includes/context/RequestContext.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @since 1.18
  19  *
  20  * @author Alexandre Emsenhuber
  21  * @author Daniel Friesen
  22  * @file
  23  */
  24
  25 /**
  26  * Group all the pieces relevant to the context of a request into one instance
  27  */
  28 class RequestContext implements IContextSource, MutableContext {
  29         /**
  30          * @var WebRequest
  31          */
  32         private $request;
  33
  34         /**
  35          * @var Title
  36          */
  37         private $title;
  38
  39         /**
  40          * @var WikiPage
  41          */
  42         private $wikipage;
  43
  44         /**
  45          * @var OutputPage
  46          */
  47         private $output;
  48
  49         /**
  50          * @var User
  51          */
  52         private $user;
  53
  54         /**
  55          * @var Language
  56          */
  57         private $lang;
  58
  59         /**
  60          * @var Skin
  61          */
  62         private $skin;
  63
  64         /**
  65          * @var \Liuggio\StatsdClient\Factory\StatsdDataFactory
  66          */
  67         private $stats;
  68
  69         /**
  70          * @var Timing
  71          */
  72         private $timing;
  73
  74         /**
  75          * @var Config
  76          */
  77         private $config;
  78
  79         /**
  80          * @var RequestContext
  81          */
  82         private static $instance = null;
  83
  84         /**
  85          * Set the Config object
  86          *
  87          * @param Config $c
  88          */
  89         public function setConfig( Config $c ) {
  90                 $this->config = $c;
  91         }
  92
  93         /**
  94          * Get the Config object
  95          *
  96          * @return Config
  97          */
  98         public function getConfig() {
  99                 if ( $this->config === null ) {
 100                         // @todo In the future, we could move this to WebStart.php so
 101                         // the Config object is ready for when initialization happens
 102                         $this->config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 103                 }
 104
 105                 return $this->config;
 106         }
 107
 108         /**
 109          * Set the WebRequest object
 110          *
 111          * @param WebRequest $r
 112          */
 113         public function setRequest( WebRequest $r ) {
 114                 $this->request = $r;
 115         }
 116
 117         /**
 118          * Get the WebRequest object
 119          *
 120          * @return WebRequest
 121          */
 122         public function getRequest() {
 123                 if ( $this->request === null ) {
 124                         global $wgRequest; # fallback to $wg till we can improve this
 125                         $this->request = $wgRequest;
 126                 }
 127
 128                 return $this->request;
 129         }
 130
 131         /**
 132          * Get the Stats object
 133          *
 134          * @return BufferingStatsdDataFactory
 135          */
 136         public function getStats() {
 137                 if ( $this->stats === null ) {
 138                         $config = $this->getConfig();
 139                         $prefix = $config->get( 'StatsdMetricPrefix' )
 140                                 ? rtrim( $config->get( 'StatsdMetricPrefix' ), '.' )
 141                                 : 'MediaWiki';
 142                         $this->stats = new BufferingStatsdDataFactory( $prefix );
 143                 }
 144                 return $this->stats;
 145         }
 146
 147         /**
 148          * Get the timing object
 149          *
 150          * @return Timing
 151          */
 152         public function getTiming() {
 153                 if ( $this->timing === null ) {
 154                         $this->timing = new Timing();
 155                 }
 156                 return $this->timing;
 157         }
 158
 159         /**
 160          * Set the Title object
 161          *
 162          * @param Title $title
 163          */
 164         public function setTitle( Title $title ) {
 165                 $this->title = $title;
 166                 // Erase the WikiPage so a new one with the new title gets created.
 167                 $this->wikipage = null;
 168         }
 169
 170         /**
 171          * Get the Title object
 172          *
 173          * @return Title|null
 174          */
 175         public function getTitle() {
 176                 if ( $this->title === null ) {
 177                         global $wgTitle; # fallback to $wg till we can improve this
 178                         $this->title = $wgTitle;
 179                         wfDebugLog(
 180                                 'GlobalTitleFail',
 181                                 __METHOD__ . ' called by ' . wfGetAllCallers( 5 ) . ' with no title set.'
