includes/resourceloader/ResourceLoaderFileModule.php

   1 <?php
   2 /**
   3  * Resource loader module based on local JavaScript/CSS files.
   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  * ResourceLoader module based on local JavaScript/CSS files.
  27  */
  28 class ResourceLoaderFileModule extends ResourceLoaderModule {
  29
  30         /* Protected Members */
  31
  32         /** String: Local base path, see __construct() */
  33         protected $localBasePath = '';
  34         /** String: Remote base path, see __construct() */
  35         protected $remoteBasePath = '';
  36         /**
  37          * Array: List of paths to JavaScript files to always include
  38          * @par Usage:
  39          * @code
  40          * array( [file-path], [file-path], ... )
  41          * @endcode
  42          */
  43         protected $scripts = array();
  44         /**
  45          * Array: List of JavaScript files to include when using a specific language
  46          * @par Usage:
  47          * @code
  48          * array( [language-code] => array( [file-path], [file-path], ... ), ... )
  49          * @endcode
  50          */
  51         protected $languageScripts = array();
  52         /**
  53          * Array: List of JavaScript files to include when using a specific skin
  54          * @par Usage:
  55          * @code
  56          * array( [skin-name] => array( [file-path], [file-path], ... ), ... )
  57          * @endcode
  58          */
  59         protected $skinScripts = array();
  60         /**
  61          * Array: List of paths to JavaScript files to include in debug mode
  62          * @par Usage:
  63          * @code
  64          * array( [skin-name] => array( [file-path], [file-path], ... ), ... )
  65          * @endcode
  66          */
  67         protected $debugScripts = array();
  68         /**
  69          * Array: List of paths to JavaScript files to include in the startup module
  70          * @par Usage:
  71          * @code
  72          * array( [file-path], [file-path], ... )
  73          * @endcode
  74          */
  75         protected $loaderScripts = array();
  76         /**
  77          * Array: List of paths to CSS files to always include
  78          * @par Usage:
  79          * @code
  80          * array( [file-path], [file-path], ... )
  81          * @endcode
  82          */
  83         protected $styles = array();
  84         /**
  85          * Array: List of paths to CSS files to include when using specific skins
  86          * @par Usage:
  87          * @code
  88          * array( [file-path], [file-path], ... )
  89          * @endcode
  90          */
  91         protected $skinStyles = array();
  92         /**
  93          * Array: List of modules this module depends on
  94          * @par Usage:
  95          * @code
  96          * array( [file-path], [file-path], ... )
  97          * @endcode
  98          */
  99         protected $dependencies = array();
 100         /**
 101          * Array: List of message keys used by this module
 102          * @par Usage:
 103          * @code
 104          * array( [message-key], [message-key], ... )
 105          * @endcode
 106          */
 107         protected $messages = array();
 108         /** String: Name of group to load this module in */
 109         protected $group;
 110         /** String: Position on the page to load this module at */
 111         protected $position = 'bottom';
 112         /** Boolean: Link to raw files in debug mode */
 113         protected $debugRaw = true;
 114         /** Boolean: Whether mw.loader.state() call should be omitted */
 115         protected $raw = false;
 116         protected $targets = array( 'desktop' );
 117
 118         /**
 119          * Boolean: Whether getStyleURLsForDebug should return raw file paths,
 120          * or return load.php urls
 121          */
 122         protected $hasGeneratedStyles = false;
 123
 124         /**
 125          * Array: Cache for mtime
 126          * @par Usage:
 127          * @code
 128          * array( [hash] => [mtime], [hash] => [mtime], ... )
 129          * @endcode
 130          */
 131         protected $modifiedTime = array();
 132         /**
 133          * Array: Place where readStyleFile() tracks file dependencies
 134          * @par Usage:
 135          * @code
 136          * array( [file-path], [file-path], ... )
 137          * @endcode
 138          */
 139         protected $localFileRefs = array();
 140
 141         /* Methods */
 142
 143         /**
 144          * Constructs a new module from an options array.
