includes/parser/ParserOutput.php

   1 <?php
   2
   3 /**
   4  * Output of the PHP parser.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  19  * http://www.gnu.org/copyleft/gpl.html
  20  *
  21  * @file
  22  * @ingroup Parser
  23  */
  24 class ParserOutput extends CacheTime {
  25         public $mText,                       # The output text
  26                 $mLanguageLinks,              # List of the full text of language links, in the order they appear
  27                 $mCategories,                 # Map of category names to sort keys
  28                 $mTitleText,                  # title text of the chosen language variant
  29                 $mLinks = array(),            # 2-D map of NS/DBK to ID for the links in the document. ID=zero for broken.
  30                 $mTemplates = array(),        # 2-D map of NS/DBK to ID for the template references. ID=zero for broken.
  31                 $mTemplateIds = array(),      # 2-D map of NS/DBK to rev ID for the template references. ID=zero for broken.
  32                 $mImages = array(),           # DB keys of the images used, in the array key only
  33                 $mFileSearchOptions = array(), # DB keys of the images used mapped to sha1 and MW timestamp
  34                 $mExternalLinks = array(),    # External link URLs, in the key only
  35                 $mInterwikiLinks = array(),   # 2-D map of prefix/DBK (in keys only) for the inline interwiki links in the document.
  36                 $mNewSection = false,         # Show a new section link?
  37                 $mHideNewSection = false,     # Hide the new section link?
  38                 $mNoGallery = false,          # No gallery on category page? (__NOGALLERY__)
  39                 $mHeadItems = array(),        # Items to put in the <head> section
  40                 $mModules = array(),          # Modules to be loaded by the resource loader
  41                 $mModuleScripts = array(),    # Modules of which only the JS will be loaded by the resource loader
  42                 $mModuleStyles = array(),     # Modules of which only the CSSS will be loaded by the resource loader
  43                 $mModuleMessages = array(),   # Modules of which only the messages will be loaded by the resource loader
  44                 $mJsConfigVars = array(),     # JavaScript config variable for mw.config combined with this page
  45                 $mOutputHooks = array(),      # Hook tags as per $wgParserOutputHooks
  46                 $mWarnings = array(),         # Warning text to be returned to the user. Wikitext formatted, in the key only
  47                 $mSections = array(),         # Table of contents
  48                 $mEditSectionTokens = false,  # prefix/suffix markers if edit sections were output as tokens
  49                 $mProperties = array(),       # Name/value pairs to be cached in the DB
  50                 $mTOCHTML = '',               # HTML of the TOC
  51                 $mTimestamp,                  # Timestamp of the revision
  52                 $mTOCEnabled = true;          # Whether TOC should be shown, can't override __NOTOC__
  53                 private $mIndexPolicy = '';       # 'index' or 'noindex'?  Any other value will result in no change.
  54                 private $mAccessedOptions = array(); # List of ParserOptions (stored in the keys)
  55                 private $mSecondaryDataUpdates = array(); # List of DataUpdate, used to save info from the page somewhere else.
  56                 private $mExtensionData = array(); # extra data used by extensions
  57                 private $mLimitReportData = array(); # Parser limit report data
  58                 private $mParseStartTime = array(); # Timestamps for getTimeSinceStart()
  59                 private $mPreventClickjacking = false; # Whether to emit X-Frame-Options: DENY
  60
  61         const EDITSECTION_REGEX =
  62                 '#<(?:mw:)?editsection page="(.*?)" section="(.*?)"(?:/>|>(.*?)(</(?:mw:)?editsection>))#';
  63
  64         public function __construct( $text = '', $languageLinks = array(), $categoryLinks = array(),
  65                 $containsOldMagic = false, $titletext = ''
  66         ) {
  67                 $this->mText = $text;
  68                 $this->mLanguageLinks = $languageLinks;
  69                 $this->mCategories = $categoryLinks;
  70                 $this->mContainsOldMagic = $containsOldMagic;
  71                 $this->mTitleText = $titletext;
  72         }
  73
  74         public function getText() {
  75                 wfProfileIn( __METHOD__ );
  76                 $text = $this->mText;
  77                 if ( $this->mEditSectionTokens ) {
  78                         $text = preg_replace_callback(
  79                                 ParserOutput::EDITSECTION_REGEX,
  80                                 function ( $m ) {
  81                                         global $wgOut, $wgLang;
  82                                         $editsectionPage = Title::newFromText( htmlspecialchars_decode( $m[1] ) );
