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