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Diffstat (limited to 'www/wiki/includes/resourceloader/ResourceLoaderModule.php')
| -rw-r--r-- | www/wiki/includes/resourceloader/ResourceLoaderModule.php | 1044 |
1 files changed, 1044 insertions, 0 deletions
diff --git a/www/wiki/includes/resourceloader/ResourceLoaderModule.php b/www/wiki/includes/resourceloader/ResourceLoaderModule.php new file mode 100644 index 00000000..2abc17c2 --- /dev/null +++ b/www/wiki/includes/resourceloader/ResourceLoaderModule.php @@ -0,0 +1,1044 @@ +<?php +/** + * Abstraction for ResourceLoader modules. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * http://www.gnu.org/copyleft/gpl.html + * + * @file + * @author Trevor Parscal + * @author Roan Kattouw + */ + +use MediaWiki\MediaWikiServices; +use Psr\Log\LoggerAwareInterface; +use Psr\Log\LoggerInterface; +use Psr\Log\NullLogger; +use Wikimedia\RelPath; +use Wikimedia\ScopedCallback; + +/** + * Abstraction for ResourceLoader modules, with name registration and maxage functionality. + */ +abstract class ResourceLoaderModule implements LoggerAwareInterface { + # Type of resource + const TYPE_SCRIPTS = 'scripts'; + const TYPE_STYLES = 'styles'; + const TYPE_COMBINED = 'combined'; + + # Desired load type + // Module only has styles (loaded via <style> or <link rel=stylesheet>) + const LOAD_STYLES = 'styles'; + // Module may have other resources (loaded via mw.loader from a script) + const LOAD_GENERAL = 'general'; + + # sitewide core module like a skin file or jQuery component + const ORIGIN_CORE_SITEWIDE = 1; + + # per-user module generated by the software + const ORIGIN_CORE_INDIVIDUAL = 2; + + # sitewide module generated from user-editable files, like MediaWiki:Common.js, or + # modules accessible to multiple users, such as those generated by the Gadgets extension. + const ORIGIN_USER_SITEWIDE = 3; + + # per-user module generated from user-editable files, like User:Me/vector.js + const ORIGIN_USER_INDIVIDUAL = 4; + + # an access constant; make sure this is kept as the largest number in this group + const ORIGIN_ALL = 10; + + # script and style modules form a hierarchy of trustworthiness, with core modules like + # skins and jQuery as most trustworthy, and user scripts as least trustworthy. We can + # limit the types of scripts and styles we allow to load on, say, sensitive special + # pages like Special:UserLogin and Special:Preferences + protected $origin = self::ORIGIN_CORE_SITEWIDE; + + protected $name = null; + protected $targets = [ 'desktop' ]; + + // In-object cache for file dependencies + protected $fileDeps = []; + // In-object cache for message blob (keyed by language) + protected $msgBlobs = []; + // In-object cache for version hash + protected $versionHash = []; + // In-object cache for module content + protected $contents = []; + + /** + * @var Config + */ + protected $config; + + /** + * @var array|bool + */ + protected $deprecated = false; + + /** + * @var LoggerInterface + */ + protected $logger; + + /** + * Get this module's name. This is set when the module is registered + * with ResourceLoader::register() + * + * @return string|null Name (string) or null if no name was set + */ + public function getName() { + return $this->name; + } + + /** + * Set this module's name. This is called by ResourceLoader::register() + * when registering the module. Other code should not call this. + * + * @param string $name + */ + public function setName( $name ) { + $this->name = $name; + } + + /** + * Get this module's origin. This is set when the module is registered + * with ResourceLoader::register() + * + * @return int ResourceLoaderModule class constant, the subclass default + * if not set manually + */ + public function getOrigin() { + return $this->origin; + } + + /** + * @param ResourceLoaderContext $context + * @return bool + */ + public function getFlip( $context ) { + global $wgContLang; + + return $wgContLang->getDir() !== $context->getDirection(); + } + + /** + * Get JS representing deprecation information for the current module if available + * + * @return string JavaScript code + */ + protected function getDeprecationInformation() { + $deprecationInfo = $this->deprecated; + if ( $deprecationInfo ) { + $name = $this->getName(); + $warning = 'This page is using the deprecated ResourceLoader module "' . $name . '".'; + if ( is_string( $deprecationInfo ) ) { + $warning .