  83                                         $editsectionSection = htmlspecialchars_decode( $m[2] );
  84                                         $editsectionContent = isset( $m[4] ) ? $m[3] : null;
  85
  86                                         if ( !is_object( $editsectionPage ) ) {
  87                                                 throw new MWException( "Bad parser output text." );
  88                                         }
  89
  90                                         $skin = $wgOut->getSkin();
  91                                         return call_user_func_array(
  92                                                 array( $skin, 'doEditSectionLink' ),
  93                                                 array( $editsectionPage, $editsectionSection,
  94                                                         $editsectionContent, $wgLang->getCode() )
  95                                         );
  96                                 },
  97                                 $text
  98                         );
  99                 } else {
 100                         $text = preg_replace( ParserOutput::EDITSECTION_REGEX, '', $text );
 101                 }
 102
 103                 // If you have an old cached version of this class - sorry, you can't disable the TOC
 104                 if ( isset( $this->mTOCEnabled ) && $this->mTOCEnabled ) {
 105                         $text = str_replace( array( Parser::TOC_START, Parser::TOC_END ), '', $text );
 106                 } else {
 107                         $text = preg_replace(
 108                                 '#' . preg_quote( Parser::TOC_START ) . '.*?' . preg_quote( Parser::TOC_END ) . '#s',
 109                                 '',
 110                                 $text
 111                         );
 112                 }
 113                 wfProfileOut( __METHOD__ );
 114                 return $text;
 115         }
 116
 117         public function &getLanguageLinks() {
 118                 return $this->mLanguageLinks;
 119         }
 120
 121         public function getInterwikiLinks() {
 122                 return $this->mInterwikiLinks;
 123         }
 124
 125         public function getCategoryLinks() {
 126                 return array_keys( $this->mCategories );
 127         }
 128
 129         public function &getCategories() {
 130                 return $this->mCategories;
 131         }
 132
 133         public function getTitleText() {
 134                 return $this->mTitleText;
 135         }
 136
 137         public function getSections() {
 138                 return $this->mSections;
 139         }
 140
 141         public function getEditSectionTokens() {
 142                 return $this->mEditSectionTokens;
 143         }
 144
 145         public function &getLinks() {
 146                 return $this->mLinks;
 147         }
 148
 149         public function &getTemplates() {
 150                 return $this->mTemplates;
 151         }
 152
 153         public function &getTemplateIds() {
 154                 return $this->mTemplateIds;
 155         }
 156
 157         public function &getImages() {
 158                 return $this->mImages;
 159         }
 160
 161         public function &getFileSearchOptions() {
 162                 return $this->mFileSearchOptions;
 163         }
 164
 165         public function &getExternalLinks() {
 166                 return $this->mExternalLinks;
 167         }
 168
 169         public function getNoGallery() {
 170                 return $this->mNoGallery;
 171         }
 172
 173         public function getHeadItems() {
 174                 return $this->mHeadItems;
 175         }
 176
 177         public function getModules() {
 178                 return $this->mModules;
 179         }
 180
 181         public function getModuleScripts() {
 182                 return $this->mModuleScripts;
 183         }
 184
 185         public function getModuleStyles() {
 186                 return $this->mModuleStyles;
 187         }
 188
 189         public function getModuleMessages() {
 190                 return $this->mModuleMessages;
 191         }
 192
 193         /** @since 1.23 */
 194         public function getJsConfigVars() {
 195                 return $this->mJsConfigVars;
 196         }
 197
 198         public function getOutputHooks() {
 199                 return (array)$this->mOutputHooks;
 200         }
 201
 202         public function getWarnings() {
 203                 return array_keys( $this->mWarnings );
 204         }
 205
 206         public function getIndexPolicy() {
 207                 return $this->mIndexPolicy;
 208         }
 209
 210         public function getTOCHTML() {
 211                 return $this->mTOCHTML;
 212         }
 213
 214         public function getTimestamp() {
 215                 return $this->mTimestamp;
 216         }
 217
 218         public function getLimitReportData() {
 219                 return $this->mLimitReportData;
 220         }
 221
