OutputPage.php | searchcode

/includes/OutputPage.php

Large files files are truncated, but you can click here to view the full file

<?php
if ( !defined( 'MEDIAWIKI' ) ) {
	die( 1 );
}

/**
 * This class should be covered by a general architecture document which does
 * not exist as of January 2011.  This is one of the Core classes and should
 * be read at least once by any new developers.
 *
 * This class is used to prepare the final rendering. A skin is then
 * applied to the output parameters (links, javascript, html, categories ...).
 *
 * @todo FIXME: Another class handles sending the whole page to the client.
 *
 * Some comments comes from a pairing session between Zak Greant and Antoine Musso
 * in November 2010.
 *
 * @todo document
 */
class OutputPage extends ContextSource {
	/// Should be private. Used with addMeta() which adds <meta>
	var $mMetatags = array();

	/// <meta keyworkds="stuff"> most of the time the first 10 links to an article
	var $mKeywords = array();

	var $mLinktags = array();

	/// Additional stylesheets. Looks like this is for extensions. Might be replaced by resource loader.
	var $mExtStyles = array();

	/// Should be private - has getter and setter. Contains the HTML title
	var $mPagetitle = '';

	/// Contains all of the <body> content. Should be private we got set/get accessors and the append() method.
	var $mBodytext = '';

	/**
	 * Holds the debug lines that will be output as comments in page source if
	 * $wgDebugComments is enabled. See also $wgShowDebug.
	 * TODO: make a getter method for this
	 */
	public $mDebugtext = ''; // TODO: we might want to replace it by wfDebug() wfDebugLog()

	/// Should be private. Stores contents of <title> tag
	var $mHTMLtitle = '';

	/// Should be private. Is the displayed content related to the source of the corresponding wiki article.
	var $mIsarticle = false;

	/**
	 * Should be private. Has get/set methods properly documented.
	 * Stores "article flag" toggle.
	 */
	var $mIsArticleRelated = true;

	/**
	 * Should be private. We have to set isPrintable(). Some pages should
	 * never be printed (ex: redirections).
	 */
	var $mPrintable = false;

	/**
	 * Should be private. We have set/get/append methods.
	 *
	 * Contains the page subtitle. Special pages usually have some links here.
	 * Don't confuse with site subtitle added by skins.
	 */
	private $mSubtitle = array();

	var $mRedirect = '';
	var $mStatusCode;

	/**
	 * mLastModified and mEtag are used for sending cache control.
	 * The whole caching system should probably be moved into its own class.
	 */
	var $mLastModified = '';

	/**
	 * Should be private. No getter but used in sendCacheControl();
	 * Contains an HTTP Entity Tags (see RFC 2616 section 3.13) which is used
	 * as a unique identifier for the content. It is later used by the client
	 * to compare its cached version with the server version. Client sends
	 * headers If-Match and If-None-Match containing its locally cached ETAG value.
	 *
	 * To get more information, you will have to look at HTTP/1.1 protocol which
	 * is properly described in RFC 2616 : http://tools.ietf.org/html/rfc2616
	 */
	var $mETag = false;

	var $mCategoryLinks = array();
	var $mCategories = array();

	/// Should be private. Array of Interwiki Prefixed (non DB key) Titles (e.g. 'fr:Test page')
	var $mLanguageLinks = array();

	/**
	 * Should be private. Used for JavaScript (pre resource loader)
	 * We should split js / css.
	 * mScripts content is inserted as is in <head> by Skin. This might contains
	 * either a link to a stylesheet or inline css.
	 */
	var $mScripts = '';

	/**
	 * Inline CSS styles. Use addInlineStyle() sparsingly
	 */
	var $mInlineStyles = '';

	//
	var $mLinkColours;

	/**
	 * Used by skin template.
	 * Example: $tpl->set( 'displaytitle', $out->mPageLinkTitle );
	 */
	var $mPageLinkTitle = '';

	/// Array of elements in <head>. Parser might add its own headers!
	var $mHeadItems = array();

	// @todo FIXME: Next variables probably comes from the resource loader
	var $mModules = array(), $mModuleScripts = array(), $mModuleStyles = array(), $mModuleMessages = array();
	var $mResourceLoader;
	var $mJsConfigVars = array();

	/** @todo FIXME: Is this still used ?*/
	var $mInlineMsg = array();

	var $mTemplateIds = array();
	var $mImageTimeKeys = array();

	var $mRedirectCode = '';

	var $mFeedLinksAppendQuery = null;

	# What level of 'untrustworthiness' is allowed in CSS/JS modules loaded on this page?
	# @see ResourceLoaderModule::$origin
	# ResourceLoaderModule::ORIGIN_ALL is assumed unless overridden;
	protected $mAllowedModules = array(
		ResourceLoaderModule::TYPE_COMBINED => ResourceLoaderModule::ORIGIN_ALL,
	);

	/**
	 * @EasterEgg I just love the name for this self documenting variable.
	 * @todo document
	 */
	var $mDoNothing = false;

	// Parser related.
	var $mContainsOldMagic = 0, $mContainsNewMagic = 0;

	/**
	 * lazy initialised, use parserOptions()
	 * @var ParserOptions
	 */
	protected $mParserOptions = null;

	/**
	 * Handles the atom / rss links.
	 * We probably only support atom in 2011.
	 * Looks like a private variable.
	 * @see $wgAdvertisedFeedTypes
	 */
	var $mFeedLinks = array();

	// Gwicke work on squid caching? Roughly from 2003.
	var $mEnableClientCache = true;

	/**
	 * Flag if output should only contain the body of the article.
	 * Should be private.
	 */
	var $mArticleBodyOnly = false;

	var $mNewSectionLink = false;
	var $mHideNewSectionLink = false;

	/**
	 * Comes from the parser. This was probably made to load CSS/JS only
	 * if we had <gallery>. Used directly in CategoryPage.php
	 * Looks like resource loader can replace this.
	 */
	var $mNoGallery = false;

	// should be private.
	var $mPageTitleActionText = '';
	var $mParseWarnings = array();

	// Cache stuff. Looks like mEnableClientCache
	var $mSquidMaxage = 0;

	// @todo document
	var $mPreventClickjacking = true;

	/// should be private. To include the variable {{REVISIONID}}
	var $mRevisionId = null;
	private $mRevisionTimestamp = null;

	var $mFileVersion = null;

	/**
	 * An array of stylesheet filenames (relative from skins path), with options
	 * for CSS media, IE conditions, and RTL/LTR direction.
	 * For internal use; add settings in the skin via $this->addStyle()
	 *
	 * Style again! This seems like a code duplication since we already have
	 * mStyles. This is what makes OpenSource amazing.
	 */
	var $styles = array();

