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 $title
 127          */
 128         public function setTitle( Title $title ) {
 129                 $this->title = $title;
 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                         wfDebugLog( 'GlobalTitleFail', __METHOD__ . ' called by ' . wfGetCaller() . ' with no title set.' );
 144                 }
 145
 146                 return $this->title;
 147         }
 148
 149         /**
 150          * Check whether a WikiPage object can be get with getWikiPage().
 151          * Callers should expect that an exception is thrown from getWikiPage()
 152          * if this method returns false.
 153          *
 154          * @since 1.19
 155          * @return bool
 156          */
 157         public function canUseWikiPage() {
 158                 if ( $this->wikipage ) {
 159                         // If there's a WikiPage object set, we can for sure get it
 160                         return true;
 161                 }
 162                 // Only pages with legitimate titles can have WikiPages.
 163                 // That usually means pages in non-virtual namespaces.
 164                 $title = $this->getTitle();
 165                 return $title ? $title->canExist() : false;
 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 $code
 261                 if ( !$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          * @param Language|string $l Language instance or language code
 273          * @throws MWException
 274          * @since 1.19
 275          */
 276         public function setLanguage( $l ) {
 277                 if ( $l instanceof Language ) {
 278                         $this->lang = $l;
 279                 } elseif ( is_string( $l ) ) {
 280                         $l = self::sanitizeLangCode( $l );
 281                         $obj = Language::factory( $l );
 282                         $this->lang = $obj;
 283                 } else {
 284                         throw new MWException( __METHOD__ . " was passed an invalid type of data." );
 285                 }
 286         }
 287
 288         /**
 289          * Get the Language object.
 290          * Initialization of user or request objects can depend on this.
 291          *
 292          * @return Language
 293          * @since 1.19
 294          */
 295         public function getLanguage() {
 296                 if ( isset( $this->recursion ) ) {
 297                         trigger_error( "Recursion detected in " . __METHOD__, E_USER_WARNING );
 298                         $e = new Exception;
 299                         wfDebugLog( 'recursion-guard', "Recursion detected:\n" . $e->getTraceAsString() );
 300
 301                         $code = $this->getConfig()->get( 'LanguageCode' ) ?: 'en';
 302                         $this->lang = Language::factory( $code );
 303                 } elseif ( $this->lang === null ) {
 304                         $this->recursion = true;
 305
 306                         global $wgContLang;
 307
 308                         try {
 309                                 $request = $this->getRequest();
 310                                 $user = $this->getUser();
 311
 312                                 $code = $request->getVal( 'uselang', $user->getOption( 'language' ) );
 313                                 $code = self::sanitizeLangCode( $code );
 314
 315                                 wfRunHooks( 'UserGetLanguageObject', array( $user, &$code, $this ) );
 316
 317                                 if ( $code === $this->getConfig()->get( 'LanguageCode' ) ) {
 318                                         $this->lang = $wgContLang;
 319                                 } else {
 320                                         $obj = Language::factory( $code );
 321                                         $this->lang = $obj;
 322                                 }
 323
 324                                 unset( $this->recursion );
 325                         }
 326                         catch ( Exception $ex ) {
 327                                 unset( $this->recursion );
 328                                 throw $ex;
 329                         }
 330                 }
 331
 332                 return $this->lang;
 333         }
 334
 335         /**
 336          * Set the Skin object
 337          *
 338          * @param Skin $s
 339          */
 340         public function setSkin( Skin $s ) {
 341                 $this->skin = clone $s;
 342                 $this->skin->setContext( $this );
 343         }
 344
 345         /**
 346          * Get the Skin object
 347          *
 348          * @return Skin
 349          */
 350         public function getSkin() {
 351                 if ( $this->skin === null ) {
 352                         wfProfileIn( __METHOD__ . '-createskin' );
 353
 354                         $skin = null;
 355                         wfRunHooks( 'RequestContextCreateSkin', array( $this, &$skin ) );
 356                         $factory = SkinFactory::getDefaultInstance();
 357
 358                         // If the hook worked try to set a skin from it
 359                         if ( $skin instanceof Skin ) {
 360                                 $this->skin = $skin;
 361                         } elseif ( is_string( $skin ) ) {
 362                                 // Normalize the key, just in case the hook did something weird.