 222         public function getTOCEnabled() {
 223                 return $this->mTOCEnabled;
 224         }
 225
 226         public function setText( $text ) {
 227                 return wfSetVar( $this->mText, $text );
 228         }
 229
 230         public function setLanguageLinks( $ll ) {
 231                 return wfSetVar( $this->mLanguageLinks, $ll );
 232         }
 233
 234         public function setCategoryLinks( $cl ) {
 235                 return wfSetVar( $this->mCategories, $cl );
 236         }
 237
 238         public function setTitleText( $t ) {
 239                 return wfSetVar( $this->mTitleText, $t );
 240         }
 241
 242         public function setSections( $toc ) {
 243                 return wfSetVar( $this->mSections, $toc );
 244         }
 245
 246         public function setEditSectionTokens( $t ) {
 247                 return wfSetVar( $this->mEditSectionTokens, $t );
 248         }
 249
 250         public function setIndexPolicy( $policy ) {
 251                 return wfSetVar( $this->mIndexPolicy, $policy );
 252         }
 253
 254         public function setTOCHTML( $tochtml ) {
 255                 return wfSetVar( $this->mTOCHTML, $tochtml );
 256         }
 257
 258         public function setTimestamp( $timestamp ) {
 259                 return wfSetVar( $this->mTimestamp, $timestamp );
 260         }
 261
 262         public function setTOCEnabled( $flag ) {
 263                 return wfSetVar( $this->mTOCEnabled, $flag );
 264         }
 265
 266         public function addCategory( $c, $sort ) {
 267                 $this->mCategories[$c] = $sort;
 268         }
 269
 270         public function addLanguageLink( $t ) {
 271                 $this->mLanguageLinks[] = $t;
 272         }
 273
 274         public function addWarning( $s ) {
 275                 $this->mWarnings[$s] = 1;
 276         }
 277
 278         public function addOutputHook( $hook, $data = false ) {
 279                 $this->mOutputHooks[] = array( $hook, $data );
 280         }
 281
 282         public function setNewSection( $value ) {
 283                 $this->mNewSection = (bool)$value;
 284         }
 285         public function hideNewSection( $value ) {
 286                 $this->mHideNewSection = (bool)$value;
 287         }
 288         public function getHideNewSection() {
 289                 return (bool)$this->mHideNewSection;
 290         }
 291         public function getNewSection() {
 292                 return (bool)$this->mNewSection;
 293         }
 294
 295         /**
 296          * Checks, if a url is pointing to the own server
 297          *
 298          * @param string $internal The server to check against
 299          * @param string $url The url to check
 300          * @return bool
 301          */
 302         public static function isLinkInternal( $internal, $url ) {
 303                 return (bool)preg_match( '/^' .
 304                         # If server is proto relative, check also for http/https links
 305                         ( substr( $internal, 0, 2 ) === '//' ? '(?:https?:)?' : '' ) .
 306                         preg_quote( $internal, '/' ) .
 307                         # check for query/path/anchor or end of link in each case
 308                         '(?:[\?\/\#]|$)/i',
 309                         $url
 310                 );
 311         }
 312
 313         public function addExternalLink( $url ) {
 314                 # We don't register links pointing to our own server, unless... :-)
 315                 global $wgServer, $wgRegisterInternalExternals;
 316
 317                 $registerExternalLink = true;
 318                 if ( !$wgRegisterInternalExternals ) {
 319                         $registerExternalLink = !self::isLinkInternal( $wgServer, $url );
 320                 }
 321                 if ( $registerExternalLink ) {
 322                         $this->mExternalLinks[$url] = 1;
 323                 }
 324         }
 325
 326         /**
 327          * Record a local or interwiki inline link for saving in future link tables.
 328          *
 329          * @param Title $title
 330          * @param int|null $id Optional known page_id so we can skip the lookup
 331          */
 332         public function addLink( Title $title, $id = null ) {
 333                 if ( $title->isExternal() ) {
 334                         // Don't record interwikis in pagelinks
 335                         $this->addInterwikiLink( $title );
 336                         return;
 337                 }
 338                 $ns = $title->getNamespace();
 339                 $dbk = $title->getDBkey();
 340                 if ( $ns == NS_MEDIA ) {
 341                         // Normalize this pseudo-alias if it makes it down here...
 342                         $ns = NS_FILE;
 343                 } elseif ( $ns == NS_SPECIAL ) {
 344                         // We don't record Special: links currently
 345                         // It might actually be wise to, but we'd need to do some normalization.
