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