	/**
	 * Whether jQuery is already handled.
	 */
	protected $mJQueryDone = false;

	private $mIndexPolicy = 'index';
	private $mFollowPolicy = 'follow';
	private $mVaryHeader = array(
		'Accept-Encoding' => array( 'list-contains=gzip' ),
		'Cookie' => null
	);

	/**
	 * If the current page was reached through a redirect, $mRedirectedFrom contains the Title
	 * of the redirect.
	 *
	 * @var Title
	 */
	private $mRedirectedFrom = null;

	/**
	 * Constructor for OutputPage. This should not be called directly.
	 * Instead a new RequestContext should be created and it will implicitly create
	 * a OutputPage tied to that context.
	 */
	function __construct( IContextSource $context = null ) {
		if ( $context === null ) {
			# Extensions should use `new RequestContext` instead of `new OutputPage` now.
			wfDeprecated( __METHOD__ );
		} else {
			$this->setContext( $context );
		}
	}

	/**
	 * Redirect to $url rather than displaying the normal page
	 *
	 * @param $url String: URL
	 * @param $responsecode String: HTTP status code
	 */
	public function redirect( $url, $responsecode = '302' ) {
		# Strip newlines as a paranoia check for header injection in PHP<5.1.2
		$this->mRedirect = str_replace( "\n", '', $url );
		$this->mRedirectCode = $responsecode;
	}

	/**
	 * Get the URL to redirect to, or an empty string if not redirect URL set
	 *
	 * @return String
	 */
	public function getRedirect() {
		return $this->mRedirect;
	}

	/**
	 * Set the HTTP status code to send with the output.
	 *
	 * @param $statusCode Integer
	 */
	public function setStatusCode( $statusCode ) {
		$this->mStatusCode = $statusCode;
	}

	/**
	 * Add a new <meta> tag
	 * To add an http-equiv meta tag, precede the name with "http:"
	 *
	 * @param $name String tag name
	 * @param $val String tag value
	 */
	function addMeta( $name, $val ) {
		array_push( $this->mMetatags, array( $name, $val ) );
	}

	/**
	 * Add a keyword or a list of keywords in the page header
	 *
	 * @param $text String or array of strings
	 */
	function addKeyword( $text ) {
		if( is_array( $text ) ) {
			$this->mKeywords = array_merge( $this->mKeywords, $text );
		} else {
			array_push( $this->mKeywords, $text );
		}
	}

	/**
	 * Add a new \<link\> tag to the page header
	 *
	 * @param $linkarr Array: associative array of attributes.
	 */
	function addLink( $linkarr ) {
		array_push( $this->mLinktags, $linkarr );
	}

	/**
	 * Add a new \<link\> with "rel" attribute set to "meta"
	 *
	 * @param $linkarr Array: associative array mapping attribute names to their
	 *                 values, both keys and values will be escaped, and the
	 *                 "rel" attribute will be automatically added
	 */
	function addMetadataLink( $linkarr ) {
		$linkarr['rel'] = $this->getMetadataAttribute();
		$this->addLink( $linkarr );
	}

	/**
	 * Get the value of the "rel" attribute for metadata links
	 *
	 * @return String
	 */
	public function getMetadataAttribute() {
		# note: buggy CC software only reads first "meta" link
		static $haveMeta = false;
		if ( $haveMeta ) {
			return 'alternate meta';
		} else {
			$haveMeta = true;
			return 'meta';
		}
	}

	/**
	 * Add raw HTML to the list of scripts (including \<script\> tag, etc.)
	 *
	 * @param $script String: raw HTML
	 */
	function addScript( $script ) {
		$this->mScripts .= $script . "\n";
	}

	/**
	 * Register and add a stylesheet from an extension directory.
	 *
	 * @param $url String path to sheet.  Provide either a full url (beginning
	 *             with 'http', etc) or a relative path from the document root
	 *             (beginning with '/').  Otherwise it behaves identically to
	 *             addStyle() and draws from the /skins folder.
	 */
	public function addExtensionStyle( $url ) {
		array_push( $this->mExtStyles, $url );
	}

	/**
	 * Get all styles added by extensions
	 *
	 * @return Array
	 */
	function getExtStyle() {
		return $this->mExtStyles;
	}

	/**
	 * Add a JavaScript file out of skins/common, or a given relative path.
	 *
	 * @param $file String: filename in skins/common or complete on-server path
	 *              (/foo/bar.js)
	 * @param $version String: style version of the file. Defaults to $wgStyleVersion
	 */
	public function addScriptFile( $file, $version = null ) {
		global $wgStylePath, $wgStyleVersion;
		// See if $file parameter is an absolute URL or begins with a slash
		if( substr( $file, 0, 1 ) == '/' || preg_match( '#^[a-z]*://#i', $file ) ) {
			$path = $file;
		} else {
			$path = "{$wgStylePath}/common/{$file}";
		}
		if ( is_null( $version ) )
			$version = $wgStyleVersion;
		$this->addScript( Html::linkedScript( wfAppendQuery( $path, $version ) ) );
	}

	/**
	 * Add a self-contained script tag with the given contents
	 *
	 * @param $script String: JavaScript text, no <script> tags
	 */
	public function addInlineScript( $script ) {
		$this->mScripts .= Html::inlineScript( "\n$script\n" ) . "\n";
	}

	/**
	 * Get all registered JS and CSS tags for the header.
	 *
	 * @return String
	 */
	function getScript() {
		return $this->mScripts . $this->getHeadItems();
	}

	/**
	 * Filter an array of modules to remove insufficiently trustworthy members, and modules
	 * which are no longer registered (eg a page is cached before an extension is disabled)
	 * @param $modules Array
	 * @param $position String if not null, only return modules with this position
	 * @param $type string
	 * @return Array
	 */
	protected function filterModules( $modules, $position = null, $type = ResourceLoaderModule::TYPE_COMBINED ){
		$resourceLoader = $this->getResourceLoader();
		$filteredModules = array();
		foreach( $modules as $val ){
			$module = $resourceLoader->getModule( $val );
			if( $module instanceof ResourceLoaderModule
				&& $module->getOrigin() <= $this->getAllowedModules( $type )
				&& ( is_null( $position ) || $module->getPosition() == $position ) )
			{
				$filteredModules[] = $val;
			}
		}
		return $filteredModules;
	}

	/**
	 * Get the list of modules to include on this page
	 *
	 * @param $filter Bool whether to filter out insufficiently trustworthy modules
	 * @param $position String if not null, only return modules with this position
	 * @param $param string
	 * @return Array of module names
	 */
	public function getModules( $filter = false, $position = null, $param = 'mModules' ) {
		$modules = array_values( array_unique( $this->$param ) );
		return $filter
			? $this->filterModules( $modules, $position )
			: $modules;
	}

	/**
	 * Add one or more modules recognized by the resource loader. Modules added
	 * through this function will be loaded by the resource loader when the
	 * page loads.
	 *
	 * @param $modules Mixed: module name (string) or array of module names
	 */
	public function addModules( $modules ) {
		$this->mModules = array_merge( $this->mModules, (array)$modules );
	}

