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 /**
  26  * Group all the pieces relevant to the context of a request into one instance
  27  */
  28 class RequestContext implements IContextSource, MutableContext {
  29         /**
  30          * @var WebRequest
  31          */
  32         private $request;
  33
  34         /**
  35          * @var Title
  36          */
  37         private $title;
  38
  39         /**
  40          * @var WikiPage
  41          */
  42         private $wikipage;
  43
  44         /**
  45          * @var OutputPage
  46          */
  47         private $output;
  48
  49         /**
  50          * @var User
  51          */
  52         private $user;
  53
  54         /**
  55          * @var Language
  56          */
  57         private $lang;
  58
  59         /**
  60          * @var Skin
  61          */
  62         private $skin;
  63
  64         /**
  65          * @var \Liuggio\StatsdClient\Factory\StatsdDataFactory
  66          */
  67         private $stats;
  68
  69         /**
  70          * @var Config
  71          */
  72         private $config;
  73
  74         /**
  75          * @var RequestContext
  76          */
  77         private static $instance = null;
  78
  79         /**
  80          * Set the Config object
  81          *
  82          * @param Config $c
  83          */
  84         public function setConfig( Config $c ) {
  85                 $this->config = $c;
  86         }
  87
  88         /**
  89          * Get the Config object
  90          *
  91          * @return Config
  92          */
  93         public function getConfig() {
  94                 if ( $this->config === null ) {
  95                         // @todo In the future, we could move this to WebStart.php so
  96                         // the Config object is ready for when initialization happens
  97                         $this->config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
  98                 }
  99
 100                 return $this->config;
 101         }
 102
 103         /**
 104          * Set the WebRequest object
 105          *
 106          * @param WebRequest $r
 107          */
 108         public function setRequest( WebRequest $r ) {
 109                 $this->request = $r;
 110         }
 111
 112         /**
 113          * Get the WebRequest object
 114          *
 115          * @return WebRequest
 116          */
 117         public function getRequest() {
 118                 if ( $this->request === null ) {
 119                         global $wgRequest; # fallback to $wg till we can improve this
 120                         $this->request = $wgRequest;
 121                 }
 122
 123                 return $this->request;
 124         }
 125
 126         /**
 127          * Get the Stats object
 128          *
 129          * @return BufferingStatsdDataFactory
 130          */
 131         public function getStats() {
 132                 if ( $this->stats === null ) {
 133                         $config = $this->getConfig();
 134                         $prefix = $config->get( 'StatsdMetricPrefix' )
 135                                 ? rtrim( $config->get( 'StatsdMetricPrefix' ), '.' )
 136                                 : 'MediaWiki';
 137                         $this->stats = new BufferingStatsdDataFactory( $prefix );
 138                 }
 139                 return $this->stats;
 140         }
 141
 142         /**
 143          * Set the Title object
 144          *
 145          * @param Title $title
 146          */
 147         public function setTitle( Title $title ) {
 148                 $this->title = $title;
 149                 // Erase the WikiPage so a new one with the new title gets created.
 150                 $this->wikipage = null;
 151         }
 152
 153         /**
 154          * Get the Title object
 155          *
 156          * @return Title|null
 157          */
 158         public function getTitle() {
 159                 if ( $this->title === null ) {
 160                         global $wgTitle; # fallback to $wg till we can improve this
 161                         $this->title = $wgTitle;
 162                         wfDebugLog( 'GlobalTitleFail', __METHOD__ . ' called by ' . wfGetAllCallers( 5 ) . ' with no title set.' );
 163                 }
 164
 165                 return $this->title;
 166         }
 167
 168         /**
 169          * Check, if a Title object is set
 170          *
 171          * @since 1.25
 172          * @return bool
 173          */
 174         public function hasTitle() {
 175                 return $this->title !== null;
 176         }
 177
 178         /**
 179          * Check whether a WikiPage object can be get with getWikiPage().
