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 Wikimedia\Rdbms\IDatabase;
  26
  27 /**
  28  * Abstraction for ResourceLoader modules which pull from wiki pages
  29  *
  30  * This can only be used for wiki pages in the MediaWiki and User namespaces,
  31  * because of its dependence on the functionality of Title::isCssJsSubpage
  32  * and Title::isCssOrJsPage().
  33  *
  34  * This module supports being used as a placeholder for a module on a remote wiki.
  35  * To do so, getDB() must be overloaded to return a foreign database object that
  36  * allows local wikis to query page metadata.
  37  *
  38  * Safe for calls on local wikis are:
  39  * - Option getters:
  40  *   - getGroup()
  41  *   - getPages()
  42  * - Basic methods that strictly involve the foreign database
  43  *   - getDB()
  44  *   - isKnownEmpty()
  45  *   - getTitleInfo()
  46  */
  47 class ResourceLoaderWikiModule extends ResourceLoaderModule {
  48
  49         // Origin defaults to users with sitewide authority
  50         protected $origin = self::ORIGIN_USER_SITEWIDE;
  51
  52         // In-process cache for title info
  53         protected $titleInfo = [];
  54
  55         // List of page names that contain CSS
  56         protected $styles = [];
  57
  58         // List of page names that contain JavaScript
  59         protected $scripts = [];
  60
  61         // Group of module
  62         protected $group;
  63
  64         /**
  65          * @param array $options For back-compat, this can be omitted in favour of overwriting getPages.
  66          */
  67         public function __construct( array $options = null ) {
  68                 if ( is_null( $options ) ) {
  69                         return;
  70                 }
  71
  72                 foreach ( $options as $member => $option ) {
  73                         switch ( $member ) {
  74                                 case 'styles':
  75                                 case 'scripts':
  76                                 case 'group':
  77                                 case 'targets':
  78                                         $this->{$member} = $option;
  79                                         break;
  80                         }
  81                 }
  82         }
  83
  84         /**
  85          * Subclasses should return an associative array of resources in the module.
  86          * Keys should be the title of a page in the MediaWiki or User namespace.
  87          *
  88          * Values should be a nested array of options.  The supported keys are 'type' and
  89          * (CSS only) 'media'.
  90          *
  91          * For scripts, 'type' should be 'script'.
  92          *
  93          * For stylesheets, 'type' should be 'style'.
  94          * There is an optional media key, the value of which can be the
  95          * medium ('screen', 'print', etc.) of the stylesheet.
  96          *
  97          * @param ResourceLoaderContext $context
  98          * @return array
  99          */
 100         protected function getPages( ResourceLoaderContext $context ) {
 101                 $config = $this->getConfig();
 102                 $pages = [];
 103
 104                 // Filter out pages from origins not allowed by the current wiki configuration.
 105                 if ( $config->get( 'UseSiteJs' ) ) {
 106                         foreach ( $this->scripts as $script ) {
 107                                 $pages[$script] = [ 'type' => 'script' ];
 108                         }
 109                 }
 110
 111                 if ( $config->get( 'UseSiteCss' ) ) {
 112                         foreach ( $this->styles as $style ) {
 113                                 $pages[$style] = [ 'type' => 'style' ];
 114                         }
 115                 }
 116
 117                 return $pages;
 118         }
 119
 120         /**
 121          * Get group name
 122          *
 123          * @return string
 124          */
 125         public function getGroup() {
 126                 return $this->group;
 127         }
 128
 129         /**
 130          * Get the Database object used in getTitleInfo().
 131          *
 132          * Defaults to the local replica DB. Subclasses may want to override this to return a foreign
 133          * database object, or null if getTitleInfo() shouldn't access the database.
 134          *
 135          * NOTE: This ONLY works for getTitleInfo() and isKnownEmpty(), NOT FOR ANYTHING ELSE.
 136          * In particular, it doesn't work for getContent() or getScript() etc.
 137          *
 138          * @return IDatabase|null
 139          */
 140         protected function getDB() {
 141                 return wfGetDB( DB_REPLICA );
 142         }
 143
 144         /**
 145          * @param string $titleText
 146          * @return null|string
 147          */
 148         protected function getContent( $titleText ) {
 149                 $title = Title::newFromText( $titleText );
 150                 if ( !$title ) {
 151                         return null;
 152                 }
 153
 154                 // If the page is a redirect, follow the redirect.