 346                         return;
 347                 } elseif ( $dbk === '' ) {
 348                         // Don't record self links -  [[#Foo]]
 349                         return;
 350                 }
 351                 if ( !isset( $this->mLinks[$ns] ) ) {
 352                         $this->mLinks[$ns] = array();
 353                 }
 354                 if ( is_null( $id ) ) {
 355                         $id = $title->getArticleID();
 356                 }
 357                 $this->mLinks[$ns][$dbk] = $id;
 358         }
 359
 360         /**
 361          * Register a file dependency for this output
 362          * @param string $name Title dbKey
 363          * @param string $timestamp MW timestamp of file creation (or false if non-existing)
 364          * @param string $sha1 Base 36 SHA-1 of file (or false if non-existing)
 365          * @return void
 366          */
 367         public function addImage( $name, $timestamp = null, $sha1 = null ) {
 368                 $this->mImages[$name] = 1;
 369                 if ( $timestamp !== null && $sha1 !== null ) {
 370                         $this->mFileSearchOptions[$name] = array( 'time' => $timestamp, 'sha1' => $sha1 );
 371                 }
 372         }
 373
 374         /**
 375          * Register a template dependency for this output
 376          * @param Title $title
 377          * @param int $page_id
 378          * @param int $rev_id
 379          * @return void
 380          */
 381         public function addTemplate( $title, $page_id, $rev_id ) {
 382                 $ns = $title->getNamespace();
 383                 $dbk = $title->getDBkey();
 384                 if ( !isset( $this->mTemplates[$ns] ) ) {
 385                         $this->mTemplates[$ns] = array();
 386                 }
 387                 $this->mTemplates[$ns][$dbk] = $page_id;
 388                 if ( !isset( $this->mTemplateIds[$ns] ) ) {
 389                         $this->mTemplateIds[$ns] = array();
 390                 }
 391                 $this->mTemplateIds[$ns][$dbk] = $rev_id; // For versioning
 392         }
 393
 394         /**
 395          * @param Title $title Title object, must be an interwiki link
 396          * @throws MWException If given invalid input
 397          */
 398         public function addInterwikiLink( $title ) {
 399                 if ( !$title->isExternal() ) {
 400                         throw new MWException( 'Non-interwiki link passed, internal parser error.' );
 401                 }
 402                 $prefix = $title->getInterwiki();
 403                 if ( !isset( $this->mInterwikiLinks[$prefix] ) ) {
 404                         $this->mInterwikiLinks[$prefix] = array();
 405                 }
 406                 $this->mInterwikiLinks[$prefix][$title->getDBkey()] = 1;
 407         }
 408
 409         /**
 410          * Add some text to the "<head>".
 411          * If $tag is set, the section with that tag will only be included once
 412          * in a given page.
 413          * @param string $section
 414          * @param string|bool $tag
 415          */
 416         public function addHeadItem( $section, $tag = false ) {
 417                 if ( $tag !== false ) {
 418                         $this->mHeadItems[$tag] = $section;
 419                 } else {
 420                         $this->mHeadItems[] = $section;
 421                 }
 422         }
 423
 424         public function addModules( $modules ) {
 425                 $this->mModules = array_merge( $this->mModules, (array)$modules );
 426         }
 427
 428         public function addModuleScripts( $modules ) {
 429                 $this->mModuleScripts = array_merge( $this->mModuleScripts, (array)$modules );
 430         }
 431
 432         public function addModuleStyles( $modules ) {
 433                 $this->mModuleStyles = array_merge( $this->mModuleStyles, (array)$modules );
 434         }
 435
 436         public function addModuleMessages( $modules ) {
 437                 $this->mModuleMessages = array_merge( $this->mModuleMessages, (array)$modules );
 438         }
 439
 440         /**
 441          * Add one or more variables to be set in mw.config in JavaScript.
 442          *
 443          * @param string|array $keys Key or array of key/value pairs.
 444          * @param mixed $value [optional] Value of the configuration variable.