 180          * Callers should expect that an exception is thrown from getWikiPage()
 181          * if this method returns false.
 182          *
 183          * @since 1.19
 184          * @return bool
 185          */
 186         public function canUseWikiPage() {
 187                 if ( $this->wikipage ) {
 188                         // If there's a WikiPage object set, we can for sure get it
 189                         return true;
 190                 }
 191                 // Only pages with legitimate titles can have WikiPages.
 192                 // That usually means pages in non-virtual namespaces.
 193                 $title = $this->getTitle();
 194                 return $title ? $title->canExist() : false;
 195         }
 196
 197         /**
 198          * Set the WikiPage object
 199          *
 200          * @since 1.19
 201          * @param WikiPage $p
 202          */
 203         public function setWikiPage( WikiPage $p ) {
 204                 $pageTitle = $p->getTitle();
 205                 if ( !$this->hasTitle() || !$pageTitle->equals( $this->getTitle() ) ) {
 206                         $this->setTitle( $pageTitle );
 207                 }
 208                 // Defer this to the end since setTitle sets it to null.
 209                 $this->wikipage = $p;
 210         }
 211
 212         /**
 213          * Get the WikiPage object.
 214          * May throw an exception if there's no Title object set or the Title object
 215          * belongs to a special namespace that doesn't have WikiPage, so use first
 216          * canUseWikiPage() to check whether this method can be called safely.
 217          *
 218          * @since 1.19
 219          * @throws MWException
 220          * @return WikiPage
 221          */
 222         public function getWikiPage() {
 223                 if ( $this->wikipage === null ) {
 224                         $title = $this->getTitle();
 225                         if ( $title === null ) {
 226                                 throw new MWException( __METHOD__ . ' called without Title object set' );
 227                         }
 228                         $this->wikipage = WikiPage::factory( $title );
 229                 }
 230
 231                 return $this->wikipage;
 232         }
 233
 234         /**
 235          * @param OutputPage $o
 236          */
 237         public function setOutput( OutputPage $o ) {
 238                 $this->output = $o;
 239         }
 240
 241         /**
 242          * Get the OutputPage object
 243          *
 244          * @return OutputPage
 245          */
 246         public function getOutput() {
 247                 if ( $this->output === null ) {
 248                         $this->output = new OutputPage( $this );
 249                 }
 250
 251                 return $this->output;
 252         }
 253
 254         /**
 255          * Set the User object
 256          *
 257          * @param User $u
 258          */
 259         public function setUser( User $u ) {
 260                 $this->user = $u;
 261         }
 262
 263         /**
 264          * Get the User object
 265          *
 266          * @return User
 267          */
 268         public function getUser() {
 269                 if ( $this->user === null ) {
 270                         $this->user = User::newFromSession( $this->getRequest() );
 271                 }
 272
 273                 return $this->user;
 274         }
 275
 276         /**
 277          * Accepts a language code and ensures it's sane. Outputs a cleaned up language
 278          * code and replaces with $wgLanguageCode if not sane.
 279          * @param string $code Language code
 280          * @return string
 281          */
 282         public static function sanitizeLangCode( $code ) {
 283                 global $wgLanguageCode;
 284
 285                 // BCP 47 - letter case MUST NOT carry meaning
 286                 $code = strtolower( $code );
 287
 288                 # Validate $code
 289                 if ( !$code || !Language::isValidCode( $code ) || $code === 'qqq' ) {
 290                         wfDebug( "Invalid user language code\n" );
 291                         $code = $wgLanguageCode;
 292                 }
 293
 294                 return $code;
 295         }
 296
 297         /**
 298          * Set the Language object
 299          *
 300          * @param Language|string $l Language instance or language code
 301          * @throws MWException
 302          * @since 1.19
 303          */
 304         public function setLanguage( $l ) {
 305                 if ( $l instanceof Language ) {
 306                         $this->lang = $l;
 307                 } elseif ( is_string( $l ) ) {
 308                         $l = self::sanitizeLangCode( $l );
 309                         $obj = Language::factory( $l );
 310                         $this->lang = $obj;
 311                 } else {
 312                         throw new MWException( __METHOD__ . " was passed an invalid type of data." );
 313                 }
 314         }
 315
 316         /**
 317          * Get the Language object.
