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                 // For user modules, don't needlessly load if there are no non-empty pages
 295                 if ( $this->getGroup() === 'user' ) {
 296                         foreach ( $revisions as $revision ) {
 297                                 if ( $revision['page_len'] > 0 ) {
 298                                         // At least one non-empty page, module should be loaded
 299                                         return false;
 300                                 }
 301                         }
 302                         return true;
 303                 }
 304
 305                 // T70488: For other modules (i.e. ones that are called in cached html output) only check
 306                 // page existance. This ensures that, if some pages in a module are temporarily blanked,
 307                 // we don't end omit the module's script or link tag on some pages.
 308                 return count( $revisions ) === 0;
 309         }
 310
 311         private function setTitleInfo( $batchKey, array $titleInfo ) {
 312                 $this->titleInfo[$batchKey] = $titleInfo;
 313         }
 314
 315         private static function makeTitleKey( LinkTarget $title ) {
 316                 // Used for keys in titleInfo.
 317                 return "{$title->getNamespace()}:{$title->getDBkey()}";
 318         }
 319
 320         /**
 321          * Get the information about the wiki pages for a given context.
 322          * @param ResourceLoaderContext $context
 323          * @return array Keyed by page name
 324          */
 325         protected function getTitleInfo( ResourceLoaderContext $context ) {
 326                 $dbr = $this->getDB();
 327                 if ( !$dbr ) {
 328                         // We're dealing with a subclass that doesn't have a DB
 329                         return [];
 330                 }
 331
 332                 $pageNames = array_keys( $this->getPages( $context ) );
 333                 sort( $pageNames );
 334                 $batchKey = implode( '|', $pageNames );
 335                 if ( !isset( $this->titleInfo[$batchKey] ) ) {
 336                         $this->titleInfo[$batchKey] = static::fetchTitleInfo( $dbr, $pageNames, __METHOD__ );
 337                 }
 338                 return $this->titleInfo[$batchKey];
 339         }
 340
 341         protected static function fetchTitleInfo( IDatabase $db, array $pages, $fname = __METHOD__ ) {
 342                 $titleInfo = [];
 343                 $batch = new LinkBatch;
 344                 foreach ( $pages as $titleText ) {
 345                         $title = Title::newFromText( $titleText );
 346                         if ( $title ) {
 347                                 // Page name may be invalid if user-provided (e.g. gadgets)
 348                                 $batch->addObj( $title );
 349                         }
 350                 }
 351                 if ( !$batch->isEmpty() ) {
 352                         $res = $db->select( 'page',
 353                                 // Include page_touched to allow purging if cache is poisoned (T117587, T113916)
 354                                 [ 'page_namespace', 'page_title', 'page_touched', 'page_len', 'page_latest' ],
 355                                 $batch->constructSet( 'page', $db ),
 356                                 $fname
 357                         );
 358                         foreach ( $res as $row ) {
 359                                 // Avoid including ids or timestamps of revision/page tables so
 360                                 // that versions are not wasted
 361                                 $title = new TitleValue( (int)$row->page_namespace, $row->page_title );
 362                                 $titleInfo[ self::makeTitleKey( $title ) ] = [
 363                                         'page_len' => $row->page_len,
 364                                         'page_latest' => $row->page_latest,
 365                                         'page_touched' => $row->page_touched,
 366                                 ];
 367                         }
 368                 }
 369                 return $titleInfo;
 370         }
 371
 372         /**
 373          * @since 1.28
 374          * @param ResourceLoaderContext $context
 375          * @param IDatabase $db
 376          * @param string[] $moduleNames
 377          */
 378         public static function preloadTitleInfo(
 379                 ResourceLoaderContext $context, IDatabase $db, array $moduleNames
 380         ) {
 381                 $rl = $context->getResourceLoader();
 382                 // getDB() can be overridden to point to a foreign database.
 383                 // For now, only preload local. In the future, we could preload by wikiID.