 445          * @since 1.23
 446          */
 447         public function addJsConfigVars( $keys, $value = null ) {
 448                 if ( is_array( $keys ) ) {
 449                         foreach ( $keys as $key => $value ) {
 450                                 $this->mJsConfigVars[$key] = $value;
 451                         }
 452                         return;
 453                 }
 454
 455                 $this->mJsConfigVars[$keys] = $value;
 456         }
 457
 458         /**
 459          * Copy items from the OutputPage object into this one
 460          *
 461          * @param OutputPage $out
 462          */
 463         public function addOutputPageMetadata( OutputPage $out ) {
 464                 $this->addModules( $out->getModules() );
 465                 $this->addModuleScripts( $out->getModuleScripts() );
 466                 $this->addModuleStyles( $out->getModuleStyles() );
 467                 $this->addModuleMessages( $out->getModuleMessages() );
 468                 $this->addJsConfigVars( $out->getJsConfigVars() );
 469
 470                 $this->mHeadItems = array_merge( $this->mHeadItems, $out->getHeadItemsArray() );
 471                 $this->mPreventClickjacking = $this->mPreventClickjacking || $out->getPreventClickjacking();
 472         }
 473
 474         /**
 475          * Override the title to be used for display
 476          * -- this is assumed to have been validated
 477          * (check equal normalisation, etc.)
 478          *
 479          * @param string $text Desired title text
 480          */
 481         public function setDisplayTitle( $text ) {
 482                 $this->setTitleText( $text );
 483                 $this->setProperty( 'displaytitle', $text );
 484         }
 485
 486         /**
 487          * Get the title to be used for display
 488          *
 489          * @return string
 490          */
 491         public function getDisplayTitle() {
 492                 $t = $this->getTitleText();
 493                 if ( $t === '' ) {
 494                         return false;
 495                 }
 496                 return $t;
 497         }
 498
 499         /**
 500          * Fairly generic flag setter thingy.
 501          * @param string $flag
 502          */
 503         public function setFlag( $flag ) {
 504                 $this->mFlags[$flag] = true;
 505         }
 506
 507         public function getFlag( $flag ) {
 508                 return isset( $this->mFlags[$flag] );
 509         }
 510
 511         /**
 512          * Set a property to be stored in the page_props database table.
 513          *
 514          * page_props is a key value store indexed by the page ID. This allows
 515          * the parser to set a property on a page which can then be quickly
 516          * retrieved given the page ID or via a DB join when given the page
 517          * title.
 518          *
 519          * Since 1.23, page_props are also indexed by numeric value, to allow
 520          * for efficient "top k" queries of pages wrt a given property.
 521          *
 522          * setProperty() is thus used to propagate properties from the parsed
 523          * page to request contexts other than a page view of the currently parsed
 524          * article.
 525          *
 526          * Some applications examples:
 527          *
 528          *   * To implement hidden categories, hiding pages from category listings
 529          *     by storing a property.
 530          *
 531          *   * Overriding the displayed article title.
 532          *   @see ParserOutput::setDisplayTitle()
 533          *
 534          *   * To implement image tagging, for example displaying an icon on an
 535          *     image thumbnail to indicate that it is listed for deletion on
 536          *     Wikimedia Commons.
 537          *     This is not actually implemented, yet but would be pretty cool.
 538          *
 539          * @note Do not use setProperty() to set a property which is only used
 540          * in a context where the ParserOutput object itself is already available,
 541          * for example a normal page view. There is no need to save such a property
 542          * in the database since the text is already parsed. You can just hook
 543          * OutputPageParserOutput and get your data out of the ParserOutput object.
 544          *
 545          * If you are writing an extension where you want to set a property in the
 546          * parser which is used by an OutputPageParserOutput hook, you have to
 547          * associate the extension data directly with the ParserOutput object.
 548          * Since MediaWiki 1.21, you can use setExtensionData() to do this:
 549          *
 550          * @par Example:
 551          * @code
 552          *    $parser->getOutput()->setExtensionData( 'my_ext_foo', '...' );
 553          * @endcode
 554          *
 555          * And then later, in OutputPageParserOutput or similar:
 556          *
 557          * @par Example:
 558          * @code
 559          *    $output->getExtensionData( 'my_ext_foo' );
 560          * @endcode
 561          *
 562          * In MediaWiki 1.20 and older, you have to use a custom member variable
 563          * within the ParserOutput object:
 564          *
 565          * @par Example:
 566          * @code
 567          *    $parser->getOutput()->my_ext_foo = '...';
 568          * @endcode
 569          *
 570          */
 571         public function setProperty( $name, $value ) {
 572                 $this->mProperties[$name] = $value;
 573         }
 574
 575         /**
 576          * @param string $name The property name to look up.
 577          *
 578          * @return mixed|bool The value previously set using setProperty(). False if null or no value
 579          * was set for the given property name.
 580          *
 581          * @note You need to use getProperties() to check for boolean and null properties.