 363                                 $normalized = Skin::normalizeKey( $skin );
 364                                 $this->skin = $factory->makeSkin( $normalized );
 365                         }
 366
 367                         // If this is still null (the hook didn't run or didn't work)
 368                         // then go through the normal processing to load a skin
 369                         if ( $this->skin === null ) {
 370                                 if ( !in_array( 'skin', $this->getConfig()->get( 'HiddenPrefs' ) ) ) {
 371                                         # get the user skin
 372                                         $userSkin = $this->getUser()->getOption( 'skin' );
 373                                         $userSkin = $this->getRequest()->getVal( 'useskin', $userSkin );
 374                                 } else {
 375                                         # if we're not allowing users to override, then use the default
 376                                         $userSkin = $this->getConfig()->get( 'DefaultSkin' );
 377                                 }
 378
 379                                 // Normalize the key in case the user is passing gibberish
 380                                 // or has old preferences (bug 69566).
 381                                 $normalized = Skin::normalizeKey( $userSkin );
 382
 383                                 // Skin::normalizeKey will also validate it, so
 384                                 // this won't throw an exception
 385                                 $this->skin = $factory->makeSkin( $normalized );
 386                         }
 387
 388                         // After all that set a context on whatever skin got created
 389                         $this->skin->setContext( $this );
 390                         wfProfileOut( __METHOD__ . '-createskin' );
 391                 }
 392
 393                 return $this->skin;
 394         }
 395
 396         /** Helpful methods **/
 397
 398         /**
 399          * Get a Message object with context set
 400          * Parameters are the same as wfMessage()
 401          *
 402          * @return Message
 403          */
 404         public function msg() {
 405                 $args = func_get_args();
 406
 407                 return call_user_func_array( 'wfMessage', $args )->setContext( $this );
 408         }
 409
 410         /** Static methods **/
 411
 412         /**
 413          * Get the RequestContext object associated with the main request
 414          *
 415          * @return RequestContext
 416          */
 417         public static function getMain() {
 418                 if ( self::$instance === null ) {
 419                         self::$instance = new self;
 420                 }
 421
 422                 return self::$instance;
 423         }
 424
 425         /**
 426          * Get the RequestContext object associated with the main request
 427          * and gives a warning to the log, to find places, where a context maybe is missing.
 428          *
 429          * @param string $func
 430          * @return RequestContext
 431          * @since 1.24
 432          */
 433         public static function getMainAndWarn( $func = __METHOD__ ) {
 434                 wfDebug( $func . ' called without context. ' .
 435                         "Using RequestContext::getMain() for sanity\n" );
 436
 437                 return self::getMain();
 438         }
 439
 440         /**
 441          * Resets singleton returned by getMain(). Should be called only from unit tests.
 442          */
 443         public static function resetMain() {
 444                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
 445                         throw new MWException( __METHOD__ . '() should be called only from unit tests!' );
 446                 }
 447                 self::$instance = null;
 448         }
 449
 450         /**
 451          * Export the resolved user IP, HTTP headers, user ID, and session ID.
 452          * The result will be reasonably sized to allow for serialization.
 453          *
 454          * @return array
 455          * @since 1.21
 456          */
 457         public function exportSession() {
 458                 return array(
 459                         'ip' => $this->getRequest()->getIP(),
 460                         'headers' => $this->getRequest()->getAllHeaders(),
 461                         'sessionId' => session_id(),
 462                         'userId' => $this->getUser()->getId()
 463                 );
 464         }
 465
 466         /**
 467          * Import the resolved user IP, HTTP headers, user ID, and session ID.
 468          * This sets the current session and sets $wgUser and $wgRequest.
 469          * Once the return value falls out of scope, the old context is restored.
 470          * This function can only be called within CLI mode scripts.
 471          *
 472          * This will setup the session from the given ID. This is useful when
 473          * background scripts inherit context when acting on behalf of a user.
 474          *
 475          * @note suhosin.session.encrypt may interfere with this method.