	/**
	 * Get the list of module JS to include on this page
	 *
	 * @param $filter
	 * @param $position
	 *
	 * @return array of module names
	 */
	public function getModuleScripts( $filter = false, $position = null ) {
		return $this->getModules( $filter, $position, 'mModuleScripts' );
	}

	/**
	 * Add only JS of one or more modules recognized by the resource loader. Module
	 * scripts added through this function will be loaded by the resource loader when
	 * the page loads.
	 *
	 * @param $modules Mixed: module name (string) or array of module names
	 */
	public function addModuleScripts( $modules ) {
		$this->mModuleScripts = array_merge( $this->mModuleScripts, (array)$modules );
	}

	/**
	 * Get the list of module CSS to include on this page
	 *
	 * @param $filter
	 * @param $position
	 *
	 * @return Array of module names
	 */
	public function getModuleStyles( $filter = false, $position = null ) {
		return $this->getModules( $filter,  $position, 'mModuleStyles' );
	}

	/**
	 * Add only CSS of one or more modules recognized by the resource loader. Module
	 * styles added through this function will be loaded by the resource loader when
	 * the page loads.
	 *
	 * @param $modules Mixed: module name (string) or array of module names
	 */
	public function addModuleStyles( $modules ) {
		$this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
	}

	/**
	 * Get the list of module messages to include on this page
	 *
	 * @param $filter
	 * @param $position
	 *
	 * @return Array of module names
	 */
	public function getModuleMessages( $filter = false, $position = null ) {
		return $this->getModules( $filter, $position, 'mModuleMessages' );
	}

	/**
	 * Add only messages of one or more modules recognized by the resource loader.
	 * Module messages added through this function will be loaded by the resource
	 * loader when the page loads.
	 *
	 * @param $modules Mixed: module name (string) or array of module names
	 */
	public function addModuleMessages( $modules ) {
		$this->mModuleMessages = array_merge( $this->mModuleMessages, (array)$modules );
	}

	/**
	 * Get an array of head items
	 *
	 * @return Array
	 */
	function getHeadItemsArray() {
		return $this->mHeadItems;
	}

	/**
	 * Get all header items in a string
	 *
	 * @return String
	 */
	function getHeadItems() {
		$s = '';
		foreach ( $this->mHeadItems as $item ) {
			$s .= $item;
		}
		return $s;
	}

	/**
	 * Add or replace an header item to the output
	 *
	 * @param $name String: item name
	 * @param $value String: raw HTML
	 */
	public function addHeadItem( $name, $value ) {
		$this->mHeadItems[$name] = $value;
	}

	/**
	 * Check if the header item $name is already set
	 *
	 * @param $name String: item name
	 * @return Boolean
	 */
	public function hasHeadItem( $name ) {
		return isset( $this->mHeadItems[$name] );
	}

	/**
	 * Set the value of the ETag HTTP header, only used if $wgUseETag is true
	 *
	 * @param $tag String: value of "ETag" header
	 */
	function setETag( $tag ) {
		$this->mETag = $tag;
	}

	/**
	 * Set whether the output should only contain the body of the article,
	 * without any skin, sidebar, etc.
	 * Used e.g. when calling with "action=render".
	 *
	 * @param $only Boolean: whether to output only the body of the article
	 */
	public function setArticleBodyOnly( $only ) {
		$this->mArticleBodyOnly = $only;
	}

	/**
	 * Return whether the output will contain only the body of the article
	 *
	 * @return Boolean
	 */
	public function getArticleBodyOnly() {
		return $this->mArticleBodyOnly;
	}

	/**
	 * checkLastModified tells the client to use the client-cached page if
	 * possible. If sucessful, the OutputPage is disabled so that
	 * any future call to OutputPage->output() have no effect.
	 *
	 * Side effect: sets mLastModified for Last-Modified header
	 *
	 * @param $timestamp string
	 *
	 * @return Boolean: true iff cache-ok headers was sent.
	 */
	public function checkLastModified( $timestamp ) {
		global $wgCachePages, $wgCacheEpoch;

		if ( !$timestamp || $timestamp == '19700101000000' ) {
			wfDebug( __METHOD__ . ": CACHE DISABLED, NO TIMESTAMP\n" );
			return false;
		}
		if( !$wgCachePages ) {
			wfDebug( __METHOD__ . ": CACHE DISABLED\n", false );
			return false;
		}
		if( $this->getUser()->getOption( 'nocache' ) ) {
			wfDebug( __METHOD__ . ": USER DISABLED CACHE\n", false );
			return false;
		}

		$timestamp = wfTimestamp( TS_MW, $timestamp );
		$modifiedTimes = array(
			'page' => $timestamp,
			'user' => $this->getUser()->getTouched(),
			'epoch' => $wgCacheEpoch
		);
		wfRunHooks( 'OutputPageCheckLastModified', array( &$modifiedTimes ) );

		$maxModified = max( $modifiedTimes );
		$this->mLastModified = wfTimestamp( TS_RFC2822, $maxModified );

		if( empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
			wfDebug( __METHOD__ . ": client did not send If-Modified-Since header\n", false );
			return false;
		}

		# Make debug info
		$info = '';
		foreach ( $modifiedTimes as $name => $value ) {
			if ( $info !== '' ) {
				$info .= ', ';
			}
			$info .= "$name=" . wfTimestamp( TS_ISO_8601, $value );
		}

		# IE sends sizes after the date like this:
		# Wed, 20 Aug 2003 06:51:19 GMT; length=5202
		# this breaks strtotime().
		$clientHeader = preg_replace( '/;.*$/', '', $_SERVER["HTTP_IF_MODIFIED_SINCE"] );

		wfSuppressWarnings(); // E_STRICT system time bitching
		$clientHeaderTime = strtotime( $clientHeader );
		wfRestoreWarnings();
		if ( !$clientHeaderTime ) {
			wfDebug( __METHOD__ . ": unable to parse the client's If-Modified-Since header: $clientHeader\n" );
			return false;
		}
		$clientHeaderTime = wfTimestamp( TS_MW, $clientHeaderTime );

		wfDebug( __METHOD__ . ": client sent If-Modified-Since: " .
			wfTimestamp( TS_ISO_8601, $clientHeaderTime ) . "\n", false );
		wfDebug( __METHOD__ . ": effective Last-Modified: " .
			wfTimestamp( TS_ISO_8601, $maxModified ) . "\n", false );
		if( $clientHeaderTime < $maxModified ) {
			wfDebug( __METHOD__ . ": STALE, $info\n", false );
			return false;
		}