 155                 if ( $title->isRedirect() ) {
 156                         $content = $this->getContentObj( $title );
 157                         $title = $content ? $content->getUltimateRedirectTarget() : null;
 158                         if ( !$title ) {
 159                                 return null;
 160                         }
 161                 }
 162
 163                 $handler = ContentHandler::getForTitle( $title );
 164                 if ( $handler->isSupportedFormat( CONTENT_FORMAT_CSS ) ) {
 165                         $format = CONTENT_FORMAT_CSS;
 166                 } elseif ( $handler->isSupportedFormat( CONTENT_FORMAT_JAVASCRIPT ) ) {
 167                         $format = CONTENT_FORMAT_JAVASCRIPT;
 168                 } else {
 169                         return null;
 170                 }
 171
 172                 $content = $this->getContentObj( $title );
 173                 if ( !$content ) {
 174                         return null;
 175                 }
 176
 177                 return $content->serialize( $format );
 178         }
 179
 180         /**
 181          * @param Title $title
 182          * @return Content|null
 183          */
 184         protected function getContentObj( Title $title ) {
 185                 $revision = Revision::newKnownCurrent( wfGetDB( DB_REPLICA ), $title->getArticleID(),
 186                         $title->getLatestRevID() );
 187                 if ( !$revision ) {
 188                         return null;
 189                 }
 190                 $revision->setTitle( $title );
 191                 $content = $revision->getContent( Revision::RAW );
 192                 if ( !$content ) {
 193                         wfDebugLog( 'resourceloader', __METHOD__ . ': failed to load content of JS/CSS page!' );
 194                         return null;
 195                 }
 196                 return $content;
 197         }
 198
 199         /**
 200          * @param ResourceLoaderContext $context
 201          * @return string
 202          */
 203         public function getScript( ResourceLoaderContext $context ) {
 204                 $scripts = '';
 205                 foreach ( $this->getPages( $context ) as $titleText => $options ) {
 206                         if ( $options['type'] !== 'script' ) {
 207                                 continue;
 208                         }
 209                         $script = $this->getContent( $titleText );
 210                         if ( strval( $script ) !== '' ) {
 211                                 $script = $this->validateScriptFile( $titleText, $script );
 212                                 $scripts .= ResourceLoader::makeComment( $titleText ) . $script . "\n";
 213                         }
 214                 }
 215                 return $scripts;
 216         }
 217
 218         /**
 219          * @param ResourceLoaderContext $context
 220          * @return array
 221          */
 222         public function getStyles( ResourceLoaderContext $context ) {
 223                 $styles = [];
 224                 foreach ( $this->getPages( $context ) as $titleText => $options ) {
 225                         if ( $options['type'] !== 'style' ) {
 226                                 continue;
 227                         }
 228                         $media = isset( $options['media'] ) ? $options['media'] : 'all';
 229                         $style = $this->getContent( $titleText );
 230                         if ( strval( $style ) === '' ) {
 231                                 continue;
 232                         }
 233                         if ( $this->getFlip( $context ) ) {
 234                                 $style = CSSJanus::transform( $style, true, false );
 235                         }
 236                         $style = MemoizedCallable::call( 'CSSMin::remap',
 237                                 [ $style, false, $this->getConfig()->get( 'ScriptPath' ), true ] );
 238                         if ( !isset( $styles[$media] ) ) {
 239                                 $styles[$media] = [];
 240                         }
 241                         $style = ResourceLoader::makeComment( $titleText ) . $style;
 242                         $styles[$media][] = $style;
 243                 }
 244                 return $styles;
 245         }
 246
 247         /**
 248          * Disable module content versioning.
 249          *
 250          * This class does not support generating content outside of a module
 251          * request due to foreign database support.
 252          *
 253          * See getDefinitionSummary() for meta-data versioning.