 182                         );
 183                 }
 184
 185                 return $this->title;
 186         }
 187
 188         /**
 189          * Check, if a Title object is set
 190          *
 191          * @since 1.25
 192          * @return bool
 193          */
 194         public function hasTitle() {
 195                 return $this->title !== null;
 196         }
 197
 198         /**
 199          * Check whether a WikiPage object can be get with getWikiPage().
 200          * Callers should expect that an exception is thrown from getWikiPage()
 201          * if this method returns false.
 202          *
 203          * @since 1.19
 204          * @return bool
 205          */
 206         public function canUseWikiPage() {
 207                 if ( $this->wikipage ) {
 208                         // If there's a WikiPage object set, we can for sure get it
 209                         return true;
 210                 }
 211                 // Only pages with legitimate titles can have WikiPages.
 212                 // That usually means pages in non-virtual namespaces.
 213                 $title = $this->getTitle();
 214                 return $title ? $title->canExist() : false;
 215         }
 216
 217         /**
 218          * Set the WikiPage object
 219          *
 220          * @since 1.19
 221          * @param WikiPage $p
 222          */
 223         public function setWikiPage( WikiPage $p ) {
 224                 $pageTitle = $p->getTitle();
 225                 if ( !$this->hasTitle() || !$pageTitle->equals( $this->getTitle() ) ) {
 226                         $this->setTitle( $pageTitle );
 227                 }
 228                 // Defer this to the end since setTitle sets it to null.
 229                 $this->wikipage = $p;
 230         }
 231
 232         /**
 233          * Get the WikiPage object.
 234          * May throw an exception if there's no Title object set or the Title object
 235          * belongs to a special namespace that doesn't have WikiPage, so use first
 236          * canUseWikiPage() to check whether this method can be called safely.
 237          *
 238          * @since 1.19
 239          * @throws MWException
 240          * @return WikiPage
 241          */
 242         public function getWikiPage() {
 243                 if ( $this->wikipage === null ) {
 244                         $title = $this->getTitle();
 245                         if ( $title === null ) {
 246                                 throw new MWException( __METHOD__ . ' called without Title object set' );
 247                         }
 248                         $this->wikipage = WikiPage::factory( $title );
 249                 }
 250
 251                 return $this->wikipage;
 252         }
 253
 254         /**
 255          * @param OutputPage $o
 256          */
 257         public function setOutput( OutputPage $o ) {
 258                 $this->output = $o;
 259         }
 260
 261         /**
 262          * Get the OutputPage object
 263          *
 264          * @return OutputPage
 265          */
 266         public function getOutput() {
 267                 if ( $this->output === null ) {
 268                         $this->output = new OutputPage( $this );
 269                 }
 270
 271                 return $this->output;
 272         }
 273
 274         /**
 275          * Set the User object
 276          *
 277          * @param User $u
 278          */
 279         public function setUser( User $u ) {
 280                 $this->user = $u;
 281         }
 282
 283         /**
 284          * Get the User object
 285          *
 286          * @return User
 287          */
 288         public function getUser() {
 289                 if ( $this->user === null ) {
 290                         $this->user = User::newFromSession( $this->getRequest() );
 291                 }
 292
 293                 return $this->user;
 294         }
 295
 296         /**
 297          * Accepts a language code and ensures it's sane. Outputs a cleaned up language
 298          * code and replaces with $wgLanguageCode if not sane.