		# Not modified
		# Give a 304 response code and disable body output
		wfDebug( __METHOD__ . ": NOT MODIFIED, $info\n", false );
		ini_set( 'zlib.output_compression', 0 );
		$this->getRequest()->response()->header( "HTTP/1.1 304 Not Modified" );
		$this->sendCacheControl();
		$this->disable();

		// Don't output a compressed blob when using ob_gzhandler;
		// it's technically against HTTP spec and seems to confuse
		// Firefox when the response gets split over two packets.
		wfClearOutputBuffers();

		return true;
	}

	/**
	 * Override the last modified timestamp
	 *
	 * @param $timestamp String: new timestamp, in a format readable by
	 *        wfTimestamp()
	 */
	public function setLastModified( $timestamp ) {
		$this->mLastModified = wfTimestamp( TS_RFC2822, $timestamp );
	}

	/**
	 * Set the robot policy for the page: <http://www.robotstxt.org/meta.html>
	 *
	 * @param $policy String: the literal string to output as the contents of
	 *   the meta tag.  Will be parsed according to the spec and output in
	 *   standardized form.
	 * @return null
	 */
	public function setRobotPolicy( $policy ) {
		$policy = Article::formatRobotPolicy( $policy );

		if( isset( $policy['index'] ) ) {
			$this->setIndexPolicy( $policy['index'] );
		}
		if( isset( $policy['follow'] ) ) {
			$this->setFollowPolicy( $policy['follow'] );
		}
	}

	/**
	 * Set the index policy for the page, but leave the follow policy un-
	 * touched.
	 *
	 * @param $policy string Either 'index' or 'noindex'.
	 * @return null
	 */
	public function setIndexPolicy( $policy ) {
		$policy = trim( $policy );
		if( in_array( $policy, array( 'index', 'noindex' ) ) ) {
			$this->mIndexPolicy = $policy;
		}
	}

	/**
	 * Set the follow policy for the page, but leave the index policy un-
	 * touched.
	 *
	 * @param $policy String: either 'follow' or 'nofollow'.
	 * @return null
	 */
	public function setFollowPolicy( $policy ) {
		$policy = trim( $policy );
		if( in_array( $policy, array( 'follow', 'nofollow' ) ) ) {
			$this->mFollowPolicy = $policy;
		}
	}

	/**
	 * Set the new value of the "action text", this will be added to the
	 * "HTML title", separated from it with " - ".
	 *
	 * @param $text String: new value of the "action text"
	 */
	public function setPageTitleActionText( $text ) {
		$this->mPageTitleActionText = $text;
	}

	/**
	 * Get the value of the "action text"
	 *
	 * @return String
	 */
	public function getPageTitleActionText() {
		if ( isset( $this->mPageTitleActionText ) ) {
			return $this->mPageTitleActionText;
		}
	}

	/**
	 * "HTML title" means the contents of <title>.
	 * It is stored as plain, unescaped text and will be run through htmlspecialchars in the skin file.
	 *
	 * @param $name string
	 */
	public function setHTMLTitle( $name ) {
		if ( $name instanceof Message ) {
			$this->mHTMLtitle = $name->setContext( $this->getContext() )->text();
		} else {
			$this->mHTMLtitle = $name;
		}
	}

	/**
	 * Return the "HTML title", i.e. the content of the <title> tag.
	 *
	 * @return String
	 */
	public function getHTMLTitle() {
		return $this->mHTMLtitle;
	}

	/**
	 * Set $mRedirectedFrom, the Title of the page which redirected us to the current page.
	 *
	 * param @t Title
	 */
	public function setRedirectedFrom( $t ) {
		$this->mRedirectedFrom = $t;
	}

	/**
	 * "Page title" means the contents of \<h1\>. It is stored as a valid HTML fragment.
	 * This function allows good tags like \<sup\> in the \<h1\> tag, but not bad tags like \<script\>.
	 * This function automatically sets \<title\> to the same content as \<h1\> but with all tags removed.
	 * Bad tags that were escaped in \<h1\> will still be escaped in \<title\>, and good tags like \<i\> will be dropped entirely.
	 *
	 * @param $name string|Message
	 */
	public function setPageTitle( $name ) {
		if ( $name instanceof Message ) {
			$name = $name->setContext( $this->getContext() )->text();
		}

		# change "<script>foo&bar</script>" to "&lt;script&gt;foo&amp;bar&lt;/script&gt;"
		# but leave "<i>foobar</i>" alone
		$nameWithTags = Sanitizer::normalizeCharReferences( Sanitizer::removeHTMLtags( $name ) );
		$this->mPagetitle = $nameWithTags;

		# change "<i>foo&amp;bar</i>" to "foo&bar"
		$this->setHTMLTitle( $this->msg( 'pagetitle' )->rawParams( Sanitizer::stripAllTags( $nameWithTags ) ) );
	}

	/**
	 * Return the "page title", i.e. the content of the \<h1\> tag.
	 *
	 * @return String
	 */
	public function getPageTitle() {
		return $this->mPagetitle;
	}

	/**
	 * Set the Title object to use
	 *
	 * @param $t Title object
	 */
	public function setTitle( Title $t ) {
		$this->getContext()->setTitle( $t );
	}


	/**
	 * Replace the subtile with $str
	 *
	 * @param $str String|Message: new value of the subtitle
	 */
	public function setSubtitle( $str ) {
		$this->clearSubtitle();
		$this->addSubtitle( $str );
	}

	/**
	 * Add $str to the subtitle
	 *
	 * @deprecated in 1.19; use addSubtitle() instead
	 * @param $str String|Message to add to the subtitle
	 */
	public function appendSubtitle( $str ) {
		$this->addSubtitle( $str );
	}

	/**
	 * Add $str to the subtitle
	 *
	 * @param $str String|Message to add to the subtitle
	 */
	public function addSubtitle( $str ) {
		if ( $str instanceof Message ) {
			$this->mSubtitle[] = $str->setContext( $this->getContext() )->parse();
		} else {
			$this->mSubtitle[] = $str;
		}
	}

	/**
	 * Add a subtitle containing a backlink to a page
	 *
	 * @param $title Title to link to
	 */
	public function addBacklinkSubtitle( Title $title ) {
		$query = array();
		if ( $title->isRedirect() ) {
			$query['redirect'] = 'no';
		}
		$this->addSubtitle( $this->msg( 'backlinksubtitle' )->rawParams( Linker::link( $title, null, array(), $query ) ) );
	}

	/**
	 * Clear the subtitles
	 */
	public function clearSubtitle() {
		$this->mSubtitle = array();
	}

	/**
	 * Get the subtitle
	 *
	 * @return String
	 */
	public function getSubtitle() {
		return implode( "<br />\n\t\t\t\t", $this->mSubtitle );
	}

	/**
	 * Set the page as printable, i.e. it'll be displayed with with all
	 * print styles included
	 */
	public function setPrintable() {
		$this->mPrintable = true;
	}