 145          *
 146          * @param array $options List of options; if not given or empty, an empty module will be
 147          *     constructed
 148          * @param string $localBasePath Base path to prepend to all local paths in $options. Defaults
 149          *     to $IP
 150          * @param string $remoteBasePath Base path to prepend to all remote paths in $options. Defaults
 151          *     to $wgScriptPath
 152          *
 153          * Below is a description for the $options array:
 154          * @throws MWException
 155          * @par Construction options:
 156          * @code
 157          *     array(
 158          *         // Base path to prepend to all local paths in $options. Defaults to $IP
 159          *         'localBasePath' => [base path],
 160          *         // Base path to prepend to all remote paths in $options. Defaults to $wgScriptPath
 161          *         'remoteBasePath' => [base path],
 162          *         // Equivalent of remoteBasePath, but relative to $wgExtensionAssetsPath
 163          *         'remoteExtPath' => [base path],
 164          *         // Scripts to always include
 165          *         'scripts' => [file path string or array of file path strings],
 166          *         // Scripts to include in specific language contexts
 167          *         'languageScripts' => array(
 168          *             [language code] => [file path string or array of file path strings],
 169          *         ),
 170          *         // Scripts to include in specific skin contexts
 171          *         'skinScripts' => array(
 172          *             [skin name] => [file path string or array of file path strings],
 173          *         ),
 174          *         // Scripts to include in debug contexts
 175          *         'debugScripts' => [file path string or array of file path strings],
 176          *         // Scripts to include in the startup module
 177          *         'loaderScripts' => [file path string or array of file path strings],
 178          *         // Modules which must be loaded before this module
 179          *         'dependencies' => [module name string or array of module name strings],
 180          *         // Styles to always load
 181          *         'styles' => [file path string or array of file path strings],
 182          *         // Styles to include in specific skin contexts
 183          *         'skinStyles' => array(
 184          *             [skin name] => [file path string or array of file path strings],
 185          *         ),
 186          *         // Messages to always load
 187          *         'messages' => [array of message key strings],
 188          *         // Group which this module should be loaded together with
 189          *         'group' => [group name string],
 190          *         // Position on the page to load this module at
 191          *         'position' => ['bottom' (default) or 'top']
 192          *     )
 193          * @endcode
 194          */
 195         public function __construct( $options = array(), $localBasePath = null,
 196                 $remoteBasePath = null
 197         ) {
 198                 global $IP, $wgScriptPath, $wgResourceBasePath;
 199                 $this->localBasePath = $localBasePath === null ? $IP : $localBasePath;
 200                 if ( $remoteBasePath !== null ) {
 201                         $this->remoteBasePath = $remoteBasePath;
 202                 } else {
 203                         $this->remoteBasePath = $wgResourceBasePath === null ? $wgScriptPath : $wgResourceBasePath;
 204                 }
 205
 206                 if ( isset( $options['remoteExtPath'] ) ) {
 207                         global $wgExtensionAssetsPath;
 208                         $this->remoteBasePath = $wgExtensionAssetsPath . '/' . $options['remoteExtPath'];
 209                 }
 210
 211                 foreach ( $options as $member => $option ) {
 212                         switch ( $member ) {
 213                                 // Lists of file paths
 214                                 case 'scripts':
 215                                 case 'debugScripts':
 216                                 case 'loaderScripts':
 217                                 case 'styles':
 218                                         $this->{$member} = (array)$option;
 219                                         break;
 220                                 // Collated lists of file paths
 221                                 case 'languageScripts':
 222                                 case 'skinScripts':
 223                                 case 'skinStyles':
 224                                         if ( !is_array( $option ) ) {
 225                                                 throw new MWException(
 226                                                         "Invalid collated file path list error. " .
 227                                                         "'$option' given, array expected."
 228                                                 );
 229                                         }
 230                                         foreach ( $option as $key => $value ) {
 231                                                 if ( !is_string( $key ) ) {
 232                                                         throw new MWException(
 233                                                                 "Invalid collated file path list key error. " .
