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
  90                 return $this->config;
  91         }
  92
  93         /**
  94          * Set the WebRequest object
  95          *
  96          * @param WebRequest $r
  97          */
  98         public function setRequest( WebRequest $r ) {
  99                 $this->request = $r;
 100         }
 101
 102         /**
 103          * Get the WebRequest object
 104          *
 105          * @return WebRequest
 106          */
 107         public function getRequest() {
 108                 if ( $this->request === null ) {
 109                         global $wgRequest; # fallback to $wg till we can improve this
 110                         $this->request = $wgRequest;
 111                 }
 112
 113                 return $this->request;
 114         }
 115
 116         /**
 117          * Set the Title object
 118          *
 119          * @param Title $t
 120          * @throws MWException
 121          */
 122         public function setTitle( $t ) {
 123                 if ( $t !== null && !$t instanceof Title ) {
 124                         throw new MWException( __METHOD__ . " expects an instance of Title" );
 125                 }
 126                 $this->title = $t;
 127                 // Erase the WikiPage so a new one with the new title gets created.
 128                 $this->wikipage = null;
 129         }
 130
 131         /**
 132          * Get the Title object
 133          *
 134          * @return Title
 135          */
 136         public function getTitle() {
 137                 if ( $this->title === null ) {
 138                         global $wgTitle; # fallback to $wg till we can improve this
 139                         $this->title = $wgTitle;
 140                 }
 141
 142                 return $this->title;
 143         }
 144
 145         /**
 146          * Check whether a WikiPage object can be get with getWikiPage().
 147          * Callers should expect that an exception is thrown from getWikiPage()
 148          * if this method returns false.
 149          *
 150          * @since 1.19
 151          * @return bool
 152          */
 153         public function canUseWikiPage() {
 154                 if ( $this->wikipage !== null ) {
 155                         # If there's a WikiPage object set, we can for sure get it
 156                         return true;
 157                 }
 158                 $title = $this->getTitle();
 159                 if ( $title === null ) {
 160                         # No Title, no WikiPage
 161                         return false;
 162                 } else {
 163                         # Only namespaces whose pages are stored in the database can have WikiPage
 164                         return $title->canExist();
 165                 }
 166         }
 167
 168         /**
 169          * Set the WikiPage object
 170          *
 171          * @since 1.19
 172          * @param WikiPage $p
 173          */
 174         public function setWikiPage( WikiPage $p ) {
 175                 $contextTitle = $this->getTitle();
 176                 $pageTitle = $p->getTitle();
 177                 if ( !$contextTitle || !$pageTitle->equals( $contextTitle ) ) {
 178                         $this->setTitle( $pageTitle );
 179                 }
 180                 // Defer this to the end since setTitle sets it to null.
 181                 $this->wikipage = $p;
 182         }
 183
 184         /**
 185          * Get the WikiPage object.
 186          * May throw an exception if there's no Title object set or the Title object
 187          * belongs to a special namespace that doesn't have WikiPage, so use first
 188          * canUseWikiPage() to check whether this method can be called safely.
 189          *
 190          * @since 1.19
 191          * @throws MWException
 192          * @return WikiPage
 193          */
 194         public function getWikiPage() {
 195                 if ( $this->wikipage === null ) {
 196                         $title = $this->getTitle();
 197                         if ( $title === null ) {
 198                                 throw new MWException( __METHOD__ . ' called without Title object set' );
 199                         }
 200                         $this->wikipage = WikiPage::factory( $title );
 201                 }
 202
 203                 return $this->wikipage;
 204         }
 205
 206         /**
 207          * @param OutputPage $o
 208          */
 209         public function setOutput( OutputPage $o ) {
 210                 $this->output = $o;
 211         }
 212
 213         /**
 214          * Get the OutputPage object
 215          *
 216          * @return OutputPage
 217          */
 218         public function getOutput() {
 219                 if ( $this->output === null ) {
 220                         $this->output = new OutputPage( $this );
 221                 }
 222
 223                 return $this->output;
 224         }
 225
 226         /**
 227          * Set the User object
 228          *
 229          * @param User $u
 230          */
 231         public function setUser( User $u ) {
 232                 $this->user = $u;
 233         }
 234
 235         /**
 236          * Get the User object
 237          *
 238          * @return User
 239          */
 240         public function getUser() {
 241                 if ( $this->user === null ) {
 242                         $this->user = User::newFromSession( $this->getRequest() );
 243                 }
 244
 245                 return $this->user;
 246         }
 247
 248         /**
 249          * Accepts a language code and ensures it's sane. Outputs a cleaned up language
 250          * code and replaces with $wgLanguageCode if not sane.