	/**
	 * Return whether the page is "printable"
	 *
	 * @return Boolean
	 */
	public function isPrintable() {
		return $this->mPrintable;
	}

	/**
	 * Disable output completely, i.e. calling output() will have no effect
	 */
	public function disable() {
		$this->mDoNothing = true;
	}

	/**
	 * Return whether the output will be completely disabled
	 *
	 * @return Boolean
	 */
	public function isDisabled() {
		return $this->mDoNothing;
	}

	/**
	 * Show an "add new section" link?
	 *
	 * @return Boolean
	 */
	public function showNewSectionLink() {
		return $this->mNewSectionLink;
	}

	/**
	 * Forcibly hide the new section link?
	 *
	 * @return Boolean
	 */
	public function forceHideNewSectionLink() {
		return $this->mHideNewSectionLink;
	}

	/**
	 * Add or remove feed links in the page header
	 * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
	 * for the new version
	 * @see addFeedLink()
	 *
	 * @param $show Boolean: true: add default feeds, false: remove all feeds
	 */
	public function setSyndicated( $show = true ) {
		if ( $show ) {
			$this->setFeedAppendQuery( false );
		} else {
			$this->mFeedLinks = array();
		}
	}

	/**
	 * Add default feeds to the page header
	 * This is mainly kept for backward compatibility, see OutputPage::addFeedLink()
	 * for the new version
	 * @see addFeedLink()
	 *
	 * @param $val String: query to append to feed links or false to output
	 *        default links
	 */
	public function setFeedAppendQuery( $val ) {
		global $wgAdvertisedFeedTypes;

		$this->mFeedLinks = array();

		foreach ( $wgAdvertisedFeedTypes as $type ) {
			$query = "feed=$type";
			if ( is_string( $val ) ) {
				$query .= '&' . $val;
			}
			$this->mFeedLinks[$type] = $this->getTitle()->getLocalURL( $query );
		}
	}

	/**
	 * Add a feed link to the page header
	 *
	 * @param $format String: feed type, should be a key of $wgFeedClasses
	 * @param $href String: URL
	 */
	public function addFeedLink( $format, $href ) {
		global $wgAdvertisedFeedTypes;

		if ( in_array( $format, $wgAdvertisedFeedTypes ) ) {
			$this->mFeedLinks[$format] = $href;
		}
	}

	/**
	 * Should we output feed links for this page?
	 * @return Boolean
	 */
	public function isSyndicated() {
		return count( $this->mFeedLinks ) > 0;
	}

	/**
	 * Return URLs for each supported syndication format for this page.
	 * @return array associating format keys with URLs
	 */
	public function getSyndicationLinks() {
		return $this->mFeedLinks;
	}

	/**
	 * Will currently always return null
	 *
	 * @return null
	 */
	public function getFeedAppendQuery() {
		return $this->mFeedLinksAppendQuery;
	}

	/**
	 * Set whether the displayed content is related to the source of the
	 * corresponding article on the wiki
	 * Setting true will cause the change "article related" toggle to true
	 *
	 * @param $v Boolean
	 */
	public function setArticleFlag( $v ) {
		$this->mIsarticle = $v;
		if ( $v ) {
			$this->mIsArticleRelated = $v;
		}
	}

	/**
	 * Return whether the content displayed page is related to the source of
	 * the corresponding article on the wiki
	 *
	 * @return Boolean
	 */
	public function isArticle() {
		return $this->mIsarticle;
	}

	/**
	 * Set whether this page is related an article on the wiki
	 * Setting false will cause the change of "article flag" toggle to false
	 *
	 * @param $v Boolean
	 */
	public function setArticleRelated( $v ) {
		$this->mIsArticleRelated = $v;
		if ( !$v ) {
			$this->mIsarticle = false;
		}
	}

	/**
	 * Return whether this page is related an article on the wiki
	 *
	 * @return Boolean
	 */
	public function isArticleRelated() {
		return $this->mIsArticleRelated;
	}

	/**
	 * Add new language links
	 *
	 * @param $newLinkArray Associative array mapping language code to the page
	 *                      name
	 */
	public function addLanguageLinks( $newLinkArray ) {
		$this->mLanguageLinks += $newLinkArray;
	}

	/**
	 * Reset the language links and add new language links
	 *
	 * @param $newLinkArray Associative array mapping language code to the page
	 *                      name
	 */
	public function setLanguageLinks( $newLinkArray ) {
		$this->mLanguageLinks = $newLinkArray;
	}

	/**
	 * Get the list of language links
	 *
	 * @return Array of Interwiki Prefixed (non DB key) Titles (e.g. 'fr:Test page')
	 */
	public function getLanguageLinks() {
		return $this->mLanguageLinks;
	}

	/**
	 * Add an array of categories, with names in the keys
	 *
	 * @param $categories Array mapping category name => sort key
	 */
	public function addCategoryLinks( $categories ) {
		global $wgContLang;

		if ( !is_array( $categories ) || count( $categories ) == 0 ) {
			return;
		}

		# Add the links to a LinkBatch
		$arr = array( NS_CATEGORY => $categories );
		$lb = new LinkBatch;
		$lb->setArray( $arr );

		# Fetch existence plus the hiddencat property
		$dbr = wfGetDB( DB_SLAVE );
		$res = $dbr->select( array( 'page', 'page_props' ),
			array( 'page_id', 'page_namespace', 'page_title', 'page_len', 'page_is_redirect', 'page_latest', 'pp_value' ),
			$lb->constructSet( 'page', $dbr ),
			__METHOD__,
			array(),
			array( 'page_props' => array( 'LEFT JOIN', array( 'pp_propname' => 'hiddencat', 'pp_page = page_id' ) ) )
		);

		# Add the results to the link cache
		$lb->addResultToCache( LinkCache::singleton(), $res );

		# Set all the values to 'normal'. This can be done with array_fill_keys in PHP 5.2.0+
		$categories = array_combine(
			array_keys( $categories ),
			array_fill( 0, count( $categories ), 'normal' )
		);

		# Mark hidden categories
		foreach ( $res as $row ) {
			if ( isset( $row->pp_value ) ) {
				$categories[$row->page_title] = 'hidden';
			}
		}

		# Add the remaining categories to the skin
		if ( wfRunHooks( 'OutputPageMakeCategoryLinks', array( &$this, $categories, &$this->mCategoryLinks ) ) ) {
			foreach ( $categories as $category => $type ) {
				$origcategory = $category;
				$title = Title::makeTitleSafe( NS_CATEGORY, $category );
				$wgContLang->findVariantLink( $category, $title, true );
				if ( $category != $origcategory ) {
					if ( array_key_exists( $category, $categories ) ) {
						continue;
					}
				}
				$text = $wgContLang->convertHtml( $title->getText() );
				$this->mCategories[] = $title->getText();
				$this->mCategoryLinks[$type][] = Linker::link( $title, $text );
			}
		}
	}

