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 /**
  26  * Abstraction for ResourceLoader modules which pull from wiki pages
  27  *
  28  * This can only be used for wiki pages in the MediaWiki and User namespaces,
  29  * because of its dependence on the functionality of Title::isCssJsSubpage
  30  * and Title::isCssOrJsPage().
  31  *
  32  * This module supports being used as a placeholder for a module on a remote wiki.
  33  * To do so, getDB() must be overloaded to return a foreign database object that
  34  * allows local wikis to query page metadata.
  35  *
  36  * Safe for calls on local wikis are:
  37  * - Option getters:
  38  *   - getGroup()
  39  *   - getPosition()
  40  *   - getPages()
  41  * - Basic methods that strictly involve the foreign database
  42  *   - getDB()
  43  *   - isKnownEmpty()
  44  *   - getTitleInfo()
  45  */
  46 class ResourceLoaderWikiModule extends ResourceLoaderModule {
  47         /** @var string Position on the page to load this module at */
  48         protected $position = 'bottom';
  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 'position':
  76                                 case 'styles':
  77                                 case 'scripts':
  78                                 case 'group':
  79                                 case 'targets':
  80                                         $this->{$member} = $option;
  81                                         break;
  82                         }
  83                 }
  84         }
  85
  86         /**
  87          * Subclasses should return an associative array of resources in the module.
  88          * Keys should be the title of a page in the MediaWiki or User namespace.
  89          *
  90          * Values should be a nested array of options.  The supported keys are 'type' and
  91          * (CSS only) 'media'.
  92          *
  93          * For scripts, 'type' should be 'script'.
  94          *
  95          * For stylesheets, 'type' should be 'style'.
  96          * There is an optional media key, the value of which can be the
  97          * medium ('screen', 'print', etc.) of the stylesheet.
  98          *
  99          * @param ResourceLoaderContext $context
 100          * @return array
 101          */
 102         protected function getPages( ResourceLoaderContext $context ) {
 103                 $config = $this->getConfig();
 104                 $pages = [];
 105
 106                 // Filter out pages from origins not allowed by the current wiki configuration.
 107                 if ( $config->get( 'UseSiteJs' ) ) {
 108                         foreach ( $this->scripts as $script ) {
 109                                 $pages[$script] = [ 'type' => 'script' ];
 110                         }
 111                 }
 112
 113                 if ( $config->get( 'UseSiteCss' ) ) {
 114                         foreach ( $this->styles as $style ) {
 115                                 $pages[$style] = [ 'type' => 'style' ];
 116                         }
 117                 }
 118
 119                 return $pages;
 120         }
 121
 122         /**
 123          * Get group name
 124          *
 125          * @return string
 126          */
 127         public function getGroup() {
 128                 return $this->group;
 129         }
 130
 131         /**
 132          * Get the Database object used in getTitleInfo().
 133          *
 134          * Defaults to the local replica DB. Subclasses may want to override this to return a foreign
 135          * database object, or null if getTitleInfo() shouldn't access the database.
 136          *
 137          * NOTE: This ONLY works for getTitleInfo() and isKnownEmpty(), NOT FOR ANYTHING ELSE.
 138          * In particular, it doesn't work for getContent() or getScript() etc.