 318          * Initialization of user or request objects can depend on this.
 319          * @return Language
 320          * @throws Exception
 321          * @since 1.19
 322          */
 323         public function getLanguage() {
 324                 if ( isset( $this->recursion ) ) {
 325                         trigger_error( "Recursion detected in " . __METHOD__, E_USER_WARNING );
 326                         $e = new Exception;
 327                         wfDebugLog( 'recursion-guard', "Recursion detected:\n" . $e->getTraceAsString() );
 328
 329                         $code = $this->getConfig()->get( 'LanguageCode' ) ?: 'en';
 330                         $this->lang = Language::factory( $code );
 331                 } elseif ( $this->lang === null ) {
 332                         $this->recursion = true;
 333
 334                         global $wgContLang;
 335
 336                         try {
 337                                 $request = $this->getRequest();
 338                                 $user = $this->getUser();
 339
 340                                 $code = $request->getVal( 'uselang', 'user' );
 341                                 if ( $code === 'user' ) {
 342                                         $code = $user->getOption( 'language' );
 343                                 }
 344                                 $code = self::sanitizeLangCode( $code );
 345
 346                                 Hooks::run( 'UserGetLanguageObject', array( $user, &$code, $this ) );
 347
 348                                 if ( $code === $this->getConfig()->get( 'LanguageCode' ) ) {
 349                                         $this->lang = $wgContLang;
 350                                 } else {
 351                                         $obj = Language::factory( $code );
 352                                         $this->lang = $obj;
 353                                 }
 354
 355                                 unset( $this->recursion );
 356                         }
 357                         catch ( Exception $ex ) {
 358                                 unset( $this->recursion );
 359                                 throw $ex;
 360                         }
 361                 }
 362
 363                 return $this->lang;
 364         }
 365
 366         /**
 367          * Set the Skin object
 368          *
 369          * @param Skin $s
 370          */
 371         public function setSkin( Skin $s ) {
 372                 $this->skin = clone $s;
 373                 $this->skin->setContext( $this );
 374         }
 375
 376         /**
 377          * Get the Skin object
 378          *
 379          * @return Skin
 380          */
 381         public function getSkin() {
 382                 if ( $this->skin === null ) {
 383                         $skin = null;
 384                         Hooks::run( 'RequestContextCreateSkin', array( $this, &$skin ) );
 385                         $factory = SkinFactory::getDefaultInstance();
 386
 387                         // If the hook worked try to set a skin from it
 388                         if ( $skin instanceof Skin ) {
 389                                 $this->skin = $skin;
 390                         } elseif ( is_string( $skin ) ) {
 391                                 // Normalize the key, just in case the hook did something weird.
 392                                 $normalized = Skin::normalizeKey( $skin );
 393                                 $this->skin = $factory->makeSkin( $normalized );
 394                         }
 395
 396                         // If this is still null (the hook didn't run or didn't work)
 397                         // then go through the normal processing to load a skin
 398                         if ( $this->skin === null ) {
 399                                 if ( !in_array( 'skin', $this->getConfig()->get( 'HiddenPrefs' ) ) ) {
 400                                         # get the user skin
 401                                         $userSkin = $this->getUser()->getOption( 'skin' );
 402                                         $userSkin = $this->getRequest()->getVal( 'useskin', $userSkin );
 403                                 } else {
 404                                         # if we're not allowing users to override, then use the default
 405                                         $userSkin = $this->getConfig()->get( 'DefaultSkin' );
 406                                 }
 407
 408                                 // Normalize the key in case the user is passing gibberish
 409                                 // or has old preferences (bug 69566).
