includes/OutputPage.php

   1 <?php
   2 /**
   3  * Preparation for the final page rendering.
   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  * @file
  21  */
  22
  23 use MediaWiki\Logger\LoggerFactory;
  24 use MediaWiki\MediaWikiServices;
  25 use MediaWiki\Session\SessionManager;
  26 use WrappedString\WrappedString;
  27 use WrappedString\WrappedStringList;
  28
  29 /**
  30  * This class should be covered by a general architecture document which does
  31  * not exist as of January 2011.  This is one of the Core classes and should
  32  * be read at least once by any new developers.
  33  *
  34  * This class is used to prepare the final rendering. A skin is then
  35  * applied to the output parameters (links, javascript, html, categories ...).
  36  *
  37  * @todo FIXME: Another class handles sending the whole page to the client.
  38  *
  39  * Some comments comes from a pairing session between Zak Greant and Antoine Musso
  40  * in November 2010.
  41  *
  42  * @todo document
  43  */
  44 class OutputPage extends ContextSource {
  45         /** @var array Should be private. Used with addMeta() which adds "<meta>" */
  46         protected $mMetatags = [];
  47
  48         /** @var array */
  49         protected $mLinktags = [];
  50
  51         /** @var bool */
  52         protected $mCanonicalUrl = false;
  53
  54         /**
  55          * @var array Additional stylesheets. Looks like this is for extensions.
  56          *   Might be replaced by ResourceLoader.
  57          */
  58         protected $mExtStyles = [];
  59
  60         /**
  61          * @var string Should be private - has getter and setter. Contains
  62          *   the HTML title */
  63         public $mPagetitle = '';
  64
  65         /**
  66          * @var string Contains all of the "<body>" content. Should be private we
  67          *   got set/get accessors and the append() method.
  68          */
  69         public $mBodytext = '';
  70
  71         /** @var string Stores contents of "<title>" tag */
  72         private $mHTMLtitle = '';
  73
  74         /**
  75          * @var bool Is the displayed content related to the source of the
  76          *   corresponding wiki article.
  77          */
  78         private $mIsarticle = false;
  79
  80         /** @var bool Stores "article flag" toggle. */
  81         private $mIsArticleRelated = true;
  82
  83         /**
  84          * @var bool We have to set isPrintable(). Some pages should
  85          * never be printed (ex: redirections).
  86          */
  87         private $mPrintable = false;
  88
  89         /**
  90          * @var array Contains the page subtitle. Special pages usually have some
  91          *   links here. Don't confuse with site subtitle added by skins.
  92          */
  93         private $mSubtitle = [];
  94
  95         /** @var string */
  96         public $mRedirect = '';
  97
  98         /** @var int */
  99         protected $mStatusCode;
 100
 101         /**
 102          * @var string Used for sending cache control.
 103          *   The whole caching system should probably be moved into its own class.
 104          */
 105         protected $mLastModified = '';
 106
 107         /** @var array */
 108         protected $mCategoryLinks = [];
 109
 110         /** @var array */
 111         protected $mCategories = [
 112                 'hidden' => [],
 113                 'normal' => [],
 114         ];
 115
 116         /** @var array */
 117         protected $mIndicators = [];
 118
 119         /** @var array Array of Interwiki Prefixed (non DB key) Titles (e.g. 'fr:Test page') */
 120         private $mLanguageLinks = [];
 121
 122         /**
 123          * Used for JavaScript (predates ResourceLoader)
 124          * @todo We should split JS / CSS.
 125          * mScripts content is inserted as is in "<head>" by Skin. This might
 126          * contain either a link to a stylesheet or inline CSS.
 127          */
 128         private $mScripts = '';
 129
 130         /** @var string Inline CSS styles. Use addInlineStyle() sparingly */
 131         protected $mInlineStyles = '';
 132
 133         /**
 134          * @var string Used by skin template.
 135          * Example: $tpl->set( 'displaytitle', $out->mPageLinkTitle );
 136          */
 137         public $mPageLinkTitle = '';
 138
 139         /** @var array Array of elements in "<head>". Parser might add its own headers! */
 140         protected $mHeadItems = [];
 141
 142         /** @var array */
 143         protected $mModules = [];
 144
 145         /** @var array */
 146         protected $mModuleScripts = [];
 147
 148         /** @var array */
 149         protected $mModuleStyles = [];
 150
 151         /** @var ResourceLoader */
 152         protected $mResourceLoader;
 153
 154         /** @var ResourceLoaderClientHtml */
 155         private $rlClient;
 156
 157         /** @var ResourceLoaderContext */
 158         private $rlClientContext;
 159
 160         /** @var string */
 161         private $rlUserModuleState;
 162
 163         /** @var array */
 164         private $rlExemptStyleModules;
 165
 166         /** @var array */
 167         protected $mJsConfigVars = [];
 168
 169         /** @var array */
 170         protected $mTemplateIds = [];
 171
 172         /** @var array */
 173         protected $mImageTimeKeys = [];
 174
 175         /** @var string */
 176         public $mRedirectCode = '';
 177
 178         protected $mFeedLinksAppendQuery = null;
 179
 180         /** @var array
 181          * What level of 'untrustworthiness' is allowed in CSS/JS modules loaded on this page?
 182          * @see ResourceLoaderModule::$origin
 183          * ResourceLoaderModule::ORIGIN_ALL is assumed unless overridden;
 184          */
 185         protected $mAllowedModules = [
 186                 ResourceLoaderModule::TYPE_COMBINED => ResourceLoaderModule::ORIGIN_ALL,
 187         ];
 188
 189         /** @var bool Whether output is disabled.  If this is true, the 'output' method will do nothing. */
 190         protected $mDoNothing = false;
 191
 192         // Parser related.
 193
 194         /** @var int */
 195         protected $mContainsNewMagic = 0;
 196
 197         /**
 198          * lazy initialised, use parserOptions()
 199          * @var ParserOptions
 200          */
 201         protected $mParserOptions = null;
 202
 203         /**
 204          * Handles the Atom / RSS links.
 205          * We probably only support Atom in 2011.
 206          * @see $wgAdvertisedFeedTypes
 207          */
 208         private $mFeedLinks = [];
 209
 210         // Gwicke work on squid caching? Roughly from 2003.
 211         protected $mEnableClientCache = true;
 212
 213         /** @var bool Flag if output should only contain the body of the article. */
 214         private $mArticleBodyOnly = false;
 215
 216         /** @var bool */
 217         protected $mNewSectionLink = false;
 218
 219         /** @var bool */
 220         protected $mHideNewSectionLink = false;
 221
 222         /**
 223          * @var bool Comes from the parser. This was probably made to load CSS/JS
 224          * only if we had "<gallery>". Used directly in CategoryPage.php.
 225          * Looks like ResourceLoader can replace this.
 226          */
 227         public $mNoGallery = false;
 228
 229         /** @var string */
 230         private $mPageTitleActionText = '';
 231
 232         /** @var int Cache stuff. Looks like mEnableClientCache */
 233         protected $mCdnMaxage = 0;
 234         /** @var int Upper limit on mCdnMaxage */
 235         protected $mCdnMaxageLimit = INF;
 236
 237         /**
 238          * @var bool Controls if anti-clickjacking / frame-breaking headers will
 239          * be sent. This should be done for pages where edit actions are possible.
 240          * Setters: $this->preventClickjacking() and $this->allowClickjacking().
 241          */
 242         protected $mPreventClickjacking = true;
 243
 244         /** @var int To include the variable {{REVISIONID}} */
 245         private $mRevisionId = null;
 246
 247         /** @var string */
 248         private $mRevisionTimestamp = null;
 249
 250         /** @var array */
 251         protected $mFileVersion = null;
 252
 253         /**
 254          * @var array An array of stylesheet filenames (relative from skins path),
 255          * with options for CSS media, IE conditions, and RTL/LTR direction.
 256          * For internal use; add settings in the skin via $this->addStyle()
 257          *
 258          * Style again! This seems like a code duplication since we already have
 259          * mStyles. This is what makes Open Source amazing.
 260          */
 261         protected $styles = [];
 262
 263         private $mIndexPolicy = 'index';
 264         private $mFollowPolicy = 'follow';
 265         private $mVaryHeader = [
 266                 'Accept-Encoding' => [ 'match=gzip' ],
 267         ];
 268
 269         /**
 270          * If the current page was reached through a redirect, $mRedirectedFrom contains the Title
 271          * of the redirect.
 272          *
 273          * @var Title
 274          */
 275         private $mRedirectedFrom = null;
 276
 277         /**
 278          * Additional key => value data
 279          */
 280         private $mProperties = [];
 281
 282         /**
 283          * @var string|null ResourceLoader target for load.php links. If null, will be omitted
 284          */
 285         private $mTarget = null;
 286
 287         /**
 288          * @var bool Whether parser output should contain table of contents
 289          */
 290         private $mEnableTOC = true;
 291
 292         /**
 293          * @var bool Whether parser output should contain section edit links
 294          */
 295         private $mEnableSectionEditLinks = true;
 296
 297         /**
 298          * @var string|null The URL to send in a <link> element with rel=copyright
 299          */
 300         private $copyrightUrl;
 301
 302         /**
 303          * Constructor for OutputPage. This should not be called directly.
 304          * Instead a new RequestContext should be created and it will implicitly create
 305          * a OutputPage tied to that context.
 306          * @param IContextSource|null $context
 307          */
 308         function __construct( IContextSource $context = null ) {
 309                 if ( $context === null ) {
 310                         # Extensions should use `new RequestContext` instead of `new OutputPage` now.
 311                         wfDeprecated( __METHOD__, '1.18' );
 312                 } else {
 313                         $this->setContext( $context );
 314                 }
 315         }
 316
 317         /**
 318          * Redirect to $url rather than displaying the normal page
 319          *
 320          * @param string $url URL
 321          * @param string $responsecode HTTP status code
 322          */
 323         public function redirect( $url, $responsecode = '302' ) {
 324                 # Strip newlines as a paranoia check for header injection in PHP<5.1.2
 325                 $this->mRedirect = str_replace( "\n", '', $url );
 326                 $this->mRedirectCode = $responsecode;
 327         }
 328
 329         /**
 330          * Get the URL to redirect to, or an empty string if not redirect URL set
 331          *
 332          * @return string
 333          */
 334         public function getRedirect() {
 335                 return $this->mRedirect;
 336         }
 337
 338         /**
 339          * Set the copyright URL to send with the output.
 340          * Empty string to omit, null to reset.
 341          *
 342          * @since 1.26
 343          *
 344          * @param string|null $url
 345          */
 346         public function setCopyrightUrl( $url ) {
 347                 $this->copyrightUrl = $url;
 348         }
 349
 350         /**
 351          * Set the HTTP status code to send with the output.
 352          *
 353          * @param int $statusCode
 354          */
 355         public function setStatusCode( $statusCode ) {
 356                 $this->mStatusCode = $statusCode;
 357         }
 358
 359         /**
 360          * Add a new "<meta>" tag
 361          * To add an http-equiv meta tag, precede the name with "http:"
 362          *
 363          * @param string $name Tag name
 364          * @param string $val Tag value
 365          */
 366         function addMeta( $name, $val ) {
 367                 array_push( $this->mMetatags, [ $name, $val ] );
 368         }
 369
 370         /**
 371          * Returns the current <meta> tags
 372          *
 373          * @since 1.25
 374          * @return array
 375          */
 376         public function getMetaTags() {
 377                 return $this->mMetatags;
 378         }
 379
 380         /**
 381          * Add a new \<link\> tag to the page header.
 382          *
 383          * Note: use setCanonicalUrl() for rel=canonical.
 384          *
 385          * @param array $linkarr Associative array of attributes.
 386          */
 387         function addLink( array $linkarr ) {
 388                 array_push( $this->mLinktags, $linkarr );
 389         }
 390
 391         /**
 392          * Returns the current <link> tags
 393          *
 394          * @since 1.25
 395          * @return array
 396          */
 397         public function getLinkTags() {
 398                 return $this->mLinktags;
 399         }
 400
 401         /**
 402          * Add a new \<link\> with "rel" attribute set to "meta"
 403          *
 404          * @param array $linkarr Associative array mapping attribute names to their
 405          *                 values, both keys and values will be escaped, and the
 406          *                 "rel" attribute will be automatically added
 407          */
 408         function addMetadataLink( array $linkarr ) {
 409                 $linkarr['rel'] = $this->getMetadataAttribute();
 410                 $this->addLink( $linkarr );
 411         }
 412
 413         /**
 414          * Set the URL to be used for the <link rel=canonical>. This should be used
 415          * in preference to addLink(), to avoid duplicate link tags.
 416          * @param string $url
 417          */
 418         function setCanonicalUrl( $url ) {
 419                 $this->mCanonicalUrl = $url;
 420         }
 421
 422         /**
 423          * Returns the URL to be used for the <link rel=canonical> if
 424          * one is set.
 425          *
 426          * @since 1.25
 427          * @return bool|string
 428          */
 429         public function getCanonicalUrl() {
 430                 return $this->mCanonicalUrl;
 431         }
 432
 433         /**
 434          * Get the value of the "rel" attribute for metadata links
 435          *
 436          * @return string
 437          */
 438         public function getMetadataAttribute() {
 439                 # note: buggy CC software only reads first "meta" link
 440                 static $haveMeta = false;
 441                 if ( $haveMeta ) {
 442                         return 'alternate meta';
 443                 } else {
 444                         $haveMeta = true;
 445                         return 'meta';
 446                 }
 447         }
 448
 449         /**
 450          * Add raw HTML to the list of scripts (including \<script\> tag, etc.)
 451          * Internal use only. Use OutputPage::addModules() or OutputPage::addJsConfigVars()
 452          * if possible.
 453          *
 454          * @param string $script Raw HTML
 455          */
 456         function addScript( $script ) {
 457                 $this->mScripts .= $script;
 458         }
 459
 460         /**
 461          * Register and add a stylesheet from an extension directory.
 462          *
 463          * @deprecated since 1.27 use addModuleStyles() or addStyle() instead
 464          * @param string $url Path to sheet.  Provide either a full url (beginning
 465          *             with 'http', etc) or a relative path from the document root
 466          *             (beginning with '/').  Otherwise it behaves identically to
 467          *             addStyle() and draws from the /skins folder.
 468          */
 469         public function addExtensionStyle( $url ) {
 470                 wfDeprecated( __METHOD__, '1.27' );
 471                 array_push( $this->mExtStyles, $url );
 472         }
 473
 474         /**
 475          * Get all styles added by extensions
 476          *
 477          * @deprecated since 1.27
 478          * @return array
 479          */
 480         function getExtStyle() {
 481                 wfDeprecated( __METHOD__, '1.27' );
 482                 return $this->mExtStyles;
 483         }
 484
 485         /**
 486          * Add a JavaScript file out of skins/common, or a given relative path.
 487          * Internal use only. Use OutputPage::addModules() if possible.
 488          *
 489          * @param string $file Filename in skins/common or complete on-server path
 490          *              (/foo/bar.js)
 491          * @param string $version Style version of the file. Defaults to $wgStyleVersion
 492          */
 493         public function addScriptFile( $file, $version = null ) {
 494                 // See if $file parameter is an absolute URL or begins with a slash
 495                 if ( substr( $file, 0, 1 ) == '/' || preg_match( '#^[a-z]*://#i', $file ) ) {
 496                         $path = $file;
 497                 } else {
 498                         $path = $this->getConfig()->get( 'StylePath' ) . "/common/{$file}";
 499                 }
 500                 if ( is_null( $version ) ) {
 501                         $version = $this->getConfig()->get( 'StyleVersion' );
 502                 }
 503                 $this->addScript( Html::linkedScript( wfAppendQuery( $path, $version ) ) );
 504         }
 505
 506         /**
 507          * Add a self-contained script tag with the given contents
 508          * Internal use only. Use OutputPage::addModules() if possible.
 509          *
 510          * @param string $script JavaScript text, no script tags
 511          */
 512         public function addInlineScript( $script ) {
 513                 $this->mScripts .= Html::inlineScript( $script );
 514         }
 515
 516         /**
 517          * Filter an array of modules to remove insufficiently trustworthy members, and modules
 518          * which are no longer registered (eg a page is cached before an extension is disabled)
 519          * @param array $modules
 520          * @param string|null $position If not null, only return modules with this position
 521          * @param string $type
 522          * @return array
 523          */
 524         protected function filterModules( array $modules, $position = null,
 525                 $type = ResourceLoaderModule::TYPE_COMBINED
 526         ) {
 527                 $resourceLoader = $this->getResourceLoader();
 528                 $filteredModules = [];
 529                 foreach ( $modules as $val ) {
 530                         $module = $resourceLoader->getModule( $val );
 531                         if ( $module instanceof ResourceLoaderModule
 532                                 && $module->getOrigin() <= $this->getAllowedModules( $type )
 533                                 && ( is_null( $position ) || $module->getPosition() == $position )
 534                                 && ( !$this->mTarget || in_array( $this->mTarget, $module->getTargets() ) )
 535                         ) {
 536                                 $filteredModules[] = $val;
 537                         }
 538                 }
 539                 return $filteredModules;
 540         }
 541
 542         /**
 543          * Get the list of modules to include on this page
 544          *
 545          * @param bool $filter Whether to filter out insufficiently trustworthy modules
 546          * @param string|null $position If not null, only return modules with this position
 547          * @param string $param
 548          * @return array Array of module names
 549          */
 550         public function getModules( $filter = false, $position = null, $param = 'mModules',
 551                 $type = ResourceLoaderModule::TYPE_COMBINED
 552         ) {
 553                 $modules = array_values( array_unique( $this->$param ) );
 554                 return $filter
 555                         ? $this->filterModules( $modules, $position, $type )
 556                         : $modules;
 557         }
 558
 559         /**
 560          * Add one or more modules recognized by ResourceLoader. Modules added
 561          * through this function will be loaded by ResourceLoader when the
 562          * page loads.
 563          *
 564          * @param string|array $modules Module name (string) or array of module names
 565          */
 566         public function addModules( $modules ) {
 567                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 568         }
 569
 570         /**
 571          * Get the list of module JS to include on this page
 572          *
 573          * @param bool $filter
 574          * @param string|null $position
 575          * @return array Array of module names
 576          */
 577         public function getModuleScripts( $filter = false, $position = null ) {
 578                 return $this->getModules( $filter, $position, 'mModuleScripts',
 579                         ResourceLoaderModule::TYPE_SCRIPTS
 580                 );
 581         }
 582
 583         /**
 584          * Add only JS of one or more modules recognized by ResourceLoader. Module
 585          * scripts added through this function will be loaded by ResourceLoader when
 586          * the page loads.