= "\n" . $deprecationInfo; + } + return Xml::encodeJsCall( + 'mw.log.warn', + [ $warning ] + ); + } else { + return ''; + } + } + + /** + * Get all JS for this module for a given language and skin. + * Includes all relevant JS except loader scripts. + * + * @param ResourceLoaderContext $context + * @return string JavaScript code + */ + public function getScript( ResourceLoaderContext $context ) { + // Stub, override expected + return ''; + } + + /** + * Takes named templates by the module and returns an array mapping. + * + * @return array of templates mapping template alias to content + */ + public function getTemplates() { + // Stub, override expected. + return []; + } + + /** + * @return Config + * @since 1.24 + */ + public function getConfig() { + if ( $this->config === null ) { + // Ugh, fall back to default + $this->config = MediaWikiServices::getInstance()->getMainConfig(); + } + + return $this->config; + } + + /** + * @param Config $config + * @since 1.24 + */ + public function setConfig( Config $config ) { + $this->config = $config; + } + + /** + * @since 1.27 + * @param LoggerInterface $logger + * @return null + */ + public function setLogger( LoggerInterface $logger ) { + $this->logger = $logger; + } + + /** + * @since 1.27 + * @return LoggerInterface + */ + protected function getLogger() { + if ( !$this->logger ) { + $this->logger = new NullLogger(); + } + return $this->logger; + } + + /** + * Get the URL or URLs to load for this module's JS in debug mode. + * The default behavior is to return a load.php?only=scripts URL for + * the module, but file-based modules will want to override this to + * load the files directly. + * + * This function is called only when 1) we're in debug mode, 2) there + * is no only= parameter and 3) supportsURLLoading() returns true. + * #2 is important to prevent an infinite loop, therefore this function + * MUST return either an only= URL or a non-load.php URL. + * + * @param ResourceLoaderContext $context + * @return array Array of URLs + */ + public function getScriptURLsForDebug( ResourceLoaderContext $context ) { + $resourceLoader = $context->getResourceLoader(); + $derivative = new DerivativeResourceLoaderContext( $context ); + $derivative->setModules( [ $this->getName() ] ); + $derivative->setOnly( 'scripts' ); + $derivative->setDebug( true ); + + $url = $resourceLoader->createLoaderURL( + $this->getSource(), + $derivative + ); + + return [ $url ]; + } + + /** + * Whether this module supports URL loading. If this function returns false, + * getScript() will be used even in cases (debug mode, no only param) where + * getScriptURLsForDebug() would normally be used instead. + * @return bool + */ + public function supportsURLLoading() { + return true; + } + + /** + * Get all CSS for this module for a given skin. + * + * @param ResourceLoaderContext $context + * @return array List of CSS strings or array of CSS strings keyed by media type. + * like [ 'screen' => '.foo { width: 0 }' ]; + * or [ 'screen' => [ '.foo { width: 0 }' ] ]; + */ + public function getStyles( ResourceLoaderContext $context ) { + // Stub, override expected + return []; + } + + /** + * Get the URL or URLs to load for this module's CSS in debug mode. + * The default behavior is to return a load.php?only=styles URL for + * the module, but file-based modules will want to override this to + * load the files directly. See also getScriptURLsForDebug() + * + * @param ResourceLoaderContext $context + * @return array [ mediaType => [ URL1, URL2, ... ], ... ] + */ + public function getStyleURLsForDebug( ResourceLoaderContext $context ) { + $resourceLoader = $context->getResourceLoader(); + $derivative = new DerivativeResourceLoaderContext( $context ); + $derivative->setModules( [ $this->getName() ] ); + $derivative->setOnly( 'styles' ); + $derivative->setDebug( true ); + + $url = $resourceLoader->createLoaderURL( + $this->getSource(), + $derivative + ); + + return [ 'all' => [ $url ] ]; + } + + /** + * Get the messages needed for this module. + * + * To get a JSON blob with messages, use MessageBlobStore::get() + * + * @return array List of message keys. Keys may occur more than once + */ + public function getMessages() { + // Stub, override expected + return []; + } + + /** + * Get the group this module is in. + * + * @return string Group name + */ + public function getGroup() { + // Stub, override expected + return null; + } + + /** + * Get the origin of this module. Should only be overridden for foreign modules. + * + * @return string Origin name, 'local' for local modules + */ + public function getSource() { + // Stub, override expected + return 'local'; + } + + /** + * Whether this module's JS expects to