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 $wgCommandLineMode;
 125                         // create the WebRequest object on the fly
 126                         if ( $wgCommandLineMode ) {
 127                                 $this->request = new FauxRequest( array() );
 128                         } else {
 129                                 $this->request = new WebRequest();
 130                         }
 131                 }
 132
 133                 return $this->request;
 134         }
 135
 136         /**
 137          * Get the Stats object
 138          *
 139          * @return BufferingStatsdDataFactory
 140          */
 141         public function getStats() {
 142                 if ( $this->stats === null ) {
 143                         $config = $this->getConfig();
 144                         $prefix = $config->get( 'StatsdMetricPrefix' )
 145                                 ? rtrim( $config->get( 'StatsdMetricPrefix' ), '.' )
 146                                 : 'MediaWiki';
 147                         $this->stats = new BufferingStatsdDataFactory( $prefix );
 148                 }
 149                 return $this->stats;
 150         }
 151
 152         /**
 153          * Get the timing object
 154          *
 155          * @return Timing
 156          */
 157         public function getTiming() {
 158                 if ( $this->timing === null ) {
 159                         $this->timing = new Timing();
 160                 }
 161                 return $this->timing;
 162         }
 163
 164         /**
 165          * Set the Title object
 166          *
 167          * @param Title $title
 168          */
 169         public function setTitle( Title $title ) {
 170                 $this->title = $title;
 171                 // Erase the WikiPage so a new one with the new title gets created.
 172                 $this->wikipage = null;
 173         }
 174
 175         /**
 176          * Get the Title object
 177          *
 178          * @return Title|null
 179          */
 180         public function getTitle() {
 181                 if ( $this->title === null ) {
 182                         global $wgTitle; # fallback to $wg till we can improve this
 183                         $this->title = $wgTitle;
 184                         wfDebugLog(
 185                                 'GlobalTitleFail',
 186                                 __METHOD__ . ' called by ' . wfGetAllCallers( 5 ) . ' with no title set.'
 187                         );
 188                 }
 189
 190                 return $this->title;
 191         }
 192
 193         /**
 194          * Check, if a Title object is set
 195          *
 196          * @since 1.25
 197          * @return bool
 198          */
 199         public function hasTitle() {
 200                 return $this->title !== null;
 201         }
 202
 203         /**
 204          * Check whether a WikiPage object can be get with getWikiPage().
 205          * Callers should expect that an exception is thrown from getWikiPage()
 206          * if this method returns false.
 207          *
 208          * @since 1.19
 209          * @return bool
 210          */
 211         public function canUseWikiPage() {
 212                 if ( $this->wikipage ) {
 213                         // If there's a WikiPage object set, we can for sure get it
 214                         return true;
 215                 }
 216                 // Only pages with legitimate titles can have WikiPages.
 217                 // That usually means pages in non-virtual namespaces.
 218                 $title = $this->getTitle();
 219                 return $title ? $title->canExist() : false;
 220         }
 221
 222         /**
 223          * Set the WikiPage object
 224          *
 225          * @since 1.19
 226          * @param WikiPage $p
 227          */
 228         public function setWikiPage( WikiPage $p ) {
 229                 $pageTitle = $p->getTitle();
 230                 if ( !$this->hasTitle() || !$pageTitle->equals( $this->getTitle() ) ) {
 231                         $this->setTitle( $pageTitle );
 232                 }
 233                 // Defer this to the end since setTitle sets it to null.
 234                 $this->wikipage = $p;
 235         }
 236
 237         /**
 238          * Get the WikiPage object.
 239          * May throw an exception if there's no Title object set or the Title object
 240          * belongs to a special namespace that doesn't have WikiPage, so use first
 241          * canUseWikiPage() to check whether this method can be called safely.