 587          *
 588          * @param string|array $modules Module name (string) or array of module names
 589          */
 590         public function addModuleScripts( $modules ) {
 591                 $this->mModuleScripts = array_merge( $this->mModuleScripts, (array)$modules );
 592         }
 593
 594         /**
 595          * Get the list of module CSS to include on this page
 596          *
 597          * @param bool $filter
 598          * @param string|null $position
 599          * @return array Array of module names
 600          */
 601         public function getModuleStyles( $filter = false, $position = null ) {
 602                 return $this->getModules( $filter, $position, 'mModuleStyles',
 603                         ResourceLoaderModule::TYPE_STYLES
 604                 );
 605         }
 606
 607         /**
 608          * Add only CSS of one or more modules recognized by ResourceLoader.
 609          *
 610          * Module styles added through this function will be added using standard link CSS
 611          * tags, rather than as a combined Javascript and CSS package. Thus, they will
 612          * load when JavaScript is disabled (unless CSS also happens to be disabled).
 613          *
 614          * @param string|array $modules Module name (string) or array of module names
 615          */
 616         public function addModuleStyles( $modules ) {
 617                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 618         }
 619
 620         /**
 621          * @return null|string ResourceLoader target
 622          */
 623         public function getTarget() {
 624                 return $this->mTarget;
 625         }
 626
 627         /**
 628          * Sets ResourceLoader target for load.php links. If null, will be omitted
 629          *
 630          * @param string|null $target
 631          */
 632         public function setTarget( $target ) {
 633                 $this->mTarget = $target;
 634         }
 635
 636         /**
 637          * Get an array of head items
 638          *
 639          * @return array
 640          */
 641         function getHeadItemsArray() {
 642                 return $this->mHeadItems;
 643         }
 644
 645         /**
 646          * Add or replace a head item to the output
 647          *
 648          * Whenever possible, use more specific options like ResourceLoader modules,
 649          * OutputPage::addLink(), OutputPage::addMetaLink() and OutputPage::addFeedLink()
 650          * Fallback options for those are: OutputPage::addStyle, OutputPage::addScript(),
 651          * OutputPage::addInlineScript() and OutputPage::addInlineStyle()
 652          * This would be your very LAST fallback.
 653          *
 654          * @param string $name Item name
 655          * @param string $value Raw HTML
 656          */
 657         public function addHeadItem( $name, $value ) {
 658                 $this->mHeadItems[$name] = $value;
 659         }
 660
 661         /**
 662          * Add one or more head items to the output
 663          *
 664          * @since 1.28
 665          * @param string|string[] $value Raw HTML
 666          */
 667         public function addHeadItems( $values ) {
 668                 $this->mHeadItems = array_merge( $this->mHeadItems, (array)$values );
 669         }
 670
 671         /**
 672          * Check if the header item $name is already set
 673          *
 674          * @param string $name Item name
 675          * @return bool
 676          */
 677         public function hasHeadItem( $name ) {
 678                 return isset( $this->mHeadItems[$name] );
 679         }
 680
 681         /**
 682          * @deprecated since 1.28 Obsolete - wgUseETag experiment was removed.
 683          * @param string $tag
 684          */
 685         public function setETag( $tag ) {
 686         }
 687
 688         /**
 689          * Set whether the output should only contain the body of the article,
 690          * without any skin, sidebar, etc.
 691          * Used e.g. when calling with "action=render".
 692          *
 693          * @param bool $only Whether to output only the body of the article
 694          */
 695         public function setArticleBodyOnly( $only ) {
 696                 $this->mArticleBodyOnly = $only;
 697         }
 698
 699         /**
 700          * Return whether the output will contain only the body of the article
 701          *
 702          * @return bool
 703          */
 704         public function getArticleBodyOnly() {
 705                 return $this->mArticleBodyOnly;
 706         }
 707
 708         /**
 709          * Set an additional output property
 710          * @since 1.21
 711          *
 712          * @param string $name
 713          * @param mixed $value
 714          */
 715         public function setProperty( $name, $value ) {
 716                 $this->mProperties[$name] = $value;
 717         }
 718
 719         /**
 720          * Get an additional output property
 721          * @since 1.21
 722          *
 723          * @param string $name
 724          * @return mixed Property value or null if not found
 725          */
 726         public function getProperty( $name ) {
 727                 if ( isset( $this->mProperties[$name] ) ) {
 728                         return $this->mProperties[$name];
 729                 } else {
 730                         return null;
 731                 }
 732         }
 733
 734         /**
 735          * checkLastModified tells the client to use the client-cached page if
 736          * possible. If successful, the OutputPage is disabled so that
 737          * any future call to OutputPage->output() have no effect.
 738          *
 739          * Side effect: sets mLastModified for Last-Modified header
 740          *
 741          * @param string $timestamp
 742          *
 743          * @return bool True if cache-ok headers was sent.
 744          */
 745         public function checkLastModified( $timestamp ) {
 746                 if ( !$timestamp || $timestamp == '19700101000000' ) {
 747                         wfDebug( __METHOD__ . ": CACHE DISABLED, NO TIMESTAMP\n" );
 748                         return false;
 749                 }
 750                 $config = $this->getConfig();
 751                 if ( !$config->get( 'CachePages' ) ) {
 752                         wfDebug( __METHOD__ . ": CACHE DISABLED\n" );
 753                         return false;
 754                 }
 755
 756                 $timestamp = wfTimestamp( TS_MW, $timestamp );
 757                 $modifiedTimes = [
 758                         'page' => $timestamp,
 759                         'user' => $this->getUser()->getTouched(),
 760                         'epoch' => $config->get( 'CacheEpoch' )
 761                 ];
 762                 if ( $config->get( 'UseSquid' ) ) {
 763                         // bug 44570: the core page itself may not change, but resources might
 764                         $modifiedTimes['sepoch'] = wfTimestamp( TS_MW, time() - $config->get( 'SquidMaxage' ) );
 765                 }
 766                 Hooks::run( 'OutputPageCheckLastModified', [ &$modifiedTimes, $this ] );
 767
 768                 $maxModified = max( $modifiedTimes );
 769                 $this->mLastModified = wfTimestamp( TS_RFC2822, $maxModified );
 770
 771                 $clientHeader = $this->getRequest()->getHeader( 'If-Modified-Since' );
 772                 if ( $clientHeader === false ) {
 773                         wfDebug( __METHOD__ . ": client did not send If-Modified-Since header", 'private' );
 774                         return false;
 775                 }
 776
 777                 # IE sends sizes after the date like this:
 778                 # Wed, 20 Aug 2003 06:51:19 GMT; length=5202
 779                 # this breaks strtotime().
 780                 $clientHeader = preg_replace( '/;.*$/', '', $clientHeader );
 781
 782                 MediaWiki\suppressWarnings(); // E_STRICT system time bitching
 783                 $clientHeaderTime = strtotime( $clientHeader );
 784                 MediaWiki\restoreWarnings();
 785                 if ( !$clientHeaderTime ) {
 786                         wfDebug( __METHOD__
 787                                 . ": unable to parse the client's If-Modified-Since header: $clientHeader\n" );
 788                         return false;
 789                 }
 790                 $clientHeaderTime = wfTimestamp( TS_MW, $clientHeaderTime );
 791
 792                 # Make debug info
 793                 $info = '';
 794                 foreach ( $modifiedTimes as $name => $value ) {
 795                         if ( $info !== '' ) {
 796                                 $info .= ', ';
 797                         }
 798                         $info .= "$name=" . wfTimestamp( TS_ISO_8601, $value );
 799                 }
 800
 801                 wfDebug( __METHOD__ . ": client sent If-Modified-Since: " .
 802                         wfTimestamp( TS_ISO_8601, $clientHeaderTime ), 'private' );
 803                 wfDebug( __METHOD__ . ": effective Last-Modified: " .
 804                         wfTimestamp( TS_ISO_8601, $maxModified ), 'private' );
 805                 if ( $clientHeaderTime < $maxModified ) {
 806                         wfDebug( __METHOD__ . ": STALE, $info", 'private' );
 807                         return false;
 808                 }
 809
 810                 # Not modified
 811                 # Give a 304 Not Modified response code and disable body output
 812                 wfDebug( __METHOD__ . ": NOT MODIFIED, $info", 'private' );
 813                 ini_set( 'zlib.output_compression', 0 );
 814                 $this->getRequest()->response()->statusHeader( 304 );
 815                 $this->sendCacheControl();
 816                 $this->disable();
 817
 818                 // Don't output a compressed blob when using ob_gzhandler;
 819                 // it's technically against HTTP spec and seems to confuse
 820                 // Firefox when the response gets split over two packets.
 821                 wfClearOutputBuffers();
 822
 823                 return true;
 824         }
 825
 826         /**
 827          * Override the last modified timestamp
 828          *
 829          * @param string $timestamp New timestamp, in a format readable by
 830          *        wfTimestamp()
 831          */
 832         public function setLastModified( $timestamp ) {
 833                 $this->mLastModified = wfTimestamp( TS_RFC2822, $timestamp );
 834         }
 835
 836         /**
 837          * Set the robot policy for the page: <http://www.robotstxt.org/meta.html>
 838          *
 839          * @param string $policy The literal string to output as the contents of
 840          *   the meta tag.  Will be parsed according to the spec and output in
 841          *   standardized form.
 842          * @return null
 843          */
 844         public function setRobotPolicy( $policy ) {
 845                 $policy = Article::formatRobotPolicy( $policy );
 846
 847                 if ( isset( $policy['index'] ) ) {
 848                         $this->setIndexPolicy( $policy['index'] );
 849                 }
 850                 if ( isset( $policy['follow'] ) ) {
 851                         $this->setFollowPolicy( $policy['follow'] );
 852                 }
 853         }
 854
 855         /**
 856          * Set the index policy for the page, but leave the follow policy un-
 857          * touched.
 858          *
 859          * @param string $policy Either 'index' or 'noindex'.
 860          * @return null
 861          */
 862         public function setIndexPolicy( $policy ) {
 863                 $policy = trim( $policy );
 864                 if ( in_array( $policy, [ 'index', 'noindex' ] ) ) {
 865                         $this->mIndexPolicy = $policy;
 866                 }
 867         }
 868
 869         /**
 870          * Set the follow policy for the page, but leave the index policy un-
 871          * touched.
 872          *
 873          * @param string $policy Either 'follow' or 'nofollow'.
 874          * @return null
 875          */
 876         public function setFollowPolicy( $policy ) {
 877                 $policy = trim( $policy );
 878                 if ( in_array( $policy, [ 'follow', 'nofollow' ] ) ) {
 879                         $this->mFollowPolicy = $policy;
 880                 }
 881         }
 882
 883         /**
 884          * Set the new value of the "action text", this will be added to the
 885          * "HTML title", separated from it with " - ".
 886          *
 887          * @param string $text New value of the "action text"
 888          */
 889         public function setPageTitleActionText( $text ) {
 890                 $this->mPageTitleActionText = $text;
 891         }
 892
 893         /**
 894          * Get the value of the "action text"
 895          *
 896          * @return string
 897          */
 898         public function getPageTitleActionText() {
 899                 return $this->mPageTitleActionText;
 900         }
 901
 902         /**
 903          * "HTML title" means the contents of "<title>".
 904          * It is stored as plain, unescaped text and will be run through htmlspecialchars in the skin file.
 905          *
 906          * @param string|Message $name
 907          */
 908         public function setHTMLTitle( $name ) {
 909                 if ( $name instanceof Message ) {
 910                         $this->mHTMLtitle = $name->setContext( $this->getContext() )->text();
 911                 } else {
 912                         $this->mHTMLtitle = $name;
 913                 }
 914         }
 915
 916         /**
 917          * Return the "HTML title", i.e. the content of the "<title>" tag.
 918          *
 919          * @return string
 920          */
 921         public function getHTMLTitle() {
 922                 return $this->mHTMLtitle;
 923         }
 924
 925         /**
 926          * Set $mRedirectedFrom, the Title of the page which redirected us to the current page.
 927          *
 928          * @param Title $t
 929          */
 930         public function setRedirectedFrom( $t ) {
 931                 $this->mRedirectedFrom = $t;
 932         }
 933
 934         /**
 935          * "Page title" means the contents of \<h1\>. It is stored as a valid HTML
 936          * fragment. This function allows good tags like \<sup\> in the \<h1\> tag,
 937          * but not bad tags like \<script\>. This function automatically sets
 938          * \<title\> to the same content as \<h1\> but with all tags removed. Bad
 939          * tags that were escaped in \<h1\> will still be escaped in \<title\>, and
 940          * good tags like \<i\> will be dropped entirely.
 941          *
 942          * @param string|Message $name
 943          */
 944         public function setPageTitle( $name ) {
 945                 if ( $name instanceof Message ) {
 946                         $name = $name->setContext( $this->getContext() )->text();
 947                 }
 948
 949                 # change "<script>foo&bar</script>" to "&lt;script&gt;foo&amp;bar&lt;/script&gt;"
 950                 # but leave "<i>foobar</i>" alone
 951                 $nameWithTags = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $name ) );
 952                 $this->mPagetitle = $nameWithTags;
 953
 954                 # change "<i>foo&amp;bar</i>" to "foo&bar"
 955                 $this->setHTMLTitle(
 956                         $this->msg( 'pagetitle' )->rawParams( Sanitizer::stripAllTags( $nameWithTags ) )
 957                                 ->inContentLanguage()
 958                 );
 959         }
 960
 961         /**
 962          * Return the "page title", i.e. the content of the \<h1\> tag.
 963          *
 964          * @return string
 965          */
 966         public function getPageTitle() {
 967                 return $this->mPagetitle;
 968         }
 969
 970         /**
 971          * Set the Title object to use
 972          *
 973          * @param Title $t
 974          */
 975         public function setTitle( Title $t ) {
 976                 $this->getContext()->setTitle( $t );
 977         }
 978
 979         /**
 980          * Replace the subtitle with $str
 981          *
 982          * @param string|Message $str New value of the subtitle. String should be safe HTML.
 983          */
 984         public function setSubtitle( $str ) {
 985                 $this->clearSubtitle();
 986                 $this->addSubtitle( $str );
 987         }
 988
 989         /**
 990          * Add $str to the subtitle
 991          *
 992          * @param string|Message $str String or Message to add to the subtitle. String should be safe HTML.
 993          */
 994         public function addSubtitle( $str ) {
 995                 if ( $str instanceof Message ) {
 996                         $this->mSubtitle[] = $str->setContext( $this->getContext() )->parse();
 997                 } else {
 998                         $this->mSubtitle[] = $str;
 999                 }
1000         }
1001
1002         /**
1003          * Build message object for a subtitle containing a backlink to a page
1004          *
1005          * @param Title $title Title to link to
1006          * @param array $query Array of additional parameters to include in the link
1007          * @return Message
1008          * @since 1.25
1009          */
1010         public static function buildBacklinkSubtitle( Title $title, $query = [] ) {
1011                 if ( $title->isRedirect() ) {
1012                         $query['redirect'] = 'no';
1013                 }
1014                 $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1015                 return wfMessage( 'backlinksubtitle' )
1016                         ->rawParams( $linkRenderer->makeLink( $title, null, [], $query ) );
1017         }
1018
1019         /**
1020          * Add a subtitle containing a backlink to a page
1021          *
1022          * @param Title $title Title to link to
1023          * @param array $query Array of additional parameters to include in the link
1024          */
1025         public function addBacklinkSubtitle( Title $title, $query = [] ) {
1026                 $this->addSubtitle( self::buildBacklinkSubtitle( $title, $query ) );
1027         }
1028
1029         /**
1030          * Clear the subtitles
1031          */
1032         public function clearSubtitle() {
1033                 $this->mSubtitle = [];
1034         }
1035
1036         /**
1037          * Get the subtitle
1038          *
1039          * @return string
1040          */
1041         public function getSubtitle() {
1042                 return implode( "<br />\n\t\t\t\t", $this->mSubtitle );
1043         }
1044
1045         /**
1046          * Set the page as printable, i.e. it'll be displayed with all
1047          * print styles included
1048          */
1049         public function setPrintable() {
1050                 $this->mPrintable = true;
1051         }
1052
1053         /**
1054          * Return whether the page is "printable"
1055          *
1056          * @return bool
1057          */
1058         public function isPrintable() {
1059                 return $this->mPrintable;
1060         }
1061
1062         /**
1063          * Disable output completely, i.e. calling output() will have no effect
1064          */
1065         public function disable() {
1066                 $this->mDoNothing = true;
1067         }
1068
1069         /**
1070          * Return whether the output will be completely disabled
1071          *
1072          * @return bool
1073          */
1074         public function isDisabled() {
1075                 return $this->mDoNothing;
1076         }
1077
1078         /**
1079          * Show an "add new section" link?
1080          *
1081          * @return bool
1082          */
1083         public function showNewSectionLink() {
1084                 return $this->mNewSectionLink;
1085         }
1086
1087         /**
1088          * Forcibly hide the new section link?
1089          *
1090          * @return bool
1091          */
1092         public function forceHideNewSectionLink() {
1093                 return $this->mHideNewSectionLink;
1094         }
1095
1096         /**
1097          * Add or remove feed links in the page header
1098          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1099          * for the new version
1100          * @see addFeedLink()
1101          *
1102          * @param bool $show True: add default feeds, false: remove all feeds
1103          */
1104         public function setSyndicated( $show = true ) {
1105                 if ( $show ) {
1106                         $this->setFeedAppendQuery( false );
1107                 } else {
1108                         $this->mFeedLinks = [];
1109                 }
1110         }
1111
1112         /**
1113          * Add default feeds to the page header
1114          * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
1115          * for the new version
1116          * @see addFeedLink()
1117          *
1118          * @param string $val Query to append to feed links or false to output
1119          *        default links
1120          */
1121         public function setFeedAppendQuery( $val ) {
1122                 $this->mFeedLinks = [];
1123
1124                 foreach ( $this->getConfig()->get( 'AdvertisedFeedTypes' ) as $type ) {
1125                         $query = "feed=$type";
1126                         if ( is_string( $val ) ) {
1127                                 $query .= '&' . $val;
1128                         }
1129                         $this->mFeedLinks[$type] = $this->getTitle()->getLocalURL( $query );
1130                 }
1131         }
1132
1133         /**
1134          * Add a feed link to the page header
1135          *
1136          * @param string $format Feed type, should be a key of $wgFeedClasses
1137          * @param string $href URL
1138          */
1139         public function addFeedLink( $format, $href ) {
1140                 if ( in_array( $format, $this->getConfig()->get( 'AdvertisedFeedTypes' ) ) ) {
1141                         $this->mFeedLinks[$format] = $href;
1142                 }
1143         }
1144
1145         /**
1146          * Should we output feed links for this page?