 139          *
 140          * @return IDatabase|null
 141          */
 142         protected function getDB() {
 143                 return wfGetDB( DB_REPLICA );
 144         }
 145
 146         /**
 147          * @param string $titleText
 148          * @return null|string
 149          */
 150         protected function getContent( $titleText ) {
 151                 $title = Title::newFromText( $titleText );
 152                 if ( !$title ) {
 153                         return null;
 154                 }
 155
 156                 $handler = ContentHandler::getForTitle( $title );
 157                 if ( $handler->isSupportedFormat( CONTENT_FORMAT_CSS ) ) {
 158                         $format = CONTENT_FORMAT_CSS;
 159                 } elseif ( $handler->isSupportedFormat( CONTENT_FORMAT_JAVASCRIPT ) ) {
 160                         $format = CONTENT_FORMAT_JAVASCRIPT;
 161                 } else {
 162                         return null;
 163                 }
 164
 165                 $revision = Revision::newFromTitle( $title, false, Revision::READ_NORMAL );
 166                 if ( !$revision ) {
 167                         return null;
 168                 }
 169
 170                 $content = $revision->getContent( Revision::RAW );
 171
 172                 if ( !$content ) {
 173                         wfDebugLog( 'resourceloader', __METHOD__ . ': failed to load content of JS/CSS page!' );
 174                         return null;
 175                 }
 176
 177                 return $content->serialize( $format );
 178         }
 179
 180         /**
 181          * @param ResourceLoaderContext $context
 182          * @return string
 183          */
 184         public function getScript( ResourceLoaderContext $context ) {
 185                 $scripts = '';
 186                 foreach ( $this->getPages( $context ) as $titleText => $options ) {
 187                         if ( $options['type'] !== 'script' ) {
 188                                 continue;
 189                         }
 190                         $script = $this->getContent( $titleText );
 191                         if ( strval( $script ) !== '' ) {
 192                                 $script = $this->validateScriptFile( $titleText, $script );
 193                                 $scripts .= ResourceLoader::makeComment( $titleText ) . $script . "\n";
 194                         }
 195                 }
 196                 return $scripts;
 197         }
 198
 199         /**
 200          * @param ResourceLoaderContext $context
 201          * @return array
 202          */
 203         public function getStyles( ResourceLoaderContext $context ) {
 204                 $styles = [];
 205                 foreach ( $this->getPages( $context ) as $titleText => $options ) {
 206                         if ( $options['type'] !== 'style' ) {
 207                                 continue;
 208                         }
 209                         $media = isset( $options['media'] ) ? $options['media'] : 'all';
 210                         $style = $this->getContent( $titleText );
 211                         if ( strval( $style ) === '' ) {
 212                                 continue;
 213                         }
 214                         if ( $this->getFlip( $context ) ) {
 215                                 $style = CSSJanus::transform( $style, true, false );
 216                         }
 217                         $style = MemoizedCallable::call( 'CSSMin::remap',
 218                                 [ $style, false, $this->getConfig()->get( 'ScriptPath' ), true ] );
 219                         if ( !isset( $styles[$media] ) ) {
 220                                 $styles[$media] = [];
 221                         }
 222                         $style = ResourceLoader::makeComment( $titleText ) . $style;
 223                         $styles[$media][] = $style;
 224                 }
 225                 return $styles;
 226         }
 227
 228         /**
 229          * Disable module content versioning.
 230          *
 231          * This class does not support generating content outside of a module
 232          * request due to foreign database support.
 233          *
 234          * See getDefinitionSummary() for meta-data versioning.
 235          *
 236          * @return bool
 237          */
 238         public function enableModuleContentVersion() {
 239                 return false;
 240         }
 241
 242         /**
 243          * @param ResourceLoaderContext $context
 244          * @return array
 245          */
 246         public function getDefinitionSummary( ResourceLoaderContext $context ) {
 247                 $summary = parent::getDefinitionSummary( $context );
 248                 $summary[] = [
 249                         'pages' => $this->getPages( $context ),
 250                         // Includes meta data of current revisions
 251                         'titleInfo' => $this->getTitleInfo( $context ),
 252                 ];
 253                 return $summary;
 254         }
 255
 256         /**
 257          * @param ResourceLoaderContext $context
 258          * @return bool
 259          */
 260         public function isKnownEmpty( ResourceLoaderContext $context ) {
 261                 $revisions = $this->getTitleInfo( $context );
 262
 263                 // For user modules, don't needlessly load if there are no non-empty pages
 264                 if ( $this->getGroup() === 'user' ) {
 265                         foreach ( $revisions as $revision ) {
 266                                 if ( $revision['page_len'] > 0 ) {
 267                                         // At least one non-empty page, module should be loaded
 268                                         return false;
 269                                 }
 270                         }
 271                         return true;
 272                 }
 273
 274                 // Bug 68488: For other modules (i.e. ones that are called in cached html output) only check
 275                 // page existance. This ensures that, if some pages in a module are temporarily blanked,
 276                 // we don't end omit the module's script or link tag on some pages.