 242          *
 243          * @since 1.19
 244          * @throws MWException
 245          * @return WikiPage
 246          */
 247         public function getWikiPage() {
 248                 if ( $this->wikipage === null ) {
 249                         $title = $this->getTitle();
 250                         if ( $title === null ) {
 251                                 throw new MWException( __METHOD__ . ' called without Title object set' );
 252                         }
 253                         $this->wikipage = WikiPage::factory( $title );
 254                 }
 255
 256                 return $this->wikipage;
 257         }
 258
 259         /**
 260          * @param OutputPage $o
 261          */
 262         public function setOutput( OutputPage $o ) {
 263                 $this->output = $o;
 264         }
 265
 266         /**
 267          * Get the OutputPage object
 268          *
 269          * @return OutputPage
 270          */
 271         public function getOutput() {
 272                 if ( $this->output === null ) {
 273                         $this->output = new OutputPage( $this );
 274                 }
 275
 276                 return $this->output;
 277         }
 278
 279         /**
 280          * Set the User object
 281          *
 282          * @param User $u
 283          */
 284         public function setUser( User $u ) {
 285                 $this->user = $u;
 286         }
 287
 288         /**
 289          * Get the User object
 290          *
 291          * @return User
 292          */
 293         public function getUser() {
 294                 if ( $this->user === null ) {
 295                         $this->user = User::newFromSession( $this->getRequest() );
 296                 }
 297
 298                 return $this->user;
 299         }
 300
 301         /**
 302          * Accepts a language code and ensures it's sane. Outputs a cleaned up language
 303          * code and replaces with $wgLanguageCode if not sane.
 304          * @param string $code Language code
 305          * @return string
 306          */
 307         public static function sanitizeLangCode( $code ) {
 308                 global $wgLanguageCode;
 309
 310                 // BCP 47 - letter case MUST NOT carry meaning
 311                 $code = strtolower( $code );
 312
 313                 # Validate $code
 314                 if ( !$code || !Language::isValidCode( $code ) || $code === 'qqq' ) {
 315                         wfDebug( "Invalid user language code\n" );
 316                         $code = $wgLanguageCode;
 317                 }
 318
 319                 return $code;
 320         }
 321
 322         /**
 323          * Set the Language object
 324          *
 325          * @param Language|string $l Language instance or language code
 326          * @throws MWException
 327          * @since 1.19
 328          */
 329         public function setLanguage( $l ) {
 330                 if ( $l instanceof Language ) {
 331                         $this->lang = $l;
 332                 } elseif ( is_string( $l ) ) {
 333                         $l = self::sanitizeLangCode( $l );
 334                         $obj = Language::factory( $l );
 335                         $this->lang = $obj;
 336                 } else {
 337                         throw new MWException( __METHOD__ . " was passed an invalid type of data." );
 338                 }
 339         }
 340
 341         /**
 342          * Get the Language object.
 343          * Initialization of user or request objects can depend on this.
 344          * @return Language
 345          * @throws Exception
 346          * @since 1.19
 347          */
 348         public function getLanguage() {
 349                 if ( isset( $this->recursion ) ) {
 350                         trigger_error( "Recursion detected in " . __METHOD__, E_USER_WARNING );
 351                         $e = new Exception;
 352                         wfDebugLog( 'recursion-guard', "Recursion detected:\n" . $e->getTraceAsString() );
 353
 354                         $code = $this->getConfig()->get( 'LanguageCode' ) ?: 'en';
 355                         $this->lang = Language::factory( $code );
 356                 } elseif ( $this->lang === null ) {
 357                         $this->recursion = true;
 358
 359                         global $wgContLang;
 360
 361                         try {
 362                                 $request = $this->getRequest();
 363                                 $user = $this->getUser();
 364
 365                                 $code = $request->getVal( 'uselang', 'user' );
 366                                 if ( $code === 'user' ) {
 367                                         $code = $user->getOption( 'language' );
 368                                 }
 369                                 $code = self::sanitizeLangCode( $code );
 370
 371                                 Hooks::run( 'UserGetLanguageObject', array( $user, &$code, $this ) );
 372
 373                                 if ( $code === $this->getConfig()->get( 'LanguageCode' ) ) {
 374                                         $this->lang = $wgContLang;
 375                                 } else {
 376                                         $obj = Language::factory( $code );
 377                                         $this->lang = $obj;
 378                                 }
 379
 380                                 unset( $this->recursion );
 381                         }
 382                         catch ( Exception $ex ) {
 383                                 unset( $this->recursion );
 384                                 throw $ex;
 385                         }
 386                 }
 387
 388                 return $this->lang;
 389         }
 390
 391         /**
 392          * Set the Skin object
 393          *
 394          * @param Skin $s
 395          */
 396         public function setSkin( Skin $s ) {
 397                 $this->skin = clone $s;
 398                 $this->skin->setContext( $this );
 399         }
 400
 401         /**
 402          * Get the Skin object
 403          *
 404          * @return Skin
 405          */
 406         public function getSkin() {
 407                 if ( $this->skin === null ) {
 408                         $skin = null;
 409                         Hooks::run( 'RequestContextCreateSkin', array( $this, &$skin ) );
 410                         $factory = SkinFactory::getDefaultInstance();
 411
 412                         // If the hook worked try to set a skin from it
 413                         if ( $skin instanceof Skin ) {
 414                                 $this->skin = $skin;
 415                         } elseif ( is_string( $skin ) ) {
 416                                 // Normalize the key, just in case the hook did something weird.
