includes/resourceloader/ResourceLoaderWikiModule.php

   1 <?php
   2 /**
   3  * Abstraction for ResourceLoader modules that pull from wiki pages.
   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  * @author Trevor Parscal
  22  * @author Roan Kattouw
  23  */
  24
  25 use MediaWiki\Linker\LinkTarget;
  26 use MediaWiki\Storage\RevisionRecord;
  27 use Wikimedia\Assert\Assert;
  28 use Wikimedia\Rdbms\Database;
  29 use Wikimedia\Rdbms\IDatabase;
  30 use MediaWiki\MediaWikiServices;
  31
  32 /**
  33  * Abstraction for ResourceLoader modules which pull from wiki pages
  34  *
  35  * This can only be used for wiki pages in the MediaWiki and User namespaces,
  36  * because of its dependence on the functionality of Title::isUserConfigPage()
  37  * and Title::isSiteConfigPage().
  38  *
  39  * This module supports being used as a placeholder for a module on a remote wiki.
  40  * To do so, getDB() must be overloaded to return a foreign database object that
  41  * allows local wikis to query page metadata.
  42  *
  43  * Safe for calls on local wikis are:
  44  * - Option getters:
  45  *   - getGroup()
  46  *   - getPages()
  47  * - Basic methods that strictly involve the foreign database
  48  *   - getDB()
  49  *   - isKnownEmpty()
  50  *   - getTitleInfo()
  51  */
  52 class ResourceLoaderWikiModule extends ResourceLoaderModule {
  53
  54         // Origin defaults to users with sitewide authority
  55         protected $origin = self::ORIGIN_USER_SITEWIDE;
  56
  57         // In-process cache for title info, structured as an array
  58         // [
  59         //  <batchKey> // Pipe-separated list of sorted keys from getPages
  60         //   => [
  61         //     <titleKey> => [ // Normalised title key
  62         //       'page_len' => ..,
  63         //       'page_latest' => ..,
  64         //       'page_touched' => ..,
  65         //     ]
  66         //   ]
  67         // ]
  68         // @see self::fetchTitleInfo()
  69         // @see self::makeTitleKey()
  70         protected $titleInfo = [];
  71
  72         // List of page names that contain CSS
  73         protected $styles = [];
  74
  75         // List of page names that contain JavaScript
  76         protected $scripts = [];
  77
  78         // Group of module
  79         protected $group;
  80
  81         /**
  82          * @param array|null $options For back-compat, this can be omitted in favour of overwriting
  83          *  getPages.
  84          */
  85         public function __construct( array $options = null ) {
  86                 if ( $options === null ) {
  87                         return;
  88                 }
  89
  90                 foreach ( $options as $member => $option ) {
  91                         switch ( $member ) {
  92                                 case 'styles':
  93                                 case 'scripts':
  94                                 case 'group':
  95                                 case 'targets':
  96                                         $this->{$member} = $option;
  97                                         break;
  98                         }
  99                 }
 100         }
 101
 102         /**
 103          * Subclasses should return an associative array of resources in the module.
 104          * Keys should be the title of a page in the MediaWiki or User namespace.
 105          *
 106          * Values should be a nested array of options.  The supported keys are 'type' and
 107          * (CSS only) 'media'.
 108          *
 109          * For scripts, 'type' should be 'script'.
 110          *
 111          * For stylesheets, 'type' should be 'style'.
 112          * There is an optional media key, the value of which can be the
 113          * medium ('screen', 'print', etc.) of the stylesheet.
 114          *
 115          * @param ResourceLoaderContext $context
 116          * @return array
 117          */
 118         protected function getPages( ResourceLoaderContext $context ) {
 119                 $config = $this->getConfig();
 120                 $pages = [];
 121
 122                 // Filter out pages from origins not allowed by the current wiki configuration.
 123                 if ( $config->get( 'UseSiteJs' ) ) {
 124                         foreach ( $this->scripts as $script ) {
 125                                 $pages[$script] = [ 'type' => 'script' ];
 126                         }
 127                 }
 128
 129                 if ( $config->get( 'UseSiteCss' ) ) {
 130                         foreach ( $this->styles as $style ) {
 131                                 $pages[$style] = [ 'type' => 'style' ];
 132                         }
 133                 }
 134
 135                 return $pages;
 136         }
 137
 138         /**
 139          * Get group name
 140          *
 141          * @return string
 142          */
 143         public function getGroup() {
 144                 return $this->group;
 145         }
 146
 147         /**
 148          * Get the Database handle used for computing the module version.