 476          *
 477          * @param array $params Result of RequestContext::exportSession()
 478          * @return ScopedCallback
 479          * @throws MWException
 480          * @since 1.21
 481          */
 482         public static function importScopedSession( array $params ) {
 483                 if ( PHP_SAPI !== 'cli' ) {
 484                         // Don't send random private cookies or turn $wgRequest into FauxRequest
 485                         throw new MWException( "Sessions can only be imported in cli mode." );
 486                 } elseif ( !strlen( $params['sessionId'] ) ) {
 487                         throw new MWException( "No session ID was specified." );
 488                 }
 489
 490                 if ( $params['userId'] ) { // logged-in user
 491                         $user = User::newFromId( $params['userId'] );
 492                         $user->load();
 493                         if ( !$user->getId() ) {
 494                                 throw new MWException( "No user with ID '{$params['userId']}'." );
 495                         }
 496                 } elseif ( !IP::isValid( $params['ip'] ) ) {
 497                         throw new MWException( "Could not load user '{$params['ip']}'." );
 498                 } else { // anon user
 499                         $user = User::newFromName( $params['ip'], false );
 500                 }
 501
 502                 $importSessionFunction = function ( User $user, array $params ) {
 503                         global $wgRequest, $wgUser;
 504
 505                         $context = RequestContext::getMain();
 506                         // Commit and close any current session
 507                         session_write_close(); // persist
 508                         session_id( '' ); // detach
 509                         $_SESSION = array(); // clear in-memory array
 510                         // Remove any user IP or agent information
 511                         $context->setRequest( new FauxRequest() );
 512                         $wgRequest = $context->getRequest(); // b/c
 513                         // Now that all private information is detached from the user, it should
 514                         // be safe to load the new user. If errors occur or an exception is thrown
 515                         // and caught (leaving the main context in a mixed state), there is no risk
 516                         // of the User object being attached to the wrong IP, headers, or session.
 517                         $context->setUser( $user );
 518                         $wgUser = $context->getUser(); // b/c
 519                         if ( strlen( $params['sessionId'] ) ) { // don't make a new random ID
 520                                 wfSetupSession( $params['sessionId'] ); // sets $_SESSION
 521                         }
 522                         $request = new FauxRequest( array(), false, $_SESSION );
 523                         $request->setIP( $params['ip'] );
 524                         foreach ( $params['headers'] as $name => $value ) {
 525                                 $request->setHeader( $name, $value );
 526                         }
 527                         // Set the current context to use the new WebRequest
 528                         $context->setRequest( $request );
 529                         $wgRequest = $context->getRequest(); // b/c
 530                 };
 531
 532                 // Stash the old session and load in the new one
 533                 $oUser = self::getMain()->getUser();
 534                 $oParams = self::getMain()->exportSession();
 535                 $importSessionFunction( $user, $params );
 536
 537                 // Set callback to save and close the new session and reload the old one
 538                 return new ScopedCallback( function () use ( $importSessionFunction, $oUser, $oParams ) {
 539                         $importSessionFunction( $oUser, $oParams );
 540                 } );
 541         }
 542
 543         /**
 544          * Create a new extraneous context. The context is filled with information
 545          * external to the current session.
 546          * - Title is specified by argument
 547          * - Request is a FauxRequest, or a FauxRequest can be specified by argument
 548          * - User is an anonymous user, for separation IPv4 localhost is used
 549          * - Language will be based on the anonymous user and request, may be content
 550          *   language or a uselang param in the fauxrequest data may change the lang
 551          * - Skin will be based on the anonymous user, should be the wiki's default skin
 552          *
 553          * @param Title $title Title to use for the extraneous request
 554          * @param WebRequest|array $request A WebRequest or data to use for a FauxRequest
 555          * @return RequestContext
 556          */
 557         public static function newExtraneousContext( Title $title, $request = array() ) {
 558                 $context = new self;
 559                 $context->setTitle( $title );
 560                 if ( $request instanceof WebRequest ) {
 561                         $context->setRequest( $request );
 562                 } else {
 563                         $context->setRequest( new FauxRequest( $request ) );
 564                 }
 565                 $context->user = User::newFromName( '127.0.0.1', false );
 566
 567                 return $context;
 568         }
 569 }