 417                                 $normalized = Skin::normalizeKey( $skin );
 418                                 $this->skin = $factory->makeSkin( $normalized );
 419                         }
 420
 421                         // If this is still null (the hook didn't run or didn't work)
 422                         // then go through the normal processing to load a skin
 423                         if ( $this->skin === null ) {
 424                                 if ( !in_array( 'skin', $this->getConfig()->get( 'HiddenPrefs' ) ) ) {
 425                                         # get the user skin
 426                                         $userSkin = $this->getUser()->getOption( 'skin' );
 427                                         $userSkin = $this->getRequest()->getVal( 'useskin', $userSkin );
 428                                 } else {
 429                                         # if we're not allowing users to override, then use the default
 430                                         $userSkin = $this->getConfig()->get( 'DefaultSkin' );
 431                                 }
 432
 433                                 // Normalize the key in case the user is passing gibberish
 434                                 // or has old preferences (bug 69566).
 435                                 $normalized = Skin::normalizeKey( $userSkin );
 436
 437                                 // Skin::normalizeKey will also validate it, so
 438                                 // this won't throw an exception
 439                                 $this->skin = $factory->makeSkin( $normalized );
 440                         }
 441
 442                         // After all that set a context on whatever skin got created
 443                         $this->skin->setContext( $this );
 444                 }
 445
 446                 return $this->skin;
 447         }
 448
 449         /** Helpful methods **/
 450
 451         /**
 452          * Get a Message object with context set
 453          * Parameters are the same as wfMessage()
 454          *
 455          * @param mixed ...
 456          * @return Message
 457          */
 458         public function msg() {
 459                 $args = func_get_args();
 460
 461                 return call_user_func_array( 'wfMessage', $args )->setContext( $this );
 462         }
 463
 464         /** Static methods **/
 465
 466         /**
 467          * Get the RequestContext object associated with the main request
 468          *
 469          * @return RequestContext
 470          */
 471         public static function getMain() {
 472                 if ( self::$instance === null ) {
 473                         self::$instance = new self;
 474                 }
 475
 476                 return self::$instance;
 477         }
 478
 479         /**
 480          * Get the RequestContext object associated with the main request
 481          * and gives a warning to the log, to find places, where a context maybe is missing.
 482          *
 483          * @param string $func
 484          * @return RequestContext
 485          * @since 1.24
 486          */
 487         public static function getMainAndWarn( $func = __METHOD__ ) {
 488                 wfDebug( $func . ' called without context. ' .
 489                         "Using RequestContext::getMain() for sanity\n" );
 490
 491                 return self::getMain();
 492         }
 493
 494         /**
 495          * Resets singleton returned by getMain(). Should be called only from unit tests.
 496          */
 497         public static function resetMain() {
 498                 if ( !defined( 'MW_PHPUNIT_TEST' ) ) {
 499                         throw new MWException( __METHOD__ . '() should be called only from unit tests!' );
 500                 }
 501                 self::$instance = null;
 502         }
 503
 504         /**
 505          * Export the resolved user IP, HTTP headers, user ID, and session ID.
 506          * The result will be reasonably sized to allow for serialization.
 507          *
 508          * @return array
 509          * @since 1.21
 510          */
 511         public function exportSession() {
 512                 return array(
 513                         'ip' => $this->getRequest()->getIP(),
 514                         'headers' => $this->getRequest()->getAllHeaders(),
 515                         'sessionId' => session_id(),
 516                         'userId' => $this->getUser()->getId()
 517                 );
 518         }
 519
 520         /**
 521          * Import an client IP address, HTTP headers, user ID, and session ID
 522          *
 523          * This sets the current session, $wgUser, and $wgRequest from $params.
 524          * Once the return value falls out of scope, the old context is restored.
 525          * This method should only be called in contexts where there is no session
 526          * ID or end user receiving the response (CLI or HTTP job runners). This
 527          * is partly enforced, and is done so to avoid leaking cookies if certain
 528          * error conditions arise.
 529          *
 530          * This is useful when background scripts inherit context when acting on
 531          * behalf of a user. In general the 'sessionId' parameter should be set
 532          * to an empty string unless session importing is *truly* needed. This
 533          * feature is somewhat deprecated.
 534          *
 535          * @note suhosin.session.encrypt may interfere with this method.
