includes/context/RequestContext.php

   1 <?php
   2 /**
   3  * Request-dependant objects containers.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @since 1.18
  21  *
  22  * @author Alexandre Emsenhuber
  23  * @author Daniel Friesen
  24  * @file
  25  */
  26
  27 /**
  28  * Group all the pieces relevant to the context of a request into one instance
  29  */
  30 class RequestContext implements IContextSource {
  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 Config
  68          */
  69         private $config;
  70
  71         /**
  72          * @var RequestContext
  73          */
  74         private static $instance = null;
  75
  76         /**
  77          * Set the Config object
  78          *
  79          * @param Config $c
  80          */
  81         public function setConfig( Config $c ) {
  82                 $this->config = $c;
  83         }
  84
  85         /**
  86          * Get the Config object
  87          *
  88          * @return Config
  89          */
  90         public function getConfig() {
  91                 if ( $this->config === null ) {
  92                         // @todo In the future, we could move this to WebStart.php so
  93                         // the Config object is ready for when initialization happens
  94                         $this->config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
  95                 }
  96
  97                 return $this->config;
  98         }
  99
 100         /**
 101          * Set the WebRequest object
 102          *
 103          * @param WebRequest $r
 104          */
 105         public function setRequest( WebRequest $r ) {
 106                 $this->request = $r;
 107         }
 108
 109         /**
 110          * Get the WebRequest object
 111          *
 112          * @return WebRequest
 113          */
 114         public function getRequest() {
 115                 if ( $this->request === null ) {
 116                         global $wgRequest; # fallback to $wg till we can improve this
 117                         $this->request = $wgRequest;
 118                 }
 119
 120                 return $this->request;
 121         }
 122
 123         /**
 124          * Set the Title object
 125          *
 126          * @param Title $t
 127          */
 128         public function setTitle( Title $t ) {
 129                 $this->title = $t;
 130                 // Erase the WikiPage so a new one with the new title gets created.
 131                 $this->wikipage = null;
 132         }
 133
 134         /**
 135          * Get the Title object
 136          *
 137          * @return Title|null
 138          */
 139         public function getTitle() {
 140                 if ( $this->title === null ) {
 141                         global $wgTitle; # fallback to $wg till we can improve this
 142                         $this->title = $wgTitle;
 143                 }
 144
 145                 return $this->title;
 146         }
 147
 148         /**
 149          * Check whether a WikiPage object can be get with getWikiPage().
 150          * Callers should expect that an exception is thrown from getWikiPage()
 151          * if this method returns false.
 152          *
 153          * @since 1.19
 154          * @return bool
 155          */
 156         public function canUseWikiPage() {
 157                 if ( $this->wikipage !== null ) {
 158                         # If there's a WikiPage object set, we can for sure get it
 159                         return true;
 160                 }
 161                 $title = $this->getTitle();
 162                 if ( $title === null ) {
 163                         # No Title, no WikiPage
 164                         return false;
 165                 } else {
 166                         # Only namespaces whose pages are stored in the database can have WikiPage
 167                         return $title->canExist();
 168                 }
 169         }
 170
 171         /**
 172          * Set the WikiPage object
 173          *
 174          * @since 1.19
 175          * @param WikiPage $p
 176          */
 177         public function setWikiPage( WikiPage $p ) {
 178                 $contextTitle = $this->getTitle();
 179                 $pageTitle = $p->getTitle();
 180                 if ( !$contextTitle || !$pageTitle->equals( $contextTitle ) ) {
 181                         $this->setTitle( $pageTitle );
 182                 }
 183                 // Defer this to the end since setTitle sets it to null.
 184                 $this->wikipage = $p;
 185         }
 186
 187         /**
 188          * Get the WikiPage object.
 189          * May throw an exception if there's no Title object set or the Title object
 190          * belongs to a special namespace that doesn't have WikiPage, so use first
 191          * canUseWikiPage() to check whether this method can be called safely.