 277                 return count( $revisions ) === 0;
 278         }
 279
 280         private function setTitleInfo( $key, array $titleInfo ) {
 281                 $this->titleInfo[$key] = $titleInfo;
 282         }
 283
 284         /**
 285          * Get the information about the wiki pages for a given context.
 286          * @param ResourceLoaderContext $context
 287          * @return array Keyed by page name
 288          */
 289         protected function getTitleInfo( ResourceLoaderContext $context ) {
 290                 $dbr = $this->getDB();
 291                 if ( !$dbr ) {
 292                         // We're dealing with a subclass that doesn't have a DB
 293                         return [];
 294                 }
 295
 296                 $pageNames = array_keys( $this->getPages( $context ) );
 297                 sort( $pageNames );
 298                 $key = implode( '|', $pageNames );
 299                 if ( !isset( $this->titleInfo[$key] ) ) {
 300                         $this->titleInfo[$key] = static::fetchTitleInfo( $dbr, $pageNames, __METHOD__ );
 301                 }
 302                 return $this->titleInfo[$key];
 303         }
 304
 305         protected static function fetchTitleInfo( IDatabase $db, array $pages, $fname = __METHOD__ ) {
 306                 $titleInfo = [];
 307                 $batch = new LinkBatch;
 308                 foreach ( $pages as $titleText ) {
 309                         $title = Title::newFromText( $titleText );
 310                         if ( $title ) {
 311                                 // Page name may be invalid if user-provided (e.g. gadgets)
 312                                 $batch->addObj( $title );
 313                         }
 314                 }
 315                 if ( !$batch->isEmpty() ) {
 316                         $res = $db->select( 'page',
 317                                 // Include page_touched to allow purging if cache is poisoned (T117587, T113916)
 318                                 [ 'page_namespace', 'page_title', 'page_touched', 'page_len', 'page_latest' ],
 319                                 $batch->constructSet( 'page', $db ),
 320                                 $fname
 321                         );
 322                         foreach ( $res as $row ) {
 323                                 // Avoid including ids or timestamps of revision/page tables so
 324                                 // that versions are not wasted
 325                                 $title = Title::makeTitle( $row->page_namespace, $row->page_title );
 326                                 $titleInfo[$title->getPrefixedText()] = [
 327                                         'page_len' => $row->page_len,
 328                                         'page_latest' => $row->page_latest,
 329                                         'page_touched' => $row->page_touched,
 330                                 ];
 331                         }
 332                 }
 333                 return $titleInfo;
 334         }
 335
 336         /**
 337          * @since 1.28
 338          * @param ResourceLoaderContext $context
 339          * @param IDatabase $db
 340          * @param string[] $moduleNames
 341          */
 342         public static function preloadTitleInfo(
 343                 ResourceLoaderContext $context, IDatabase $db, array $moduleNames
 344         ) {
 345                 $rl = $context->getResourceLoader();
 346                 // getDB() can be overridden to point to a foreign database.
 347                 // For now, only preload local. In the future, we could preload by wikiID.