 536          *
 537          * @param array $params Result of RequestContext::exportSession()
 538          * @return ScopedCallback
 539          * @throws MWException
 540          * @since 1.21
 541          */
 542         public static function importScopedSession( array $params ) {
 543                 if ( session_id() != '' && strlen( $params['sessionId'] ) ) {
 544                         // Sanity check to avoid sending random cookies for the wrong users.
 545                         // This method should only called by CLI scripts or by HTTP job runners.
 546                         throw new MWException( "Sessions can only be imported when none is active." );
 547                 } elseif ( !IP::isValid( $params['ip'] ) ) {
 548                         throw new MWException( "Invalid client IP address '{$params['ip']}'." );
 549                 }
 550
 551                 if ( $params['userId'] ) { // logged-in user
 552                         $user = User::newFromId( $params['userId'] );
 553                         $user->load();
 554                         if ( !$user->getId() ) {
 555                                 throw new MWException( "No user with ID '{$params['userId']}'." );
 556                         }
 557                 } else { // anon user
 558                         $user = User::newFromName( $params['ip'], false );
 559                 }
 560
 561                 $importSessionFunc = function ( User $user, array $params ) {
 562                         global $wgRequest, $wgUser;
 563
 564                         $context = RequestContext::getMain();
 565                         // Commit and close any current session
 566                         session_write_close(); // persist
 567                         session_id( '' ); // detach
 568                         $_SESSION = array(); // clear in-memory array
 569                         // Remove any user IP or agent information
 570                         $context->setRequest( new FauxRequest() );
 571                         $wgRequest = $context->getRequest(); // b/c
 572                         // Now that all private information is detached from the user, it should
 573                         // be safe to load the new user. If errors occur or an exception is thrown
 574                         // and caught (leaving the main context in a mixed state), there is no risk
 575                         // of the User object being attached to the wrong IP, headers, or session.
 576                         $context->setUser( $user );
 577                         $wgUser = $context->getUser(); // b/c
 578                         if ( strlen( $params['sessionId'] ) ) { // don't make a new random ID
 579                                 wfSetupSession( $params['sessionId'] ); // sets $_SESSION
 580                         }
 581                         $request = new FauxRequest( array(), false, $_SESSION );
 582                         $request->setIP( $params['ip'] );
 583                         foreach ( $params['headers'] as $name => $value ) {
 584                                 $request->setHeader( $name, $value );
 585                         }
 586                         // Set the current context to use the new WebRequest
 587                         $context->setRequest( $request );
 588                         $wgRequest = $context->getRequest(); // b/c
 589                 };
 590
 591                 // Stash the old session and load in the new one
 592                 $oUser = self::getMain()->getUser();
 593                 $oParams = self::getMain()->exportSession();
 594                 $oRequest = self::getMain()->getRequest();
 595                 $importSessionFunc( $user, $params );
 596
 597                 // Set callback to save and close the new session and reload the old one
 598                 return new ScopedCallback(
 599                         function () use ( $importSessionFunc, $oUser, $oParams, $oRequest ) {
 600                                 global $wgRequest;
 601                                 $importSessionFunc( $oUser, $oParams );
 602                                 // Restore the exact previous Request object (instead of leaving FauxRequest)
 603                                 RequestContext::getMain()->setRequest( $oRequest );
 604                                 $wgRequest = RequestContext::getMain()->getRequest(); // b/c
 605                         }
 606                 );
 607         }
 608
 609         /**
 610          * Create a new extraneous context. The context is filled with information
 611          * external to the current session.
 612          * - Title is specified by argument
 613          * - Request is a FauxRequest, or a FauxRequest can be specified by argument
 614          * - User is an anonymous user, for separation IPv4 localhost is used
 615          * - Language will be based on the anonymous user and request, may be content
 616          *   language or a uselang param in the fauxrequest data may change the lang
 617          * - Skin will be based on the anonymous user, should be the wiki's default skin
 618          *
 619          * @param Title $title Title to use for the extraneous request
 620          * @param WebRequest|array $request A WebRequest or data to use for a FauxRequest
 621          * @return RequestContext
 622          */
 623         public static function newExtraneousContext( Title $title, $request = array() ) {
 624                 $context = new self;
 625                 $context->setTitle( $title );
 626                 if ( $request instanceof WebRequest ) {
 627                         $context->setRequest( $request );
 628                 } else {
 629                         $context->setRequest( new FauxRequest( $request ) );
 630                 }
 631                 $context->user = User::newFromName( '127.0.0.1', false );
 632
 633                 return $context;
 634         }
 635 }