 410                                 $normalized = Skin::normalizeKey( $userSkin );
 411
 412                                 // Skin::normalizeKey will also validate it, so
 413                                 // this won't throw an exception
 414                                 $this->skin = $factory->makeSkin( $normalized );
 415                         }
 416
 417                         // After all that set a context on whatever skin got created
 418                         $this->skin->setContext( $this );
 419                 }
 420
 421                 return $this->skin;
 422         }
 423
 424         /** Helpful methods **/
 425
 426         /**
 427          * Get a Message object with context set
 428          * Parameters are the same as wfMessage()
 429          *
 430          * @param mixed ...
 431          * @return Message
 432          */
 433         public function msg() {
 434                 $args = func_get_args();
 435
 436                 return call_user_func_array( 'wfMessage', $args )->setContext( $this );
 437         }
 438
 439         /** Static methods **/
 440
 441         /**
 442          * Get the RequestContext object associated with the main request
 443          *
 444          * @return RequestContext
 445          */
 446         public static function getMain() {
 447                 if ( self::$instance === null ) {
 448                         self::$instance = new self;
 449                 }
 450
 451                 return self::$instance;
 452         }
 453
 454         /**
 455          * Get the RequestContext object associated with the main request
 456          * and gives a warning to the log, to find places, where a context maybe is missing.
 457          *
 458          * @param string $func
 459          * @return RequestContext
 460          * @since 1.24
 461          */
 462         public static function getMainAndWarn( $func = __METHOD__ ) {
 463                 wfDebug( $func . ' called without context. ' .
 464                         "Using RequestContext::getMain() for sanity\n" );
 465
 466                 return self::getMain();
 467         }
 468
 469         /**
 470          * Resets singleton returned by getMain(). Should be called only from unit tests.
 471          */
 472         public static function resetMain() {
 473                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
 474                         throw new MWException( __METHOD__ . '() should be called only from unit tests!' );
 475                 }
 476                 self::$instance = null;
 477         }
 478
 479         /**
 480          * Export the resolved user IP, HTTP headers, user ID, and session ID.
 481          * The result will be reasonably sized to allow for serialization.
 482          *
 483          * @return array
 484          * @since 1.21
 485          */
 486         public function exportSession() {
 487                 return array(
 488                         'ip' => $this->getRequest()->getIP(),
 489                         'headers' => $this->getRequest()->getAllHeaders(),
 490                         'sessionId' => session_id(),
 491                         'userId' => $this->getUser()->getId()
 492                 );
 493         }
 494
 495         /**
 496          * Import an client IP address, HTTP headers, user ID, and session ID
 497          *
 498          * This sets the current session, $wgUser, and $wgRequest from $params.
 499          * Once the return value falls out of scope, the old context is restored.
 500          * This method should only be called in contexts where there is no session
 501          * ID or end user receiving the response (CLI or HTTP job runners). This
 502          * is partly enforced, and is done so to avoid leaking cookies if certain
 503          * error conditions arise.
 504          *
 505          * This is useful when background scripts inherit context when acting on
 506          * behalf of a user. In general the 'sessionId' parameter should be set
 507          * to an empty string unless session importing is *truly* needed. This
 508          * feature is somewhat deprecated.
 509          *
 510          * @note suhosin.session.encrypt may interfere with this method.
 511          *
 512          * @param array $params Result of RequestContext::exportSession()
 513          * @return ScopedCallback
 514          * @throws MWException
 515          * @since 1.21
 516          */
 517         public static function importScopedSession( array $params ) {
 518                 if ( session_id() != '' && strlen( $params['sessionId'] ) ) {
 519                         // Sanity check to avoid sending random cookies for the wrong users.
 520                         // This method should only called by CLI scripts or by HTTP job runners.
