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          * Set the Config object
  73          *
  74          * @param Config $c
  75          */
  76         public function setConfig( Config $c ) {
  77                 $this->config = $c;
  78         }
  79
  80         /**
  81          * Get the Config object
  82          *
  83          * @return Config
  84          */
  85         public function getConfig() {
  86                 if ( $this->config === null ) {
  87                         $this->config = Config::factory();
  88                 }
  89                 return $this->config;
  90         }
  91
  92         /**
  93          * Set the WebRequest object
  94          *
  95          * @param WebRequest $r
  96          */
  97         public function setRequest( WebRequest $r ) {
  98                 $this->request = $r;
  99         }
 100
 101         /**
 102          * Get the WebRequest object
 103          *
 104          * @return WebRequest
 105          */
 106         public function getRequest() {
 107                 if ( $this->request === null ) {
 108                         global $wgRequest; # fallback to $wg till we can improve this
 109                         $this->request = $wgRequest;
 110                 }
 111
 112                 return $this->request;
 113         }
 114
 115         /**
 116          * Set the Title object
 117          *
 118          * @param Title $t
 119          * @throws MWException
 120          */
 121         public function setTitle( $t ) {
 122                 if ( $t !== null && !$t instanceof Title ) {
 123                         throw new MWException( __METHOD__ . " expects an instance of Title" );
 124                 }
 125                 $this->title = $t;
 126                 // Erase the WikiPage so a new one with the new title gets created.
 127                 $this->wikipage = null;
 128         }
 129
 130         /**
 131          * Get the Title object
 132          *
 133          * @return Title
 134          */
 135         public function getTitle() {
 136                 if ( $this->title === null ) {
 137                         global $wgTitle; # fallback to $wg till we can improve this
 138                         $this->title = $wgTitle;
 139                 }
 140
 141                 return $this->title;
 142         }
 143
 144         /**
 145          * Check whether a WikiPage object can be get with getWikiPage().
 146          * Callers should expect that an exception is thrown from getWikiPage()
 147          * if this method returns false.
 148          *
 149          * @since 1.19
 150          * @return bool
 151          */
 152         public function canUseWikiPage() {
 153                 if ( $this->wikipage !== null ) {
 154                         # If there's a WikiPage object set, we can for sure get it
 155                         return true;
 156                 }
 157                 $title = $this->getTitle();
 158                 if ( $title === null ) {
 159                         # No Title, no WikiPage
 160                         return false;
 161                 } else {
 162                         # Only namespaces whose pages are stored in the database can have WikiPage
 163                         return $title->canExist();
 164                 }
 165         }
 166
 167         /**
 168          * Set the WikiPage object
 169          *
 170          * @since 1.19
 171          * @param WikiPage $p
 172          */
 173         public function setWikiPage( WikiPage $p ) {
 174                 $contextTitle = $this->getTitle();
 175                 $pageTitle = $p->getTitle();
 176                 if ( !$contextTitle || !$pageTitle->equals( $contextTitle ) ) {
 177                         $this->setTitle( $pageTitle );
 178                 }
 179                 // Defer this to the end since setTitle sets it to null.
 180                 $this->wikipage = $p;
 181         }
 182
 183         /**
 184          * Get the WikiPage object.
 185          * May throw an exception if there's no Title object set or the Title object
 186          * belongs to a special namespace that doesn't have WikiPage, so use first
 187          * canUseWikiPage() to check whether this method can be called safely.