	/**
	 * Reset the category links (but not the category list) and add $categories
	 *
	 * @param $categories Array mapping category name => sort key
	 */
	public function setCategoryLinks( $categories ) {
		$this->mCategoryLinks = array();
		$this->addCategoryLinks( $categories );
	}

	/**
	 * Get the list of category links, in a 2-D array with the following format:
	 * $arr[$type][] = $link, where $type is either "normal" or "hidden" (for
	 * hidden categories) and $link a HTML fragment with a link to the category
	 * page
	 *
	 * @return Array
	 */
	public function getCategoryLinks() {
		return $this->mCategoryLinks;
	}

	/**
	 * Get the list of category names this page belongs to
	 *
	 * @return Array of strings
	 */
	public function getCategories() {
		return $this->mCategories;
	}

	/**
	 * Do not allow scripts which can be modified by wiki users to load on this page;
	 * only allow scripts bundled with, or generated by, the software.
	 */
	public function disallowUserJs() {
		$this->reduceAllowedModules(
			ResourceLoaderModule::TYPE_SCRIPTS,
			ResourceLoaderModule::ORIGIN_CORE_INDIVIDUAL
		);
	}

	/**
	 * Return whether user JavaScript is allowed for this page
	 * @deprecated since 1.18 Load modules with ResourceLoader, and origin and
	 *     trustworthiness is identified and enforced automagically.
	 *     Will be removed in 1.20.
	 * @return Boolean
	 */
	public function isUserJsAllowed() {
		wfDeprecated( __METHOD__, '1.18' );
		return $this->getAllowedModules( ResourceLoaderModule::TYPE_SCRIPTS ) >= ResourceLoaderModule::ORIGIN_USER_INDIVIDUAL;
	}

	/**
	 * Show what level of JavaScript / CSS untrustworthiness is allowed on this page
	 * @see ResourceLoaderModule::$origin
	 * @param $type String ResourceLoaderModule TYPE_ constant
	 * @return Int ResourceLoaderModule ORIGIN_ class constant
	 */
	public function getAllowedModules( $type ){
		if( $type == ResourceLoaderModule::TYPE_COMBINED ){
			return min( array_values( $this->mAllowedModules ) );
		} else {
			return isset( $this->mAllowedModules[$type] )
				? $this->mAllowedModules[$type]
				: ResourceLoaderModule::ORIGIN_ALL;
		}
	}

	/**
	 * Set the highest level of CSS/JS untrustworthiness allowed
	 * @param  $type String ResourceLoaderModule TYPE_ constant
	 * @param  $level Int ResourceLoaderModule class constant
	 */
	public function setAllowedModules( $type, $level ){
		$this->mAllowedModules[$type] = $level;
	}

	/**
	 * As for setAllowedModules(), but don't inadvertantly make the page more accessible
	 * @param  $type String
	 * @param  $level Int ResourceLoaderModule class constant
	 */
	public function reduceAllowedModules( $type, $level ){
		$this->mAllowedModules[$type] = min( $this->getAllowedModules($type), $level );
	}

	/**
	 * Prepend $text to the body HTML
	 *
	 * @param $text String: HTML
	 */
	public function prependHTML( $text ) {
		$this->mBodytext = $text . $this->mBodytext;
	}

	/**
	 * Append $text to the body HTML
	 *
	 * @param $text String: HTML
	 */
	public function addHTML( $text ) {
		$this->mBodytext .= $text;
	}

	/**
	 * Shortcut for adding an Html::element via addHTML.
	 *
	 * @since 1.19
	 *
	 * @param $element string
	 * @param $attribs array
	 * @param $contents string
	 */
	public function addElement( $element, $attribs = array(), $contents = '' ) {
		$this->addHTML( Html::element( $element, $attribs, $contents ) );
	}

	/**
	 * Clear the body HTML
	 */
	public function clearHTML() {
		$this->mBodytext = '';
	}

	/**
	 * Get the body HTML
	 *
	 * @return String: HTML
	 */
	public function getHTML() {
		return $this->mBodytext;
	}

	/**
	 * Add $text to the debug output
	 *
	 * @param $text String: debug text
	 */
	public function debug( $text ) {
		$this->mDebugtext .= $text;
	}

	/**
	 * Get/set the ParserOptions object to use for wikitext parsing
	 *
	 * @param $options either the ParserOption to use or null to only get the
	 *                 current ParserOption object
	 * @return ParserOptions object
	 */
	public function parserOptions( $options = null ) {
		if ( !$this->mParserOptions ) {
			$this->mParserOptions = ParserOptions::newFromContext( $this->getContext() );
			$this->mParserOptions->setEditSection( false );
		}
		return wfSetVar( $this->mParserOptions, $options );
	}

	/**
	 * Set the revision ID which will be seen by the wiki text parser
	 * for things such as embedded {{REVISIONID}} variable use.
	 *
	 * @param $revid Mixed: an positive integer, or null
	 * @return Mixed: previous value
	 */
	public function setRevisionId( $revid ) {
		$val = is_null( $revid ) ? null : intval( $revid );
		return wfSetVar( $this->mRevisionId, $val );
	}

	/**
	 * Get the displayed revision ID
	 *
	 * @return Integer
	 */
	public function getRevisionId() {
		return $this->mRevisionId;
	}

	/**
	 * Set the timestamp of the revision which will be displayed. This is used
	 * to avoid a extra DB call in Skin::lastModified().
	 *
	 * @param $revid Mixed: string, or null
	 * @return Mixed: previous value
	 */
	public function setRevisionTimestamp( $timestmap ) {
		return wfSetVar( $this->mRevisionTimestamp, $timestmap );
	}

	/**
	 * Get the timestamp of displayed revision.
	 * This will be null if not filled by setRevisionTimestamp().
	 *
	 * @return String or null
	 */
	public function getRevisionTimestamp() {
		return $this->mRevisionTimestamp;
	}

	/**
	 * Set the displayed file version
	 *
	 * @param $file File|false
	 * @return Mixed: previous value
	 */
	public function setFileVersion( $file ) {
		$val = null;
		if ( $file instanceof File && $file->exists() ) {
			$val = array( 'time' => $file->getTimestamp(), 'sha1' => $file->getSha1() );
		}
		return wfSetVar( $this->mFileVersion, $val, true );
	}

	/**
	 * Get the displayed file version
	 *
	 * @return Array|null ('time' => MW timestamp, 'sha1' => sha1)
	 */
	public function getFileVersion() {
		return $this->mFileVersion;
	}

	/**
	 * Get the templates used on this page
	 *
	 * @return Array (namespace => dbKey => revId)
	 * @since 1.18
	 */
	public function getTemplateIds() {
		return $this->mTemplateIds;
	}