 521                         throw new MWException( "Sessions can only be imported when none is active." );
 522                 } elseif ( !IP::isValid( $params['ip'] ) ) {
 523                         throw new MWException( "Invalid client IP address '{$params['ip']}'." );
 524                 }
 525
 526                 if ( $params['userId'] ) { // logged-in user
 527                         $user = User::newFromId( $params['userId'] );
 528                         $user->load();
 529                         if ( !$user->getId() ) {
 530                                 throw new MWException( "No user with ID '{$params['userId']}'." );
 531                         }
 532                 } else { // anon user
 533                         $user = User::newFromName( $params['ip'], false );
 534                 }
 535
 536                 $importSessionFunc = function ( User $user, array $params ) {
 537                         global $wgRequest, $wgUser;
 538
 539                         $context = RequestContext::getMain();
 540                         // Commit and close any current session
 541                         session_write_close(); // persist
 542                         session_id( '' ); // detach
 543                         $_SESSION = array(); // clear in-memory array
 544                         // Remove any user IP or agent information
 545                         $context->setRequest( new FauxRequest() );
 546                         $wgRequest = $context->getRequest(); // b/c
 547                         // Now that all private information is detached from the user, it should
 548                         // be safe to load the new user. If errors occur or an exception is thrown
 549                         // and caught (leaving the main context in a mixed state), there is no risk
 550                         // of the User object being attached to the wrong IP, headers, or session.
 551                         $context->setUser( $user );
 552                         $wgUser = $context->getUser(); // b/c
 553                         if ( strlen( $params['sessionId'] ) ) { // don't make a new random ID
 554                                 wfSetupSession( $params['sessionId'] ); // sets $_SESSION
 555                         }
 556                         $request = new FauxRequest( array(), false, $_SESSION );
 557                         $request->setIP( $params['ip'] );
 558                         foreach ( $params['headers'] as $name => $value ) {
 559                                 $request->setHeader( $name, $value );
 560                         }
 561                         // Set the current context to use the new WebRequest
 562                         $context->setRequest( $request );
 563                         $wgRequest = $context->getRequest(); // b/c
 564                 };
 565
 566                 // Stash the old session and load in the new one
 567                 $oUser = self::getMain()->getUser();
 568                 $oParams = self::getMain()->exportSession();
 569                 $oRequest = self::getMain()->getRequest();
 570                 $importSessionFunc( $user, $params );
 571
 572                 // Set callback to save and close the new session and reload the old one
 573                 return new ScopedCallback(
 574                         function () use ( $importSessionFunc, $oUser, $oParams, $oRequest ) {
 575                                 global $wgRequest;
 576                                 $importSessionFunc( $oUser, $oParams );
 577                                 // Restore the exact previous Request object (instead of leaving FauxRequest)
 578                                 RequestContext::getMain()->setRequest( $oRequest );
 579                                 $wgRequest = RequestContext::getMain()->getRequest(); // b/c
 580                         }
 581                 );
 582         }
 583
 584         /**
 585          * Create a new extraneous context. The context is filled with information
 586          * external to the current session.
 587          * - Title is specified by argument
 588          * - Request is a FauxRequest, or a FauxRequest can be specified by argument
 589          * - User is an anonymous user, for separation IPv4 localhost is used
 590          * - Language will be based on the anonymous user and request, may be content
 591          *   language or a uselang param in the fauxrequest data may change the lang
 592          * - Skin will be based on the anonymous user, should be the wiki's default skin
 593          *
 594          * @param Title $title Title to use for the extraneous request
 595          * @param WebRequest|array $request A WebRequest or data to use for a FauxRequest
 596          * @return RequestContext
 597          */
 598         public static function newExtraneousContext( Title $title, $request = array() ) {
 599                 $context = new self;
 600                 $context->setTitle( $title );
 601                 if ( $request instanceof WebRequest ) {
 602                         $context->setRequest( $request );
 603                 } else {
 604                         $context->setRequest( new FauxRequest( $request ) );
 605                 }
 606                 $context->user = User::newFromName( '127.0.0.1', false );
 607
 608                 return $context;
 609         }
 610 }