1147          * @return bool
1148          */
1149         public function isSyndicated() {
1150                 return count( $this->mFeedLinks ) > 0;
1151         }
1152
1153         /**
1154          * Return URLs for each supported syndication format for this page.
1155          * @return array Associating format keys with URLs
1156          */
1157         public function getSyndicationLinks() {
1158                 return $this->mFeedLinks;
1159         }
1160
1161         /**
1162          * Will currently always return null
1163          *
1164          * @return null
1165          */
1166         public function getFeedAppendQuery() {
1167                 return $this->mFeedLinksAppendQuery;
1168         }
1169
1170         /**
1171          * Set whether the displayed content is related to the source of the
1172          * corresponding article on the wiki
1173          * Setting true will cause the change "article related" toggle to true
1174          *
1175          * @param bool $v
1176          */
1177         public function setArticleFlag( $v ) {
1178                 $this->mIsarticle = $v;
1179                 if ( $v ) {
1180                         $this->mIsArticleRelated = $v;
1181                 }
1182         }
1183
1184         /**
1185          * Return whether the content displayed page is related to the source of
1186          * the corresponding article on the wiki
1187          *
1188          * @return bool
1189          */
1190         public function isArticle() {
1191                 return $this->mIsarticle;
1192         }
1193
1194         /**
1195          * Set whether this page is related an article on the wiki
1196          * Setting false will cause the change of "article flag" toggle to false
1197          *
1198          * @param bool $v
1199          */
1200         public function setArticleRelated( $v ) {
1201                 $this->mIsArticleRelated = $v;
1202                 if ( !$v ) {
1203                         $this->mIsarticle = false;
1204                 }
1205         }
1206
1207         /**
1208          * Return whether this page is related an article on the wiki
1209          *
1210          * @return bool
1211          */
1212         public function isArticleRelated() {
1213                 return $this->mIsArticleRelated;
1214         }
1215
1216         /**
1217          * Add new language links
1218          *
1219          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1220          *                               (e.g. 'fr:Test page')
1221          */
1222         public function addLanguageLinks( array $newLinkArray ) {
1223                 $this->mLanguageLinks += $newLinkArray;
1224         }
1225
1226         /**
1227          * Reset the language links and add new language links
1228          *
1229          * @param string[] $newLinkArray Array of interwiki-prefixed (non DB key) titles
1230          *                               (e.g. 'fr:Test page')
1231          */
1232         public function setLanguageLinks( array $newLinkArray ) {
1233                 $this->mLanguageLinks = $newLinkArray;
1234         }
1235
1236         /**
1237          * Get the list of language links
1238          *
1239          * @return string[] Array of interwiki-prefixed (non DB key) titles (e.g. 'fr:Test page')
1240          */
1241         public function getLanguageLinks() {
1242                 return $this->mLanguageLinks;
1243         }
1244
1245         /**
1246          * Add an array of categories, with names in the keys
1247          *
1248          * @param array $categories Mapping category name => sort key
1249          */
1250         public function addCategoryLinks( array $categories ) {
1251                 global $wgContLang;
1252
1253                 if ( !is_array( $categories ) || count( $categories ) == 0 ) {
1254                         return;
1255                 }
1256
1257                 $res = $this->addCategoryLinksToLBAndGetResult( $categories );
1258
1259                 # Set all the values to 'normal'.
1260                 $categories = array_fill_keys( array_keys( $categories ), 'normal' );
1261
1262                 # Mark hidden categories
1263                 foreach ( $res as $row ) {
1264                         if ( isset( $row->pp_value ) ) {
1265                                 $categories[$row->page_title] = 'hidden';
1266                         }
1267                 }
1268
1269                 # Add the remaining categories to the skin
1270                 if ( Hooks::run(
1271                         'OutputPageMakeCategoryLinks',
1272                         [ &$this, $categories, &$this->mCategoryLinks ] )
1273                 ) {
1274                         $linkRenderer = MediaWikiServices::getInstance()->getLinkRenderer();
1275                         foreach ( $categories as $category => $type ) {
1276                                 // array keys will cast numeric category names to ints, so cast back to string
1277                                 $category = (string)$category;
1278                                 $origcategory = $category;
1279                                 $title = Title::makeTitleSafe( NS_CATEGORY, $category );
1280                                 if ( !$title ) {
1281                                         continue;
1282                                 }
1283                                 $wgContLang->findVariantLink( $category, $title, true );
1284                                 if ( $category != $origcategory && array_key_exists( $category, $categories ) ) {
1285                                         continue;
1286                                 }
1287                                 $text = $wgContLang->convertHtml( $title->getText() );
1288                                 $this->mCategories[$type][] = $title->getText();
1289                                 $this->mCategoryLinks[$type][] = $linkRenderer->makeLink( $title, new HtmlArmor( $text ) );
1290                         }
1291                 }
1292         }
1293
1294         /**
1295          * @param array $categories
1296          * @return bool|ResultWrapper
1297          */
1298         protected function addCategoryLinksToLBAndGetResult( array $categories ) {
1299                 # Add the links to a LinkBatch
1300                 $arr = [ NS_CATEGORY => $categories ];
1301                 $lb = new LinkBatch;
1302                 $lb->setArray( $arr );
1303
1304                 # Fetch existence plus the hiddencat property
1305                 $dbr = wfGetDB( DB_REPLICA );
1306                 $fields = array_merge(
1307                         LinkCache::getSelectFields(),
1308                         [ 'page_namespace', 'page_title', 'pp_value' ]
1309                 );
1310
1311                 $res = $dbr->select( [ 'page', 'page_props' ],
1312                         $fields,
1313                         $lb->constructSet( 'page', $dbr ),
1314                         __METHOD__,
1315                         [],
1316                         [ 'page_props' => [ 'LEFT JOIN', [
1317                                 'pp_propname' => 'hiddencat',
1318                                 'pp_page = page_id'
1319                         ] ] ]
1320                 );
1321
1322                 # Add the results to the link cache
1323                 $lb->addResultToCache( LinkCache::singleton(), $res );
1324
1325                 return $res;
1326         }
1327
1328         /**
1329          * Reset the category links (but not the category list) and add $categories
1330          *
1331          * @param array $categories Mapping category name => sort key
1332          */
1333         public function setCategoryLinks( array $categories ) {
1334                 $this->mCategoryLinks = [];
1335                 $this->addCategoryLinks( $categories );
1336         }
1337
1338         /**
1339          * Get the list of category links, in a 2-D array with the following format:
1340          * $arr[$type][] = $link, where $type is either "normal" or "hidden" (for
1341          * hidden categories) and $link a HTML fragment with a link to the category
1342          * page
1343          *
1344          * @return array
1345          */
1346         public function getCategoryLinks() {
1347                 return $this->mCategoryLinks;
1348         }
1349
1350         /**
1351          * Get the list of category names this page belongs to.
1352          *
1353          * @param string $type The type of categories which should be returned. Possible values:
1354          *  * all: all categories of all types
1355          *  * hidden: only the hidden categories
1356          *  * normal: all categories, except hidden categories
1357          * @return array Array of strings
1358          */
1359         public function getCategories( $type = 'all' ) {
1360                 if ( $type === 'all' ) {
1361                         $allCategories = [];
1362                         foreach ( $this->mCategories as $categories ) {
1363                                 $allCategories = array_merge( $allCategories, $categories );
1364                         }
1365                         return $allCategories;
1366                 }
1367                 if ( !isset( $this->mCategories[$type] ) ) {
1368                         throw new InvalidArgumentException( 'Invalid category type given: ' . $type );
1369                 }
1370                 return $this->mCategories[$type];
1371         }
1372
1373         /**
1374          * Add an array of indicators, with their identifiers as array
1375          * keys and HTML contents as values.
1376          *
1377          * In case of duplicate keys, existing values are overwritten.
1378          *
1379          * @param array $indicators
1380          * @since 1.25
1381          */
1382         public function setIndicators( array $indicators ) {
1383                 $this->mIndicators = $indicators + $this->mIndicators;
1384                 // Keep ordered by key
1385                 ksort( $this->mIndicators );
1386         }
1387
1388         /**
1389          * Get the indicators associated with this page.
1390          *
1391          * The array will be internally ordered by item keys.
1392          *
1393          * @return array Keys: identifiers, values: HTML contents
1394          * @since 1.25
1395          */
1396         public function getIndicators() {
1397                 return $this->mIndicators;
1398         }
1399
1400         /**
1401          * Adds help link with an icon via page indicators.
1402          * Link target can be overridden by a local message containing a wikilink:
1403          * the message key is: lowercase action or special page name + '-helppage'.
1404          * @param string $to Target MediaWiki.org page title or encoded URL.
1405          * @param bool $overrideBaseUrl Whether $url is a full URL, to avoid MW.o.
1406          * @since 1.25
1407          */
1408         public function addHelpLink( $to, $overrideBaseUrl = false ) {
1409                 $this->addModuleStyles( 'mediawiki.helplink' );
1410                 $text = $this->msg( 'helppage-top-gethelp' )->escaped();
1411
1412                 if ( $overrideBaseUrl ) {
1413                         $helpUrl = $to;
1414                 } else {
1415                         $toUrlencoded = wfUrlencode( str_replace( ' ', '_', $to ) );
1416                         $helpUrl = "//www.mediawiki.org/wiki/Special:MyLanguage/$toUrlencoded";
1417                 }
1418
1419                 $link = Html::rawElement(
1420                         'a',
1421                         [
1422                                 'href' => $helpUrl,
1423                                 'target' => '_blank',
1424                                 'class' => 'mw-helplink',
1425                         ],
1426                         $text
1427                 );
1428
1429                 $this->setIndicators( [ 'mw-helplink' => $link ] );
1430         }
1431
1432         /**
1433          * Do not allow scripts which can be modified by wiki users to load on this page;
1434          * only allow scripts bundled with, or generated by, the software.
1435          * Site-wide styles are controlled by a config setting, since they can be
1436          * used to create a custom skin/theme, but not user-specific ones.
1437          *
1438          * @todo this should be given a more accurate name
1439          */
1440         public function disallowUserJs() {
1441                 $this->reduceAllowedModules(
1442                         ResourceLoaderModule::TYPE_SCRIPTS,
1443                         ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
1444                 );
1445
1446                 // Site-wide styles are controlled by a config setting, see bug 71621
1447                 // for background on why. User styles are never allowed.
1448                 if ( $this->getConfig()->get( 'AllowSiteCSSOnRestrictedPages' ) ) {
1449                         $styleOrigin = ResourceLoaderModule::ORIGIN_USER_SITEWIDE;
1450                 } else {
1451                         $styleOrigin = ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL;
1452                 }
1453                 $this->reduceAllowedModules(
1454                         ResourceLoaderModule::TYPE_STYLES,
1455                         $styleOrigin
1456                 );
1457         }
1458
1459         /**
1460          * Show what level of JavaScript / CSS untrustworthiness is allowed on this page
1461          * @see ResourceLoaderModule::$origin
1462          * @param string $type ResourceLoaderModule TYPE_ constant
1463          * @return int ResourceLoaderModule ORIGIN_ class constant
1464          */
1465         public function getAllowedModules( $type ) {
1466                 if ( $type == ResourceLoaderModule::TYPE_COMBINED ) {
1467                         return min( array_values( $this->mAllowedModules ) );
1468                 } else {
1469                         return isset( $this->mAllowedModules[$type] )
1470                                 ? $this->mAllowedModules[$type]
1471                                 : ResourceLoaderModule::ORIGIN_ALL;
1472                 }
1473         }
1474
1475         /**
1476          * Limit the highest level of CSS/JS untrustworthiness allowed.
1477          *
1478          * If passed the same or a higher level than the current level of untrustworthiness set, the
1479          * level will remain unchanged.
1480          *
1481          * @param string $type
1482          * @param int $level ResourceLoaderModule class constant
1483          */
1484         public function reduceAllowedModules( $type, $level ) {
1485                 $this->mAllowedModules[$type] = min( $this->getAllowedModules( $type ), $level );
1486         }
1487
1488         /**
1489          * Prepend $text to the body HTML
1490          *
1491          * @param string $text HTML
1492          */
1493         public function prependHTML( $text ) {
1494                 $this->mBodytext = $text . $this->mBodytext;
1495         }
1496
1497         /**
1498          * Append $text to the body HTML
1499          *
1500          * @param string $text HTML
1501          */
1502         public function addHTML( $text ) {
1503                 $this->mBodytext .= $text;
1504         }
1505
1506         /**
1507          * Shortcut for adding an Html::element via addHTML.
1508          *
1509          * @since 1.19
1510          *
1511          * @param string $element
1512          * @param array $attribs
1513          * @param string $contents
1514          */
1515         public function addElement( $element, array $attribs = [], $contents = '' ) {
1516                 $this->addHTML( Html::element( $element, $attribs, $contents ) );
1517         }
1518
1519         /**
1520          * Clear the body HTML
1521          */
1522         public function clearHTML() {
1523                 $this->mBodytext = '';
1524         }
1525
1526         /**
1527          * Get the body HTML
1528          *
1529          * @return string HTML
1530          */
1531         public function getHTML() {
1532                 return $this->mBodytext;
1533         }
1534
1535         /**
1536          * Get/set the ParserOptions object to use for wikitext parsing
1537          *
1538          * @param ParserOptions|null $options Either the ParserOption to use or null to only get the
1539          *   current ParserOption object
1540          * @return ParserOptions
1541          */
1542         public function parserOptions( $options = null ) {
1543                 if ( $options !== null && !empty( $options->isBogus ) ) {
1544                         // Someone is trying to set a bogus pre-$wgUser PO. Check if it has
1545                         // been changed somehow, and keep it if so.
1546                         $anonPO = ParserOptions::newFromAnon();
1547                         $anonPO->setEditSection( false );
1548                         if ( !$options->matches( $anonPO ) ) {
1549                                 wfLogWarning( __METHOD__ . ': Setting a changed bogus ParserOptions: ' . wfGetAllCallers( 5 ) );
1550                                 $options->isBogus = false;
1551                         }
1552                 }
1553
1554                 if ( !$this->mParserOptions ) {
1555                         if ( !$this->getContext()->getUser()->isSafeToLoad() ) {
1556                                 // $wgUser isn't unstubbable yet, so don't try to get a
1557                                 // ParserOptions for it. And don't cache this ParserOptions
1558                                 // either.
1559                                 $po = ParserOptions::newFromAnon();
1560                                 $po->setEditSection( false );
1561                                 $po->isBogus = true;
1562                                 if ( $options !== null ) {
1563                                         $this->mParserOptions = empty( $options->isBogus ) ? $options : null;
1564                                 }
1565                                 return $po;
1566                         }
1567
1568                         $this->mParserOptions = ParserOptions::newFromContext( $this->getContext() );
1569                         $this->mParserOptions->setEditSection( false );
1570                 }
1571
1572                 if ( $options !== null && !empty( $options->isBogus ) ) {
1573                         // They're trying to restore the bogus pre-$wgUser PO. Do the right
1574                         // thing.
1575                         return wfSetVar( $this->mParserOptions, null, true );
1576                 } else {
1577                         return wfSetVar( $this->mParserOptions, $options );
1578                 }
1579         }
1580
1581         /**
1582          * Set the revision ID which will be seen by the wiki text parser
1583          * for things such as embedded {{REVISIONID}} variable use.
1584          *
1585          * @param int|null $revid An positive integer, or null
1586          * @return mixed Previous value
1587          */
1588         public function setRevisionId( $revid ) {
1589                 $val = is_null( $revid ) ? null : intval( $revid );
1590                 return wfSetVar( $this->mRevisionId, $val );
1591         }
1592
1593         /**
1594          * Get the displayed revision ID
1595          *
1596          * @return int
1597          */
1598         public function getRevisionId() {
1599                 return $this->mRevisionId;
1600         }
1601
1602         /**
1603          * Set the timestamp of the revision which will be displayed. This is used
1604          * to avoid a extra DB call in Skin::lastModified().
1605          *
1606          * @param string|null $timestamp
1607          * @return mixed Previous value
1608          */
1609         public function setRevisionTimestamp( $timestamp ) {
1610                 return wfSetVar( $this->mRevisionTimestamp, $timestamp );
1611         }
1612
1613         /**
1614          * Get the timestamp of displayed revision.
1615          * This will be null if not filled by setRevisionTimestamp().
1616          *
1617          * @return string|null
1618          */
1619         public function getRevisionTimestamp() {
1620                 return $this->mRevisionTimestamp;
1621         }
1622
1623         /**
1624          * Set the displayed file version
1625          *
1626          * @param File|bool $file
1627          * @return mixed Previous value
1628          */
1629         public function setFileVersion( $file ) {
1630                 $val = null;
1631                 if ( $file instanceof File && $file->exists() ) {
1632                         $val = [ 'time' => $file->getTimestamp(), 'sha1' => $file->getSha1() ];
1633                 }
1634                 return wfSetVar( $this->mFileVersion, $val, true );
1635         }
1636
1637         /**
1638          * Get the displayed file version
1639          *
1640          * @return array|null ('time' => MW timestamp, 'sha1' => sha1)
1641          */
1642         public function getFileVersion() {
1643                 return $this->mFileVersion;
1644         }
1645
1646         /**
1647          * Get the templates used on this page
1648          *
1649          * @return array (namespace => dbKey => revId)
1650          * @since 1.18
1651          */
1652         public function getTemplateIds() {
1653                 return $this->mTemplateIds;
1654         }
1655
1656         /**
1657          * Get the files used on this page
1658          *
1659          * @return array (dbKey => array('time' => MW timestamp or null, 'sha1' => sha1 or ''))
1660          * @since 1.18
1661          */
1662         public function getFileSearchOptions() {
1663                 return $this->mImageTimeKeys;
1664         }
1665
1666         /**
1667          * Convert wikitext to HTML and add it to the buffer
1668          * Default assumes that the current page title will be used.
1669          *
1670          * @param string $text
1671          * @param bool $linestart Is this the start of a line?