 251          * @param string $code Language code
 252          * @return string
 253          */
 254         public static function sanitizeLangCode( $code ) {
 255                 global $wgLanguageCode;
 256
 257                 // BCP 47 - letter case MUST NOT carry meaning
 258                 $code = strtolower( $code );
 259
 260                 # Validate $code
 261                 if ( empty( $code ) || !Language::isValidCode( $code ) || ( $code === 'qqq' ) ) {
 262                         wfDebug( "Invalid user language code\n" );
 263                         $code = $wgLanguageCode;
 264                 }
 265
 266                 return $code;
 267         }
 268
 269         /**
 270          * Set the Language object
 271          *
 272          * @deprecated since 1.19 Use setLanguage instead
 273          * @param Language|string $l Language instance or language code
 274          */
 275         public function setLang( $l ) {
 276                 wfDeprecated( __METHOD__, '1.19' );
 277                 $this->setLanguage( $l );
 278         }
 279
 280         /**
 281          * Set the Language object
 282          *
 283          * @param Language|string $l Language instance or language code
 284          * @throws MWException
 285          * @since 1.19
 286          */
 287         public function setLanguage( $l ) {
 288                 if ( $l instanceof Language ) {
 289                         $this->lang = $l;
 290                 } elseif ( is_string( $l ) ) {
 291                         $l = self::sanitizeLangCode( $l );
 292                         $obj = Language::factory( $l );
 293                         $this->lang = $obj;
 294                 } else {
 295                         throw new MWException( __METHOD__ . " was passed an invalid type of data." );
 296                 }
 297         }
 298
 299         /**
 300          * @deprecated since 1.19 Use getLanguage instead
 301          * @return Language
 302          */
 303         public function getLang() {
 304                 wfDeprecated( __METHOD__, '1.19' );
 305
 306                 return $this->getLanguage();
 307         }
 308
 309         /**
 310          * Get the Language object.
 311          * Initialization of user or request objects can depend on this.
 312          *
 313          * @return Language
 314          * @since 1.19
 315          */
 316         public function getLanguage() {
 317                 if ( isset( $this->recursion ) ) {
 318                         trigger_error( "Recursion detected in " . __METHOD__, E_USER_WARNING );
 319                         $e = new Exception;
 320                         wfDebugLog( 'recursion-guard', "Recursion detected:\n" . $e->getTraceAsString() );
 321
 322                         global $wgLanguageCode;
 323                         $code = ( $wgLanguageCode ) ? $wgLanguageCode : 'en';
 324                         $this->lang = Language::factory( $code );
 325                 } elseif ( $this->lang === null ) {
 326                         $this->recursion = true;
 327
 328                         global $wgLanguageCode, $wgContLang;
 329
 330                         $request = $this->getRequest();
 331                         $user = $this->getUser();
 332
 333                         $code = $request->getVal( 'uselang', $user->getOption( 'language' ) );
 334                         $code = self::sanitizeLangCode( $code );
 335
 336                         wfRunHooks( 'UserGetLanguageObject', array( $user, &$code, $this ) );
 337
 338                         if ( $code === $wgLanguageCode ) {
 339                                 $this->lang = $wgContLang;
 340                         } else {
 341                                 $obj = Language::factory( $code );
 342                                 $this->lang = $obj;
 343                         }
 344
 345                         unset( $this->recursion );
 346                 }
 347
 348                 return $this->lang;
 349         }
 350
 351         /**
 352          * Set the Skin object
 353          *
 354          * @param Skin $s
 355          */
 356         public function setSkin( Skin $s ) {
 357                 $this->skin = clone $s;
 358                 $this->skin->setContext( $this );
 359         }
 360
 361         /**
 362          * Get the Skin object