 149          *
 150          * Subclasses may override this to return a foreign database, which would
 151          * allow them to register a module on wiki A that fetches wiki pages from
 152          * wiki B.
 153          *
 154          * The way this works is that the local module is a placeholder that can
 155          * only computer a module version hash. The 'source' of the module must
 156          * be set to the foreign wiki directly. Methods getScript() and getContent()
 157          * will not use this handle and are not valid on the local wiki.
 158          *
 159          * @return IDatabase
 160          */
 161         protected function getDB() {
 162                 return wfGetDB( DB_REPLICA );
 163         }
 164
 165         /**
 166          * @param string $titleText
 167          * @param ResourceLoaderContext|null $context (but passing null is deprecated)
 168          * @return null|string
 169          * @since 1.32 added the $context parameter
 170          */
 171         protected function getContent( $titleText, ResourceLoaderContext $context = null ) {
 172                 $title = Title::newFromText( $titleText );
 173                 if ( !$title ) {
 174                         return null; // Bad title
 175                 }
 176
 177                 $content = $this->getContentObj( $title, $context );
 178                 if ( !$content ) {
 179                         return null; // No content found
 180                 }
 181
 182                 $handler = $content->getContentHandler();
 183                 if ( $handler->isSupportedFormat( CONTENT_FORMAT_CSS ) ) {
 184                         $format = CONTENT_FORMAT_CSS;
 185                 } elseif ( $handler->isSupportedFormat( CONTENT_FORMAT_JAVASCRIPT ) ) {
 186                         $format = CONTENT_FORMAT_JAVASCRIPT;
 187                 } else {
 188                         return null; // Bad content model
 189                 }
 190
 191                 return $content->serialize( $format );
 192         }
 193
 194         /**
 195          * @param Title $title
 196          * @param ResourceLoaderContext|null $context (but passing null is deprecated)
 197          * @param int|null $maxRedirects Maximum number of redirects to follow. If
 198          *  null, uses $wgMaxRedirects
 199          * @return Content|null
 200          * @since 1.32 added the $context and $maxRedirects parameters
 201          */
 202         protected function getContentObj(
 203                 Title $title, ResourceLoaderContext $context = null, $maxRedirects = null
 204         ) {
 205                 if ( $context === null ) {
 206                         wfDeprecated( __METHOD__ . ' without a ResourceLoader context', '1.32' );
 207                 }
 208
 209                 $overrideCallback = $context ? $context->getContentOverrideCallback() : null;
 210                 $content = $overrideCallback ? call_user_func( $overrideCallback, $title ) : null;
 211                 if ( $content ) {
 212                         if ( !$content instanceof Content ) {
 213                                 $this->getLogger()->error(
 214                                         'Bad content override for "{title}" in ' . __METHOD__,
 215                                         [ 'title' => $title->getPrefixedText() ]
 216                                 );
 217                                 return null;
 218                         }
 219                 } else {
 220                         $revision = Revision::newKnownCurrent( wfGetDB( DB_REPLICA ), $title );
 221                         if ( !$revision ) {
 222                                 return null;
 223                         }
 224                         $content = $revision->getContent( RevisionRecord::RAW );
 225
 226                         if ( !$content ) {
 227                                 $this->getLogger()->error(
 228                                         'Failed to load content of JS/CSS page "{title}" in ' . __METHOD__,
 229                                         [ 'title' => $title->getPrefixedText() ]
 230                                 );
 231                                 return null;
 232                         }
 233                 }
 234
 235                 if ( $content && $content->isRedirect() ) {
 236                         if ( $maxRedirects === null ) {
 237                                 $maxRedirects = $this->getConfig()->get( 'MaxRedirects' ) ?: 0;
 238                         }
 239                         if ( $maxRedirects > 0 ) {
 240                                 $newTitle = $content->getRedirectTarget();
 241                                 return $newTitle ? $this->getContentObj( $newTitle, $context, $maxRedirects - 1 ) : null;
 242                         }
 243                 }
 244
 245                 return $content;
 246         }
 247
 248         /**
 249          * @param ResourceLoaderContext $context
 250          * @return bool
 251          */
 252         public function shouldEmbedModule( ResourceLoaderContext $context ) {
 253                 $overrideCallback = $context->getContentOverrideCallback();
 254                 if ( $overrideCallback && $this->getSource() === 'local' ) {
 255                         foreach ( $this->getPages( $context ) as $page => $info ) {