	/**
	 * Get the files used on this page
	 *
	 * @return Array (dbKey => array('time' => MW timestamp or null, 'sha1' => sha1 or ''))
	 * @since 1.18
	 */
	public function getFileSearchOptions() {
		return $this->mImageTimeKeys;
	}

	/**
	 * Convert wikitext to HTML and add it to the buffer
	 * Default assumes that the current page title will be used.
	 *
	 * @param $text String
	 * @param $linestart Boolean: is this the start of a line?
	 * @param $interface Boolean: is this text in the user interface language?
	 */
	public function addWikiText( $text, $linestart = true, $interface = true ) {
		$title = $this->getTitle(); // Work arround E_STRICT
		$this->addWikiTextTitle( $text, $title, $linestart, /*tidy*/false, $interface );
	}

	/**
	 * Add wikitext with a custom Title object
	 *
	 * @param $text String: wikitext
	 * @param $title Title object
	 * @param $linestart Boolean: is this the start of a line?
	 */
	public function addWikiTextWithTitle( $text, &$title, $linestart = true ) {
		$this->addWikiTextTitle( $text, $title, $linestart );
	}

	/**
	 * Add wikitext with a custom Title object and tidy enabled.
	 *
	 * @param $text String: wikitext
	 * @param $title Title object
	 * @param $linestart Boolean: is this the start of a line?
	 */
	function addWikiTextTitleTidy( $text, &$title, $linestart = true ) {
		$this->addWikiTextTitle( $text, $title, $linestart, true );
	}

	/**
	 * Add wikitext with tidy enabled
	 *
	 * @param $text String: wikitext
	 * @param $linestart Boolean: is this the start of a line?
	 */
	public function addWikiTextTidy( $text, $linestart = true ) {
		$title = $this->getTitle();
		$this->addWikiTextTitleTidy( $text, $title, $linestart );
	}

	/**
	 * Add wikitext with a custom Title object
	 *
	 * @param $text String: wikitext
	 * @param $title Title object
	 * @param $linestart Boolean: is this the start of a line?
	 * @param $tidy Boolean: whether to use tidy
	 * @param $interface Boolean: whether it is an interface message
	 *								(for example disables conversion)
	 */
	public function addWikiTextTitle( $text, &$title, $linestart, $tidy = false, $interface = false ) {
		global $wgParser;

		wfProfileIn( __METHOD__ );

		$popts = $this->parserOptions();
		$oldTidy = $popts->setTidy( $tidy );
		$popts->setInterfaceMessage( (bool) $interface );

		$parserOutput = $wgParser->parse(
			$text, $title, $popts,
			$linestart, true, $this->mRevisionId
		);

		$popts->setTidy( $oldTidy );

		$this->addParserOutput( $parserOutput );

		wfProfileOut( __METHOD__ );
	}

	/**
	 * Add a ParserOutput object, but without Html
	 *
	 * @param $parserOutput ParserOutput object
	 */
	public function addParserOutputNoText( &$parserOutput ) {
		$this->mLanguageLinks += $parserOutput->getLanguageLinks();
		$this->addCategoryLinks( $parserOutput->getCategories() );
		$this->mNewSectionLink = $parserOutput->getNewSection();
		$this->mHideNewSectionLink = $parserOutput->getHideNewSection();

		$this->mParseWarnings = $parserOutput->getWarnings();
		if ( !$parserOutput->isCacheable() ) {
			$this->enableClientCache( false );
		}
		$this->mNoGallery = $parserOutput->getNoGallery();
		$this->mHeadItems = array_merge( $this->mHeadItems, $parserOutput->getHeadItems() );
		$this->addModules( $parserOutput->getModules() );
		$this->addModuleScripts( $parserOutput->getModuleScripts() );
		$this->addModuleStyles( $parserOutput->getModuleStyles() );
		$this->addModuleMessages( $parserOutput->getModuleMessages() );

		// Template versioning...
		foreach ( (array)$parserOutput->getTemplateIds() as $ns => $dbks ) {
			if ( isset( $this->mTemplateIds[$ns] ) ) {
				$this->mTemplateIds[$ns] = $dbks + $this->mTemplateIds[$ns];
			} else {
				$this->mTemplateIds[$ns] = $dbks;
			}
		}
		// File versioning...
		foreach ( (array)$parserOutput->getFileSearchOptions() as $dbk => $data ) {
			$this->mImageTimeKeys[$dbk] = $data;
		}

		// Hooks registered in the object
		global $wgParserOutputHooks;
		foreach ( $parserOutput->getOutputHooks() as $hookInfo ) {
			list( $hookName, $data ) = $hookInfo;
			if ( isset( $wgParserOutputHooks[$hookName] ) ) {
				call_user_func( $wgParserOutputHooks[$hookName], $this, $parserOutput, $data );
			}
		}

		wfRunHooks( 'OutputPageParserOutput', array( &$this, $parserOutput ) );
	}

	/**
	 * Add a ParserOutput object
	 *
	 * @param $parserOutput ParserOutput
	 */
	function addParserOutput( &$parserOutput ) {
		$this->addParserOutputNoText( $parserOutput );
		$text = $parserOutput->getText();
		wfRunHooks( 'OutputPageBeforeHTML', array( &$this, &$text ) );
		$this->addHTML( $text );
	}


	/**
	 * Add the output of a QuickTemplate to the output buffer
	 *
	 * @param $template QuickTemplate
	 */
	public function addTemplate( &$template ) {
		ob_start();
		$template->execute();
		$this->addHTML( ob_get_contents() );
		ob_end_clean();
	}

	/**
	 * Parse wikitext and return the HTML.
	 *
	 * @param $text String
	 * @param $linestart Boolean: is this the start of a line?
	 * @param $interface Boolean: use interface language ($wgLang instead of
	 *                   $wgContLang) while parsing language sensitive magic
	 *                   words like GRAMMAR and PLURAL. This also disables
	 *					 LanguageConverter.
	 * @param $language  Language object: target language object, will override
	 *                   $interface
	 * @return String: HTML
	 */
	public function parse( $text, $linestart = true, $interface = false, $language = null ) {
		global $wgParser;

		if( is_null( $this->getTitle() ) ) {
			throw new MWException( 'Empty $mTitle in ' . __METHOD__ );
		}

		$popts = $this->parserOptions();
		if ( $interface ) {
			$popts->setInterfaceMessage( true );
		}
		if ( $language !== null ) {
			$oldLang = $popts->setTargetLanguage( $language );
		}

		$parserOutput = $wgParser->parse(
			$text, $this->getTitle(), $popts,
			$linestart, true, $this->mRevisionId
		);

		if ( $interface ) {
			$popts->setInterfaceMessage( false );
		}
		if ( $language !== null ) {
			$popts->setTargetLanguage( $oldLang );
		}

		return $parserOutput->getText();
	}

	/**
	 * Parse wikitext, strip paragraphs, and return the HTML.
	 *
	 * @param $text String
	 * @param $linestart Boolean: is this the start of a line?
	 * @param $interface Boolean: use interface language ($wgLang instead of
	 *                   $wgContLang) while parsing language sensitive magic
	 *                   words like GRAMMAR and PLURAL
	 * @return String: HTML
	 */
	public function parseInline( $text, $linestart = true, $interface = false ) {
		$parsed = $this->parse( $text, $linestart, $interface );

