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