 188          *
 189          * @since 1.19
 190          * @throws MWException
 191          * @return WikiPage
 192          */
 193         public function getWikiPage() {
 194                 if ( $this->wikipage === null ) {
 195                         $title = $this->getTitle();
 196                         if ( $title === null ) {
 197                                 throw new MWException( __METHOD__ . ' called without Title object set' );
 198                         }
 199                         $this->wikipage = WikiPage::factory( $title );
 200                 }
 201
 202                 return $this->wikipage;
 203         }
 204
 205         /**
 206          * @param $o OutputPage
 207          */
 208         public function setOutput( OutputPage $o ) {
 209                 $this->output = $o;
 210         }
 211
 212         /**
 213          * Get the OutputPage object
 214          *
 215          * @return OutputPage
 216          */
 217         public function getOutput() {
 218                 if ( $this->output === null ) {
 219                         $this->output = new OutputPage( $this );
 220                 }
 221
 222                 return $this->output;
 223         }
 224
 225         /**
 226          * Set the User object
 227          *
 228          * @param User $u
 229          */
 230         public function setUser( User $u ) {
 231                 $this->user = $u;
 232         }
 233
 234         /**
 235          * Get the User object
 236          *
 237          * @return User
 238          */
 239         public function getUser() {
 240                 if ( $this->user === null ) {
 241                         $this->user = User::newFromSession( $this->getRequest() );
 242                 }
 243
 244                 return $this->user;
 245         }
 246
 247         /**
 248          * Accepts a language code and ensures it's sane. Outputs a cleaned up language
 249          * code and replaces with $wgLanguageCode if not sane.
 250          * @param string $code Language code
 251          * @return string
 252          */
 253         public static function sanitizeLangCode( $code ) {
 254                 global $wgLanguageCode;
 255
 256                 // BCP 47 - letter case MUST NOT carry meaning
 257                 $code = strtolower( $code );
 258
 259                 # Validate $code
 260                 if ( empty( $code ) || !Language::isValidCode( $code ) || ( $code === 'qqq' ) ) {
 261                         wfDebug( "Invalid user language code\n" );
 262                         $code = $wgLanguageCode;
 263                 }
 264
 265                 return $code;
 266         }
 267
 268         /**
 269          * Set the Language object
 270          *
 271          * @deprecated since 1.19 Use setLanguage instead
 272          * @param Language|string $l Language instance or language code
 273          */
 274         public function setLang( $l ) {
 275                 wfDeprecated( __METHOD__, '1.19' );
 276                 $this->setLanguage( $l );
 277         }
 278
 279         /**
 280          * Set the Language object
 281          *
 282          * @param Language|string $l Language instance or language code
 283          * @throws MWException
 284          * @since 1.19
 285          */
 286         public function setLanguage( $l ) {
 287                 if ( $l instanceof Language ) {
 288                         $this->lang = $l;
 289                 } elseif ( is_string( $l ) ) {
 290                         $l = self::sanitizeLangCode( $l );
 291                         $obj = Language::factory( $l );
 292                         $this->lang = $obj;
 293                 } else {
 294                         throw new MWException( __METHOD__ . " was passed an invalid type of data." );
 295                 }
 296         }
 297
 298         /**
 299          * @deprecated since 1.19 Use getLanguage instead
 300          * @return Language
 301          */
 302         public function getLang() {
 303                 wfDeprecated( __METHOD__, '1.19' );
 304
 305                 return $this->getLanguage();
 306         }
 307
 308         /**
 309          * Get the Language object.
 310          * Initialization of user or request objects can depend on this.