1672          * @param bool $interface Is this text in the user interface language?
1673          * @throws MWException
1674          */
1675         public function addWikiText( $text, $linestart = true, $interface = true ) {
1676                 $title = $this->getTitle(); // Work around E_STRICT
1677                 if ( !$title ) {
1678                         throw new MWException( 'Title is null' );
1679                 }
1680                 $this->addWikiTextTitle( $text, $title, $linestart, /*tidy*/false, $interface );
1681         }
1682
1683         /**
1684          * Add wikitext with a custom Title object
1685          *
1686          * @param string $text Wikitext
1687          * @param Title $title
1688          * @param bool $linestart Is this the start of a line?
1689          */
1690         public function addWikiTextWithTitle( $text, &$title, $linestart = true ) {
1691                 $this->addWikiTextTitle( $text, $title, $linestart );
1692         }
1693
1694         /**
1695          * Add wikitext with a custom Title object and tidy enabled.
1696          *
1697          * @param string $text Wikitext
1698          * @param Title $title
1699          * @param bool $linestart Is this the start of a line?
1700          */
1701         function addWikiTextTitleTidy( $text, &$title, $linestart = true ) {
1702                 $this->addWikiTextTitle( $text, $title, $linestart, true );
1703         }
1704
1705         /**
1706          * Add wikitext with tidy enabled
1707          *
1708          * @param string $text Wikitext
1709          * @param bool $linestart Is this the start of a line?
1710          */
1711         public function addWikiTextTidy( $text, $linestart = true ) {
1712                 $title = $this->getTitle();
1713                 $this->addWikiTextTitleTidy( $text, $title, $linestart );
1714         }
1715
1716         /**
1717          * Add wikitext with a custom Title object
1718          *
1719          * @param string $text Wikitext
1720          * @param Title $title
1721          * @param bool $linestart Is this the start of a line?
1722          * @param bool $tidy Whether to use tidy
1723          * @param bool $interface Whether it is an interface message
1724          *   (for example disables conversion)
1725          */
1726         public function addWikiTextTitle( $text, Title $title, $linestart,
1727                 $tidy = false, $interface = false
1728         ) {
1729                 global $wgParser;
1730
1731                 $popts = $this->parserOptions();
1732                 $oldTidy = $popts->setTidy( $tidy );
1733                 $popts->setInterfaceMessage( (bool)$interface );
1734
1735                 $parserOutput = $wgParser->getFreshParser()->parse(
1736                         $text, $title, $popts,
1737                         $linestart, true, $this->mRevisionId
1738                 );
1739
1740                 $popts->setTidy( $oldTidy );
1741
1742                 $this->addParserOutput( $parserOutput );
1743         }
1744
1745         /**
1746          * Add a ParserOutput object, but without Html.
1747          *
1748          * @deprecated since 1.24, use addParserOutputMetadata() instead.
1749          * @param ParserOutput $parserOutput
1750          */
1751         public function addParserOutputNoText( $parserOutput ) {
1752                 wfDeprecated( __METHOD__, '1.24' );
1753                 $this->addParserOutputMetadata( $parserOutput );
1754         }
1755
1756         /**
1757          * Add all metadata associated with a ParserOutput object, but without the actual HTML. This
1758          * includes categories, language links, ResourceLoader modules, effects of certain magic words,
1759          * and so on.
1760          *
1761          * @since 1.24
1762          * @param ParserOutput $parserOutput
1763          */
1764         public function addParserOutputMetadata( $parserOutput ) {
1765                 $this->mLanguageLinks += $parserOutput->getLanguageLinks();
1766                 $this->addCategoryLinks( $parserOutput->getCategories() );
1767                 $this->setIndicators( $parserOutput->getIndicators() );
1768                 $this->mNewSectionLink = $parserOutput->getNewSection();
1769                 $this->mHideNewSectionLink = $parserOutput->getHideNewSection();
1770
1771                 if ( !$parserOutput->isCacheable() ) {
1772                         $this->enableClientCache( false );
1773                 }
1774                 $this->mNoGallery = $parserOutput->getNoGallery();
1775                 $this->mHeadItems = array_merge( $this->mHeadItems, $parserOutput->getHeadItems() );
1776                 $this->addModules( $parserOutput->getModules() );
1777                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1778                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1779                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1780                 $this->mPreventClickjacking = $this->mPreventClickjacking
1781                         || $parserOutput->preventClickjacking();
1782
1783                 // Template versioning...
1784                 foreach ( (array)$parserOutput->getTemplateIds() as $ns => $dbks ) {
1785                         if ( isset( $this->mTemplateIds[$ns] ) ) {
1786                                 $this->mTemplateIds[$ns] = $dbks + $this->mTemplateIds[$ns];
1787                         } else {
1788                                 $this->mTemplateIds[$ns] = $dbks;
1789                         }
1790                 }
1791                 // File versioning...
1792                 foreach ( (array)$parserOutput->getFileSearchOptions() as $dbk => $data ) {
1793                         $this->mImageTimeKeys[$dbk] = $data;
1794                 }
1795
1796                 // Hooks registered in the object
1797                 $parserOutputHooks = $this->getConfig()->get( 'ParserOutputHooks' );
1798                 foreach ( $parserOutput->getOutputHooks() as $hookInfo ) {
1799                         list( $hookName, $data ) = $hookInfo;
1800                         if ( isset( $parserOutputHooks[$hookName] ) ) {
1801                                 call_user_func( $parserOutputHooks[$hookName], $this, $parserOutput, $data );
1802                         }
1803                 }
1804
1805                 // enable OOUI if requested via ParserOutput
1806                 if ( $parserOutput->getEnableOOUI() ) {
1807                         $this->enableOOUI();
1808                 }
1809
1810                 // Link flags are ignored for now, but may in the future be
1811                 // used to mark individual language links.
1812                 $linkFlags = [];
1813                 Hooks::run( 'LanguageLinks', [ $this->getTitle(), &$this->mLanguageLinks, &$linkFlags ] );
1814                 Hooks::run( 'OutputPageParserOutput', [ &$this, $parserOutput ] );
1815         }
1816
1817         /**
1818          * Add the HTML and enhancements for it (like ResourceLoader modules) associated with a
1819          * ParserOutput object, without any other metadata.
1820          *
1821          * @since 1.24
1822          * @param ParserOutput $parserOutput
1823          */
1824         public function addParserOutputContent( $parserOutput ) {
1825                 $this->addParserOutputText( $parserOutput );
1826
1827                 $this->addModules( $parserOutput->getModules() );
1828                 $this->addModuleScripts( $parserOutput->getModuleScripts() );
1829                 $this->addModuleStyles( $parserOutput->getModuleStyles() );
1830
1831                 $this->addJsConfigVars( $parserOutput->getJsConfigVars() );
1832         }
1833
1834         /**
1835          * Add the HTML associated with a ParserOutput object, without any metadata.
1836          *
1837          * @since 1.24
1838          * @param ParserOutput $parserOutput
1839          */
1840         public function addParserOutputText( $parserOutput ) {
1841                 $text = $parserOutput->getText();
1842                 Hooks::run( 'OutputPageBeforeHTML', [ &$this, &$text ] );
1843                 $this->addHTML( $text );
1844         }
1845
1846         /**
1847          * Add everything from a ParserOutput object.
1848          *
1849          * @param ParserOutput $parserOutput
1850          */
1851         function addParserOutput( $parserOutput ) {
1852                 $this->addParserOutputMetadata( $parserOutput );
1853                 $parserOutput->setTOCEnabled( $this->mEnableTOC );
1854
1855                 // Touch section edit links only if not previously disabled
1856                 if ( $parserOutput->getEditSectionTokens() ) {
1857                         $parserOutput->setEditSectionTokens( $this->mEnableSectionEditLinks );
1858                 }
1859
1860                 $this->addParserOutputText( $parserOutput );
1861         }
1862
1863         /**
1864          * Add the output of a QuickTemplate to the output buffer
1865          *
1866          * @param QuickTemplate $template
1867          */
1868         public function addTemplate( &$template ) {
1869                 $this->addHTML( $template->getHTML() );
1870         }
1871
1872         /**
1873          * Parse wikitext and return the HTML.
1874          *
1875          * @param string $text
1876          * @param bool $linestart Is this the start of a line?
1877          * @param bool $interface Use interface language ($wgLang instead of
1878          *   $wgContLang) while parsing language sensitive magic words like GRAMMAR and PLURAL.
1879          *   This also disables LanguageConverter.
1880          * @param Language $language Target language object, will override $interface
1881          * @throws MWException
1882          * @return string HTML
1883          */
1884         public function parse( $text, $linestart = true, $interface = false, $language = null ) {
1885                 global $wgParser;
1886
1887                 if ( is_null( $this->getTitle() ) ) {
1888                         throw new MWException( 'Empty $mTitle in ' . __METHOD__ );
1889                 }
1890
1891                 $popts = $this->parserOptions();
1892                 if ( $interface ) {
1893                         $popts->setInterfaceMessage( true );
1894                 }
1895                 if ( $language !== null ) {
1896                         $oldLang = $popts->setTargetLanguage( $language );
1897                 }
1898
1899                 $parserOutput = $wgParser->getFreshParser()->parse(
1900                         $text, $this->getTitle(), $popts,
1901                         $linestart, true, $this->mRevisionId
1902                 );
1903
1904                 if ( $interface ) {
1905                         $popts->setInterfaceMessage( false );
1906                 }
1907                 if ( $language !== null ) {
1908                         $popts->setTargetLanguage( $oldLang );
1909                 }
1910
1911                 return $parserOutput->getText();
1912         }
1913
1914         /**
1915          * Parse wikitext, strip paragraphs, and return the HTML.
1916          *
1917          * @param string $text
1918          * @param bool $linestart Is this the start of a line?
1919          * @param bool $interface Use interface language ($wgLang instead of
1920          *   $wgContLang) while parsing language sensitive magic
1921          *   words like GRAMMAR and PLURAL
1922          * @return string HTML
1923          */
1924         public function parseInline( $text, $linestart = true, $interface = false ) {
1925                 $parsed = $this->parse( $text, $linestart, $interface );
1926                 return Parser::stripOuterParagraph( $parsed );
1927         }
1928
1929         /**
1930          * @param $maxage
1931          * @deprecated since 1.27 Use setCdnMaxage() instead
1932          */
1933         public function setSquidMaxage( $maxage ) {
1934                 $this->setCdnMaxage( $maxage );
1935         }
1936
1937         /**
1938          * Set the value of the "s-maxage" part of the "Cache-control" HTTP header
1939          *
1940          * @param int $maxage Maximum cache time on the CDN, in seconds.
1941          */
1942         public function setCdnMaxage( $maxage ) {
1943                 $this->mCdnMaxage = min( $maxage, $this->mCdnMaxageLimit );
1944         }
1945
1946         /**
1947          * Lower the value of the "s-maxage" part of the "Cache-control" HTTP header
1948          *
1949          * @param int $maxage Maximum cache time on the CDN, in seconds
1950          * @since 1.27
1951          */
1952         public function lowerCdnMaxage( $maxage ) {
1953                 $this->mCdnMaxageLimit = min( $maxage, $this->mCdnMaxageLimit );
1954                 $this->setCdnMaxage( $this->mCdnMaxage );
1955         }
1956
1957         /**
1958          * Get TTL in [$minTTL,$maxTTL] in pass it to lowerCdnMaxage()
1959          *
1960          * This sets and returns $minTTL if $mtime is false or null. Otherwise,
1961          * the TTL is higher the older the $mtime timestamp is. Essentially, the
1962          * TTL is 90% of the age of the object, subject to the min and max.
1963          *
1964          * @param string|integer|float|bool|null $mtime Last-Modified timestamp
1965          * @param integer $minTTL Mimimum TTL in seconds [default: 1 minute]
1966          * @param integer $maxTTL Maximum TTL in seconds [default: $wgSquidMaxage]
1967          * @return integer TTL in seconds
1968          * @since 1.28
1969          */
1970         public function adaptCdnTTL( $mtime, $minTTL = 0, $maxTTL = 0 ) {
1971                 $minTTL = $minTTL ?: IExpiringStore::TTL_MINUTE;
1972                 $maxTTL = $maxTTL ?: $this->getConfig()->get( 'SquidMaxage' );
1973
1974                 if ( $mtime === null || $mtime === false ) {
1975                         return $minTTL; // entity does not exist
1976                 }
1977
1978                 $age = time() - wfTimestamp( TS_UNIX, $mtime );
1979                 $adaptiveTTL = max( .9 * $age, $minTTL );
1980                 $adaptiveTTL = min( $adaptiveTTL, $maxTTL );
1981
1982                 $this->lowerCdnMaxage( (int)$adaptiveTTL );
1983
1984                 return $adaptiveTTL;
1985         }
1986
1987         /**
1988          * Use enableClientCache(false) to force it to send nocache headers
1989          *
1990          * @param bool $state
1991          *
1992          * @return bool
1993          */
1994         public function enableClientCache( $state ) {
1995                 return wfSetVar( $this->mEnableClientCache, $state );
1996         }
1997
1998         /**
1999          * Get the list of cookies that will influence on the cache
2000          *
2001          * @return array
2002          */
2003         function getCacheVaryCookies() {
2004                 static $cookies;
2005                 if ( $cookies === null ) {
2006                         $config = $this->getConfig();
2007                         $cookies = array_merge(
2008                                 SessionManager::singleton()->getVaryCookies(),
2009                                 [
2010                                         'forceHTTPS',
2011                                 ],
2012                                 $config->get( 'CacheVaryCookies' )
2013                         );
2014                         Hooks::run( 'GetCacheVaryCookies', [ $this, &$cookies ] );
2015                 }
2016                 return $cookies;
2017         }
2018
2019         /**
2020          * Check if the request has a cache-varying cookie header
2021          * If it does, it's very important that we don't allow public caching
2022          *
2023          * @return bool
2024          */
2025         function haveCacheVaryCookies() {
2026                 $request = $this->getRequest();
2027                 foreach ( $this->getCacheVaryCookies() as $cookieName ) {
2028                         if ( $request->getCookie( $cookieName, '', '' ) !== '' ) {
2029                                 wfDebug( __METHOD__ . ": found $cookieName\n" );
2030                                 return true;
2031                         }
2032                 }
2033                 wfDebug( __METHOD__ . ": no cache-varying cookies found\n" );
2034                 return false;
2035         }
2036
2037         /**
2038          * Add an HTTP header that will influence on the cache
2039          *
2040          * @param string $header Header name
2041          * @param string[]|null $option Options for the Key header. See
2042          * https://datatracker.ietf.org/doc/draft-fielding-http-key/
2043          * for the list of valid options.
2044          */
2045         public function addVaryHeader( $header, array $option = null ) {
2046                 if ( !array_key_exists( $header, $this->mVaryHeader ) ) {
2047                         $this->mVaryHeader[$header] = [];
2048                 }
2049                 if ( !is_array( $option ) ) {
2050                         $option = [];
2051                 }
2052                 $this->mVaryHeader[$header] = array_unique( array_merge( $this->mVaryHeader[$header], $option ) );
2053         }
2054
2055         /**
2056          * Return a Vary: header on which to vary caches. Based on the keys of $mVaryHeader,
2057          * such as Accept-Encoding or Cookie
2058          *
2059          * @return string
2060          */
2061         public function getVaryHeader() {
2062                 // If we vary on cookies, let's make sure it's always included here too.
2063                 if ( $this->getCacheVaryCookies() ) {
2064                         $this->addVaryHeader( 'Cookie' );
2065                 }
2066
2067                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2068                         $this->addVaryHeader( $header, $options );
2069                 }
2070                 return 'Vary: ' . implode( ', ', array_keys( $this->mVaryHeader ) );
2071         }
2072
2073         /**
2074          * Get a complete Key header
2075          *
2076          * @return string
2077          */
2078         public function getKeyHeader() {
2079                 $cvCookies = $this->getCacheVaryCookies();
2080
2081                 $cookiesOption = [];
2082                 foreach ( $cvCookies as $cookieName ) {
2083                         $cookiesOption[] = 'param=' . $cookieName;
2084                 }
2085                 $this->addVaryHeader( 'Cookie', $cookiesOption );
2086
2087                 foreach ( SessionManager::singleton()->getVaryHeaders() as $header => $options ) {
2088                         $this->addVaryHeader( $header, $options );
2089                 }
2090
2091                 $headers = [];
2092                 foreach ( $this->mVaryHeader as $header => $option ) {
2093                         $newheader = $header;
2094                         if ( is_array( $option ) && count( $option ) > 0 ) {
2095                                 $newheader .= ';' . implode( ';', $option );
2096                         }
2097                         $headers[] = $newheader;
2098                 }
2099                 $key = 'Key: ' . implode( ',', $headers );
2100
2101                 return $key;
2102         }
2103
2104         /**
2105          * T23672: Add Accept-Language to Vary and Key headers
2106          * if there's no 'variant' parameter existed in GET.
2107          *
2108          * For example:
2109          *   /w/index.php?title=Main_page should always be served; but
2110          *   /w/index.php?title=Main_page&variant=zh-cn should never be served.
2111          */
2112         function addAcceptLanguage() {
2113                 $title = $this->getTitle();
2114                 if ( !$title instanceof Title ) {
2115                         return;
2116                 }
2117
2118                 $lang = $title->getPageLanguage();
2119                 if ( !$this->getRequest()->getCheck( 'variant' ) && $lang->hasVariants() ) {
2120                         $variants = $lang->getVariants();
2121                         $aloption = [];
2122                         foreach ( $variants as $variant ) {
2123                                 if ( $variant === $lang->getCode() ) {
2124                                         continue;
2125                                 } else {
2126                                         $aloption[] = 'substr=' . $variant;
2127
2128                                         // IE and some other browsers use BCP 47 standards in
2129                                         // their Accept-Language header, like "zh-CN" or "zh-Hant".
2130                                         // We should handle these too.
2131                                         $variantBCP47 = wfBCP47( $variant );
2132                                         if ( $variantBCP47 !== $variant ) {
2133                                                 $aloption[] = 'substr=' . $variantBCP47;
2134                                         }
2135                                 }
2136                         }
2137                         $this->addVaryHeader( 'Accept-Language', $aloption );
2138                 }
2139         }
2140
2141         /**
2142          * Set a flag which will cause an X-Frame-Options header appropriate for
2143          * edit pages to be sent. The header value is controlled by
2144          * $wgEditPageFrameOptions.