work without the client-side ResourceLoader module. + * Returning true from this function will prevent mw.loader.state() call from being + * appended to the bottom of the script. + * + * @return bool + */ + public function isRaw() { + return false; + } + + /** + * Get a list of modules this module depends on. + * + * Dependency information is taken into account when loading a module + * on the client side. + * + * Note: It is expected that $context will be made non-optional in the near + * future. + * + * @param ResourceLoaderContext $context + * @return array List of module names as strings + */ + public function getDependencies( ResourceLoaderContext $context = null ) { + // Stub, override expected + return []; + } + + /** + * Get target(s) for the module, eg ['desktop'] or ['desktop', 'mobile'] + * + * @return array Array of strings + */ + public function getTargets() { + return $this->targets; + } + + /** + * Get the module's load type. + * + * @since 1.28 + * @return string ResourceLoaderModule LOAD_* constant + */ + public function getType() { + return self::LOAD_GENERAL; + } + + /** + * Get the skip function. + * + * Modules that provide fallback functionality can provide a "skip function". This + * function, if provided, will be passed along to the module registry on the client. + * When this module is loaded (either directly or as a dependency of another module), + * then this function is executed first. If the function returns true, the module will + * instantly be considered "ready" without requesting the associated module resources. + * + * The value returned here must be valid javascript for execution in a private function. + * It must not contain the "function () {" and "}" wrapper though. + * + * @return string|null A JavaScript function body returning a boolean value, or null + */ + public function getSkipFunction() { + return null; + } + + /** + * Get the files this module depends on indirectly for a given skin. + * + * These are only image files referenced by the module's stylesheet. + * + * @param ResourceLoaderContext $context + * @return array List of files + */ + protected function getFileDependencies( ResourceLoaderContext $context ) { + $vary = $context->getSkin() . '|' . $context->getLanguage(); + + // Try in-object cache first + if ( !isset( $this->fileDeps[$vary] ) ) { + $dbr = wfGetDB( DB_REPLICA ); + $deps = $dbr->selectField( 'module_deps', + 'md_deps', + [ + 'md_module' => $this->getName(), + 'md_skin' => $vary, + ], + __METHOD__ + ); + + if ( !is_null( $deps ) ) { + $this->fileDeps[$vary] = self::expandRelativePaths( + (array)FormatJson::decode( $deps, true ) + ); + } else { + $this->fileDeps[$vary] = []; + } + } + return $this->fileDeps[$vary]; + } + + /** + * Set in-object cache for file dependencies. + * + * This is used to retrieve data in batches. See ResourceLoader::preloadModuleInfo(). + * To save the data, use saveFileDependencies(). + * + * @param ResourceLoaderContext $context + * @param string[] $files Array of file names + */ + public function setFileDependencies( ResourceLoaderContext $context, $files ) { + $vary = $context->getSkin() . '|' . $context->getLanguage(); + $this->fileDeps[$vary] = $files; + } + + /** + * Set the files this module depends on indirectly for a given skin. + * + * @since 1.27 + * @param ResourceLoaderContext $context + * @param array $localFileRefs List of files + */ + protected function saveFileDependencies( ResourceLoaderContext $context, $localFileRefs ) { + try { + // Related bugs and performance considerations: + // 1. Don't needlessly change the database value with the same list in a + // different order or with duplicates. + // 2. Use relative paths to avoid ghost entries when $IP changes. (T111481) + // 3. Don't needlessly replace the database with the same value + // just because $IP changed (e.g. when upgrading a wiki). + // 4. Don't create an endless replace loop on every request for this + // module when '../' is used anywhere. Even though both are expanded + // (one expanded by getFileDependencies from the DB, the other is + // still raw as originally read by RL), the latter has not + // been normalized yet. + + // Normalise + $localFileRefs = array_values( array_unique( $localFileRefs ) ); + sort( $localFileRefs ); + $localPaths = self::getRelativePaths( $localFileRefs ); + + $storedPaths = self::getRelativePaths( $this->getFileDependencies( $context ) ); + // If the list has been modified since last time we cached it, update the cache + if ( $localPaths !