 311          *
 312          * @return Language
 313          * @since 1.19
 314          */
 315         public function getLanguage() {
 316                 if ( isset( $this->recursion ) ) {
 317                         trigger_error( "Recursion detected in " . __METHOD__, E_USER_WARNING );
 318                         $e = new Exception;
 319                         wfDebugLog( 'recursion-guard', "Recursion detected:\n" . $e->getTraceAsString() );
 320
 321                         global $wgLanguageCode;
 322                         $code = ( $wgLanguageCode ) ? $wgLanguageCode : 'en';
 323                         $this->lang = Language::factory( $code );
 324                 } elseif ( $this->lang === null ) {
 325                         $this->recursion = true;
 326
 327                         global $wgLanguageCode, $wgContLang;
 328
 329                         $request = $this->getRequest();
 330                         $user = $this->getUser();
 331
 332                         $code = $request->getVal( 'uselang', $user->getOption( 'language' ) );
 333                         $code = self::sanitizeLangCode( $code );
 334
 335                         wfRunHooks( 'UserGetLanguageObject', array( $user, &$code, $this ) );
 336
 337                         if ( $code === $wgLanguageCode ) {
 338                                 $this->lang = $wgContLang;
 339                         } else {
 340                                 $obj = Language::factory( $code );
 341                                 $this->lang = $obj;
 342                         }
 343
 344                         unset( $this->recursion );
 345                 }
 346
 347                 return $this->lang;
 348         }
 349
 350         /**
 351          * Set the Skin object
 352          *
 353          * @param Skin $s
 354          */
 355         public function setSkin( Skin $s ) {
 356                 $this->skin = clone $s;
 357                 $this->skin->setContext( $this );
 358         }
 359
 360         /**
 361          * Get the Skin object
 362          *
 363          * @return Skin
 364          */
 365         public function getSkin() {
 366                 if ( $this->skin === null ) {
 367                         wfProfileIn( __METHOD__ . '-createskin' );
 368
 369                         $skin = null;
 370                         wfRunHooks( 'RequestContextCreateSkin', array( $this, &$skin ) );
 371
 372                         // If the hook worked try to set a skin from it
 373                         if ( $skin instanceof Skin ) {
 374                                 $this->skin = $skin;
 375                         } elseif ( is_string( $skin ) ) {
 376                                 $this->skin = Skin::newFromKey( $skin );
 377                         }
 378
 379                         // If this is still null (the hook didn't run or didn't work)
 380                         // then go through the normal processing to load a skin
 381                         if ( $this->skin === null ) {
 382                                 global $wgHiddenPrefs;
 383                                 if ( !in_array( 'skin', $wgHiddenPrefs ) ) {
 384                                         # get the user skin
 385                                         $userSkin = $this->getUser()->getOption( 'skin' );
 386                                         $userSkin = $this->getRequest()->getVal( 'useskin', $userSkin );
 387                                 } else {
 388                                         # if we're not allowing users to override, then use the default
 389                                         global $wgDefaultSkin;
 390                                         $userSkin = $wgDefaultSkin;
 391                                 }
 392
 393                                 $this->skin = Skin::newFromKey( $userSkin );
 394                         }
 395
 396                         // After all that set a context on whatever skin got created
 397                         $this->skin->setContext( $this );
 398                         wfProfileOut( __METHOD__ . '-createskin' );
 399                 }
 400
 401                 return $this->skin;
 402         }
 403
 404         /** Helpful methods **/
 405
 406         /**
 407          * Get a Message object with context set
 408          * Parameters are the same as wfMessage()
 409          *
 410          * @return Message
 411          */
 412         public function msg() {
 413                 $args = func_get_args();
 414
 415                 return call_user_func_array( 'wfMessage', $args )->setContext( $this );
 416         }
 417
 418         /** Static methods **/
 419
 420         /**
 421          * Get the RequestContext object associated with the main request
 422          *
 423          * @return RequestContext
 424          */
 425         public static function getMain() {
 426                 static $instance = null;
 427                 if ( $instance === null ) {
 428                         $instance = new self;
 429                 }
 430
 431                 return $instance;
 432         }
 433
 434         /**
 435          * Export the resolved user IP, HTTP headers, user ID, and session ID.
 436          * The result will be reasonably sized to allow for serialization.
 437          *
 438          * @return Array
 439          * @since 1.21
 440          */
 441         public function exportSession() {
 442                 return array(
 443                         'ip' => $this->getRequest()->getIP(),
 444                         'headers' => $this->getRequest()->getAllHeaders(),
 445                         'sessionId' => session_id(),
 446                         'userId' => $this->getUser()->getId()
 447                 );
 448         }
 449
 450         /**
 451          * Import the resolved user IP, HTTP headers, user ID, and session ID.
 452          * This sets the current session and sets $wgUser and $wgRequest.
 453          * Once the return value falls out of scope, the old context is restored.
 454          * This function can only be called within CLI mode scripts.
 455          *
 456          * This will setup the session from the given ID. This is useful when
 457          * background scripts inherit context when acting on behalf of a user.
 458          *
 459          * @note suhosin.session.encrypt may interfere with this method.