 582          */
 583         public function getProperty( $name ) {
 584                 return isset( $this->mProperties[$name] ) ? $this->mProperties[$name] : false;
 585         }
 586
 587         public function unsetProperty( $name ) {
 588                 unset( $this->mProperties[$name] );
 589         }
 590
 591         public function getProperties() {
 592                 if ( !isset( $this->mProperties ) ) {
 593                         $this->mProperties = array();
 594                 }
 595                 return $this->mProperties;
 596         }
 597
 598         /**
 599          * Returns the options from its ParserOptions which have been taken
 600          * into account to produce this output or false if not available.
 601          * @return array
 602          */
 603         public function getUsedOptions() {
 604                 if ( !isset( $this->mAccessedOptions ) ) {
 605                         return array();
 606                 }
 607                 return array_keys( $this->mAccessedOptions );
 608         }
 609
 610         /**
 611          * Tags a parser option for use in the cache key for this parser output.
 612          * Registered as a watcher at ParserOptions::registerWatcher() by Parser::clearState().
 613          *
 614          * @see ParserCache::getKey
 615          * @see ParserCache::save
 616          * @see ParserOptions::addExtraKey
 617          * @see ParserOptions::optionsHash
 618          * @param string $option
 619          */
 620         public function recordOption( $option ) {
 621                 $this->mAccessedOptions[$option] = true;
 622         }
 623
 624         /**
 625          * Adds an update job to the output. Any update jobs added to the output will
 626          * eventually be executed in order to store any secondary information extracted
 627          * from the page's content. This is triggered by calling getSecondaryDataUpdates()
 628          * and is used for forward links updates on edit and backlink updates by jobs.
 629          *
 630          * @since 1.20
 631          *
 632          * @param DataUpdate $update
 633          */
 634         public function addSecondaryDataUpdate( DataUpdate $update ) {
 635                 $this->mSecondaryDataUpdates[] = $update;
 636         }
 637
 638         /**
 639          * Returns any DataUpdate jobs to be executed in order to store secondary information
 640          * extracted from the page's content, including a LinksUpdate object for all links stored in
 641          * this ParserOutput object.
 642          *
 643          * @note Avoid using this method directly, use ContentHandler::getSecondaryDataUpdates()
 644          *   instead! The content handler may provide additional update objects.
 645          *
 646          * @since 1.20
 647          *
 648          * @param Title $title The title of the page we're updating. If not given, a title object will
 649          *    be created based on $this->getTitleText()
 650          * @param bool $recursive Queue jobs for recursive updates?
 651          *
 652          * @return array An array of instances of DataUpdate
 653          */
 654         public function getSecondaryDataUpdates( Title $title = null, $recursive = true ) {
 655                 if ( is_null( $title ) ) {
 656                         $title = Title::newFromText( $this->getTitleText() );
 657                 }
 658
 659                 $linksUpdate = new LinksUpdate( $title, $this, $recursive );
 660
 661                 return array_merge( $this->mSecondaryDataUpdates, array( $linksUpdate ) );
 662         }
 663
 664         /**
 665          * Attaches arbitrary data to this ParserObject. This can be used to store some information in
 666          * the ParserOutput object for later use during page output. The data will be cached along with
 667          * the ParserOutput object, but unlike data set using setProperty(), it is not recorded in the
 668          * database.
 669          *
 670          * This method is provided to overcome the unsafe practice of attaching extra information to a
 671          * ParserObject by directly assigning member variables.
 672          *
 673          * To use setExtensionData() to pass extension information from a hook inside the parser to a
 674          * hook in the page output, use this in the parser hook:
 675          *
 676          * @par Example:
 677          * @code
 678          *    $parser->getOutput()->setExtensionData( 'my_ext_foo', '...' );
 679          * @endcode
 680          *
 681          * And then later, in OutputPageParserOutput or similar:
 682          *
 683          * @par Example:
 684          * @code
 685          *    $output->getExtensionData( 'my_ext_foo' );
 686          * @endcode
 687          *
 688          * In MediaWiki 1.20 and older, you have to use a custom member variable
 689          * within the ParserOutput object:
 690          *
 691          * @par Example:
 692          * @code
 693          *    $parser->getOutput()->my_ext_foo = '...';
 694          * @endcode
 695          *
 696          * @since 1.21
 697          *
 698          * @param string $key The key for accessing the data. Extensions should take care to avoid
 699          *   conflicts in naming keys. It is suggested to use the extension's name as a prefix.
