
 350                         $e = new Exception;
 351                         wfDebugLog( 'recursion-guard', "Recursion detected:\n" . $e->getTraceAsString() );
 352
 353                         $code = $this->getConfig()->get( 'LanguageCode' ) ?: 'en';
 354                         $this->lang = Language::factory( $code );
 355                 } elseif ( $this->lang === null ) {
 356                         $this->recursion = true;
 357
 358                         global $wgContLang;
 359
 360                         try {
 361                                 $request = $this->getRequest();
 362                                 $user = $this->getUser();
 363
 364                                 $code = $request->getVal( 'uselang', 'user' );
 365                                 if ( $code === 'user' ) {
 366                                         $code = $user->getOption( 'language' );
 367                                 }
 368                                 $code = self::sanitizeLangCode( $code );
 369
 370                                 Hooks::run( 'UserGetLanguageObject', array( $user, &$code, $this ) );
 371
 372                                 if ( $code === $this->getConfig()->get( 'LanguageCode' ) ) {
 373                                         $this->lang = $wgContLang;
 374                                 } else {
 375                                         $obj = Language::factory( $code );
 376                                         $this->lang = $obj;
 377                                 }
 378
 379                                 unset( $this->recursion );
 380                         }
 381                         catch ( Exception $ex ) {
 382                                 unset( $this->recursion );
 383                                 throw $ex;
 384                         }
 385                 }
 386
 387                 return $this->lang;
 388         }
 389
 390         /**
 391          * Set the Skin object
 392          *
 393          * @param Skin $s
 394          */
 395         public function setSkin( Skin $s ) {
 396                 $this->skin = clone $s;
 397                 $this->skin->setContext( $this );
 398         }
 399
 400         /**
 401          * Get the Skin object
 402          *
 403          * @return Skin
 404          */
 405         public function getSkin() {
 406                 if ( $this->skin === null ) {
 407                         $skin = null;
 408                         Hooks::run( 'RequestContextCreateSkin', array( $this, &$skin ) );
 409                         $factory = SkinFactory::getDefaultInstance();
 410
 411                         // If the hook worked try to set a skin from it
 412                         if ( $skin instanceof Skin ) {
 413                                 $this->skin = $skin;
 414                         } elseif ( is_string( $skin ) ) {
 415                                 // Normalize the key, just in case the hook did something weird.
 416                                 $normalized = Skin::normalizeKey( $skin );
 417                                 $this->skin = $factory->makeSkin( $normalized );
 418                         }
 419
 420                         // If this is still null (the hook didn't run or didn't work)
 421                         // then go through the normal processing to load a skin
 422                         if ( $this->skin === null ) {
 423                                 if ( !in_array( 'skin', $this->getConfig()->get( 'HiddenPrefs' ) ) ) {
 424                                         # get the user skin
 425                                         $userSkin = $this->getUser()->getOption( 'skin' );
 426                                         $userSkin = $this->getRequest()->getVal( 'useskin', $userSkin );
 427                                 } else {
 428                                         # if we're not allowing users to override, then use the default
 429                                         $userSkin = $this->getConfig()->get( 'DefaultSkin' );
 430                                 }
 431
 432                                 // Normalize the key in case the user is passing gibberish
 433                                 // or has old preferences (bug 69566).
 434                                 $normalized = Skin::normalizeKey( $userSkin );
 435
 436                                 // Skin::normalizeKey will also validate it, so
 437                                 // this won't throw an exception
 438                                 $this->skin = $factory->makeSkin( $normalized );
 439                         }
 440
 441                         // After all that set a context on whatever skin got created
 442                         $this->skin->setContext( $this );
 443                 }
 444
 445                 return $this->skin;
 446         }
 447
 448         /** Helpful methods **/
 449
 450         /**
 451          * Get a Message object with context set
 452          * Parameters are the same as wfMessage()
 453          *
 454          * @param mixed ...
 455          * @return Message
 456          */
 457         public function msg() {
 458                 $args = func_get_args();
 459
 460                 return call_user_func_array( 'wfMessage', $args )->setContext( $this );
 461         }
 462
 463         /** Static methods **/
 464
 465         /**
 466          * Get the RequestContext object associated with the main request
 467          *
 468          * @return RequestContext
 469          */
 470         public static function getMain() {
 471                 if ( self::$instance === null ) {
 472                         self::$instance = new self;
 473                 }
 474
 475                 return self::$instance;
 476         }
 477
 478         /**
 479          * Get the RequestContext object associated with the main request
 480          * and gives a warning to the log, to find places, where a context maybe is missing.
 481          *
 482          * @param string $func
 483          * @return RequestContext
 484          * @since 1.24
 485          */
 486         public static function getMainAndWarn( $func = __METHOD__ ) {
 487                 wfDebug( $func . ' called without context. ' .
 488                         "Using RequestContext::getMain() for sanity\n" );
 489
 490                 return self::getMain();
 491         }
 492
 493         /**
 494          * Resets singleton returned by getMain(). Should be called only from unit tests.
 495          */
 496         public static function resetMain() {
 497                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
 498                         throw new MWException( __METHOD__ . '() should be called only from unit tests!' );
 499                 }
 500                 self::$instance = null;
 501         }
 502
 503         /**
 504          * Export the resolved user IP, HTTP headers, user ID, and session ID.
 505          * The result will be reasonably sized to allow for serialization.
