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