2145          *
2146          * This is the default for special pages. If you display a CSRF-protected
2147          * form on an ordinary view page, then you need to call this function.
2148          *
2149          * @param bool $enable
2150          */
2151         public function preventClickjacking( $enable = true ) {
2152                 $this->mPreventClickjacking = $enable;
2153         }
2154
2155         /**
2156          * Turn off frame-breaking. Alias for $this->preventClickjacking(false).
2157          * This can be called from pages which do not contain any CSRF-protected
2158          * HTML form.
2159          */
2160         public function allowClickjacking() {
2161                 $this->mPreventClickjacking = false;
2162         }
2163
2164         /**
2165          * Get the prevent-clickjacking flag
2166          *
2167          * @since 1.24
2168          * @return bool
2169          */
2170         public function getPreventClickjacking() {
2171                 return $this->mPreventClickjacking;
2172         }
2173
2174         /**
2175          * Get the X-Frame-Options header value (without the name part), or false
2176          * if there isn't one. This is used by Skin to determine whether to enable
2177          * JavaScript frame-breaking, for clients that don't support X-Frame-Options.
2178          *
2179          * @return string
2180          */
2181         public function getFrameOptions() {
2182                 $config = $this->getConfig();
2183                 if ( $config->get( 'BreakFrames' ) ) {
2184                         return 'DENY';
2185                 } elseif ( $this->mPreventClickjacking && $config->get( 'EditPageFrameOptions' ) ) {
2186                         return $config->get( 'EditPageFrameOptions' );
2187                 }
2188                 return false;
2189         }
2190
2191         /**
2192          * Send cache control HTTP headers
2193          */
2194         public function sendCacheControl() {
2195                 $response = $this->getRequest()->response();
2196                 $config = $this->getConfig();
2197
2198                 $this->addVaryHeader( 'Cookie' );
2199                 $this->addAcceptLanguage();
2200
2201                 # don't serve compressed data to clients who can't handle it
2202                 # maintain different caches for logged-in users and non-logged in ones
2203                 $response->header( $this->getVaryHeader() );
2204
2205                 if ( $config->get( 'UseKeyHeader' ) ) {
2206                         $response->header( $this->getKeyHeader() );
2207                 }
2208
2209                 if ( $this->mEnableClientCache ) {
2210                         if (
2211                                 $config->get( 'UseSquid' ) &&
2212                                 !$response->hasCookies() &&
2213                                 !SessionManager::getGlobalSession()->isPersistent() &&
2214                                 !$this->isPrintable() &&
2215                                 $this->mCdnMaxage != 0 &&
2216                                 !$this->haveCacheVaryCookies()
2217                         ) {
2218                                 if ( $config->get( 'UseESI' ) ) {
2219                                         # We'll purge the proxy cache explicitly, but require end user agents
2220                                         # to revalidate against the proxy on each visit.
2221                                         # Surrogate-Control controls our CDN, Cache-Control downstream caches
2222                                         wfDebug( __METHOD__ .
2223                                                 ": proxy caching with ESI; {$this->mLastModified} **", 'private' );
2224                                         # start with a shorter timeout for initial testing
2225                                         # header( 'Surrogate-Control: max-age=2678400+2678400, content="ESI/1.0"');
2226                                         $response->header(
2227                                                 "Surrogate-Control: max-age={$config->get( 'SquidMaxage' )}" .
2228                                                 "+{$this->mCdnMaxage}, content=\"ESI/1.0\""
2229                                         );
2230                                         $response->header( 'Cache-Control: s-maxage=0, must-revalidate, max-age=0' );
2231                                 } else {
2232                                         # We'll purge the proxy cache for anons explicitly, but require end user agents
2233                                         # to revalidate against the proxy on each visit.
2234                                         # IMPORTANT! The CDN needs to replace the Cache-Control header with
2235                                         # Cache-Control: s-maxage=0, must-revalidate, max-age=0
2236                                         wfDebug( __METHOD__ .
2237                                                 ": local proxy caching; {$this->mLastModified} **", 'private' );
2238                                         # start with a shorter timeout for initial testing
2239                                         # header( "Cache-Control: s-maxage=2678400, must-revalidate, max-age=0" );
2240                                         $response->header( "Cache-Control: " .
2241                                                 "s-maxage={$this->mCdnMaxage}, must-revalidate, max-age=0" );
2242                                 }
2243                         } else {
2244                                 # We do want clients to cache if they can, but they *must* check for updates
2245                                 # on revisiting the page.
2246                                 wfDebug( __METHOD__ . ": private caching; {$this->mLastModified} **", 'private' );
2247                                 $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2248                                 $response->header( "Cache-Control: private, must-revalidate, max-age=0" );
2249                         }
2250                         if ( $this->mLastModified ) {
2251                                 $response->header( "Last-Modified: {$this->mLastModified}" );
2252                         }
2253                 } else {
2254                         wfDebug( __METHOD__ . ": no caching **", 'private' );
2255
2256                         # In general, the absence of a last modified header should be enough to prevent
2257                         # the client from using its cache. We send a few other things just to make sure.
2258                         $response->header( 'Expires: ' . gmdate( 'D, d M Y H:i:s', 0 ) . ' GMT' );
2259                         $response->header( 'Cache-Control: no-cache, no-store, max-age=0, must-revalidate' );
2260                         $response->header( 'Pragma: no-cache' );
2261                 }
2262         }
2263
2264         /**
2265          * Finally, all the text has been munged and accumulated into
2266          * the object, let's actually output it:
2267          *
2268          * @param bool $return Set to true to get the result as a string rather than sending it
2269          * @return string|null
2270          * @throws Exception
2271          * @throws FatalError
2272          * @throws MWException
2273          */
2274         public function output( $return = false ) {
2275                 global $wgContLang;
2276
2277                 if ( $this->mDoNothing ) {
2278                         return $return ? '' : null;
2279                 }
2280
2281                 $response = $this->getRequest()->response();
2282                 $config = $this->getConfig();
2283
2284                 if ( $this->mRedirect != '' ) {
2285                         # Standards require redirect URLs to be absolute
2286                         $this->mRedirect = wfExpandUrl( $this->mRedirect, PROTO_CURRENT );
2287
2288                         $redirect = $this->mRedirect;
2289                         $code = $this->mRedirectCode;
2290
2291                         if ( Hooks::run( "BeforePageRedirect", [ $this, &$redirect, &$code ] ) ) {
2292                                 if ( $code == '301' || $code == '303' ) {
2293                                         if ( !$config->get( 'DebugRedirects' ) ) {
2294                                                 $response->statusHeader( $code );
2295                                         }
2296                                         $this->mLastModified = wfTimestamp( TS_RFC2822 );
2297                                 }
2298                                 if ( $config->get( 'VaryOnXFP' ) ) {
2299                                         $this->addVaryHeader( 'X-Forwarded-Proto' );
2300                                 }
2301                                 $this->sendCacheControl();
2302
2303                                 $response->header( "Content-Type: text/html; charset=utf-8" );
2304                                 if ( $config->get( 'DebugRedirects' ) ) {
2305                                         $url = htmlspecialchars( $redirect );
2306                                         print "<html>\n<head>\n<title>Redirect</title>\n</head>\n<body>\n";
2307                                         print "<p>Location: <a href=\"$url\">$url</a></p>\n";
2308                                         print "</body>\n</html>\n";
2309                                 } else {
2310                                         $response->header( 'Location: ' . $redirect );
2311                                 }
2312                         }
2313
2314                         return $return ? '' : null;
2315                 } elseif ( $this->mStatusCode ) {
2316                         $response->statusHeader( $this->mStatusCode );
2317                 }
2318
2319                 # Buffer output; final headers may depend on later processing
2320                 ob_start();
2321
2322                 $response->header( 'Content-type: ' . $config->get( 'MimeType' ) . '; charset=UTF-8' );
2323                 $response->header( 'Content-language: ' . $wgContLang->getHtmlCode() );
2324
2325                 // Avoid Internet Explorer "compatibility view" in IE 8-10, so that
2326                 // jQuery etc. can work correctly.
2327                 $response->header( 'X-UA-Compatible: IE=Edge' );
2328
2329                 // Prevent framing, if requested
2330                 $frameOptions = $this->getFrameOptions();
2331                 if ( $frameOptions ) {
2332                         $response->header( "X-Frame-Options: $frameOptions" );
2333                 }
2334
2335                 if ( $this->mArticleBodyOnly ) {
2336                         echo $this->mBodytext;
2337                 } else {
2338                         $sk = $this->getSkin();
2339                         // add skin specific modules
2340                         $modules = $sk->getDefaultModules();
2341
2342                         // Enforce various default modules for all pages and all skins
2343                         $coreModules = [
2344                                 // Keep this list as small as possible
2345                                 'site',
2346                                 'mediawiki.page.startup',
2347                                 'mediawiki.user',
2348                         ];
2349
2350                         // Support for high-density display images if enabled
2351                         if ( $config->get( 'ResponsiveImages' ) ) {
2352                                 $coreModules[] = 'mediawiki.hidpi';
2353                         }
2354
2355                         $this->addModules( $coreModules );
2356                         foreach ( $modules as $group ) {
2357                                 $this->addModules( $group );
2358                         }
2359                         MWDebug::addModules( $this );
2360
2361                         // Hook that allows last minute changes to the output page, e.g.
2362                         // adding of CSS or Javascript by extensions.
2363                         Hooks::run( 'BeforePageDisplay', [ &$this, &$sk ] );
2364
2365                         try {
2366                                 $sk->outputPage();
2367                         } catch ( Exception $e ) {
2368                                 ob_end_clean(); // bug T129657
2369                                 throw $e;
2370                         }
2371                 }
2372
2373                 try {
2374                         // This hook allows last minute changes to final overall output by modifying output buffer
2375                         Hooks::run( 'AfterFinalPageOutput', [ $this ] );
2376                 } catch ( Exception $e ) {
2377                         ob_end_clean(); // bug T129657
2378                         throw $e;
2379                 }
2380
2381                 $this->sendCacheControl();
2382
2383                 if ( $return ) {
2384                         return ob_get_clean();
2385                 } else {
2386                         ob_end_flush();
2387                         return null;
2388                 }
2389         }
2390
2391         /**
2392          * Prepare this object to display an error page; disable caching and
2393          * indexing, clear the current text and redirect, set the page's title
2394          * and optionally an custom HTML title (content of the "<title>" tag).
2395          *
2396          * @param string|Message $pageTitle Will be passed directly to setPageTitle()
2397          * @param string|Message $htmlTitle Will be passed directly to setHTMLTitle();
2398          *                   optional, if not passed the "<title>" attribute will be
2399          *                   based on $pageTitle
2400          */
2401         public function prepareErrorPage( $pageTitle, $htmlTitle = false ) {
2402                 $this->setPageTitle( $pageTitle );
2403                 if ( $htmlTitle !== false ) {
2404                         $this->setHTMLTitle( $htmlTitle );
2405                 }
2406                 $this->setRobotPolicy( 'noindex,nofollow' );
2407                 $this->setArticleRelated( false );
2408                 $this->enableClientCache( false );
2409                 $this->mRedirect = '';
2410                 $this->clearSubtitle();
2411                 $this->clearHTML();
2412         }
2413
2414         /**
2415          * Output a standard error page
2416          *
2417          * showErrorPage( 'titlemsg', 'pagetextmsg' );
2418          * showErrorPage( 'titlemsg', 'pagetextmsg', [ 'param1', 'param2' ] );
2419          * showErrorPage( 'titlemsg', $messageObject );
2420          * showErrorPage( $titleMessageObject, $messageObject );
2421          *
2422          * @param string|Message $title Message key (string) for page title, or a Message object
2423          * @param string|Message $msg Message key (string) for page text, or a Message object
2424          * @param array $params Message parameters; ignored if $msg is a Message object
2425          */
2426         public function showErrorPage( $title, $msg, $params = [] ) {
2427                 if ( !$title instanceof Message ) {
2428                         $title = $this->msg( $title );
2429                 }
2430
2431                 $this->prepareErrorPage( $title );
2432
2433                 if ( $msg instanceof Message ) {
2434                         if ( $params !== [] ) {
2435                                 trigger_error( 'Argument ignored: $params. The message parameters argument '
2436                                         . 'is discarded when the $msg argument is a Message object instead of '
2437                                         . 'a string.', E_USER_NOTICE );
2438                         }
2439                         $this->addHTML( $msg->parseAsBlock() );
2440                 } else {
2441                         $this->addWikiMsgArray( $msg, $params );
2442                 }
2443
2444                 $this->returnToMain();
2445         }
2446
2447         /**
2448          * Output a standard permission error page
2449          *
2450          * @param array $errors Error message keys or [key, param...] arrays
2451          * @param string $action Action that was denied or null if unknown
2452          */
2453         public function showPermissionsErrorPage( array $errors, $action = null ) {
2454                 foreach ( $errors as $key => $error ) {
2455                         $errors[$key] = (array)$error;
2456                 }
2457
2458                 // For some action (read, edit, create and upload), display a "login to do this action"
2459                 // error if all of the following conditions are met:
2460                 // 1. the user is not logged in
2461                 // 2. the only error is insufficient permissions (i.e. no block or something else)
2462                 // 3. the error can be avoided simply by logging in
2463                 if ( in_array( $action, [ 'read', 'edit', 'createpage', 'createtalk', 'upload' ] )
2464                         && $this->getUser()->isAnon() && count( $errors ) == 1 && isset( $errors[0][0] )
2465                         && ( $errors[0][0] == 'badaccess-groups' || $errors[0][0] == 'badaccess-group0' )
2466                         && ( User::groupHasPermission( 'user', $action )
2467                         || User::groupHasPermission( 'autoconfirmed', $action ) )
2468                 ) {
2469                         $displayReturnto = null;
2470
2471                         # Due to bug 32276, if a user does not have read permissions,
2472                         # $this->getTitle() will just give Special:Badtitle, which is
2473                         # not especially useful as a returnto parameter. Use the title
2474                         # from the request instead, if there was one.
2475                         $request = $this->getRequest();
2476                         $returnto = Title::newFromText( $request->getVal( 'title', '' ) );
2477                         if ( $action == 'edit' ) {
2478                                 $msg = 'whitelistedittext';
2479                                 $displayReturnto = $returnto;
2480                         } elseif ( $action == 'createpage' || $action == 'createtalk' ) {
2481                                 $msg = 'nocreatetext';
2482                         } elseif ( $action == 'upload' ) {
2483                                 $msg = 'uploadnologintext';
2484                         } else { # Read
2485                                 $msg = 'loginreqpagetext';
2486                                 $displayReturnto = Title::newMainPage();
2487                         }
2488
2489                         $query = [];
2490
2491                         if ( $returnto ) {
2492                                 $query['returnto'] = $returnto->getPrefixedText();
2493
2494                                 if ( !$request->wasPosted() ) {
2495                                         $returntoquery = $request->getValues();
2496                                         unset( $returntoquery['title'] );
2497                                         unset( $returntoquery['returnto'] );
2498                                         unset( $returntoquery['returntoquery'] );
2499                                         $query['returntoquery'] = wfArrayToCgi( $returntoquery );
2500                                 }
2501                         }
2502                         $loginLink = Linker::linkKnown(
2503                                 SpecialPage::getTitleFor( 'Userlogin' ),
2504                                 $this->msg( 'loginreqlink' )->escaped(),
2505                                 [],
2506                                 $query
2507                         );
2508
2509                         $this->prepareErrorPage( $this->msg( 'loginreqtitle' ) );
2510                         $this->addHTML( $this->msg( $msg )->rawParams( $loginLink )->parse() );
2511
2512                         # Don't return to a page the user can't read otherwise
2513                         # we'll end up in a pointless loop
2514                         if ( $displayReturnto && $displayReturnto->userCan( 'read', $this->getUser() ) ) {
2515                                 $this->returnToMain( null, $displayReturnto );
2516                         }
2517                 } else {
2518                         $this->prepareErrorPage( $this->msg( 'permissionserrors' ) );
2519                         $this->addWikiText( $this->formatPermissionsErrorMessage( $errors, $action ) );
2520                 }
2521         }
2522
2523         /**
2524          * Display an error page indicating that a given version of MediaWiki is
2525          * required to use it
2526          *
2527          * @param mixed $version The version of MediaWiki needed to use the page
2528          */
2529         public function versionRequired( $version ) {
2530                 $this->prepareErrorPage( $this->msg( 'versionrequired', $version ) );
2531
2532                 $this->addWikiMsg( 'versionrequiredtext', $version );
2533                 $this->returnToMain();
2534         }
2535
2536         /**
2537          * Format a list of error messages
2538          *
2539          * @param array $errors Array of arrays returned by Title::getUserPermissionsErrors
2540          * @param string $action Action that was denied or null if unknown
2541          * @return string The wikitext error-messages, formatted into a list.
2542          */
2543         public function formatPermissionsErrorMessage( array $errors, $action = null ) {
2544                 if ( $action == null ) {
2545                         $text = $this->msg( 'permissionserrorstext', count( $errors ) )->plain() . "\n\n";
2546                 } else {
2547                         $action_desc = $this->msg( "action-$action" )->plain();
2548                         $text = $this->msg(
2549                                 'permissionserrorstext-withaction',
2550                                 count( $errors ),
2551                                 $action_desc
2552                         )->plain() . "\n\n";
2553                 }
2554
2555                 if ( count( $errors ) > 1 ) {
2556                         $text .= '<ul class="permissions-errors">' . "\n";
2557
2558                         foreach ( $errors as $error ) {
2559                                 $text .= '<li>';
2560                                 $text .= call_user_func_array( [ $this, 'msg' ], $error )->plain();
2561                                 $text .= "</li>\n";
2562                         }
2563                         $text .= '</ul>';
2564                 } else {
2565                         $text .= "<div class=\"permissions-errors\">\n" .
2566                                         call_user_func_array( [ $this, 'msg' ], reset( $errors ) )->plain() .
2567                                         "\n</div>";
2568                 }
2569
2570                 return $text;
2571         }
2572
2573         /**
2574          * Display a page stating that the Wiki is in read-only mode.
2575          * Should only be called after wfReadOnly() has returned true.
2576          *
2577          * Historically, this function was used to show the source of the page that the user
2578          * was trying to edit and _also_ permissions error messages. The relevant code was
2579          * moved into EditPage in 1.19 (r102024 / d83c2a431c2a) and removed here in 1.25.