 363          *
 364          * @return Skin
 365          */
 366         public function getSkin() {
 367                 if ( $this->skin === null ) {
 368                         wfProfileIn( __METHOD__ . '-createskin' );
 369
 370                         $skin = null;
 371                         wfRunHooks( 'RequestContextCreateSkin', array( $this, &$skin ) );
 372
 373                         // If the hook worked try to set a skin from it
 374                         if ( $skin instanceof Skin ) {
 375                                 $this->skin = $skin;
 376                         } elseif ( is_string( $skin ) ) {
 377                                 $this->skin = Skin::newFromKey( $skin );
 378                         }
 379
 380                         // If this is still null (the hook didn't run or didn't work)
 381                         // then go through the normal processing to load a skin
 382                         if ( $this->skin === null ) {
 383                                 global $wgHiddenPrefs;
 384                                 if ( !in_array( 'skin', $wgHiddenPrefs ) ) {
 385                                         # get the user skin
 386                                         $userSkin = $this->getUser()->getOption( 'skin' );
 387                                         $userSkin = $this->getRequest()->getVal( 'useskin', $userSkin );
 388                                 } else {
 389                                         # if we're not allowing users to override, then use the default
 390                                         global $wgDefaultSkin;
 391                                         $userSkin = $wgDefaultSkin;
 392                                 }
 393
 394                                 $this->skin = Skin::newFromKey( $userSkin );
 395                         }
 396
 397                         // After all that set a context on whatever skin got created
 398                         $this->skin->setContext( $this );
 399                         wfProfileOut( __METHOD__ . '-createskin' );
 400                 }
 401
 402                 return $this->skin;
 403         }
 404
 405         /** Helpful methods **/
 406
 407         /**
 408          * Get a Message object with context set
 409          * Parameters are the same as wfMessage()
 410          *
 411          * @return Message
 412          */
 413         public function msg() {
 414                 $args = func_get_args();
 415
 416                 return call_user_func_array( 'wfMessage', $args )->setContext( $this );
 417         }
 418
 419         /** Static methods **/
 420
 421         /**
 422          * Get the RequestContext object associated with the main request
 423          *
 424          * @return RequestContext
 425          */
 426         public static function getMain() {
 427                 static $instance = null;
 428                 if ( $instance === null ) {
 429                         $instance = new self;
 430                 }
 431
 432                 return $instance;
 433         }
 434
 435         /**
 436          * Export the resolved user IP, HTTP headers, user ID, and session ID.
 437          * The result will be reasonably sized to allow for serialization.
 438          *
 439          * @return array
 440          * @since 1.21
 441          */
 442         public function exportSession() {
 443                 return array(
 444                         'ip' => $this->getRequest()->getIP(),
 445                         'headers' => $this->getRequest()->getAllHeaders(),
 446                         'sessionId' => session_id(),
 447                         'userId' => $this->getUser()->getId()
 448                 );
 449         }
 450
 451         /**
 452          * Import the resolved user IP, HTTP headers, user ID, and session ID.
 453          * This sets the current session and sets $wgUser and $wgRequest.
 454          * Once the return value falls out of scope, the old context is restored.
 455          * This function can only be called within CLI mode scripts.
 456          *
 457          * This will setup the session from the given ID. This is useful when
 458          * background scripts inherit context when acting on behalf of a user.
 459          *
 460          * @note suhosin.session.encrypt may interfere with this method.