== $storedPaths ) { + $vary = $context->getSkin() . '|' . $context->getLanguage(); + $cache = ObjectCache::getLocalClusterInstance(); + $key = $cache->makeKey( __METHOD__, $this->getName(), $vary ); + $scopeLock = $cache->getScopedLock( $key, 0 ); + if ( !$scopeLock ) { + return; // T124649; avoid write slams + } + + $deps = FormatJson::encode( $localPaths ); + $dbw = wfGetDB( DB_MASTER ); + $dbw->upsert( 'module_deps', + [ + 'md_module' => $this->getName(), + 'md_skin' => $vary, + 'md_deps' => $deps, + ], + [ [ 'md_module', 'md_skin' ] ], + [ + 'md_deps' => $deps, + ] + ); + + if ( $dbw->trxLevel() ) { + $dbw->onTransactionResolution( + function () use ( &$scopeLock ) { + ScopedCallback::consume( $scopeLock ); // release after commit + }, + __METHOD__ + ); + } + } + } catch ( Exception $e ) { + wfDebugLog( 'resourceloader', __METHOD__ . ": failed to update DB: $e" ); + } + } + + /** + * Make file paths relative to MediaWiki directory. + * + * This is used to make file paths safe for storing in a database without the paths + * becoming stale or incorrect when MediaWiki is moved or upgraded (T111481). + * + * @since 1.27 + * @param array $filePaths + * @return array + */ + public static function getRelativePaths( array $filePaths ) { + global $IP; + return array_map( function ( $path ) use ( $IP ) { + return RelPath::getRelativePath( $path, $IP ); + }, $filePaths ); + } + + /** + * Expand directories relative to $IP. + * + * @since 1.27 + * @param array $filePaths + * @return array + */ + public static function expandRelativePaths( array $filePaths ) { + global $IP; + return array_map( function ( $path ) use ( $IP ) { + return RelPath::joinPath( $IP, $path ); + }, $filePaths ); + } + + /** + * Get the hash of the message blob. + * + * @since 1.27 + * @param ResourceLoaderContext $context + * @return string|null JSON blob or null if module has no messages + */ + protected function getMessageBlob( ResourceLoaderContext $context ) { + if ( !$this->getMessages() ) { + // Don't bother consulting MessageBlobStore + return null; + } + // Message blobs may only vary language, not by context keys + $lang = $context->getLanguage(); + if ( !isset( $this->msgBlobs[$lang] ) ) { + $this->getLogger()->warning( 'Message blob for {module} should have been preloaded', [ + 'module' => $this->getName(), + ] ); + $store = $context->getResourceLoader()->getMessageBlobStore(); + $this->msgBlobs[$lang] = $store->getBlob( $this, $lang ); + } + return $this->msgBlobs[$lang]; + } + + /** + * Set in-object cache for message blobs. + * + * Used to allow fetching of message blobs in batches. See ResourceLoader::preloadModuleInfo(). + * + * @since 1.27 + * @param string|null $blob JSON blob or null + * @param string $lang Language code + */ + public function setMessageBlob( $blob, $lang ) { + $this->msgBlobs[$lang] = $blob; + } + + /** + * Get headers to send as part of a module web response. + * + * It is not supported to send headers through this method that are + * required to be unique or otherwise sent once in an HTTP response + * because clients may make batch requests for multiple modules (as + * is the default behaviour for ResourceLoader clients). + * + * For exclusive or aggregated headers, see ResourceLoader::sendResponseHeaders(). + * + * @since 1.30 + * @param ResourceLoaderContext $context + * @return string[] Array of HTTP response headers + */ + final public function getHeaders( ResourceLoaderContext $context ) { + $headers = []; + + $formattedLinks = []; + foreach ( $this->getPreloadLinks( $context ) as $url => $attribs ) { + $link = "<{$url}>;rel=preload"; + foreach ( $attribs as $key => $val ) { + $link .= ";{$key}={$val}"; + } + $formattedLinks[] = $link; + } + if ( $formattedLinks ) { + $headers[] = 'Link: ' . implode( ',', $formattedLinks ); + } + + return $headers; + } + + /** + * Get a list of resources that web browsers may preload. + * + * Behaviour of rel=preload link is specified at <https://www.w3.org/TR/preload/>. + * + * Use case for ResourceLoader originally part of T164299. + * + * @par Example + * @code + * protected function getPreloadLinks() { + * return [ + * 'https://example.org/script.js' => [ 'as' => 'script' ], + * 'https://example.org/image.png' => [ 'as' => 'image' ], + * ]; + * } + * @endcode + * + * @par Example using HiDPI image variants + * @code + * protected function getPreloadLinks() { + * return [ + * 'https://example.org/logo.png' => [ + * 'as' => 'image', + * 'media' => 'not all and (min-resolution: 2dppx)', + * ], + * 'https://example.org/logo@2x.png' => [ + * 'as' => 