 192          *
 193          * @since 1.19
 194          * @throws MWException
 195          * @return WikiPage
 196          */
 197         public function getWikiPage() {
 198                 if ( $this->wikipage === null ) {
 199                         $title = $this->getTitle();
 200                         if ( $title === null ) {
 201                                 throw new MWException( __METHOD__ . ' called without Title object set' );
 202                         }
 203                         $this->wikipage = WikiPage::factory( $title );
 204                 }
 205
 206                 return $this->wikipage;
 207         }
 208
 209         /**
 210          * @param OutputPage $o
 211          */
 212         public function setOutput( OutputPage $o ) {
 213                 $this->output = $o;
 214         }
 215
 216         /**
 217          * Get the OutputPage object
 218          *
 219          * @return OutputPage
 220          */
 221         public function getOutput() {
 222                 if ( $this->output === null ) {
 223                         $this->output = new OutputPage( $this );
 224                 }
 225
 226                 return $this->output;
 227         }
 228
 229         /**
 230          * Set the User object
 231          *
 232          * @param User $u
 233          */
 234         public function setUser( User $u ) {
 235                 $this->user = $u;
 236         }
 237
 238         /**
 239          * Get the User object
 240          *
 241          * @return User
 242          */
 243         public function getUser() {
 244                 if ( $this->user === null ) {
 245                         $this->user = User::newFromSession( $this->getRequest() );
 246                 }
 247
 248                 return $this->user;
 249         }
 250
 251         /**
 252          * Accepts a language code and ensures it's sane. Outputs a cleaned up language
 253          * code and replaces with $wgLanguageCode if not sane.
 254          * @param string $code Language code
 255          * @return string
 256          */
 257         public static function sanitizeLangCode( $code ) {
 258                 global $wgLanguageCode;
 259
 260                 // BCP 47 - letter case MUST NOT carry meaning
 261                 $code = strtolower( $code );
 262
 263                 # Validate $code
 264                 if ( empty( $code ) || !Language::isValidCode( $code ) || ( $code === 'qqq' ) ) {
 265                         wfDebug( "Invalid user language code\n" );
 266                         $code = $wgLanguageCode;
 267                 }
 268
 269                 return $code;
 270         }
 271
 272         /**
 273          * Set the Language object
 274          *
 275          * @param Language|string $l Language instance or language code
 276          * @throws MWException
 277          * @since 1.19
 278          */
 279         public function setLanguage( $l ) {
 280                 if ( $l instanceof Language ) {
 281                         $this->lang = $l;
 282                 } elseif ( is_string( $l ) ) {
 283                         $l = self::sanitizeLangCode( $l );
 284                         $obj = Language::factory( $l );
 285                         $this->lang = $obj;
 286                 } else {
 287                         throw new MWException( __METHOD__ . " was passed an invalid type of data." );
 288                 }
 289         }
 290
 291         /**
 292          * Get the Language object.
 293          * Initialization of user or request objects can depend on this.
 294          *
 295          * @return Language
 296          * @since 1.19
 297          */
 298         public function getLanguage() {
 299                 if ( isset( $this->recursion ) ) {
 300                         trigger_error( "Recursion detected in " . __METHOD__, E_USER_WARNING );
 301                         $e = new Exception;
 302                         wfDebugLog( 'recursion-guard', "Recursion detected:\n" . $e->getTraceAsString() );
 303
 304                         global $wgLanguageCode;
 305                         $code = ( $wgLanguageCode ) ? $wgLanguageCode : 'en';
 306                         $this->lang = Language::factory( $code );
 307                 } elseif ( $this->lang === null ) {
 308                         $this->recursion = true;
 309
 310                         global $wgLanguageCode, $wgContLang;
 311
 312                         try {
 313                                 $request = $this->getRequest();
 314                                 $user = $this->getUser();
 315
 316                                 $code = $request->getVal( 'uselang', $user->getOption( 'language' ) );
 317                                 $code = self::sanitizeLangCode( $code );
 318
 319                                 wfRunHooks( 'UserGetLanguageObject', array( $user, &$code, $this ) );
 320
 321                                 if ( $code === $wgLanguageCode ) {
 322                                         $this->lang = $wgContLang;
 323                                 } else {
 324                                         $obj = Language::factory( $code );
 325                                         $this->lang = $obj;
 326                                 }
 327
 328                                 unset( $this->recursion );
 329                         }