 384                 $allPages = [];
 385                 /** @var ResourceLoaderWikiModule[] $wikiModules */
 386                 $wikiModules = [];
 387                 foreach ( $moduleNames as $name ) {
 388                         $module = $rl->getModule( $name );
 389                         if ( $module instanceof self ) {
 390                                 $mDB = $module->getDB();
 391                                 // Subclasses may disable getDB and implement getTitleInfo differently
 392                                 if ( $mDB && $mDB->getDomainID() === $db->getDomainID() ) {
 393                                         $wikiModules[] = $module;
 394                                         $allPages += $module->getPages( $context );
 395                                 }
 396                         }
 397                 }
 398
 399                 if ( !$wikiModules ) {
 400                         // Nothing to preload
 401                         return;
 402                 }
 403
 404                 $pageNames = array_keys( $allPages );
 405                 sort( $pageNames );
 406                 $hash = sha1( implode( '|', $pageNames ) );
 407
 408                 // Avoid Zend bug where "static::" does not apply LSB in the closure
 409                 $func = [ static::class, 'fetchTitleInfo' ];
 410                 $fname = __METHOD__;
 411
 412                 $cache = ObjectCache::getMainWANInstance();
 413                 $allInfo = $cache->getWithSetCallback(
 414                         $cache->makeGlobalKey( 'resourceloader', 'titleinfo', $db->getDomainID(), $hash ),
 415                         $cache::TTL_HOUR,
 416                         function ( $curVal, &$ttl, array &$setOpts ) use ( $func, $pageNames, $db, $fname ) {
 417                                 $setOpts += Database::getCacheSetOptions( $db );
 418
 419                                 return call_user_func( $func, $db, $pageNames, $fname );
 420                         },
 421                         [
 422                                 'checkKeys' => [
 423                                         $cache->makeGlobalKey( 'resourceloader', 'titleinfo', $db->getDomainID() ) ]
 424                         ]
 425                 );
 426
 427                 foreach ( $wikiModules as $wikiModule ) {
 428                         $pages = $wikiModule->getPages( $context );
 429                         // Before we intersect, map the names to canonical form (T145673).
 430                         $intersect = [];
 431                         foreach ( $pages as $pageName => $unused ) {
 432                                 $title = Title::newFromText( $pageName );
 433                                 if ( $title ) {
 434                                         $intersect[ self::makeTitleKey( $title ) ] = 1;
 435                                 } else {
 436                                         // Page name may be invalid if user-provided (e.g. gadgets)
 437                                         $rl->getLogger()->info(
 438                                                 'Invalid wiki page title "{title}" in ' . __METHOD__,
 439                                                 [ 'title' => $pageName ]
 440                                         );
 441                                 }
 442                         }
 443                         $info = array_intersect_key( $allInfo, $intersect );
 444                         $pageNames = array_keys( $pages );
 445                         sort( $pageNames );
 446                         $batchKey = implode( '|', $pageNames );
 447                         $wikiModule->setTitleInfo( $batchKey, $info );
 448                 }
 449         }
 450
 451         /**
 452          * Clear the preloadTitleInfo() cache for all wiki modules on this wiki on
 453          * page change if it was a JS or CSS page
 454          *
 455          * @param Title $title
 456          * @param Revision|null $old Prior page revision
 457          * @param Revision|null $new New page revision
 458          * @param string $wikiId
 459          * @since 1.28
 460          */
 461         public static function invalidateModuleCache(
 462                 Title $title, Revision $old = null, Revision $new = null, $wikiId
 463         ) {
 464                 static $formats = [ CONTENT_FORMAT_CSS, CONTENT_FORMAT_JAVASCRIPT ];
 465
 466                 if ( $old && in_array( $old->getContentFormat(), $formats ) ) {
 467                         $purge = true;
 468                 } elseif ( $new && in_array( $new->getContentFormat(), $formats ) ) {
 469                         $purge = true;
 470                 } else {
 471                         $purge = ( $title->isSiteConfigPage() || $title->isUserConfigPage() );
 472                 }
 473
 474                 if ( $purge ) {
 475                         $cache = ObjectCache::getMainWANInstance();
 476                         $key = $cache->makeGlobalKey( 'resourceloader', 'titleinfo', $wikiId );
 477                         $cache->touchCheckKey( $key );
 478                 }
 479         }
 480
 481         /**
 482          * @since 1.28
 483          * @return string
 484          */
 485         public function getType() {
 486                 // Check both because subclasses don't always pass pages via the constructor,
 487                 // they may also override getPages() instead, in which case we should keep
 488                 // defaulting to LOAD_GENERAL and allow them to override getType() separately.
 489                 return ( $this->styles && !$this->scripts ) ? self::LOAD_STYLES : self::LOAD_GENERAL;
 490         }
 491 }