 299          * @param string $code Language code
 300          * @return string
 301          */
 302         public static function sanitizeLangCode( $code ) {
 303                 global $wgLanguageCode;
 304
 305                 // BCP 47 - letter case MUST NOT carry meaning
 306                 $code = strtolower( $code );
 307
 308                 # Validate $code
 309                 if ( !$code || !Language::isValidCode( $code ) || $code === 'qqq' ) {
 310                         wfDebug( "Invalid user language code\n" );
 311                         $code = $wgLanguageCode;
 312                 }
 313
 314                 return $code;
 315         }
 316
 317         /**
 318          * Set the Language object
 319          *
 320          * @param Language|string $l Language instance or language code
 321          * @throws MWException
 322          * @since 1.19
 323          */
 324         public function setLanguage( $l ) {
 325                 if ( $l instanceof Language ) {
 326                         $this->lang = $l;
 327                 } elseif ( is_string( $l ) ) {
 328                         $l = self::sanitizeLangCode( $l );
 329                         $obj = Language::factory( $l );
 330                         $this->lang = $obj;
 331                 } else {
 332                         throw new MWException( __METHOD__ . " was passed an invalid type of data." );
 333                 }
 334         }
 335
 336         /**
 337          * Get the Language object.
 338          * Initialization of user or request objects can depend on this.
 339          * @return Language
 340          * @throws Exception
 341          * @since 1.19
 342          */
 343         public function getLanguage() {
 344                 if ( isset( $this->recursion ) ) {
 345                         trigger_error( "Recursion detected in " . __METHOD__, E_USER_WARNING );
 346                         $e = new Exception;
 347                         wfDebugLog( 'recursion-guard', "Recursion detected:\n" . $e->getTraceAsString() );
 348
 349                         $code = $this->getConfig()->get( 'LanguageCode' ) ?: 'en';
 350                         $this->lang = Language::factory( $code );
 351                 } elseif ( $this->lang === null ) {
 352                         $this->recursion = true;
 353
 354                         global $wgContLang;
 355
 356                         try {
 357                                 $request = $this->getRequest();
 358                                 $user = $this->getUser();
 359
 360                                 $code = $request->getVal( 'uselang', 'user' );
 361                                 if ( $code === 'user' ) {
 362                                         $code = $user->getOption( 'language' );
 363                                 }
 364                                 $code = self::sanitizeLangCode( $code );
 365
 366                                 Hooks::run( 'UserGetLanguageObject', array( $user, &$code, $this ) );
 367
 368                                 if ( $code === $this->getConfig()->get( 'LanguageCode' ) ) {
 369                                         $this->lang = $wgContLang;
 370                                 } else {
 371                                         $obj = Language::factory( $code );
 372                                         $this->lang = $obj;
 373                                 }
 374
 375                                 unset( $this->recursion );
 376                         }
 377                         catch ( Exception $ex ) {
 378                                 unset( $this->recursion );
 379                                 throw $ex;
 380                         }
 381                 }
 382
 383                 return $this->lang;
 384         }
 385
 386         /**
 387          * Set the Skin object
 388          *
 389          * @param Skin $s
 390          */
 391         public function setSkin( Skin $s ) {
 392                 $this->skin = clone $s;
 393                 $this->skin->setContext( $this );
 394         }
 395
 396         /**
 397          * Get the Skin object
 398          *
 399          * @return Skin
 400          */
 401         public function getSkin() {
 402                 if ( $this->skin === null ) {
 403                         $skin = null;
 404                         Hooks::run( 'RequestContextCreateSkin', array( $this, &$skin ) );
 405                         $factory = SkinFactory::getDefaultInstance();
 406
 407                         // If the hook worked try to set a skin from it
 408                         if ( $skin instanceof Skin ) {
 409                                 $this->skin = $skin;
 410                         } elseif ( is_string( $skin ) ) {
 411                                 // Normalize the key, just in case the hook did something weird.
 412                                 $normalized = Skin::normalizeKey( $skin );
 413                                 $this->skin = $factory->makeSkin( $normalized );
 414                         }
 415
 416                         // If this is still null (the hook didn't run or didn't work)
 417                         // then go through the normal processing to load a skin
 418                         if ( $this->skin === null ) {
 419                                 if ( !in_array( 'skin', $this->getConfig()->get( 'HiddenPrefs' ) ) ) {
 420                                         # get the user skin
 421                                         $userSkin = $this->getUser()->getOption( 'skin' );
 422                                         $userSkin = $this->getRequest()->getVal( 'useskin', $userSkin );
 423                                 } else {
 424                                         # if we're not allowing users to override, then use the default
 425                                         $userSkin = $this->getConfig()->get( 'DefaultSkin' );
 426                                 }
 427
 428                                 // Normalize the key in case the user is passing gibberish
 429                                 // or has old preferences (bug 69566).