 460          *
 461          * @param array $params Result of RequestContext::exportSession()
 462          * @return ScopedCallback
 463          * @throws MWException
 464          * @since 1.21
 465          */
 466         public static function importScopedSession( array $params ) {
 467                 if ( PHP_SAPI !== 'cli' ) {
 468                         // Don't send random private cookies or turn $wgRequest into FauxRequest
 469                         throw new MWException( "Sessions can only be imported in cli mode." );
 470                 } elseif ( !strlen( $params['sessionId'] ) ) {
 471                         throw new MWException( "No session ID was specified." );
 472                 }
 473
 474                 if ( $params['userId'] ) { // logged-in user
 475                         $user = User::newFromId( $params['userId'] );
 476                         if ( !$user ) {
 477                                 throw new MWException( "No user with ID '{$params['userId']}'." );
 478                         }
 479                 } elseif ( !IP::isValid( $params['ip'] ) ) {
 480                         throw new MWException( "Could not load user '{$params['ip']}'." );
 481                 } else { // anon user
 482                         $user = User::newFromName( $params['ip'], false );
 483                 }
 484
 485                 $importSessionFunction = function ( User $user, array $params ) {
 486                         global $wgRequest, $wgUser;
 487
 488                         $context = RequestContext::getMain();
 489                         // Commit and close any current session
 490                         session_write_close(); // persist
 491                         session_id( '' ); // detach
 492                         $_SESSION = array(); // clear in-memory array
 493                         // Remove any user IP or agent information
 494                         $context->setRequest( new FauxRequest() );
 495                         $wgRequest = $context->getRequest(); // b/c
 496                         // Now that all private information is detached from the user, it should
 497                         // be safe to load the new user. If errors occur or an exception is thrown
 498                         // and caught (leaving the main context in a mixed state), there is no risk
 499                         // of the User object being attached to the wrong IP, headers, or session.
 500                         $context->setUser( $user );
 501                         $wgUser = $context->getUser(); // b/c
 502                         if ( strlen( $params['sessionId'] ) ) { // don't make a new random ID
 503                                 wfSetupSession( $params['sessionId'] ); // sets $_SESSION
 504                         }
 505                         $request = new FauxRequest( array(), false, $_SESSION );
 506                         $request->setIP( $params['ip'] );
 507                         foreach ( $params['headers'] as $name => $value ) {
 508                                 $request->setHeader( $name, $value );
 509                         }
 510                         // Set the current context to use the new WebRequest
 511                         $context->setRequest( $request );
 512                         $wgRequest = $context->getRequest(); // b/c
 513                 };
 514
 515                 // Stash the old session and load in the new one
 516                 $oUser = self::getMain()->getUser();
 517                 $oParams = self::getMain()->exportSession();
 518                 $importSessionFunction( $user, $params );
 519
 520                 // Set callback to save and close the new session and reload the old one
 521                 return new ScopedCallback( function () use ( $importSessionFunction, $oUser, $oParams ) {
 522                         $importSessionFunction( $oUser, $oParams );
 523                 } );
 524         }
 525
 526         /**
 527          * Create a new extraneous context. The context is filled with information
 528          * external to the current session.
 529          * - Title is specified by argument
 530          * - Request is a FauxRequest, or a FauxRequest can be specified by argument
 531          * - User is an anonymous user, for separation IPv4 localhost is used
 532          * - Language will be based on the anonymous user and request, may be content
 533          *   language or a uselang param in the fauxrequest data may change the lang
 534          * - Skin will be based on the anonymous user, should be the wiki's default skin
 535          *
 536          * @param Title $title Title to use for the extraneous request
 537          * @param WebRequest|array $request A WebRequest or data to use for a FauxRequest
 538          * @return RequestContext
 539          */
 540         public static function newExtraneousContext( Title $title, $request = array() ) {
 541                 $context = new self;
 542                 $context->setTitle( $title );
 543                 if ( $request instanceof WebRequest ) {
 544                         $context->setRequest( $request );
 545                 } else {
 546                         $context->setRequest( new FauxRequest( $request ) );
 547                 }
 548                 $context->user = User::newFromName( '127.0.0.1', false );
 549
 550                 return $context;
 551         }
 552 }