 254          *
 255          * @return bool
 256          */
 257         public function enableModuleContentVersion() {
 258                 return false;
 259         }
 260
 261         /**
 262          * @param ResourceLoaderContext $context
 263          * @return array
 264          */
 265         public function getDefinitionSummary( ResourceLoaderContext $context ) {
 266                 $summary = parent::getDefinitionSummary( $context );
 267                 $summary[] = [
 268                         'pages' => $this->getPages( $context ),
 269                         // Includes meta data of current revisions
 270                         'titleInfo' => $this->getTitleInfo( $context ),
 271                 ];
 272                 return $summary;
 273         }
 274
 275         /**
 276          * @param ResourceLoaderContext $context
 277          * @return bool
 278          */
 279         public function isKnownEmpty( ResourceLoaderContext $context ) {
 280                 $revisions = $this->getTitleInfo( $context );
 281
 282                 // For user modules, don't needlessly load if there are no non-empty pages
 283                 if ( $this->getGroup() === 'user' ) {
 284                         foreach ( $revisions as $revision ) {
 285                                 if ( $revision['page_len'] > 0 ) {
 286                                         // At least one non-empty page, module should be loaded
 287                                         return false;
 288                                 }
 289                         }
 290                         return true;
 291                 }
 292
 293                 // T70488: For other modules (i.e. ones that are called in cached html output) only check
 294                 // page existance. This ensures that, if some pages in a module are temporarily blanked,
 295                 // we don't end omit the module's script or link tag on some pages.
 296                 return count( $revisions ) === 0;
 297         }
 298
 299         private function setTitleInfo( $key, array $titleInfo ) {
 300                 $this->titleInfo[$key] = $titleInfo;
 301         }
 302
 303         /**
 304          * Get the information about the wiki pages for a given context.
 305          * @param ResourceLoaderContext $context
 306          * @return array Keyed by page name
 307          */
 308         protected function getTitleInfo( ResourceLoaderContext $context ) {
 309                 $dbr = $this->getDB();
 310                 if ( !$dbr ) {
 311                         // We're dealing with a subclass that doesn't have a DB
 312                         return [];
 313                 }
 314
 315                 $pageNames = array_keys( $this->getPages( $context ) );
 316                 sort( $pageNames );
 317                 $key = implode( '|', $pageNames );
 318                 if ( !isset( $this->titleInfo[$key] ) ) {
 319                         $this->titleInfo[$key] = static::fetchTitleInfo( $dbr, $pageNames, __METHOD__ );
 320                 }
 321                 return $this->titleInfo[$key];
 322         }
 323
 324         protected static function fetchTitleInfo( IDatabase $db, array $pages, $fname = __METHOD__ ) {
 325                 $titleInfo = [];
 326                 $batch = new LinkBatch;
 327                 foreach ( $pages as $titleText ) {
 328                         $title = Title::newFromText( $titleText );
 329                         if ( $title ) {
 330                                 // Page name may be invalid if user-provided (e.g. gadgets)
 331                                 $batch->addObj( $title );
 332                         }
 333                 }
 334                 if ( !$batch->isEmpty() ) {
 335                         $res = $db->select( 'page',
 336                                 // Include page_touched to allow purging if cache is poisoned (T117587, T113916)
 337                                 [ 'page_namespace', 'page_title', 'page_touched', 'page_len', 'page_latest' ],
 338                                 $batch->constructSet( 'page', $db ),
 339                                 $fname
 340                         );
 341                         foreach ( $res as $row ) {
 342                                 // Avoid including ids or timestamps of revision/page tables so
 343                                 // that versions are not wasted
 344                                 $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 345                                 $titleInfo[$title->getPrefixedText()] = [
 346                                         'page_len' => $row->page_len,
 347                                         'page_latest' => $row->page_latest,
 348                                         'page_touched' => $row->page_touched,
 349                                 ];
 350                         }
 351                 }
 352                 return $titleInfo;
 353         }
 354
 355         /**
 356          * @since 1.28
 357          * @param ResourceLoaderContext $context
 358          * @param IDatabase $db
 359          * @param string[] $moduleNames
 360          */
 361         public static function preloadTitleInfo(
 362                 ResourceLoaderContext $context, IDatabase $db, array $moduleNames
 363         ) {
 364                 $rl = $context->getResourceLoader();
 365                 // getDB() can be overridden to point to a foreign database.
 366                 // For now, only preload local. In the future, we could preload by wikiID.