2580          *
2581          * @deprecated since 1.25; throw the exception directly
2582          * @throws ReadOnlyError
2583          */
2584         public function readOnlyPage() {
2585                 if ( func_num_args() > 0 ) {
2586                         throw new MWException( __METHOD__ . ' no longer accepts arguments since 1.25.' );
2587                 }
2588
2589                 throw new ReadOnlyError;
2590         }
2591
2592         /**
2593          * Turn off regular page output and return an error response
2594          * for when rate limiting has triggered.
2595          *
2596          * @deprecated since 1.25; throw the exception directly
2597          */
2598         public function rateLimited() {
2599                 wfDeprecated( __METHOD__, '1.25' );
2600                 throw new ThrottledError;
2601         }
2602
2603         /**
2604          * Show a warning about replica DB lag
2605          *
2606          * If the lag is higher than $wgSlaveLagCritical seconds,
2607          * then the warning is a bit more obvious. If the lag is
2608          * lower than $wgSlaveLagWarning, then no warning is shown.
2609          *
2610          * @param int $lag Slave lag
2611          */
2612         public function showLagWarning( $lag ) {
2613                 $config = $this->getConfig();
2614                 if ( $lag >= $config->get( 'SlaveLagWarning' ) ) {
2615                         $lag = floor( $lag ); // floor to avoid nano seconds to display
2616                         $message = $lag < $config->get( 'SlaveLagCritical' )
2617                                 ? 'lag-warn-normal'
2618                                 : 'lag-warn-high';
2619                         $wrap = Html::rawElement( 'div', [ 'class' => "mw-{$message}" ], "\n$1\n" );
2620                         $this->wrapWikiMsg( "$wrap\n", [ $message, $this->getLanguage()->formatNum( $lag ) ] );
2621                 }
2622         }
2623
2624         public function showFatalError( $message ) {
2625                 $this->prepareErrorPage( $this->msg( 'internalerror' ) );
2626
2627                 $this->addHTML( $message );
2628         }
2629
2630         public function showUnexpectedValueError( $name, $val ) {
2631                 $this->showFatalError( $this->msg( 'unexpected', $name, $val )->text() );
2632         }
2633
2634         public function showFileCopyError( $old, $new ) {
2635                 $this->showFatalError( $this->msg( 'filecopyerror', $old, $new )->text() );
2636         }
2637
2638         public function showFileRenameError( $old, $new ) {
2639                 $this->showFatalError( $this->msg( 'filerenameerror', $old, $new )->text() );
2640         }
2641
2642         public function showFileDeleteError( $name ) {
2643                 $this->showFatalError( $this->msg( 'filedeleteerror', $name )->text() );
2644         }
2645
2646         public function showFileNotFoundError( $name ) {
2647                 $this->showFatalError( $this->msg( 'filenotfound', $name )->text() );
2648         }
2649
2650         /**
2651          * Add a "return to" link pointing to a specified title
2652          *
2653          * @param Title $title Title to link
2654          * @param array $query Query string parameters
2655          * @param string $text Text of the link (input is not escaped)
2656          * @param array $options Options array to pass to Linker
2657          */
2658         public function addReturnTo( $title, array $query = [], $text = null, $options = [] ) {
2659                 $linkRenderer = MediaWikiServices::getInstance()
2660                         ->getLinkRendererFactory()->createFromLegacyOptions( $options );
2661                 $link = $this->msg( 'returnto' )->rawParams(
2662                         $linkRenderer->makeLink( $title, $text, [], $query ) )->escaped();
2663                 $this->addHTML( "<p id=\"mw-returnto\">{$link}</p>\n" );
2664         }
2665
2666         /**
2667          * Add a "return to" link pointing to a specified title,
2668          * or the title indicated in the request, or else the main page
2669          *
2670          * @param mixed $unused
2671          * @param Title|string $returnto Title or String to return to
2672          * @param string $returntoquery Query string for the return to link
2673          */
2674         public function returnToMain( $unused = null, $returnto = null, $returntoquery = null ) {
2675                 if ( $returnto == null ) {
2676                         $returnto = $this->getRequest()->getText( 'returnto' );
2677                 }
2678
2679                 if ( $returntoquery == null ) {
2680                         $returntoquery = $this->getRequest()->getText( 'returntoquery' );
2681                 }
2682
2683                 if ( $returnto === '' ) {
2684                         $returnto = Title::newMainPage();
2685                 }
2686
2687                 if ( is_object( $returnto ) ) {
2688                         $titleObj = $returnto;
2689                 } else {
2690                         $titleObj = Title::newFromText( $returnto );
2691                 }
2692                 if ( !is_object( $titleObj ) ) {
2693                         $titleObj = Title::newMainPage();
2694                 }
2695
2696                 $this->addReturnTo( $titleObj, wfCgiToArray( $returntoquery ) );
2697         }
2698
2699         private function getRlClientContext() {
2700                 if ( !$this->rlClientContext ) {
2701                         $query = ResourceLoader::makeLoaderQuery(
2702                                 [], // modules; not relevant
2703                                 $this->getLanguage()->getCode(),
2704                                 $this->getSkin()->getSkinName(),
2705                                 $this->getUser()->isLoggedIn() ? $this->getUser()->getName() : null,
2706                                 null, // version; not relevant
2707                                 ResourceLoader::inDebugMode(),
2708                                 null, // only; not relevant
2709                                 $this->isPrintable(),
2710                                 $this->getRequest()->getBool( 'handheld' )
2711                         );
2712                         $this->rlClientContext = new ResourceLoaderContext(
2713                                 $this->getResourceLoader(),
2714                                 new FauxRequest( $query )
2715                         );
2716                 }
2717                 return $this->rlClientContext;
2718         }
2719
2720         /**
2721          * Call this to freeze the module queue and JS config and create a formatter.
2722          *
2723          * Depending on the Skin, this may get lazy-initialised in either headElement() or
2724          * getBottomScripts(). See SkinTemplate::prepareQuickTemplate(). Calling this too early may
2725          * cause unexpected side-effects since disallowUserJs() may be called at any time to change
2726          * the module filters retroactively. Skins and extension hooks may also add modules until very
2727          * late in the request lifecycle.
2728          *
2729          * @return ResourceLoaderClientHtml
2730          */
2731         public function getRlClient() {
2732                 if ( !$this->rlClient ) {
2733                         $context = $this->getRlClientContext();
2734                         $rl = $this->getResourceLoader();
2735                         $this->addModules( [
2736                                 'user.options',
2737                                 'user.tokens',
2738                         ] );
2739                         $this->addModuleStyles( [
2740                                 'site.styles',
2741                                 'noscript',
2742                                 'user.styles',
2743                                 'user.cssprefs',
2744                         ] );
2745                         $this->getSkin()->setupSkinUserCss( $this );
2746
2747                         // Prepare exempt modules for buildExemptModules()
2748                         $exemptGroups = [ 'site' => [], 'noscript' => [], 'private' => [], 'user' => [] ];
2749                         $exemptStates = [];
2750                         $moduleStyles = $this->getModuleStyles( /*filter*/ true );
2751
2752                         // Preload getTitleInfo for isKnownEmpty calls below and in ResourceLoaderClientHtml
2753                         // Separate user-specific batch for improved cache-hit ratio.
2754                         $userBatch = [ 'user.styles', 'user' ];
2755                         $siteBatch = array_diff( $moduleStyles, $userBatch );
2756                         $dbr = wfGetDB( DB_REPLICA );
2757                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $siteBatch );
2758                         ResourceLoaderWikiModule::preloadTitleInfo( $context, $dbr, $userBatch );
2759
2760                         // Filter out modules handled by buildExemptModules()
2761                         $moduleStyles = array_filter( $moduleStyles,
2762                                 function ( $name ) use ( $rl, $context, &$exemptGroups, &$exemptStates ) {
2763                                         $module = $rl->getModule( $name );
2764                                         if ( $module ) {
2765                                                 if ( $name === 'user.styles' && $this->isUserCssPreview() ) {
2766                                                         $exemptStates[$name] = 'ready';
2767                                                         // Special case in buildExemptModules()
2768                                                         return false;
2769                                                 }
2770                                                 $group = $module->getGroup();
2771                                                 if ( isset( $exemptGroups[$group] ) ) {
2772                                                         $exemptStates[$name] = 'ready';
2773                                                         if ( !$module->isKnownEmpty( $context ) ) {
2774                                                                 // E.g. Don't output empty <styles>
2775                                                                 $exemptGroups[$group][] = $name;
2776                                                         }
2777                                                         return false;
2778                                                 }
2779                                         }
2780                                         return true;
2781                                 }
2782                         );
2783                         $this->rlExemptStyleModules = $exemptGroups;
2784
2785                         $isUserModuleFiltered = !$this->filterModules( [ 'user' ] );
2786                         // If this page filters out 'user', makeResourceLoaderLink will drop it.
2787                         // Avoid indefinite "loading" state or untrue "ready" state (T145368).
2788                         if ( !$isUserModuleFiltered ) {
2789                                 // Manually handled by getBottomScripts()
2790                                 $userModule = $rl->getModule( 'user' );
2791                                 $userState = $userModule->isKnownEmpty( $context ) && !$this->isUserJsPreview()
2792                                         ? 'ready'
2793                                         : 'loading';
2794                                 $this->rlUserModuleState = $exemptStates['user'] = $userState;
2795                         }
2796
2797                         $rlClient = new ResourceLoaderClientHtml( $context, $this->getTarget() );
2798                         $rlClient->setConfig( $this->getJSVars() );
2799                         $rlClient->setModules( $this->getModules( /*filter*/ true ) );
2800                         $rlClient->setModuleStyles( $moduleStyles );
2801                         $rlClient->setModuleScripts( $this->getModuleScripts( /*filter*/ true ) );
2802                         $rlClient->setExemptStates( $exemptStates );
2803                         $this->rlClient = $rlClient;
2804                 }
2805                 return $this->rlClient;
2806         }
2807
2808         /**
2809          * @param Skin $sk The given Skin
2810          * @param bool $includeStyle Unused
2811          * @return string The doctype, opening "<html>", and head element.
2812          */
2813         public function headElement( Skin $sk, $includeStyle = true ) {
2814                 global $wgContLang;
2815
2816                 $userdir = $this->getLanguage()->getDir();
2817                 $sitedir = $wgContLang->getDir();
2818
2819                 $pieces = [];
2820                 $pieces[] = Html::htmlHeader( Sanitizer::mergeAttributes(
2821                         $this->getRlClient()->getDocumentAttributes(),
2822                         $sk->getHtmlElementAttributes()
2823                 ) );
2824                 $pieces[] = Html::openElement( 'head' );
2825
2826                 if ( $this->getHTMLTitle() == '' ) {
2827                         $this->setHTMLTitle( $this->msg( 'pagetitle', $this->getPageTitle() )->inContentLanguage() );
2828                 }
2829
2830                 if ( !Html::isXmlMimeType( $this->getConfig()->get( 'MimeType' ) ) ) {
2831                         // Add <meta charset="UTF-8">
2832                         // This should be before <title> since it defines the charset used by
2833                         // text including the text inside <title>.
2834                         // The spec recommends defining XHTML5's charset using the XML declaration
2835                         // instead of meta.
2836                         // Our XML declaration is output by Html::htmlHeader.
2837                         // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-type
2838                         // https://html.spec.whatwg.org/multipage/semantics.html#charset
2839                         $pieces[] = Html::element( 'meta', [ 'charset' => 'UTF-8' ] );
2840                 }
2841
2842                 $pieces[] = Html::element( 'title', null, $this->getHTMLTitle() );
2843                 $pieces[] = $this->getRlClient()->getHeadHtml();
2844                 $pieces[] = $this->buildExemptModules();
2845                 $pieces = array_merge( $pieces, array_values( $this->getHeadLinksArray() ) );
2846                 $pieces = array_merge( $pieces, array_values( $this->mHeadItems ) );
2847                 $pieces[] = Html::closeElement( 'head' );
2848
2849                 $bodyClasses = [];
2850                 $bodyClasses[] = 'mediawiki';
2851
2852                 # Classes for LTR/RTL directionality support
2853                 $bodyClasses[] = $userdir;
2854                 $bodyClasses[] = "sitedir-$sitedir";
2855
2856                 if ( $this->getLanguage()->capitalizeAllNouns() ) {
2857                         # A <body> class is probably not the best way to do this . . .
2858                         $bodyClasses[] = 'capitalize-all-nouns';
2859                 }
2860
2861                 // Parser feature migration class
2862                 // The idea is that this will eventually be removed, after the wikitext
2863                 // which requires it is cleaned up.
2864                 $bodyClasses[] = 'mw-hide-empty-elt';
2865
2866                 $bodyClasses[] = $sk->getPageClasses( $this->getTitle() );
2867                 $bodyClasses[] = 'skin-' . Sanitizer::escapeClass( $sk->getSkinName() );
2868                 $bodyClasses[] =
2869                         'action-' . Sanitizer::escapeClass( Action::getActionName( $this->getContext() ) );
2870
2871                 $bodyAttrs = [];
2872                 // While the implode() is not strictly needed, it's used for backwards compatibility
2873                 // (this used to be built as a string and hooks likely still expect that).
2874                 $bodyAttrs['class'] = implode( ' ', $bodyClasses );
2875
2876                 // Allow skins and extensions to add body attributes they need
2877                 $sk->addToBodyAttributes( $this, $bodyAttrs );
2878                 Hooks::run( 'OutputPageBodyAttributes', [ $this, $sk, &$bodyAttrs ] );
2879
2880                 $pieces[] = Html::openElement( 'body', $bodyAttrs );
2881
2882                 return self::combineWrappedStrings( $pieces );
2883         }
2884
2885         /**
2886          * Get a ResourceLoader object associated with this OutputPage
2887          *
2888          * @return ResourceLoader
2889          */
2890         public function getResourceLoader() {
2891                 if ( is_null( $this->mResourceLoader ) ) {
2892                         $this->mResourceLoader = new ResourceLoader(
2893                                 $this->getConfig(),
2894                                 LoggerFactory::getInstance( 'resourceloader' )
2895                         );
2896                 }
2897                 return $this->mResourceLoader;
2898         }
2899
2900         /**
2901          * Explicily load or embed modules on a page.
2902          *
2903          * @param array|string $modules One or more module names
2904          * @param string $only ResourceLoaderModule TYPE_ class constant
2905          * @param array $extraQuery [optional] Array with extra query parameters for the request
2906          * @return string|WrappedStringList HTML
2907          */
2908         public function makeResourceLoaderLink( $modules, $only, array $extraQuery = [] ) {
2909                 // Apply 'target' and 'origin' filters
2910                 $modules = $this->filterModules( (array)$modules, null, $only );
2911
2912                 return ResourceLoaderClientHtml::makeLoad(
2913                         $this->getRlClientContext(),
2914                         $modules,
2915                         $only,
2916                         $extraQuery
2917                 );
2918         }
2919
2920         /**
2921          * Combine WrappedString chunks and filter out empty ones
2922          *
2923          * @param array $chunks
2924          * @return string|WrappedStringList HTML
2925          */
2926         protected static function combineWrappedStrings( array $chunks ) {
2927                 // Filter out empty values
2928                 $chunks = array_filter( $chunks, 'strlen' );
2929                 return WrappedString::join( "\n", $chunks );
2930         }
2931
2932         private function isUserJsPreview() {
2933                 return $this->getConfig()->get( 'AllowUserJs' )
2934                         && $this->getTitle()
2935                         && $this->getTitle()->isJsSubpage()
2936                         && $this->userCanPreview();
2937         }
2938
2939         private function isUserCssPreview() {
2940                 return $this->getConfig()->get( 'AllowUserCss' )
2941                         && $this->getTitle()
2942                         && $this->getTitle()->isCssSubpage()
2943                         && $this->userCanPreview();
2944         }
2945
2946         /**
2947          * JS stuff to put at the bottom of the `<body>`. These are modules with position 'bottom',
2948          * legacy scripts ($this->mScripts), and user JS.
2949          *
2950          * @return string|WrappedStringList HTML
2951          */
2952         public function getBottomScripts() {
2953                 $chunks = [];
2954                 $chunks[] = $this->getRlClient()->getBodyHtml();
2955
2956                 // Legacy non-ResourceLoader scripts
2957                 $chunks[] = $this->mScripts;
2958
2959                 // Exempt 'user' module
2960                 // - May need excludepages for live preview. (T28283)
2961                 // - Must use TYPE_COMBINED so its response is handled by mw.loader.implement() which
2962                 //   ensures execution is scheduled after the "site" module.
2963                 // - Don't load if module state is already resolved as "ready".
2964                 if ( $this->rlUserModuleState === 'loading' ) {
2965                         if ( $this->isUserJsPreview() ) {
2966                                 $chunks[] = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_COMBINED,
2967                                         [ 'excludepage' => $this->getTitle()->getPrefixedDBkey() ]
2968                                 );
2969                                 $chunks[] = ResourceLoader::makeInlineScript(
2970                                         Xml::encodeJsCall( 'mw.loader.using', [
2971                                                 [ 'user', 'site' ],
2972                                                 new XmlJsCode(
2973                                                         'function () {'
2974                                                                 . Xml::encodeJsCall( '$.globalEval', [
2975                                                                         $this->getRequest()->getText( 'wpTextbox1' )
2976                                                                 ] )
2977                                                                 . '}'
2978                                                 )
2979                                         ] )
2980                                 );
2981                                 // FIXME: If the user is previewing, say, ./vector.js, his ./common.js will be loaded
2982                                 // asynchronously and may arrive *after* the inline script here. So the previewed code
2983                                 // may execute before ./common.js runs. Normally, ./common.js runs before ./vector.js.
2984                                 // Similarly, when previewing ./common.js and the user module does arrive first,
2985                                 // it will arrive without common.js and the inline script runs after.
2986                                 // Thus running common after the excluded subpage.
2987                         } else {
2988                                 // Load normally
2989                                 $chunks[] = $this->makeResourceLoaderLink( 'user', ResourceLoaderModule::TYPE_COMBINED );
2990                         }
2991                 }
2992
2993                 return self::combineWrappedStrings( $chunks );
2994         }
2995
2996         /**
2997          * Get the javascript config vars to include on this page
2998          *
2999          * @return array Array of javascript config vars
3000          * @since 1.23
3001          */
3002         public function getJsConfigVars() {
3003                 return $this->mJsConfigVars;
3004         }
3005
3006         /**
3007          * Add one or more variables to be set in mw.config in JavaScript
3008          *
3009          * @param string|array $keys Key or array of key/value pairs
3010          * @param mixed $value [optional] Value of the configuration variable
3011          */
3012         public function addJsConfigVars( $keys, $value = null ) {
3013                 if ( is_array( $keys ) ) {
3014                         foreach ( $keys as $key => $value ) {
3015                                 $this->mJsConfigVars[$key] = $value;
3016                         }
3017                         return;
3018                 }
3019
3020                 $this->mJsConfigVars[$keys] = $value;
3021         }
3022
3023         /**
3024          * Get an array containing the variables to be set in mw.config in JavaScript.