'image', + * 'media' => '(min-resolution: 2dppx)', + * ], + * ]; + * } + * @endcode + * + * @see ResourceLoaderModule::getHeaders + * @since 1.30 + * @param ResourceLoaderContext $context + * @return array Keyed by url, values must be an array containing + * at least an 'as' key. Optionally a 'media' key as well. + */ + protected function getPreloadLinks( ResourceLoaderContext $context ) { + return []; + } + + /** + * Get module-specific LESS variables, if any. + * + * @since 1.27 + * @param ResourceLoaderContext $context + * @return array Module-specific LESS variables. + */ + protected function getLessVars( ResourceLoaderContext $context ) { + return []; + } + + /** + * Get an array of this module's resources. Ready for serving to the web. + * + * @since 1.26 + * @param ResourceLoaderContext $context + * @return array + */ + public function getModuleContent( ResourceLoaderContext $context ) { + $contextHash = $context->getHash(); + // Cache this expensive operation. This calls builds the scripts, styles, and messages + // content which typically involves filesystem and/or database access. + if ( !array_key_exists( $contextHash, $this->contents ) ) { + $this->contents[$contextHash] = $this->buildContent( $context ); + } + return $this->contents[$contextHash]; + } + + /** + * Bundle all resources attached to this module into an array. + * + * @since 1.26 + * @param ResourceLoaderContext $context + * @return array + */ + final protected function buildContent( ResourceLoaderContext $context ) { + $rl = $context->getResourceLoader(); + $stats = MediaWikiServices::getInstance()->getStatsdDataFactory(); + $statStart = microtime( true ); + + // Only include properties that are relevant to this context (e.g. only=scripts) + // and that are non-empty (e.g. don't include "templates" for modules without + // templates). This helps prevent invalidating cache for all modules when new + // optional properties are introduced. + $content = []; + + // Scripts + if ( $context->shouldIncludeScripts() ) { + // If we are in debug mode, we'll want to return an array of URLs if possible + // However, we can't do this if the module doesn't support it + // We also can't do this if there is an only= parameter, because we have to give + // the module a way to return a load.php URL without causing an infinite loop + if ( $context->getDebug() && !$context->getOnly() && $this->supportsURLLoading() ) { + $scripts = $this->getScriptURLsForDebug( $context ); + } else { + $scripts = $this->getScript( $context ); + // Make the script safe to concatenate by making sure there is at least one + // trailing new line at the end of the content. Previously, this looked for + // a semi-colon instead, but that breaks concatenation if the semicolon + // is inside a comment like "// foo();". Instead, simply use a + // line break as separator which matches JavaScript native logic for implicitly + // ending statements even if a semi-colon is missing. + // Bugs: T29054, T162719. + if ( is_string( $scripts ) + && strlen( $scripts ) + && substr( $scripts, -1 ) !== "\n" + ) { + $scripts .= "\n"; + } + } + $content['scripts'] = $scripts; + } + + // Styles + if ( $context->shouldIncludeStyles() ) { + $styles = []; + // Don't create empty stylesheets like [ '' => '' ] for modules + // that don't *have* any stylesheets (T40024). + $stylePairs = $this->getStyles( $context ); + if ( count( $stylePairs ) ) { + // If we are in debug mode without &only= set, we'll want to return an array of URLs + // See comment near shouldIncludeScripts() for more details + if ( $context->getDebug() && !$context->getOnly() && $this->supportsURLLoading() ) { + $styles = [ + 'url' => $this->getStyleURLsForDebug( $context ) + ]; + } else { + // Minify CSS before embedding in mw.loader.implement call + // (unless in debug mode) + if ( !$context->getDebug() ) { + foreach ( $stylePairs as $media => $style ) { + // Can be either a string or an array of strings. + if ( is_array( $style ) ) { + $stylePairs[$media] = []; + foreach ( $style as $cssText ) { + if ( is_string( $cssText ) ) { + $stylePairs[$media][] = + ResourceLoader::filter( 'minify-css', $cssText ); + } + } + } elseif ( is_string( $style ) ) { + $stylePairs[$media] = ResourceLoader::filter( 'minify-css', $style ); + } + } + } + // Wrap styles into @media groups as needed and flatten into a numerical array + $styles = [ + 'css' => $rl->makeCombinedStyles( $stylePairs ) + ]; + } + } + $content['styles'] = $styles; + } + + // Messages + $blob = $this->getMessageBlob( $context ); + if ( $blob ) { + $content['messagesBlob'] = $blob; + } + + $templates = $this->getTemplates(); + if ( $templates ) { + $content['templates'] = $templates; + } + + $headers = $this->getHeaders( $context ); + if ( $headers ) { + $content['headers'] = $headers; + } + + $statTiming = microtime( true ) - $statStart; + $statName = strtr( $this->getName(), '.', '_' ); + $stats->timing( "resourceloader_build.all", 1000 * $statTiming ); + $stats->timing( "resourceloader_build.