 256                                 $title = Title::newFromText( $page );
 257                                 if ( $title && call_user_func( $overrideCallback, $title ) !== null ) {
 258                                         return true;
 259                                 }
 260                         }
 261                 }
 262
 263                 return parent::shouldEmbedModule( $context );
 264         }
 265
 266         /**
 267          * @param ResourceLoaderContext $context
 268          * @return string JavaScript code
 269          */
 270         public function getScript( ResourceLoaderContext $context ) {
 271                 $scripts = '';
 272                 foreach ( $this->getPages( $context ) as $titleText => $options ) {
 273                         if ( $options['type'] !== 'script' ) {
 274                                 continue;
 275                         }
 276                         $script = $this->getContent( $titleText, $context );
 277                         if ( strval( $script ) !== '' ) {
 278                                 $script = $this->validateScriptFile( $titleText, $script );
 279                                 $scripts .= ResourceLoader::makeComment( $titleText ) . $script . "\n";
 280                         }
 281                 }
 282                 return $scripts;
 283         }
 284
 285         /**
 286          * @param ResourceLoaderContext $context
 287          * @return array
 288          */
 289         public function getStyles( ResourceLoaderContext $context ) {
 290                 $styles = [];
 291                 foreach ( $this->getPages( $context ) as $titleText => $options ) {
 292                         if ( $options['type'] !== 'style' ) {
 293                                 continue;
 294                         }
 295                         $media = $options['media'] ?? 'all';
 296                         $style = $this->getContent( $titleText, $context );
 297                         if ( strval( $style ) === '' ) {
 298                                 continue;
 299                         }
 300                         if ( $this->getFlip( $context ) ) {
 301                                 $style = CSSJanus::transform( $style, true, false );
 302                         }
 303                         $style = MemoizedCallable::call( 'CSSMin::remap',
 304                                 [ $style, false, $this->getConfig()->get( 'ScriptPath' ), true ] );
 305                         if ( !isset( $styles[$media] ) ) {
 306                                 $styles[$media] = [];
 307                         }
 308                         $style = ResourceLoader::makeComment( $titleText ) . $style;
 309                         $styles[$media][] = $style;
 310                 }
 311                 return $styles;
 312         }
 313
 314         /**
 315          * Disable module content versioning.
 316          *
 317          * This class does not support generating content outside of a module
 318          * request due to foreign database support.
 319          *
 320          * See getDefinitionSummary() for meta-data versioning.
 321          *
 322          * @return bool
 323          */
 324         public function enableModuleContentVersion() {
 325                 return false;
 326         }
 327
 328         /**
 329          * @param ResourceLoaderContext $context
 330          * @return array
 331          */
 332         public function getDefinitionSummary( ResourceLoaderContext $context ) {
 333                 $summary = parent::getDefinitionSummary( $context );
 334                 $summary[] = [
 335                         'pages' => $this->getPages( $context ),
 336                         // Includes meta data of current revisions
 337                         'titleInfo' => $this->getTitleInfo( $context ),
 338                 ];
 339                 return $summary;
 340         }
 341
 342         /**
 343          * @param ResourceLoaderContext $context
 344          * @return bool
 345          */
 346         public function isKnownEmpty( ResourceLoaderContext $context ) {
 347                 $revisions = $this->getTitleInfo( $context );
 348
 349                 // If a module has dependencies it cannot be empty. An empty array will be cast to false
 350                 if ( $this->getDependencies() ) {
 351                         return false;
 352                 }
 353                 // For user modules, don't needlessly load if there are no non-empty pages
 354                 if ( $this->getGroup() === 'user' ) {
 355                         foreach ( $revisions as $revision ) {
 356                                 if ( $revision['page_len'] > 0 ) {
 357                                         // At least one non-empty page, module should be loaded
 358                                         return false;
 359                                 }
 360                         }
 361                         return true;
 362                 }
 363
 364                 // T70488: For other modules (i.e. ones that are called in cached html output) only check
 365                 // page existance. This ensures that, if some pages in a module are temporarily blanked,
 366                 // we don't end omit the module's script or link tag on some pages.