3025          *
3026          * Do not add things here which can be evaluated in ResourceLoaderStartUpModule
3027          * - in other words, page-independent/site-wide variables (without state).
3028          * You will only be adding bloat to the html page and causing page caches to
3029          * have to be purged on configuration changes.
3030          * @return array
3031          */
3032         public function getJSVars() {
3033                 global $wgContLang;
3034
3035                 $curRevisionId = 0;
3036                 $articleId = 0;
3037                 $canonicalSpecialPageName = false; # bug 21115
3038
3039                 $title = $this->getTitle();
3040                 $ns = $title->getNamespace();
3041                 $canonicalNamespace = MWNamespace::exists( $ns )
3042                         ? MWNamespace::getCanonicalName( $ns )
3043                         : $title->getNsText();
3044
3045                 $sk = $this->getSkin();
3046                 // Get the relevant title so that AJAX features can use the correct page name
3047                 // when making API requests from certain special pages (bug 34972).
3048                 $relevantTitle = $sk->getRelevantTitle();
3049                 $relevantUser = $sk->getRelevantUser();
3050
3051                 if ( $ns == NS_SPECIAL ) {
3052                         list( $canonicalSpecialPageName, /*...*/ ) =
3053                                 SpecialPageFactory::resolveAlias( $title->getDBkey() );
3054                 } elseif ( $this->canUseWikiPage() ) {
3055                         $wikiPage = $this->getWikiPage();
3056                         $curRevisionId = $wikiPage->getLatest();
3057                         $articleId = $wikiPage->getId();
3058                 }
3059
3060                 $lang = $title->getPageViewLanguage();
3061
3062                 // Pre-process information
3063                 $separatorTransTable = $lang->separatorTransformTable();
3064                 $separatorTransTable = $separatorTransTable ? $separatorTransTable : [];
3065                 $compactSeparatorTransTable = [
3066                         implode( "\t", array_keys( $separatorTransTable ) ),
3067                         implode( "\t", $separatorTransTable ),
3068                 ];
3069                 $digitTransTable = $lang->digitTransformTable();
3070                 $digitTransTable = $digitTransTable ? $digitTransTable : [];
3071                 $compactDigitTransTable = [
3072                         implode( "\t", array_keys( $digitTransTable ) ),
3073                         implode( "\t", $digitTransTable ),
3074                 ];
3075
3076                 $user = $this->getUser();
3077
3078                 $vars = [
3079                         'wgCanonicalNamespace' => $canonicalNamespace,
3080                         'wgCanonicalSpecialPageName' => $canonicalSpecialPageName,
3081                         'wgNamespaceNumber' => $title->getNamespace(),
3082                         'wgPageName' => $title->getPrefixedDBkey(),
3083                         'wgTitle' => $title->getText(),
3084                         'wgCurRevisionId' => $curRevisionId,
3085                         'wgRevisionId' => (int)$this->getRevisionId(),
3086                         'wgArticleId' => $articleId,
3087                         'wgIsArticle' => $this->isArticle(),
3088                         'wgIsRedirect' => $title->isRedirect(),
3089                         'wgAction' => Action::getActionName( $this->getContext() ),
3090                         'wgUserName' => $user->isAnon() ? null : $user->getName(),
3091                         'wgUserGroups' => $user->getEffectiveGroups(),
3092                         'wgCategories' => $this->getCategories(),
3093                         'wgBreakFrames' => $this->getFrameOptions() == 'DENY',
3094                         'wgPageContentLanguage' => $lang->getCode(),
3095                         'wgPageContentModel' => $title->getContentModel(),
3096                         'wgSeparatorTransformTable' => $compactSeparatorTransTable,
3097                         'wgDigitTransformTable' => $compactDigitTransTable,
3098                         'wgDefaultDateFormat' => $lang->getDefaultDateFormat(),
3099                         'wgMonthNames' => $lang->getMonthNamesArray(),
3100                         'wgMonthNamesShort' => $lang->getMonthAbbreviationsArray(),
3101                         'wgRelevantPageName' => $relevantTitle->getPrefixedDBkey(),
3102                         'wgRelevantArticleId' => $relevantTitle->getArticleID(),
3103                         'wgRequestId' => WebRequest::getRequestId(),
3104                 ];
3105
3106                 if ( $user->isLoggedIn() ) {
3107                         $vars['wgUserId'] = $user->getId();
3108                         $vars['wgUserEditCount'] = $user->getEditCount();
3109                         $userReg = $user->getRegistration();
3110                         $vars['wgUserRegistration'] = $userReg ? wfTimestamp( TS_UNIX, $userReg ) * 1000 : null;
3111                         // Get the revision ID of the oldest new message on the user's talk
3112                         // page. This can be used for constructing new message alerts on
3113                         // the client side.
3114                         $vars['wgUserNewMsgRevisionId'] = $user->getNewMessageRevisionId();
3115                 }
3116
3117                 if ( $wgContLang->hasVariants() ) {
3118                         $vars['wgUserVariant'] = $wgContLang->getPreferredVariant();
3119                 }
3120                 // Same test as SkinTemplate
3121                 $vars['wgIsProbablyEditable'] = $title->quickUserCan( 'edit', $user )
3122                         && ( $title->exists() || $title->quickUserCan( 'create', $user ) );
3123
3124                 foreach ( $title->getRestrictionTypes() as $type ) {
3125                         $vars['wgRestriction' . ucfirst( $type )] = $title->getRestrictions( $type );
3126                 }
3127
3128                 if ( $title->isMainPage() ) {
3129                         $vars['wgIsMainPage'] = true;
3130                 }
3131
3132                 if ( $this->mRedirectedFrom ) {
3133                         $vars['wgRedirectedFrom'] = $this->mRedirectedFrom->getPrefixedDBkey();
3134                 }
3135
3136                 if ( $relevantUser ) {
3137                         $vars['wgRelevantUserName'] = $relevantUser->getName();
3138                 }
3139
3140                 // Allow extensions to add their custom variables to the mw.config map.
3141                 // Use the 'ResourceLoaderGetConfigVars' hook if the variable is not
3142                 // page-dependant but site-wide (without state).
3143                 // Alternatively, you may want to use OutputPage->addJsConfigVars() instead.
3144                 Hooks::run( 'MakeGlobalVariablesScript', [ &$vars, $this ] );
3145
3146                 // Merge in variables from addJsConfigVars last
3147                 return array_merge( $vars, $this->getJsConfigVars() );
3148         }
3149
3150         /**
3151          * To make it harder for someone to slip a user a fake
3152          * user-JavaScript or user-CSS preview, a random token
3153          * is associated with the login session. If it's not
3154          * passed back with the preview request, we won't render
3155          * the code.
3156          *
3157          * @return bool
3158          */
3159         public function userCanPreview() {
3160                 $request = $this->getRequest();
3161                 if (
3162                         $request->getVal( 'action' ) !== 'submit' ||
3163                         !$request->getCheck( 'wpPreview' ) ||
3164                         !$request->wasPosted()
3165                 ) {
3166                         return false;
3167                 }
3168
3169                 $user = $this->getUser();
3170
3171                 if ( !$user->isLoggedIn() ) {
3172                         // Anons have predictable edit tokens
3173                         return false;
3174                 }
3175                 if ( !$user->matchEditToken( $request->getVal( 'wpEditToken' ) ) ) {
3176                         return false;
3177                 }
3178
3179                 $title = $this->getTitle();
3180                 if ( !$title->isJsSubpage() && !$title->isCssSubpage() ) {
3181                         return false;
3182                 }
3183                 if ( !$title->isSubpageOf( $user->getUserPage() ) ) {
3184                         // Don't execute another user's CSS or JS on preview (T85855)
3185                         return false;
3186                 }
3187
3188                 $errors = $title->getUserPermissionsErrors( 'edit', $user );
3189                 if ( count( $errors ) !== 0 ) {
3190                         return false;
3191                 }
3192
3193                 return true;
3194         }
3195
3196         /**
3197          * @return array Array in format "link name or number => 'link html'".
3198          */
3199         public function getHeadLinksArray() {
3200                 global $wgVersion;
3201
3202                 $tags = [];
3203                 $config = $this->getConfig();
3204
3205                 $canonicalUrl = $this->mCanonicalUrl;
3206
3207                 $tags['meta-generator'] = Html::element( 'meta', [
3208                         'name' => 'generator',
3209                         'content' => "MediaWiki $wgVersion",
3210                 ] );
3211
3212                 if ( $config->get( 'ReferrerPolicy' ) !== false ) {
3213                         $tags['meta-referrer'] = Html::element( 'meta', [
3214                                 'name' => 'referrer',
3215                                 'content' => $config->get( 'ReferrerPolicy' )
3216                         ] );
3217                 }
3218
3219                 $p = "{$this->mIndexPolicy},{$this->mFollowPolicy}";
3220                 if ( $p !== 'index,follow' ) {
3221                         // http://www.robotstxt.org/wc/meta-user.html
3222                         // Only show if it's different from the default robots policy
3223                         $tags['meta-robots'] = Html::element( 'meta', [
3224                                 'name' => 'robots',
3225                                 'content' => $p,
3226                         ] );
3227                 }
3228
3229                 foreach ( $this->mMetatags as $tag ) {
3230                         if ( 0 == strcasecmp( 'http:', substr( $tag[0], 0, 5 ) ) ) {
3231                                 $a = 'http-equiv';
3232                                 $tag[0] = substr( $tag[0], 5 );
3233                         } else {
3234                                 $a = 'name';
3235                         }
3236                         $tagName = "meta-{$tag[0]}";
3237                         if ( isset( $tags[$tagName] ) ) {
3238                                 $tagName .= $tag[1];
3239                         }
3240                         $tags[$tagName] = Html::element( 'meta',
3241                                 [
3242                                         $a => $tag[0],
3243                                         'content' => $tag[1]
3244                                 ]
3245                         );
3246                 }
3247
3248                 foreach ( $this->mLinktags as $tag ) {
3249                         $tags[] = Html::element( 'link', $tag );
3250                 }
3251
3252                 # Universal edit button
3253                 if ( $config->get( 'UniversalEditButton' ) && $this->isArticleRelated() ) {
3254                         $user = $this->getUser();
3255                         if ( $this->getTitle()->quickUserCan( 'edit', $user )
3256                                 && ( $this->getTitle()->exists() ||
3257                                         $this->getTitle()->quickUserCan( 'create', $user ) )
3258                         ) {
3259                                 // Original UniversalEditButton
3260                                 $msg = $this->msg( 'edit' )->text();
3261                                 $tags['universal-edit-button'] = Html::element( 'link', [
3262                                         'rel' => 'alternate',
3263                                         'type' => 'application/x-wiki',
3264                                         'title' => $msg,
3265                                         'href' => $this->getTitle()->getEditURL(),
3266                                 ] );
3267                                 // Alternate edit link
3268                                 $tags['alternative-edit'] = Html::element( 'link', [
3269                                         'rel' => 'edit',
3270                                         'title' => $msg,
3271                                         'href' => $this->getTitle()->getEditURL(),
3272                                 ] );
3273                         }
3274                 }
3275
3276                 # Generally the order of the favicon and apple-touch-icon links
3277                 # should not matter, but Konqueror (3.5.9 at least) incorrectly
3278                 # uses whichever one appears later in the HTML source. Make sure
3279                 # apple-touch-icon is specified first to avoid this.
3280                 if ( $config->get( 'AppleTouchIcon' ) !== false ) {
3281                         $tags['apple-touch-icon'] = Html::element( 'link', [
3282                                 'rel' => 'apple-touch-icon',
3283                                 'href' => $config->get( 'AppleTouchIcon' )
3284                         ] );
3285                 }
3286
3287                 if ( $config->get( 'Favicon' ) !== false ) {
3288                         $tags['favicon'] = Html::element( 'link', [
3289                                 'rel' => 'shortcut icon',
3290                                 'href' => $config->get( 'Favicon' )
3291                         ] );
3292                 }
3293
3294                 # OpenSearch description link
3295                 $tags['opensearch'] = Html::element( 'link', [
3296                         'rel' => 'search',
3297                         'type' => 'application/opensearchdescription+xml',
3298                         'href' => wfScript( 'opensearch_desc' ),
3299                         'title' => $this->msg( 'opensearch-desc' )->inContentLanguage()->text(),
3300                 ] );
3301
3302                 if ( $config->get( 'EnableAPI' ) ) {
3303                         # Real Simple Discovery link, provides auto-discovery information
3304                         # for the MediaWiki API (and potentially additional custom API
3305                         # support such as WordPress or Twitter-compatible APIs for a
3306                         # blogging extension, etc)
3307                         $tags['rsd'] = Html::element( 'link', [
3308                                 'rel' => 'EditURI',
3309                                 'type' => 'application/rsd+xml',
3310                                 // Output a protocol-relative URL here if $wgServer is protocol-relative.
3311                                 // Whether RSD accepts relative or protocol-relative URLs is completely
3312                                 // undocumented, though.
3313                                 'href' => wfExpandUrl( wfAppendQuery(
3314                                         wfScript( 'api' ),
3315                                         [ 'action' => 'rsd' ] ),
3316                                         PROTO_RELATIVE
3317                                 ),
3318                         ] );
3319                 }
3320
3321                 # Language variants
3322                 if ( !$config->get( 'DisableLangConversion' ) ) {
3323                         $lang = $this->getTitle()->getPageLanguage();
3324                         if ( $lang->hasVariants() ) {
3325                                 $variants = $lang->getVariants();
3326                                 foreach ( $variants as $variant ) {
3327                                         $tags["variant-$variant"] = Html::element( 'link', [
3328                                                 'rel' => 'alternate',
3329                                                 'hreflang' => wfBCP47( $variant ),
3330                                                 'href' => $this->getTitle()->getLocalURL(
3331                                                         [ 'variant' => $variant ] )
3332                                                 ]
3333                                         );
3334                                 }
3335                                 # x-default link per https://support.google.com/webmasters/answer/189077?hl=en
3336                                 $tags["variant-x-default"] = Html::element( 'link', [
3337                                         'rel' => 'alternate',
3338                                         'hreflang' => 'x-default',
3339                                         'href' => $this->getTitle()->getLocalURL() ] );
3340                         }
3341                 }
3342
3343                 # Copyright
3344                 if ( $this->copyrightUrl !== null ) {
3345                         $copyright = $this->copyrightUrl;
3346                 } else {
3347                         $copyright = '';
3348                         if ( $config->get( 'RightsPage' ) ) {
3349                                 $copy = Title::newFromText( $config->get( 'RightsPage' ) );
3350
3351                                 if ( $copy ) {
3352                                         $copyright = $copy->getLocalURL();
3353                                 }
3354                         }
3355
3356                         if ( !$copyright && $config->get( 'RightsUrl' ) ) {
3357                                 $copyright = $config->get( 'RightsUrl' );
3358                         }
3359                 }
3360
3361                 if ( $copyright ) {
3362                         $tags['copyright'] = Html::element( 'link', [
3363                                 'rel' => 'copyright',
3364                                 'href' => $copyright ]
3365                         );
3366                 }
3367
3368                 # Feeds
3369                 if ( $config->get( 'Feed' ) ) {
3370                         $feedLinks = [];
3371
3372                         foreach ( $this->getSyndicationLinks() as $format => $link ) {
3373                                 # Use the page name for the title.  In principle, this could
3374                                 # lead to issues with having the same name for different feeds
3375                                 # corresponding to the same page, but we can't avoid that at
3376                                 # this low a level.
3377
3378                                 $feedLinks[] = $this->feedLink(
3379                                         $format,
3380                                         $link,
3381                                         # Used messages: 'page-rss-feed' and 'page-atom-feed' (for an easier grep)
3382                                         $this->msg(
3383                                                 "page-{$format}-feed", $this->getTitle()->getPrefixedText()
3384                                         )->text()
3385                                 );
3386                         }
3387
3388                         # Recent changes feed should appear on every page (except recentchanges,
3389                         # that would be redundant). Put it after the per-page feed to avoid
3390                         # changing existing behavior. It's still available, probably via a
3391                         # menu in your browser. Some sites might have a different feed they'd
3392                         # like to promote instead of the RC feed (maybe like a "Recent New Articles"
3393                         # or "Breaking news" one). For this, we see if $wgOverrideSiteFeed is defined.
3394                         # If so, use it instead.
3395                         $sitename = $config->get( 'Sitename' );
3396                         if ( $config->get( 'OverrideSiteFeed' ) ) {
3397                                 foreach ( $config->get( 'OverrideSiteFeed' ) as $type => $feedUrl ) {
3398                                         // Note, this->feedLink escapes the url.
3399                                         $feedLinks[] = $this->feedLink(
3400                                                 $type,
3401                                                 $feedUrl,
3402                                                 $this->msg( "site-{$type}-feed", $sitename )->text()
3403                                         );
3404                                 }
3405                         } elseif ( !$this->getTitle()->isSpecial( 'Recentchanges' ) ) {
3406                                 $rctitle = SpecialPage::getTitleFor( 'Recentchanges' );
3407                                 foreach ( $config->get( 'AdvertisedFeedTypes' ) as $format ) {
3408                                         $feedLinks[] = $this->feedLink(
3409                                                 $format,
3410                                                 $rctitle->getLocalURL( [ 'feed' => $format ] ),
3411                                                 # For grep: 'site-rss-feed', 'site-atom-feed'
3412                                                 $this->msg( "site-{$format}-feed", $sitename )->text()
3413                                         );
3414                                 }
3415                         }
3416
3417                         # Allow extensions to change the list pf feeds. This hook is primarily for changing,
3418                         # manipulating or removing existing feed tags. If you want to add new feeds, you should
3419                         # use OutputPage::addFeedLink() instead.