 461          *
 462          * @param array $params Result of RequestContext::exportSession()
 463          * @return ScopedCallback
 464          * @throws MWException
 465          * @since 1.21
 466          */
 467         public static function importScopedSession( array $params ) {
 468                 if ( PHP_SAPI !== 'cli' ) {
 469                         // Don't send random private cookies or turn $wgRequest into FauxRequest
 470                         throw new MWException( "Sessions can only be imported in cli mode." );
 471                 } elseif ( !strlen( $params['sessionId'] ) ) {
 472                         throw new MWException( "No session ID was specified." );
 473                 }
 474
 475                 if ( $params['userId'] ) { // logged-in user
 476                         $user = User::newFromId( $params['userId'] );
 477                         if ( !$user ) {
 478                                 throw new MWException( "No user with ID '{$params['userId']}'." );
 479                         }
 480                 } elseif ( !IP::isValid( $params['ip'] ) ) {
 481                         throw new MWException( "Could not load user '{$params['ip']}'." );
 482                 } else { // anon user
 483                         $user = User::newFromName( $params['ip'], false );
 484                 }
 485
 486                 $importSessionFunction = function ( User $user, array $params ) {
 487                         global $wgRequest, $wgUser;
 488
 489                         $context = RequestContext::getMain();
 490                         // Commit and close any current session
 491                         session_write_close(); // persist
 492                         session_id( '' ); // detach
 493                         $_SESSION = array(); // clear in-memory array
 494                         // Remove any user IP or agent information
 495                         $context->setRequest( new FauxRequest() );
 496                         $wgRequest = $context->getRequest(); // b/c
 497                         // Now that all private information is detached from the user, it should
 498                         // be safe to load the new user. If errors occur or an exception is thrown
 499                         // and caught (leaving the main context in a mixed state), there is no risk
 500                         // of the User object being attached to the wrong IP, headers, or session.
 501                         $context->setUser( $user );
 502                         $wgUser = $context->getUser(); // b/c
 503                         if ( strlen( $params['sessionId'] ) ) { // don't make a new random ID
 504                                 wfSetupSession( $params['sessionId'] ); // sets $_SESSION
 505                         }
 506                         $request = new FauxRequest( array(), false, $_SESSION );
 507                         $request->setIP( $params['ip'] );
 508                         foreach ( $params['headers'] as $name => $value ) {
 509                                 $request->setHeader( $name, $value );
 510                         }
 511                         // Set the current context to use the new WebRequest
 512                         $context->setRequest( $request );
 513                         $wgRequest = $context->getRequest(); // b/c
 514                 };
 515
 516                 // Stash the old session and load in the new one
 517                 $oUser = self::getMain()->getUser();
 518                 $oParams = self::getMain()->exportSession();
 519                 $importSessionFunction( $user, $params );
 520
 521                 // Set callback to save and close the new session and reload the old one
 522                 return new ScopedCallback( function () use ( $importSessionFunction, $oUser, $oParams ) {
 523                         $importSessionFunction( $oUser, $oParams );
 524                 } );
 525         }
 526
 527         /**
 528          * Create a new extraneous context. The context is filled with information
 529          * external to the current session.
 530          * - Title is specified by argument
 531          * - Request is a FauxRequest, or a FauxRequest can be specified by argument
 532          * - User is an anonymous user, for separation IPv4 localhost is used
 533          * - Language will be based on the anonymous user and request, may be content
 534          *   language or a uselang param in the fauxrequest data may change the lang
 535          * - Skin will be based on the anonymous user, should be the wiki's default skin
 536          *
 537          * @param Title $title Title to use for the extraneous request
 538          * @param WebRequest|array $request A WebRequest or data to use for a FauxRequest
 539          * @return RequestContext
 540          */
 541         public static function newExtraneousContext( Title $title, $request = array() ) {
 542                 $context = new self;
 543                 $context->setTitle( $title );
 544                 if ( $request instanceof WebRequest ) {
 545                         $context->setRequest( $request );
 546                 } else {
 547                         $context->setRequest( new FauxRequest( $request ) );
 548                 }
 549                 $context->user = User::newFromName( '127.0.0.1', false );
 550
 551                 return $context;
 552         }
 553 }