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