3420                         Hooks::run( 'AfterBuildFeedLinks', [ &$feedLinks ] );
3421
3422                         $tags += $feedLinks;
3423                 }
3424
3425                 # Canonical URL
3426                 if ( $config->get( 'EnableCanonicalServerLink' ) ) {
3427                         if ( $canonicalUrl !== false ) {
3428                                 $canonicalUrl = wfExpandUrl( $canonicalUrl, PROTO_CANONICAL );
3429                         } else {
3430                                 if ( $this->isArticleRelated() ) {
3431                                         // This affects all requests where "setArticleRelated" is true. This is
3432                                         // typically all requests that show content (query title, curid, oldid, diff),
3433                                         // and all wikipage actions (edit, delete, purge, info, history etc.).
3434                                         // It does not apply to File pages and Special pages.
3435                                         // 'history' and 'info' actions address page metadata rather than the page
3436                                         // content itself, so they may not be canonicalized to the view page url.
3437                                         // TODO: this ought to be better encapsulated in the Action class.
3438                                         $action = Action::getActionName( $this->getContext() );
3439                                         if ( in_array( $action, [ 'history', 'info' ] ) ) {
3440                                                 $query = "action={$action}";
3441                                         } else {
3442                                                 $query = '';
3443                                         }
3444                                         $canonicalUrl = $this->getTitle()->getCanonicalURL( $query );
3445                                 } else {
3446                                         $reqUrl = $this->getRequest()->getRequestURL();
3447                                         $canonicalUrl = wfExpandUrl( $reqUrl, PROTO_CANONICAL );
3448                                 }
3449                         }
3450                 }
3451                 if ( $canonicalUrl !== false ) {
3452                         $tags[] = Html::element( 'link', [
3453                                 'rel' => 'canonical',
3454                                 'href' => $canonicalUrl
3455                         ] );
3456                 }
3457
3458                 return $tags;
3459         }
3460
3461         /**
3462          * @return string HTML tag links to be put in the header.
3463          * @deprecated since 1.24 Use OutputPage::headElement or if you have to,
3464          *   OutputPage::getHeadLinksArray directly.
3465          */
3466         public function getHeadLinks() {
3467                 wfDeprecated( __METHOD__, '1.24' );
3468                 return implode( "\n", $this->getHeadLinksArray() );
3469         }
3470
3471         /**
3472          * Generate a "<link rel/>" for a feed.
3473          *
3474          * @param string $type Feed type
3475          * @param string $url URL to the feed
3476          * @param string $text Value of the "title" attribute
3477          * @return string HTML fragment
3478          */
3479         private function feedLink( $type, $url, $text ) {
3480                 return Html::element( 'link', [
3481                         'rel' => 'alternate',
3482                         'type' => "application/$type+xml",
3483                         'title' => $text,
3484                         'href' => $url ]
3485                 );
3486         }
3487
3488         /**
3489          * Add a local or specified stylesheet, with the given media options.
3490          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3491          *
3492          * @param string $style URL to the file
3493          * @param string $media To specify a media type, 'screen', 'printable', 'handheld' or any.
3494          * @param string $condition For IE conditional comments, specifying an IE version
3495          * @param string $dir Set to 'rtl' or 'ltr' for direction-specific sheets
3496          */
3497         public function addStyle( $style, $media = '', $condition = '', $dir = '' ) {
3498                 $options = [];
3499                 if ( $media ) {
3500                         $options['media'] = $media;
3501                 }
3502                 if ( $condition ) {
3503                         $options['condition'] = $condition;
3504                 }
3505                 if ( $dir ) {
3506                         $options['dir'] = $dir;
3507                 }
3508                 $this->styles[$style] = $options;
3509         }
3510
3511         /**
3512          * Adds inline CSS styles
3513          * Internal use only. Use OutputPage::addModuleStyles() if possible.
3514          *
3515          * @param mixed $style_css Inline CSS
3516          * @param string $flip Set to 'flip' to flip the CSS if needed
3517          */
3518         public function addInlineStyle( $style_css, $flip = 'noflip' ) {
3519                 if ( $flip === 'flip' && $this->getLanguage()->isRTL() ) {
3520                         # If wanted, and the interface is right-to-left, flip the CSS
3521                         $style_css = CSSJanus::transform( $style_css, true, false );
3522                 }
3523                 $this->mInlineStyles .= Html::inlineStyle( $style_css );
3524         }
3525
3526         /**
3527          * Build exempt modules and legacy non-ResourceLoader styles.
3528          *
3529          * @return string|WrappedStringList HTML
3530          */
3531         protected function buildExemptModules() {
3532                 global $wgContLang;
3533
3534                 $resourceLoader = $this->getResourceLoader();
3535                 $chunks = [];
3536                 // Things that go after the ResourceLoaderDynamicStyles marker
3537                 $append = [];
3538
3539                 // Exempt 'user' styles module (may need 'excludepages' for live preview)
3540                 if ( $this->isUserCssPreview() ) {
3541                         $append[] = $this->makeResourceLoaderLink(
3542                                 'user.styles',
3543                                 ResourceLoaderModule::TYPE_STYLES,
3544                                 [ 'excludepage' => $this->getTitle()->getPrefixedDBkey() ]
3545                         );
3546
3547                         // Load the previewed CSS. Janus it if needed.
3548                         // User-supplied CSS is assumed to in the wiki's content language.
3549                         $previewedCSS = $this->getRequest()->getText( 'wpTextbox1' );
3550                         if ( $this->getLanguage()->getDir() !== $wgContLang->getDir() ) {
3551                                 $previewedCSS = CSSJanus::transform( $previewedCSS, true, false );
3552                         }
3553                         $append[] = Html::inlineStyle( $previewedCSS );
3554                 }
3555
3556                 // We want site, private and user styles to override dynamically added styles from
3557                 // general modules, but we want dynamically added styles to override statically added
3558                 // style modules. So the order has to be:
3559                 // - page style modules (formatted by ResourceLoaderClientHtml::getHeadHtml())
3560                 // - dynamically loaded styles (added by mw.loader before ResourceLoaderDynamicStyles)
3561                 // - ResourceLoaderDynamicStyles marker
3562                 // - site/private/user styles
3563
3564                 // Add legacy styles added through addStyle()/addInlineStyle() here
3565                 $chunks[] = implode( '', $this->buildCssLinksArray() ) . $this->mInlineStyles;
3566
3567                 $chunks[] = Html::element(
3568                         'meta',
3569                         [ 'name' => 'ResourceLoaderDynamicStyles', 'content' => '' ]
3570                 );
3571
3572                 foreach ( $this->rlExemptStyleModules as $group => $moduleNames ) {
3573                         $chunks[] = $this->makeResourceLoaderLink( $moduleNames,
3574                                 ResourceLoaderModule::TYPE_STYLES
3575                         );
3576                 }
3577
3578                 return self::combineWrappedStrings( array_merge( $chunks, $append ) );
3579         }
3580
3581         /**
3582          * @return array
3583          */
3584         public function buildCssLinksArray() {
3585                 $links = [];
3586
3587                 // Add any extension CSS
3588                 foreach ( $this->mExtStyles as $url ) {
3589                         $this->addStyle( $url );
3590                 }
3591                 $this->mExtStyles = [];
3592
3593                 foreach ( $this->styles as $file => $options ) {
3594                         $link = $this->styleLink( $file, $options );
3595                         if ( $link ) {
3596                                 $links[$file] = $link;
3597                         }
3598                 }
3599                 return $links;
3600         }
3601
3602         /**
3603          * Generate \<link\> tags for stylesheets
3604          *
3605          * @param string $style URL to the file
3606          * @param array $options Option, can contain 'condition', 'dir', 'media' keys
3607          * @return string HTML fragment
3608          */
3609         protected function styleLink( $style, array $options ) {
3610                 if ( isset( $options['dir'] ) ) {
3611                         if ( $this->getLanguage()->getDir() != $options['dir'] ) {
3612                                 return '';
3613                         }
3614                 }
3615
3616                 if ( isset( $options['media'] ) ) {
3617                         $media = self::transformCssMedia( $options['media'] );
3618                         if ( is_null( $media ) ) {
3619                                 return '';
3620                         }
3621                 } else {
3622                         $media = 'all';
3623                 }
3624
3625                 if ( substr( $style, 0, 1 ) == '/' ||
3626                         substr( $style, 0, 5 ) == 'http:' ||
3627                         substr( $style, 0, 6 ) == 'https:' ) {
3628                         $url = $style;
3629                 } else {
3630                         $config = $this->getConfig();
3631                         $url = $config->get( 'StylePath' ) . '/' . $style . '?' .
3632                                 $config->get( 'StyleVersion' );
3633                 }
3634
3635                 $link = Html::linkedStyle( $url, $media );
3636
3637                 if ( isset( $options['condition'] ) ) {
3638                         $condition = htmlspecialchars( $options['condition'] );
3639                         $link = "<!--[if $condition]>$link<![endif]-->";
3640                 }
3641                 return $link;
3642         }
3643
3644         /**
3645          * Transform path to web-accessible static resource.
3646          *
3647          * This is used to add a validation hash as query string.
3648          * This aids various behaviors:
3649          *
3650          * - Put long Cache-Control max-age headers on responses for improved
3651          *   cache performance.
3652          * - Get the correct version of a file as expected by the current page.
3653          * - Instantly get the updated version of a file after deployment.
3654          *
3655          * Avoid using this for urls included in HTML as otherwise clients may get different
3656          * versions of a resource when navigating the site depending on when the page was cached.
3657          * If changes to the url propagate, this is not a problem (e.g. if the url is in
3658          * an external stylesheet).
3659          *
3660          * @since 1.27
3661          * @param Config $config
3662          * @param string $path Path-absolute URL to file (from document root, must start with "/")
3663          * @return string URL
3664          */
3665         public static function transformResourcePath( Config $config, $path ) {
3666                 global $IP;
3667                 $remotePathPrefix = $config->get( 'ResourceBasePath' );
3668                 if ( $remotePathPrefix === '' ) {
3669                         // The configured base path is required to be empty string for
3670                         // wikis in the domain root
3671                         $remotePath = '/';
3672                 } else {
3673                         $remotePath = $remotePathPrefix;
3674                 }
3675                 if ( strpos( $path, $remotePath ) !== 0 ) {
3676                         // Path is outside wgResourceBasePath, ignore.
3677                         return $path;
3678                 }
3679                 $path = RelPath\getRelativePath( $path, $remotePath );
3680                 return self::transformFilePath( $remotePathPrefix, $IP, $path );
3681         }
3682
3683         /**
3684          * Utility method for transformResourceFilePath().
3685          *
3686          * Caller is responsible for ensuring the file exists. Emits a PHP warning otherwise.
3687          *
3688          * @since 1.27
3689          * @param string $remotePath URL path prefix that points to $localPath
3690          * @param string $localPath File directory exposed at $remotePath
3691          * @param string $file Path to target file relative to $localPath
3692          * @return string URL
3693          */
3694         public static function transformFilePath( $remotePathPrefix, $localPath, $file ) {
3695                 $hash = md5_file( "$localPath/$file" );
3696                 if ( $hash === false ) {
3697                         wfLogWarning( __METHOD__ . ": Failed to hash $localPath/$file" );
3698                         $hash = '';
3699                 }
3700                 return "$remotePathPrefix/$file?" . substr( $hash, 0, 5 );
3701         }
3702
3703         /**
3704          * Transform "media" attribute based on request parameters
3705          *
3706          * @param string $media Current value of the "media" attribute
3707          * @return string Modified value of the "media" attribute, or null to skip
3708          * this stylesheet
3709          */
3710         public static function transformCssMedia( $media ) {
3711                 global $wgRequest;
3712
3713                 // https://www.w3.org/TR/css3-mediaqueries/#syntax
3714                 $screenMediaQueryRegex = '/^(?:only\s+)?screen\b/i';
3715
3716                 // Switch in on-screen display for media testing
3717                 $switches = [
3718                         'printable' => 'print',
3719                         'handheld' => 'handheld',
3720                 ];
3721                 foreach ( $switches as $switch => $targetMedia ) {
3722                         if ( $wgRequest->getBool( $switch ) ) {
3723                                 if ( $media == $targetMedia ) {
3724                                         $media = '';
3725                                 } elseif ( preg_match( $screenMediaQueryRegex, $media ) === 1 ) {
3726                                         /* This regex will not attempt to understand a comma-separated media_query_list
3727                                          *
3728                                          * Example supported values for $media:
3729                                          * 'screen', 'only screen', 'screen and (min-width: 982px)' ),
3730                                          * Example NOT supported value for $media:
3731                                          * '3d-glasses, screen, print and resolution > 90dpi'
3732                                          *
3733                                          * If it's a print request, we never want any kind of screen stylesheets
3734                                          * If it's a handheld request (currently the only other choice with a switch),
3735                                          * we don't want simple 'screen' but we might want screen queries that
3736                                          * have a max-width or something, so we'll pass all others on and let the
3737                                          * client do the query.
3738                                          */
3739                                         if ( $targetMedia == 'print' || $media == 'screen' ) {
3740                                                 return null;
3741                                         }
3742                                 }
3743                         }
3744                 }
3745
3746                 return $media;
3747         }
3748
3749         /**
3750          * Add a wikitext-formatted message to the output.
3751          * This is equivalent to:
3752          *
3753          *    $wgOut->addWikiText( wfMessage( ... )->plain() )
3754          */
3755         public function addWikiMsg( /*...*/ ) {
3756                 $args = func_get_args();
3757                 $name = array_shift( $args );
3758                 $this->addWikiMsgArray( $name, $args );
3759         }
3760
3761         /**
3762          * Add a wikitext-formatted message to the output.
3763          * Like addWikiMsg() except the parameters are taken as an array
3764          * instead of a variable argument list.
3765          *
3766          * @param string $name
3767          * @param array $args
3768          */
3769         public function addWikiMsgArray( $name, $args ) {
3770                 $this->addHTML( $this->msg( $name, $args )->parseAsBlock() );
3771         }
3772
3773         /**
3774          * This function takes a number of message/argument specifications, wraps them in
3775          * some overall structure, and then parses the result and adds it to the output.
3776          *
3777          * In the $wrap, $1 is replaced with the first message, $2 with the second,
3778          * and so on. The subsequent arguments may be either
3779          * 1) strings, in which case they are message names, or
3780          * 2) arrays, in which case, within each array, the first element is the message
3781          *    name, and subsequent elements are the parameters to that message.
3782          *
3783          * Don't use this for messages that are not in the user's interface language.
3784          *
3785          * For example:
3786          *
3787          *    $wgOut->wrapWikiMsg( "<div class='error'>\n$1\n</div>", 'some-error' );
3788          *
3789          * Is equivalent to:
3790          *
3791          *    $wgOut->addWikiText( "<div class='error'>\n"
3792          *        . wfMessage( 'some-error' )->plain() . "\n</div>" );
3793          *
3794          * The newline after the opening div is needed in some wikitext. See bug 19226.
3795          *
3796          * @param string $wrap
3797          */
3798         public function wrapWikiMsg( $wrap /*, ...*/ ) {
3799                 $msgSpecs = func_get_args();
3800                 array_shift( $msgSpecs );
3801                 $msgSpecs = array_values( $msgSpecs );
3802                 $s = $wrap;
3803                 foreach ( $msgSpecs as $n => $spec ) {
3804                         if ( is_array( $spec ) ) {
3805                                 $args = $spec;
3806                                 $name = array_shift( $args );
3807                                 if ( isset( $args['options'] ) ) {
3808                                         unset( $args['options'] );
3809                                         wfDeprecated(
3810                                                 'Adding "options" to ' . __METHOD__ . ' is no longer supported',
3811                                                 '1.20'
3812                                         );
3813                                 }
3814                         } else {
3815                                 $args = [];
3816                                 $name = $spec;
3817                         }
3818                         $s = str_replace( '$' . ( $n + 1 ), $this->msg( $name, $args )->plain(), $s );
3819                 }
3820                 $this->addWikiText( $s );
3821         }
3822
3823         /**
3824          * Enables/disables TOC, doesn't override __NOTOC__
3825          * @param bool $flag
3826          * @since 1.22
3827          */
3828         public function enableTOC( $flag = true ) {
3829                 $this->mEnableTOC = $flag;
3830         }
3831
3832         /**
3833          * @return bool
3834          * @since 1.22
3835          */
3836         public function isTOCEnabled() {
3837                 return $this->mEnableTOC;
3838         }
3839
3840         /**
3841          * Enables/disables section edit links, doesn't override __NOEDITSECTION__
3842          * @param bool $flag
3843          * @since 1.23
3844          */
3845         public function enableSectionEditLinks( $flag = true ) {
3846                 $this->mEnableSectionEditLinks = $flag;
3847         }
3848
3849         /**
3850          * @return bool
3851          * @since 1.23
3852          */
3853         public function sectionEditLinksEnabled() {
3854                 return $this->mEnableSectionEditLinks;
3855         }
3856
3857         /**
3858          * Helper function to setup the PHP implementation of OOUI to use in this request.
3859          *
3860          * @since 1.26
3861          * @param String $skinName The Skin name to determine the correct OOUI theme
3862          * @param String $dir Language direction
3863          */
3864         public static function setupOOUI( $skinName = '', $dir = 'ltr' ) {
3865                 $themes = ExtensionRegistry::getInstance()->getAttribute( 'SkinOOUIThemes' );
3866                 // Make keys (skin names) lowercase for case-insensitive matching.
3867                 $themes = array_change_key_case( $themes, CASE_LOWER );
3868                 $theme = isset( $themes[$skinName] ) ? $themes[$skinName] : 'MediaWiki';
3869                 // For example, 'OOUI\MediaWikiTheme'.
3870                 $themeClass = "OOUI\\{$theme}Theme";
3871                 OOUI\Theme::setSingleton( new $themeClass() );
3872                 OOUI\Element::setDefaultDir( $dir );
3873         }
3874
3875         /**
3876          * Add ResourceLoader module styles for OOUI and set up the PHP implementation of it for use with
3877          * MediaWiki and this OutputPage instance.
3878          *
3879          * @since 1.25
3880          */
3881         public function enableOOUI() {
3882                 self::setupOOUI(
3883                         strtolower( $this->getSkin()->getSkinName() ),
3884                         $this->getLanguage()->getDir()
3885                 );
3886                 $this->addModuleStyles( [
3887                         'oojs-ui-core.styles',
3888                         'oojs-ui.styles.icons',
3889                         'oojs-ui.styles.indicators',
3890                         'oojs-ui.styles.textures',
3891                         'mediawiki.widgets.styles',
3892                 ] );
3893         }
3894 }