 367                 return count( $revisions ) === 0;
 368         }
 369
 370         private function setTitleInfo( $batchKey, array $titleInfo ) {
 371                 $this->titleInfo[$batchKey] = $titleInfo;
 372         }
 373
 374         private static function makeTitleKey( LinkTarget $title ) {
 375                 // Used for keys in titleInfo.
 376                 return "{$title->getNamespace()}:{$title->getDBkey()}";
 377         }
 378
 379         /**
 380          * Get the information about the wiki pages for a given context.
 381          * @param ResourceLoaderContext $context
 382          * @return array Keyed by page name
 383          */
 384         protected function getTitleInfo( ResourceLoaderContext $context ) {
 385                 $dbr = $this->getDB();
 386
 387                 $pageNames = array_keys( $this->getPages( $context ) );
 388                 sort( $pageNames );
 389                 $batchKey = implode( '|', $pageNames );
 390                 if ( !isset( $this->titleInfo[$batchKey] ) ) {
 391                         $this->titleInfo[$batchKey] = static::fetchTitleInfo( $dbr, $pageNames, __METHOD__ );
 392                 }
 393
 394                 $titleInfo = $this->titleInfo[$batchKey];
 395
 396                 // Override the title info from the overrides, if any
 397                 $overrideCallback = $context->getContentOverrideCallback();
 398                 if ( $overrideCallback ) {
 399                         foreach ( $pageNames as $page ) {
 400                                 $title = Title::newFromText( $page );
 401                                 $content = $title ? call_user_func( $overrideCallback, $title ) : null;
 402                                 if ( $content !== null ) {
 403                                         $titleInfo[$title->getPrefixedText()] = [
 404                                                 'page_len' => $content->getSize(),
 405                                                 'page_latest' => 'TBD', // None available
 406                                                 'page_touched' => wfTimestamp( TS_MW ),
 407                                         ];
 408                                 }
 409                         }
 410                 }
 411
 412                 return $titleInfo;
 413         }
 414
 415         protected static function fetchTitleInfo( IDatabase $db, array $pages, $fname = __METHOD__ ) {
 416                 $titleInfo = [];
 417                 $batch = new LinkBatch;
 418                 foreach ( $pages as $titleText ) {
 419                         $title = Title::newFromText( $titleText );
 420                         if ( $title ) {
 421                                 // Page name may be invalid if user-provided (e.g. gadgets)
 422                                 $batch->addObj( $title );
 423                         }
 424                 }
 425                 if ( !$batch->isEmpty() ) {
 426                         $res = $db->select( 'page',
 427                                 // Include page_touched to allow purging if cache is poisoned (T117587, T113916)
 428                                 [ 'page_namespace', 'page_title', 'page_touched', 'page_len', 'page_latest' ],
 429                                 $batch->constructSet( 'page', $db ),
 430                                 $fname
 431                         );
 432                         foreach ( $res as $row ) {
 433                                 // Avoid including ids or timestamps of revision/page tables so
 434                                 // that versions are not wasted
 435                                 $title = new TitleValue( (int)$row->page_namespace, $row->page_title );
 436                                 $titleInfo[self::makeTitleKey( $title )] = [
 437                                         'page_len' => $row->page_len,
 438                                         'page_latest' => $row->page_latest,
 439                                         'page_touched' => $row->page_touched,
 440                                 ];
 441                         }
 442                 }
 443                 return $titleInfo;
 444         }
 445
 446         /**
 447          * @since 1.28
 448          * @param ResourceLoaderContext $context
 449          * @param IDatabase $db
 450          * @param string[] $moduleNames
 451          */
 452         public static function preloadTitleInfo(
 453                 ResourceLoaderContext $context, IDatabase $db, array $moduleNames
 454         ) {
 455                 $rl = $context->getResourceLoader();
 456                 // getDB() can be overridden to point to a foreign database.
 457                 // For now, only preload local. In the future, we could preload by wikiID.