 330                         catch ( Exception $ex ) {
 331                                 unset( $this->recursion );
 332                                 throw $ex;
 333                         }
 334                 }
 335
 336                 return $this->lang;
 337         }
 338
 339         /**
 340          * Set the Skin object
 341          *
 342          * @param Skin $s
 343          */
 344         public function setSkin( Skin $s ) {
 345                 $this->skin = clone $s;
 346                 $this->skin->setContext( $this );
 347         }
 348
 349         /**
 350          * Get the Skin object
 351          *
 352          * @return Skin
 353          */
 354         public function getSkin() {
 355                 if ( $this->skin === null ) {
 356                         wfProfileIn( __METHOD__ . '-createskin' );
 357
 358                         $skin = null;
 359                         wfRunHooks( 'RequestContextCreateSkin', array( $this, &$skin ) );
 360
 361                         // If the hook worked try to set a skin from it
 362                         if ( $skin instanceof Skin ) {
 363                                 $this->skin = $skin;
 364                         } elseif ( is_string( $skin ) ) {
 365                                 $this->skin = Skin::newFromKey( $skin );
 366                         }
 367
 368                         // If this is still null (the hook didn't run or didn't work)
 369                         // then go through the normal processing to load a skin
 370                         if ( $this->skin === null ) {
 371                                 global $wgHiddenPrefs;
 372                                 if ( !in_array( 'skin', $wgHiddenPrefs ) ) {
 373                                         # get the user skin
 374                                         $userSkin = $this->getUser()->getOption( 'skin' );
 375                                         $userSkin = $this->getRequest()->getVal( 'useskin', $userSkin );
 376                                 } else {
 377                                         # if we're not allowing users to override, then use the default
 378                                         global $wgDefaultSkin;
 379                                         $userSkin = $wgDefaultSkin;
 380                                 }
 381
 382                                 $this->skin = Skin::newFromKey( $userSkin );
 383                         }
 384
 385                         // After all that set a context on whatever skin got created
 386                         $this->skin->setContext( $this );
 387                         wfProfileOut( __METHOD__ . '-createskin' );
 388                 }
 389
 390                 return $this->skin;
 391         }
 392
 393         /** Helpful methods **/
 394
 395         /**
 396          * Get a Message object with context set
 397          * Parameters are the same as wfMessage()
 398          *
 399          * @return Message
 400          */
 401         public function msg() {
 402                 $args = func_get_args();
 403
 404                 return call_user_func_array( 'wfMessage', $args )->setContext( $this );
 405         }
 406
 407         /** Static methods **/
 408
 409         /**
 410          * Get the RequestContext object associated with the main request
 411          *
 412          * @return RequestContext
 413          */
 414         public static function getMain() {
 415                 if ( self::$instance === null ) {
 416                         self::$instance = new self;
 417                 }
 418
 419                 return self::$instance;
 420         }
 421
 422         /**
 423          * Resets singleton returned by getMain(). Should be called only from unit tests.
 424          */
 425         public static function resetMain() {
 426                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
 427                         throw new MWException( __METHOD__ . '() should be called only from unit tests!' );
 428                 }
 429                 self::$instance = null;
 430         }
 431
 432         /**
 433          * Export the resolved user IP, HTTP headers, user ID, and session ID.
 434          * The result will be reasonably sized to allow for serialization.
 435          *
 436          * @return array
 437          * @since 1.21
 438          */
 439         public function exportSession() {
 440                 return array(
 441                         'ip' => $this->getRequest()->getIP(),
 442                         'headers' => $this->getRequest()->getAllHeaders(),
 443                         'sessionId' => session_id(),
 444                         'userId' => $this->getUser()->getId()
 445                 );
 446         }
 447
 448         /**
 449          * Import the resolved user IP, HTTP headers, user ID, and session ID.
 450          * This sets the current session and sets $wgUser and $wgRequest.
 451          * Once the return value falls out of scope, the old context is restored.
 452          * This function can only be called within CLI mode scripts.
 453          *
 454          * This will setup the session from the given ID. This is useful when
 455          * background scripts inherit context when acting on behalf of a user.
 456          *
 457          * @note suhosin.session.encrypt may interfere with this method.