 700          *
 701          * @param mixed $value The value to set. Setting a value to null is equivalent to removing
 702          *   the value.
 703          */
 704         public function setExtensionData( $key, $value ) {
 705                 if ( $value === null ) {
 706                         unset( $this->mExtensionData[$key] );
 707                 } else {
 708                         $this->mExtensionData[$key] = $value;
 709                 }
 710         }
 711
 712         /**
 713          * Gets extensions data previously attached to this ParserOutput using setExtensionData().
 714          * Typically, such data would be set while parsing the page, e.g. by a parser function.
 715          *
 716          * @since 1.21
 717          *
 718          * @param string $key The key to look up.
 719          *
 720          * @return mixed|null The value previously set for the given key using setExtensionData()
 721          *         or null if no value was set for this key.
 722          */
 723         public function getExtensionData( $key ) {
 724                 if ( isset( $this->mExtensionData[$key] ) ) {
 725                         return $this->mExtensionData[$key];
 726                 }
 727
 728                 return null;
 729         }
 730
 731         private static function getTimes( $clock = null ) {
 732                 $ret = array();
 733                 if ( !$clock || $clock === 'wall' ) {
 734                         $ret['wall'] = microtime( true );
 735                 }
 736                 if ( ( !$clock || $clock === 'cpu' ) && function_exists( 'getrusage' ) ) {
 737                         $ru = getrusage();
 738                         $ret['cpu'] = $ru['ru_utime.tv_sec'] + $ru['ru_utime.tv_usec'] / 1e6;
 739                         $ret['cpu'] += $ru['ru_stime.tv_sec'] + $ru['ru_stime.tv_usec'] / 1e6;
 740                 }
 741                 return $ret;
 742         }
 743
 744         /**
 745          * Resets the parse start timestamps for future calls to getTimeSinceStart()
 746          * @since 1.22
 747          */
 748         public function resetParseStartTime() {
 749                 $this->mParseStartTime = self::getTimes();
 750         }
 751
 752         /**
 753          * Returns the time since resetParseStartTime() was last called
 754          *
 755          * Clocks available are:
 756          *  - wall: Wall clock time
 757          *  - cpu: CPU time (requires getrusage)
 758          *
 759          * @since 1.22
 760          * @param string $clock
 761          * @return float|null
 762          */
 763         public function getTimeSinceStart( $clock ) {
 764                 if ( !isset( $this->mParseStartTime[$clock] ) ) {
 765                         return null;
 766                 }
 767
 768                 $end = self::getTimes( $clock );
 769                 return $end[$clock] - $this->mParseStartTime[$clock];
 770         }
 771
 772         /**
 773          * Sets parser limit report data for a key
 774          *
 775          * The key is used as the prefix for various messages used for formatting:
 776          *  - $key: The label for the field in the limit report
 777          *  - $key-value-text: Message used to format the value in the "NewPP limit
 778          *      report" HTML comment. If missing, uses $key-format.
 779          *  - $key-value-html: Message used to format the value in the preview
 780          *      limit report table. If missing, uses $key-format.
 781          *  - $key-value: Message used to format the value. If missing, uses "$1".
 782          *
 783          * Note that all values are interpreted as wikitext, and so should be
 784          * encoded with htmlspecialchars() as necessary, but should avoid complex
 785          * HTML for sanity of display in the "NewPP limit report" comment.
 786          *
 787          * @since 1.22
 788          * @param string $key Message key
 789          * @param mixed $value Appropriate for Message::params()
 790          */
 791         public function setLimitReportData( $key, $value ) {
 792                 $this->mLimitReportData[$key] = $value;
 793         }
 794
 795         /**
 796          * Get or set the prevent-clickjacking flag
 797          *
 798          * @since 1.24
 799          * @param bool|null $flag New flag value, or null to leave it unchanged
 800          * @return bool Old flag value
 801          */
 802         public function preventClickjacking( $flag = null ) {
 803                 return wfSetVar( $this->mPreventClickjacking, $flag );
 804         }
 805
 806         /**
 807          * Save space for for serialization by removing useless values
 808          * @return array
 809          */
 810         public function __sleep() {
 811                 return array_diff(
 812                         array_keys( get_object_vars( $this ) ),
 813                         array( 'mSecondaryDataUpdates', 'mParseStartTime' )
 814                 );
 815         }
 816 }