 430                                 $normalized = Skin::normalizeKey( $userSkin );
 431
 432                                 // Skin::normalizeKey will also validate it, so
 433                                 // this won't throw an exception
 434                                 $this->skin = $factory->makeSkin( $normalized );
 435                         }
 436
 437                         // After all that set a context on whatever skin got created
 438                         $this->skin->setContext( $this );
 439                 }
 440
 441                 return $this->skin;
 442         }
 443
 444         /** Helpful methods **/
 445
 446         /**
 447          * Get a Message object with context set
 448          * Parameters are the same as wfMessage()
 449          *
 450          * @param mixed ...
 451          * @return Message
 452          */
 453         public function msg() {
 454                 $args = func_get_args();
 455
 456                 return call_user_func_array( 'wfMessage', $args )->setContext( $this );
 457         }
 458
 459         /** Static methods **/
 460
 461         /**
 462          * Get the RequestContext object associated with the main request
 463          *
 464          * @return RequestContext
 465          */
 466         public static function getMain() {
 467                 if ( self::$instance === null ) {
 468                         self::$instance = new self;
 469                 }
 470
 471                 return self::$instance;
 472         }
 473
 474         /**
 475          * Get the RequestContext object associated with the main request
 476          * and gives a warning to the log, to find places, where a context maybe is missing.
 477          *
 478          * @param string $func
 479          * @return RequestContext
 480          * @since 1.24
 481          */
 482         public static function getMainAndWarn( $func = __METHOD__ ) {
 483                 wfDebug( $func . ' called without context. ' .
 484                         "Using RequestContext::getMain() for sanity\n" );
 485
 486                 return self::getMain();
 487         }
 488
 489         /**
 490          * Resets singleton returned by getMain(). Should be called only from unit tests.
 491          */
 492         public static function resetMain() {
 493                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
 494                         throw new MWException( __METHOD__ . '() should be called only from unit tests!' );
 495                 }
 496                 self::$instance = null;
 497         }
 498
 499         /**
 500          * Export the resolved user IP, HTTP headers, user ID, and session ID.
 501          * The result will be reasonably sized to allow for serialization.
 502          *
 503          * @return array
 504          * @since 1.21
 505          */
 506         public function exportSession() {
 507                 return array(
 508                         'ip' => $this->getRequest()->getIP(),
 509                         'headers' => $this->getRequest()->getAllHeaders(),
 510                         'sessionId' => session_id(),
 511                         'userId' => $this->getUser()->getId()
 512                 );
 513         }
 514
 515         /**
 516          * Import an client IP address, HTTP headers, user ID, and session ID
 517          *
 518          * This sets the current session, $wgUser, and $wgRequest from $params.
 519          * Once the return value falls out of scope, the old context is restored.
 520          * This method should only be called in contexts where there is no session
 521          * ID or end user receiving the response (CLI or HTTP job runners). This
 522          * is partly enforced, and is done so to avoid leaking cookies if certain
 523          * error conditions arise.
 524          *
 525          * This is useful when background scripts inherit context when acting on
 526          * behalf of a user. In general the 'sessionId' parameter should be set
 527          * to an empty string unless session importing is *truly* needed. This
 528          * feature is somewhat deprecated.
 529          *
 530          * @note suhosin.session.encrypt may interfere with this method.
 531          *
 532          * @param array $params Result of RequestContext::exportSession()
 533          * @return ScopedCallback
 534          * @throws MWException
 535          * @since 1.21
 536          */
 537         public static function importScopedSession( array $params ) {
 538                 if ( session_id() != '' && strlen( $params['sessionId'] ) ) {
 539                         // Sanity check to avoid sending random cookies for the wrong users.
 540                         // This method should only called by CLI scripts or by HTTP job runners.