 506          *
 507          * @return array
 508          * @since 1.21
 509          */
 510         public function exportSession() {
 511                 return array(
 512                         'ip' => $this->getRequest()->getIP(),
 513                         'headers' => $this->getRequest()->getAllHeaders(),
 514                         'sessionId' => session_id(),
 515                         'userId' => $this->getUser()->getId()
 516                 );
 517         }
 518
 519         /**
 520          * Import an client IP address, HTTP headers, user ID, and session ID
 521          *
 522          * This sets the current session, $wgUser, and $wgRequest from $params.
 523          * Once the return value falls out of scope, the old context is restored.
 524          * This method should only be called in contexts where there is no session
 525          * ID or end user receiving the response (CLI or HTTP job runners). This
 526          * is partly enforced, and is done so to avoid leaking cookies if certain
 527          * error conditions arise.
 528          *
 529          * This is useful when background scripts inherit context when acting on
 530          * behalf of a user. In general the 'sessionId' parameter should be set
 531          * to an empty string unless session importing is *truly* needed. This
 532          * feature is somewhat deprecated.
 533          *
 534          * @note suhosin.session.encrypt may interfere with this method.
 535          *
 536          * @param array $params Result of RequestContext::exportSession()
 537          * @return ScopedCallback
 538          * @throws MWException
 539          * @since 1.21
 540          */
 541         public static function importScopedSession( array $params ) {
 542                 if ( session_id() != '' && strlen( $params['sessionId'] ) ) {
 543                         // Sanity check to avoid sending random cookies for the wrong users.
 544                         // This method should only called by CLI scripts or by HTTP job runners.
 545                         throw new MWException( "Sessions can only be imported when none is active." );
 546                 } elseif ( !IP::isValid( $params['ip'] ) ) {
 547                         throw new MWException( "Invalid client IP address '{$params['ip']}'." );
 548                 }
 549
 550                 if ( $params['userId'] ) { // logged-in user
 551                         $user = User::newFromId( $params['userId'] );
 552                         $user->load();
 553                         if ( !$user->getId() ) {
 554                                 throw new MWException( "No user with ID '{$params['userId']}'." );
 555                         }
 556                 } else { // anon user
 557                         $user = User::newFromName( $params['ip'], false );
 558                 }
 559
 560                 $importSessionFunc = function ( User $user, array $params ) {
 561                         global $wgRequest, $wgUser;
 562
 563                         $context = RequestContext::getMain();
 564                         // Commit and close any current session
 565                         session_write_close(); // persist
 566                         session_id( '' ); // detach
 567                         $_SESSION = array(); // clear in-memory array
 568                         // Remove any user IP or agent information
 569                         $context->setRequest( new FauxRequest() );
 570                         $wgRequest = $context->getRequest(); // b/c
 571                         // Now that all private information is detached from the user, it should
 572                         // be safe to load the new user. If errors occur or an exception is thrown
 573                         // and caught (leaving the main context in a mixed state), there is no risk
 574                         // of the User object being attached to the wrong IP, headers, or session.
 575                         $context->setUser( $user );
 576                         $wgUser = $context->getUser(); // b/c
 577                         if ( strlen( $params['sessionId'] ) ) { // don't make a new random ID
 578                                 wfSetupSession( $params['sessionId'] ); // sets $_SESSION
 579                         }
 580                         $request = new FauxRequest( array(), false, $_SESSION );
 581                         $request->setIP( $params['ip'] );
 582                         foreach ( $params['headers'] as $name => $value ) {
 583                                 $request->setHeader( $name, $value );
 584                         }
 585                         // Set the current context to use the new WebRequest
 586                         $context->setRequest( $request );
 587                         $wgRequest = $context->getRequest(); // b/c
 588                 };
 589
 590                 // Stash the old session and load in the new one
 591                 $oUser = self::getMain()->getUser();
 592                 $oParams = self::getMain()->exportSession();
 593                 $oRequest = self::getMain()->getRequest();
 594                 $importSessionFunc( $user, $params );
 595
 596                 // Set callback to save and close the new session and reload the old one
 597                 return new ScopedCallback(
 598                         function () use ( $importSessionFunc, $oUser, $oParams, $oRequest ) {
 599                                 global $wgRequest;
 600                                 $importSessionFunc( $oUser, $oParams );
 601                                 // Restore the exact previous Request object (instead of leaving FauxRequest)
 602                                 RequestContext::getMain()->setRequest( $oRequest );
 603                                 $wgRequest = RequestContext::getMain()->getRequest(); // b/c
 604                         }
 605                 );
 606         }
 607
 608         /**
 609          * Create a new extraneous context. The context is filled with information
 610          * external to the current session.
 611          * - Title is specified by argument
 612          * - Request is a FauxRequest, or a FauxRequest can be specified by argument
 613          * - User is an anonymous user, for separation IPv4 localhost is used
 614          * - Language will be based on the anonymous user and request, may be content
 615          *   language or a uselang param in the fauxrequest data may change the lang
 616          * - Skin will be based on the anonymous user, should be the wiki's default skin
 617          *
 618          * @param Title $title Title to use for the extraneous request
 619          * @param WebRequest|array $request A WebRequest or data to use for a FauxRequest
 620          * @return RequestContext
 621          */
 622         public static function newExtraneousContext( Title $title, $request = array() ) {
 623                 $context = new self;
 624                 $context->setTitle( $title );
 625                 if ( $request instanceof WebRequest ) {
 626                         $context->setRequest( $request );
 627                 } else {
 628                         $context->setRequest( new FauxRequest( $request ) );
 629                 }
 630                 $context->user = User::newFromName( '127.0.0.1', false );
 631
 632                 return $context;
 633         }
 634 }