 348                 $allPages = [];
 349                 /** @var ResourceLoaderWikiModule[] $wikiModules */
 350                 $wikiModules = [];
 351                 foreach ( $moduleNames as $name ) {
 352                         $module = $rl->getModule( $name );
 353                         if ( $module instanceof self ) {
 354                                 $mDB = $module->getDB();
 355                                 // Subclasses may disable getDB and implement getTitleInfo differently
 356                                 if ( $mDB && $mDB->getWikiID() === $db->getWikiID() ) {
 357                                         $wikiModules[] = $module;
 358                                         $allPages += $module->getPages( $context );
 359                                 }
 360                         }
 361                 }
 362
 363                 $pageNames = array_keys( $allPages );
 364                 sort( $pageNames );
 365                 $hash = sha1( implode( '|', $pageNames ) );
 366
 367                 // Avoid Zend bug where "static::" does not apply LSB in the closure
 368                 $func = [ static::class, 'fetchTitleInfo' ];
 369                 $fname = __METHOD__;
 370
 371                 $cache = ObjectCache::getMainWANInstance();
 372                 $allInfo = $cache->getWithSetCallback(
 373                         $cache->makeGlobalKey( 'resourceloader', 'titleinfo', $db->getWikiID(), $hash ),
 374                         $cache::TTL_HOUR,
 375                         function ( $curVal, &$ttl, array &$setOpts ) use ( $func, $pageNames, $db, $fname ) {
 376                                 $setOpts += Database::getCacheSetOptions( $db );
 377
 378                                 return call_user_func( $func, $db, $pageNames, $fname );
 379                         },
 380                         [ 'checkKeys' => [ $cache->makeGlobalKey( 'resourceloader', 'titleinfo', $db->getWikiID() ) ] ]
 381                 );
 382
 383                 foreach ( $wikiModules as $wikiModule ) {
 384                         $pages = $wikiModule->getPages( $context );
 385                         // Before we intersect, map the names to canonical form (T145673).
 386                         $intersect = [];
 387                         foreach ( $pages as $page => $unused ) {
 388                                 $title = Title::newFromText( $page );
 389                                 if ( $title ) {
 390                                         $intersect[ $title->getPrefixedText() ] = 1;
 391                                 } else {
 392                                         // Page name may be invalid if user-provided (e.g. gadgets)
 393                                         $rl->getLogger()->info(
 394                                                 'Invalid wiki page title "{title}" in ' . __METHOD__,
 395                                                 [ 'title' => $page ]
 396                                         );
 397                                 }
 398                         }
 399                         $info = array_intersect_key( $allInfo, $intersect );
 400                         $pageNames = array_keys( $pages );
 401                         sort( $pageNames );
 402                         $key = implode( '|', $pageNames );
 403                         $wikiModule->setTitleInfo( $key, $info );
 404                 }
 405         }
 406
 407         /**
 408          * Clear the preloadTitleInfo() cache for all wiki modules on this wiki on
 409          * page change if it was a JS or CSS page
 410          *
 411          * @param Title $title
 412          * @param Revision|null $old Prior page revision
 413          * @param Revision|null $new New page revision
 414          * @param string $wikiId
 415          * @since 1.28
 416          */
 417         public static function invalidateModuleCache(
 418                 Title $title, Revision $old = null, Revision $new = null, $wikiId
 419         ) {
 420                 static $formats = [ CONTENT_FORMAT_CSS, CONTENT_FORMAT_JAVASCRIPT ];
 421
 422                 if ( $old && in_array( $old->getContentFormat(), $formats ) ) {
 423                         $purge = true;
 424                 } elseif ( $new && in_array( $new->getContentFormat(), $formats ) ) {
 425                         $purge = true;
 426                 } else {
 427                         $purge = ( $title->isCssOrJsPage() || $title->isCssJsSubpage() );
 428                 }
 429
 430                 if ( $purge ) {
 431                         $cache = ObjectCache::getMainWANInstance();
 432                         $key = $cache->makeGlobalKey( 'resourceloader', 'titleinfo', $wikiId );
 433                         $cache->touchCheckKey( $key );
 434                 }
 435         }
 436
 437         /**
 438          * @return string
 439          */
 440         public function getPosition() {
 441                 return $this->position;
 442         }
 443
 444         /**
 445          * @since 1.28
 446          * @return string
 447          */
 448         public function getType() {
 449                 // Check both because subclasses don't always pass pages via the constructor,
 450                 // they may also override getPages() instead, in which case we should keep
 451                 // defaulting to LOAD_GENERAL and allow them to override getType() separately.
 452                 return ( $this->styles && !$this->scripts ) ? self::LOAD_STYLES : self::LOAD_GENERAL;
 453         }
 454 }