$statName", 1000 * $statTiming ); + + return $content; + } + + /** + * Get a string identifying the current version of this module in a given context. + * + * Whenever anything happens that changes the module's response (e.g. scripts, styles, and + * messages) this value must change. This value is used to store module responses in cache. + * (Both client-side and server-side.) + * + * It is not recommended to override this directly. Use getDefinitionSummary() instead. + * If overridden, one must call the parent getVersionHash(), append data and re-hash. + * + * This method should be quick because it is frequently run by ResourceLoaderStartUpModule to + * propagate changes to the client and effectively invalidate cache. + * + * For backward-compatibility, the following optional data providers are automatically included: + * + * - getModifiedTime() + * - getModifiedHash() + * + * @since 1.26 + * @param ResourceLoaderContext $context + * @return string Hash (should use ResourceLoader::makeHash) + */ + public function getVersionHash( ResourceLoaderContext $context ) { + // The startup module produces a manifest with versions representing the entire module. + // Typically, the request for the startup module itself has only=scripts. That must apply + // only to the startup module content, and not to the module version computed here. + $context = new DerivativeResourceLoaderContext( $context ); + $context->setModules( [] ); + // Version hash must cover all resources, regardless of startup request itself. + $context->setOnly( null ); + // Compute version hash based on content, not debug urls. + $context->setDebug( false ); + + // Cache this somewhat expensive operation. Especially because some classes + // (e.g. startup module) iterate more than once over all modules to get versions. + $contextHash = $context->getHash(); + if ( !array_key_exists( $contextHash, $this->versionHash ) ) { + if ( $this->enableModuleContentVersion() ) { + // Detect changes directly + $str = json_encode( $this->getModuleContent( $context ) ); + } else { + // Infer changes based on definition and other metrics + $summary = $this->getDefinitionSummary( $context ); + if ( !isset( $summary['_cacheEpoch'] ) ) { + throw new LogicException( 'getDefinitionSummary must call parent method' ); + } + $str = json_encode( $summary ); + + $mtime = $this->getModifiedTime( $context ); + if ( $mtime !== null ) { + // Support: MediaWiki 1.25 and earlier + $str .= strval( $mtime ); + } + + $mhash = $this->getModifiedHash( $context ); + if ( $mhash !== null ) { + // Support: MediaWiki 1.25 and earlier + $str .= strval( $mhash ); + } + } + + $this->versionHash[$contextHash] = ResourceLoader::makeHash( $str ); + } + return $this->versionHash[$contextHash]; + } + + /** + * Whether to generate version hash based on module content. + * + * If a module requires database or file system access to build the module + * content, consider disabling this in favour of manually tracking relevant + * aspects in getDefinitionSummary(). See getVersionHash() for how this is used. + * + * @return bool + */ + public function enableModuleContentVersion() { + return false; + } + + /** + * Get the definition summary for this module. + * + * This is the method subclasses are recommended to use to track values in their + * version hash. Call this in getVersionHash() and pass it to e.g. json_encode. + * + * Subclasses must call the parent getDefinitionSummary() and build on that. + * It is recommended that each subclass appends its own new array. This prevents + * clashes or accidental overwrites of existing keys and gives each subclass + * its own scope for simple array keys. + * + * @code + * $summary = parent::getDefinitionSummary( $context ); + * $summary[] = [ + * 'foo' => 123, + * 'bar' => 'quux', + * ]; + * return $summary; + * @endcode + * + * Return an array containing values from all significant properties of this + * module's definition. + * + * Be careful not to normalise too much. Especially preserve the order of things + * that carry significance in getScript and getStyles (T39812). + * + * Avoid including things that are insiginificant (e.g. order of message keys is + * insignificant and should be sorted to avoid unnecessary cache invalidation). + * + * This data structure must exclusively contain arrays and scalars as values (avoid + * object instances) to allow simple serialisation using json_encode. + * + * If modules have a hash or timestamp from another source, that may be incuded as-is. + * + * A number of utility methods are available to help you gather data. These are not + * called by default and must be included by the subclass' getDefinitionSummary(). + * + * - getMessageBlob() + * + * @since 1.23 + * @param ResourceLoaderContext $context + * @return array|null + */ + public function getDefinitionSummary( ResourceLoaderContext $context ) { + return [ + '_class' => static::class, + '_cacheEpoch' => $this->getConfig()->get( 'CacheEpoch' ), + ]; + } + + /** + * Get this module's last modification timestamp for a given context. + * + * @deprecated since 1.26 Use getDefinitionSummary() instead + * @param ResourceLoaderContext $context + * @return int|null UNIX timestamp + */ + public function getModifiedTime( ResourceLoaderContext $context ) { + return null; + } + + /** + * Helper method for providing a version hash to getVersionHash(). + * + * @deprecated since 1.26 Use getDefinitionSummary() instead + * @param ResourceLoaderContext $context + * @return string|null Hash + */ + public function getModifiedHash( ResourceLoaderContext $context ) { + return null; + } + + /** + * Check whether this module is known to be empty. If a child class + * has an easy and cheap way to determine that this module is + * definitely going to be empty, it should override this method to + * return true in that case. Callers may optimize the request for this + * module away if this function returns true. + * @param ResourceLoaderContext $context + * @return bool + */ + public function isKnownEmpty( ResourceLoaderContext $context ) { + return false; + } + + /** + * Check whether this module should be embeded rather than linked + * + * Modules returning true here will be embedded rather than loaded by + * ResourceLoaderClientHtml. + * + * @since 1.30 + * @param ResourceLoaderContext $context + * @return bool + */ + public function shouldEmbedModule( ResourceLoaderContext $context ) { + return $this->getGroup() === 'private'; + } + + /** @var JSParser Lazy-initialized; use self::javaScriptParser() */ + private static $jsParser; + private static $parseCacheVersion = 1; + + /** + * Validate a given script file; if valid returns the original source. + * If invalid, returns replacement JS source that throws an exception. + * + * @param string $fileName + * @param string $contents + * @return string JS with the original, or a replacement error + */ + protected function validateScriptFile( $fileName, $contents ) { + if ( !$this->getConfig()->get( 'ResourceLoaderValidateJS' ) ) { + return $contents; + } + $cache = ObjectCache::getMainWANInstance(); + return $cache->getWithSetCallback( + $cache->makeGlobalKey( + 'resourceloader', + 'jsparse', + self::$parseCacheVersion, + md5( $contents ), + $fileName + ), + $cache::TTL_WEEK, + function () use ( $contents, $fileName ) { + $parser = self::javaScriptParser(); + try { + $parser->parse( $contents, $fileName, 1 ); + $result = $contents; + } catch ( Exception $e ) { + // We'll save this to cache to avoid having to re-validate broken JS + $err = $e->getMessage(); + $result = "mw.log.error(" . + Xml::encodeJsVar( "JavaScript parse error: $err" ) . ");"; + } + return $result; + } + ); + } + + /** + * @return JSParser + */ + protected static function javaScriptParser() { + if ( !self::$jsParser ) { + self::$jsParser = new JSParser(); + } + return self::$jsParser; + } + + /** + * Safe version of filemtime(), which doesn't throw a PHP warning if the file doesn't exist. + * Defaults to 1. + * + * @param string $filePath File path + * @return int UNIX timestamp + */ + protected static function safeFilemtime( $filePath ) { + Wikimedia\suppressWarnings(); + $mtime = filemtime( $filePath ) ?: 1; + Wikimedia\restoreWarnings(); + return $mtime; + } + + /** + * Compute a non-cryptographic string hash of a file's contents. + * If the file does not exist or cannot be read, returns an empty string. + * + * @since 1.26 Uses MD4 instead of SHA1. + * @param string $filePath File path + * @return string Hash + */ + protected static function safeFileHash( $filePath ) { + return FileContentsHasher::getFileContentsHash( $filePath ); + } +} |