 541                         throw new MWException( "Sessions can only be imported when none is active." );
 542                 } elseif ( !IP::isValid( $params['ip'] ) ) {
 543                         throw new MWException( "Invalid client IP address '{$params['ip']}'." );
 544                 }
 545
 546                 if ( $params['userId'] ) { // logged-in user
 547                         $user = User::newFromId( $params['userId'] );
 548                         $user->load();
 549                         if ( !$user->getId() ) {
 550                                 throw new MWException( "No user with ID '{$params['userId']}'." );
 551                         }
 552                 } else { // anon user
 553                         $user = User::newFromName( $params['ip'], false );
 554                 }
 555
 556                 $importSessionFunc = function ( User $user, array $params ) {
 557                         global $wgRequest, $wgUser;
 558
 559                         $context = RequestContext::getMain();
 560                         // Commit and close any current session
 561                         session_write_close(); // persist
 562                         session_id( '' ); // detach
 563                         $_SESSION = array(); // clear in-memory array
 564                         // Remove any user IP or agent information
 565                         $context->setRequest( new FauxRequest() );
 566                         $wgRequest = $context->getRequest(); // b/c
 567                         // Now that all private information is detached from the user, it should
 568                         // be safe to load the new user. If errors occur or an exception is thrown
 569                         // and caught (leaving the main context in a mixed state), there is no risk
 570                         // of the User object being attached to the wrong IP, headers, or session.
 571                         $context->setUser( $user );
 572                         $wgUser = $context->getUser(); // b/c
 573                         if ( strlen( $params['sessionId'] ) ) { // don't make a new random ID
 574                                 wfSetupSession( $params['sessionId'] ); // sets $_SESSION
 575                         }
 576                         $request = new FauxRequest( array(), false, $_SESSION );
 577                         $request->setIP( $params['ip'] );
 578                         foreach ( $params['headers'] as $name => $value ) {
 579                                 $request->setHeader( $name, $value );
 580                         }
 581                         // Set the current context to use the new WebRequest
 582                         $context->setRequest( $request );
 583                         $wgRequest = $context->getRequest(); // b/c
 584                 };
 585
 586                 // Stash the old session and load in the new one
 587                 $oUser = self::getMain()->getUser();
 588                 $oParams = self::getMain()->exportSession();
 589                 $oRequest = self::getMain()->getRequest();
 590                 $importSessionFunc( $user, $params );
 591
 592                 // Set callback to save and close the new session and reload the old one
 593                 return new ScopedCallback(
 594                         function () use ( $importSessionFunc, $oUser, $oParams, $oRequest ) {
 595                                 global $wgRequest;
 596                                 $importSessionFunc( $oUser, $oParams );
 597                                 // Restore the exact previous Request object (instead of leaving FauxRequest)
 598                                 RequestContext::getMain()->setRequest( $oRequest );
 599                                 $wgRequest = RequestContext::getMain()->getRequest(); // b/c
 600                         }
 601                 );
 602         }
 603
 604         /**
 605          * Create a new extraneous context. The context is filled with information
 606          * external to the current session.
 607          * - Title is specified by argument
 608          * - Request is a FauxRequest, or a FauxRequest can be specified by argument
 609          * - User is an anonymous user, for separation IPv4 localhost is used
 610          * - Language will be based on the anonymous user and request, may be content
 611          *   language or a uselang param in the fauxrequest data may change the lang
 612          * - Skin will be based on the anonymous user, should be the wiki's default skin
 613          *
 614          * @param Title $title Title to use for the extraneous request
 615          * @param WebRequest|array $request A WebRequest or data to use for a FauxRequest
 616          * @return RequestContext
 617          */
 618         public static function newExtraneousContext( Title $title, $request = array() ) {
 619                 $context = new self;
 620                 $context->setTitle( $title );
 621                 if ( $request instanceof WebRequest ) {
 622                         $context->setRequest( $request );
 623                 } else {
 624                         $context->setRequest( new FauxRequest( $request ) );
 625                 }
 626                 $context->user = User::newFromName( '127.0.0.1', false );
 627
 628                 return $context;
 629         }
 630 }