 367                 $allPages = [];
 368                 /** @var ResourceLoaderWikiModule[] $wikiModules */
 369                 $wikiModules = [];
 370                 foreach ( $moduleNames as $name ) {
 371                         $module = $rl->getModule( $name );
 372                         if ( $module instanceof self ) {
 373                                 $mDB = $module->getDB();
 374                                 // Subclasses may disable getDB and implement getTitleInfo differently
 375                                 if ( $mDB && $mDB->getWikiID() === $db->getWikiID() ) {
 376                                         $wikiModules[] = $module;
 377                                         $allPages += $module->getPages( $context );
 378                                 }
 379                         }
 380                 }
 381
 382                 if ( !$wikiModules ) {
 383                         // Nothing to preload
 384                         return;
 385                 }
 386
 387                 $pageNames = array_keys( $allPages );
 388                 sort( $pageNames );
 389                 $hash = sha1( implode( '|', $pageNames ) );
 390
 391                 // Avoid Zend bug where "static::" does not apply LSB in the closure
 392                 $func = [ static::class, 'fetchTitleInfo' ];
 393                 $fname = __METHOD__;
 394
 395                 $cache = ObjectCache::getMainWANInstance();
 396                 $allInfo = $cache->getWithSetCallback(
 397                         $cache->makeGlobalKey( 'resourceloader', 'titleinfo', $db->getWikiID(), $hash ),
 398                         $cache::TTL_HOUR,
 399                         function ( $curVal, &$ttl, array &$setOpts ) use ( $func, $pageNames, $db, $fname ) {
 400                                 $setOpts += Database::getCacheSetOptions( $db );
 401
 402                                 return call_user_func( $func, $db, $pageNames, $fname );
 403                         },
 404                         [ 'checkKeys' => [ $cache->makeGlobalKey( 'resourceloader', 'titleinfo', $db->getWikiID() ) ] ]
 405                 );
 406
 407                 foreach ( $wikiModules as $wikiModule ) {
 408                         $pages = $wikiModule->getPages( $context );
 409                         // Before we intersect, map the names to canonical form (T145673).
 410                         $intersect = [];
 411                         foreach ( $pages as $page => $unused ) {
 412                                 $title = Title::newFromText( $page );
 413                                 if ( $title ) {
 414                                         $intersect[ $title->getPrefixedText() ] = 1;
 415                                 } else {
 416                                         // Page name may be invalid if user-provided (e.g. gadgets)
 417                                         $rl->getLogger()->info(
 418                                                 'Invalid wiki page title "{title}" in ' . __METHOD__,
 419                                                 [ 'title' => $page ]
 420                                         );
 421                                 }
 422                         }
 423                         $info = array_intersect_key( $allInfo, $intersect );
 424                         $pageNames = array_keys( $pages );
 425                         sort( $pageNames );
 426                         $key = implode( '|', $pageNames );
 427                         $wikiModule->setTitleInfo( $key, $info );
 428                 }
 429         }
 430
 431         /**
 432          * Clear the preloadTitleInfo() cache for all wiki modules on this wiki on
 433          * page change if it was a JS or CSS page
 434          *
 435          * @param Title $title
 436          * @param Revision|null $old Prior page revision
 437          * @param Revision|null $new New page revision
 438          * @param string $wikiId
 439          * @since 1.28
 440          */
 441         public static function invalidateModuleCache(
 442                 Title $title, Revision $old = null, Revision $new = null, $wikiId
 443         ) {
 444                 static $formats = [ CONTENT_FORMAT_CSS, CONTENT_FORMAT_JAVASCRIPT ];
 445
 446                 if ( $old && in_array( $old->getContentFormat(), $formats ) ) {
 447                         $purge = true;
 448                 } elseif ( $new && in_array( $new->getContentFormat(), $formats ) ) {
 449                         $purge = true;
 450                 } else {
 451                         $purge = ( $title->isCssOrJsPage() || $title->isCssJsSubpage() );
 452                 }
 453
 454                 if ( $purge ) {
 455                         $cache = ObjectCache::getMainWANInstance();
 456                         $key = $cache->makeGlobalKey( 'resourceloader', 'titleinfo', $wikiId );
 457                         $cache->touchCheckKey( $key );
 458                 }
 459         }
 460
 461         /**
 462          * @since 1.28
 463          * @return string
 464          */
 465         public function getType() {
 466                 // Check both because subclasses don't always pass pages via the constructor,
 467                 // they may also override getPages() instead, in which case we should keep
 468                 // defaulting to LOAD_GENERAL and allow them to override getType() separately.
 469                 return ( $this->styles && !$this->scripts ) ? self::LOAD_STYLES : self::LOAD_GENERAL;
 470         }
 471 }