		$m = array();
		if ( preg_match( '/^<p>(.*)\n?<\/p>\n?/sU', $parsed, $m ) ) {
			$parsed = $m[1];
		}

		return $parsed;
	}

	/**
	 * Set the value of the "s-maxage" part of the "Cache-control" HTTP header
	 *
	 * @param $maxage Integer: maximum cache time on the Squid, in seconds.
	 */
	public function setSquidMaxage( $maxage ) {
		$this->mSquidMaxage = $maxage;
	}

	/**
	 * Use enableClientCache(false) to force it to send nocache headers
	 *
	 * @param $state bool
	 *
	 * @return bool
	 */
	public function enableClientCache( $state ) {
		return wfSetVar( $this->mEnableClientCache, $state );
	}

	/**
	 * Get the list of cookies that will influence on the cache
	 *
	 * @return Array
	 */
	function getCacheVaryCookies() {
		global $wgCookiePrefix, $wgCacheVaryCookies;
		static $cookies;
		if ( $cookies === null ) {
			$cookies = array_merge(
				array(
					"{$wgCookiePrefix}Token",
					"{$wgCookiePrefix}LoggedOut",
					session_name()
				),
				$wgCacheVaryCookies
			);
			wfRunHooks( 'GetCacheVaryCookies', array( $this, &$cookies ) );
		}
		return $cookies;
	}

	/**
	 * Return whether this page is not cacheable because "useskin" or "uselang"
	 * URL parameters were passed.
	 *
	 * @return Boolean
	 */
	function uncacheableBecauseRequestVars() {
		$request = $this->getRequest();
		return $request->getText( 'useskin', false ) === false
			&& $request->getText( 'uselang', false ) === false;
	}

	/**
	 * Check if the request has a cache-varying cookie header
	 * If it does, it's very important that we don't allow public caching
	 *
	 * @return Boolean
	 */
	function haveCacheVaryCookies() {
		$cookieHeader = $this->getRequest()->getHeader( 'cookie' );
		if ( $cookieHeader === false ) {
			return false;
		}
		$cvCookies = $this->getCacheVaryCookies();
		foreach ( $cvCookies as $cookieName ) {
			# Check for a simple string match, like the way squid does it
			if ( strpos( $cookieHeader, $cookieName ) !== false ) {
				wfDebug( __METHOD__ . ": found $cookieName\n" );
				return true;
			}
		}
		wfDebug( __METHOD__ . ": no cache-varying cookies found\n" );
		return false;
	}

	/**
	 * Add an HTTP header that will influence on the cache
	 *
	 * @param $header String: header name
	 * @param $option Array|null
	 * @todo FIXME: Document the $option parameter; it appears to be for
	 *        X-Vary-Options but what format is acceptable?
	 */
	public function addVaryHeader( $header, $option = null ) {
		if ( !array_key_exists( $header, $this->mVaryHeader ) ) {
			$this->mVaryHeader[$header] = (array)$option;
		} elseif( is_array( $option ) ) {
			if( is_array( $this->mVaryHeader[$header] ) ) {
				$this->mVaryHeader[$header] = array_merge( $this->mVaryHeader[$header], $option );
			} else {
				$this->mVaryHeader[$header] = $option;
			}
		}
		$this->mVaryHeader[$header] = array_unique( (array)$this->mVaryHeader[$header] );
	}

	/**
	 * Get a complete X-Vary-Options header
	 *
	 * @return String
	 */
	public function getXVO() {
		$cvCookies = $this->getCacheVaryCookies();

		$cookiesOption = array();
		foreach ( $cvCookies as $cookieName ) {
			$cookiesOption[] = 'string-contains=' . $cookieName;
		}
		$this->addVaryHeader( 'Cookie', $cookiesOption );

		$headers = array();
		foreach( $this->mVaryHeader as $header => $option ) {
			$newheader = $header;
			if( is_array( $option ) ) {
				$newheader .= ';' . implode( ';', $option );
			}
			$headers[] = $newheader;
		}
		$xvo = 'X-Vary-Options: ' . implode( ',', $headers );

		return $xvo;
	}

	/**
	 * bug 21672: Add Accept-Language to Vary and XVO headers
	 * if there's no 'variant' parameter existed in GET.
	 *
	 * For example:
	 *   /w/index.php?title=Main_page should always be served; but
	 *   /w/index.php?title=Main_page&variant=zh-cn should never be served.
	 */
	function addAcceptLanguage() {
		$lang = $this->getTitle()->getPageLanguage();
		if( !$this->getRequest()->getCheck( 'variant' ) && $lang->hasVariants() ) {
			$variants = $lang->getVariants();
			$aloption = array();
			foreach ( $variants as $variant ) {
				if( $variant === $lang->getCode() ) {
					continue;
				} else {
					$aloption[] = 'string-contains=' . $variant;

					// IE and some other browsers use another form of language code
					// in their Accept-Language header, like "zh-CN" or "zh-TW".
					// We should handle these too.
					$ievariant = explode( '-', $variant );
					if ( count( $ievariant ) == 2 ) {
						$ievariant[1] = strtoupper( $ievariant[1] );
						$ievariant = implode( '-', $ievariant );
						$aloption[] = 'string-contains=' . $ievariant;
					}
				}
			}
			$this->addVaryHeader( 'Accept-Language', $aloption );
		}
	}

	/**
	 * Set a flag which will cause an X-Frame-Options header appropriate for
	 * edit pages to be sent. The header value is controlled by
	 * $wgEditPageFrameOptions.
	 *
	 * This is the default for special pages. If you display a CSRF-protected
	 * form on an ordinary view page, then you need to call this function.
	 *
	 * @param $enable bool
	 */
	public function preventClickjacking( $enable = true ) {
		$this->mPreventClickjacking = $enable;
	}

	/**
	 * Turn off frame-breaking. Alias for $this->preventClickjacking(false).
	 * This can be called from pages which do not contain any CSRF-protected
	 * HTML form.
	 */
	public function allowClickjacking() {
		$this->mPreventClickjacking = false;
	}

	/**
	 * Get the X-Frame-Options header value (without the name part), or false
	 * if there isn't one. This is used by Skin to determine whether to enable
	 * JavaScript frame-breaking, for clients that don't support X-Frame-Options.
	 *
	 * @return string
	 */
	public function getFrameOptions() {
		global $wgBreakFrames, $wgEditPageFrameOptions;
		if…
Large files files are truncated, but you can click here to view the full file