 458          *
 459          * @param array $params Result of RequestContext::exportSession()
 460          * @return ScopedCallback
 461          * @throws MWException
 462          * @since 1.21
 463          */
 464         public static function importScopedSession( array $params ) {
 465                 if ( PHP_SAPI !== 'cli' ) {
 466                         // Don't send random private cookies or turn $wgRequest into FauxRequest
 467                         throw new MWException( "Sessions can only be imported in cli mode." );
 468                 } elseif ( !strlen( $params['sessionId'] ) ) {
 469                         throw new MWException( "No session ID was specified." );
 470                 }
 471
 472                 if ( $params['userId'] ) { // logged-in user
 473                         $user = User::newFromId( $params['userId'] );
 474                         $user->load();
 475                         if ( !$user->getId() ) {
 476                                 throw new MWException( "No user with ID '{$params['userId']}'." );
 477                         }
 478                 } elseif ( !IP::isValid( $params['ip'] ) ) {
 479                         throw new MWException( "Could not load user '{$params['ip']}'." );
 480                 } else { // anon user
 481                         $user = User::newFromName( $params['ip'], false );
 482                 }
 483
 484                 $importSessionFunction = function ( User $user, array $params ) {
 485                         global $wgRequest, $wgUser;
 486
 487                         $context = RequestContext::getMain();
 488                         // Commit and close any current session
 489                         session_write_close(); // persist
 490                         session_id( '' ); // detach
 491                         $_SESSION = array(); // clear in-memory array
 492                         // Remove any user IP or agent information
 493                         $context->setRequest( new FauxRequest() );
 494                         $wgRequest = $context->getRequest(); // b/c
 495                         // Now that all private information is detached from the user, it should
 496                         // be safe to load the new user. If errors occur or an exception is thrown
 497                         // and caught (leaving the main context in a mixed state), there is no risk
 498                         // of the User object being attached to the wrong IP, headers, or session.
 499                         $context->setUser( $user );
 500                         $wgUser = $context->getUser(); // b/c
 501                         if ( strlen( $params['sessionId'] ) ) { // don't make a new random ID
 502                                 wfSetupSession( $params['sessionId'] ); // sets $_SESSION
 503                         }
 504                         $request = new FauxRequest( array(), false, $_SESSION );
 505                         $request->setIP( $params['ip'] );
 506                         foreach ( $params['headers'] as $name => $value ) {
 507                                 $request->setHeader( $name, $value );
 508                         }
 509                         // Set the current context to use the new WebRequest
 510                         $context->setRequest( $request );
 511                         $wgRequest = $context->getRequest(); // b/c
 512                 };
 513
 514                 // Stash the old session and load in the new one
 515                 $oUser = self::getMain()->getUser();
 516                 $oParams = self::getMain()->exportSession();
 517                 $importSessionFunction( $user, $params );
 518
 519                 // Set callback to save and close the new session and reload the old one
 520                 return new ScopedCallback( function () use ( $importSessionFunction, $oUser, $oParams ) {
 521                         $importSessionFunction( $oUser, $oParams );
 522                 } );
 523         }
 524
 525         /**
 526          * Create a new extraneous context. The context is filled with information
 527          * external to the current session.
 528          * - Title is specified by argument
 529          * - Request is a FauxRequest, or a FauxRequest can be specified by argument
 530          * - User is an anonymous user, for separation IPv4 localhost is used
 531          * - Language will be based on the anonymous user and request, may be content
 532          *   language or a uselang param in the fauxrequest data may change the lang
 533          * - Skin will be based on the anonymous user, should be the wiki's default skin
 534          *
 535          * @param Title $title Title to use for the extraneous request
 536          * @param WebRequest|array $request A WebRequest or data to use for a FauxRequest
 537          * @return RequestContext
 538          */
 539         public static function newExtraneousContext( Title $title, $request = array() ) {
 540                 $context = new self;
 541                 $context->setTitle( $title );
 542                 if ( $request instanceof WebRequest ) {
 543                         $context->setRequest( $request );
 544                 } else {
 545                         $context->setRequest( new FauxRequest( $request ) );
 546                 }
 547                 $context->user = User::newFromName( '127.0.0.1', false );
 548
 549                 return $context;
 550         }
 551 }