 458                 $allPages = [];
 459                 /** @var ResourceLoaderWikiModule[] $wikiModules */
 460                 $wikiModules = [];
 461                 foreach ( $moduleNames as $name ) {
 462                         $module = $rl->getModule( $name );
 463                         if ( $module instanceof self ) {
 464                                 $mDB = $module->getDB();
 465                                 // Subclasses may implement getDB differently
 466                                 if ( $mDB->getDomainID() === $db->getDomainID() ) {
 467                                         $wikiModules[] = $module;
 468                                         $allPages += $module->getPages( $context );
 469                                 }
 470                         }
 471                 }
 472
 473                 if ( !$wikiModules ) {
 474                         // Nothing to preload
 475                         return;
 476                 }
 477
 478                 $pageNames = array_keys( $allPages );
 479                 sort( $pageNames );
 480                 $hash = sha1( implode( '|', $pageNames ) );
 481
 482                 // Avoid Zend bug where "static::" does not apply LSB in the closure
 483                 $func = [ static::class, 'fetchTitleInfo' ];
 484                 $fname = __METHOD__;
 485
 486                 $cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
 487                 $allInfo = $cache->getWithSetCallback(
 488                         $cache->makeGlobalKey( 'resourceloader-titleinfo', $db->getDomainID(), $hash ),
 489                         $cache::TTL_HOUR,
 490                         function ( $curVal, &$ttl, array &$setOpts ) use ( $func, $pageNames, $db, $fname ) {
 491                                 $setOpts += Database::getCacheSetOptions( $db );
 492
 493                                 return call_user_func( $func, $db, $pageNames, $fname );
 494                         },
 495                         [
 496                                 'checkKeys' => [
 497                                         $cache->makeGlobalKey( 'resourceloader-titleinfo', $db->getDomainID() ) ]
 498                         ]
 499                 );
 500
 501                 foreach ( $wikiModules as $wikiModule ) {
 502                         $pages = $wikiModule->getPages( $context );
 503                         // Before we intersect, map the names to canonical form (T145673).
 504                         $intersect = [];
 505                         foreach ( $pages as $pageName => $unused ) {
 506                                 $title = Title::newFromText( $pageName );
 507                                 if ( $title ) {
 508                                         $intersect[ self::makeTitleKey( $title ) ] = 1;
 509                                 } else {
 510                                         // Page name may be invalid if user-provided (e.g. gadgets)
 511                                         $rl->getLogger()->info(
 512                                                 'Invalid wiki page title "{title}" in ' . __METHOD__,
 513                                                 [ 'title' => $pageName ]
 514                                         );
 515                                 }
 516                         }
 517                         $info = array_intersect_key( $allInfo, $intersect );
 518                         $pageNames = array_keys( $pages );
 519                         sort( $pageNames );
 520                         $batchKey = implode( '|', $pageNames );
 521                         $wikiModule->setTitleInfo( $batchKey, $info );
 522                 }
 523         }
 524
 525         /**
 526          * Clear the preloadTitleInfo() cache for all wiki modules on this wiki on
 527          * page change if it was a JS or CSS page
 528          *
 529          * @param Title $title
 530          * @param Revision|null $old Prior page revision
 531          * @param Revision|null $new New page revision
 532          * @param string $domain Database domain ID
 533          * @since 1.28
 534          */
 535         public static function invalidateModuleCache(
 536                 Title $title, Revision $old = null, Revision $new = null, $domain
 537         ) {
 538                 static $formats = [ CONTENT_FORMAT_CSS, CONTENT_FORMAT_JAVASCRIPT ];
 539
 540                 Assert::parameterType( 'string', $domain, '$domain' );
 541
 542                 // TODO: MCR: differentiate between page functionality and content model!
 543                 //       Not all pages containing CSS or JS have to be modules! [PageType]
 544                 if ( $old && in_array( $old->getContentFormat(), $formats ) ) {
 545                         $purge = true;
 546                 } elseif ( $new && in_array( $new->getContentFormat(), $formats ) ) {
 547                         $purge = true;
 548                 } else {
 549                         $purge = ( $title->isSiteConfigPage() || $title->isUserConfigPage() );
 550                 }
 551
 552                 if ( $purge ) {
 553                         $cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
 554                         $key = $cache->makeGlobalKey( 'resourceloader-titleinfo', $domain );
 555                         $cache->touchCheckKey( $key );
 556                 }
 557         }
 558
 559         /**
 560          * @since 1.28
 561          * @return string
 562          */
 563         public function getType() {
 564                 // Check both because subclasses don't always pass pages via the constructor,
 565                 // they may also override getPages() instead, in which case we should keep
 566                 // defaulting to LOAD_GENERAL and allow them to override getType() separately.
 567                 return ( $this->styles && !$this->scripts ) ? self::LOAD_STYLES : self::LOAD_GENERAL;
 568         }
 569 }