 234                                                                 "'$key' given, string expected."
 235                                                         );
 236                                                 }
 237                                                 $this->{$member}[$key] = (array)$value;
 238                                         }
 239                                         break;
 240                                 // Lists of strings
 241                                 case 'dependencies':
 242                                 case 'messages':
 243                                 case 'targets':
 244                                         $this->{$member} = (array)$option;
 245                                         break;
 246                                 // Single strings
 247                                 case 'group':
 248                                 case 'position':
 249                                 case 'localBasePath':
 250                                 case 'remoteBasePath':
 251                                         $this->{$member} = (string)$option;
 252                                         break;
 253                                 // Single booleans
 254                                 case 'debugRaw':
 255                                 case 'raw':
 256                                         $this->{$member} = (bool)$option;
 257                                         break;
 258                         }
 259                 }
 260                 // Make sure the remote base path is a complete valid URL,
 261                 // but possibly protocol-relative to avoid cache pollution
 262                 $this->remoteBasePath = wfExpandUrl( $this->remoteBasePath, PROTO_RELATIVE );
 263         }
 264
 265         /**
 266          * Gets all scripts for a given context concatenated together.
 267          *
 268          * @param ResourceLoaderContext $context Context in which to generate script
 269          * @return string: JavaScript code for $context
 270          */
 271         public function getScript( ResourceLoaderContext $context ) {
 272                 $files = $this->getScriptFiles( $context );
 273                 return $this->readScriptFiles( $files );
 274         }
 275
 276         /**
 277          * @param ResourceLoaderContext $context
 278          * @return array
 279          */
 280         public function getScriptURLsForDebug( ResourceLoaderContext $context ) {
 281                 $urls = array();
 282                 foreach ( $this->getScriptFiles( $context ) as $file ) {
 283                         $urls[] = $this->getRemotePath( $file );
 284                 }
 285                 return $urls;
 286         }
 287
 288         /**
 289          * @return bool
 290          */
 291         public function supportsURLLoading() {
 292                 return $this->debugRaw;
 293         }
 294
 295         /**
 296          * Gets loader script.
 297          *
 298          * @return string: JavaScript code to be added to startup module
 299          */
 300         public function getLoaderScript() {
 301                 if ( count( $this->loaderScripts ) == 0 ) {
 302                         return false;
 303                 }
 304                 return $this->readScriptFiles( $this->loaderScripts );
 305         }
 306
 307         /**
 308          * Gets all styles for a given context concatenated together.
 309          *
 310          * @param ResourceLoaderContext $context Context in which to generate styles
 311          * @return string: CSS code for $context
 312          */
 313         public function getStyles( ResourceLoaderContext $context ) {
 314                 $styles = $this->readStyleFiles(
 315                         $this->getStyleFiles( $context ),
 316                         $this->getFlip( $context )
 317                 );
 318                 // Collect referenced files
 319                 $this->localFileRefs = array_unique( $this->localFileRefs );
 320                 // If the list has been modified since last time we cached it, update the cache
 321                 try {
 322                         if ( $this->localFileRefs !== $this->getFileDependencies( $context->getSkin() ) ) {
 323                                 $dbw = wfGetDB( DB_MASTER );
 324                                 $dbw->replace( 'module_deps',
 325                                         array( array( 'md_module', 'md_skin' ) ), array(
 326                                                 'md_module' => $this->getName(),
 327                                                 'md_skin' => $context->getSkin(),
 328                                                 'md_deps' => FormatJson::encode( $this->localFileRefs ),
 329                                         )
 330                                 );
 331                         }
 332                 } catch ( Exception $e ) {
 333                         wfDebugLog( 'resourceloader', __METHOD__ . ": failed to update DB: $e" );
 334                 }
 335                 return $styles;
 336         }
 337
 338         /**
 339          * @param ResourceLoaderContext $context
 340          * @return array
 341          */
 342         public function getStyleURLsForDebug( ResourceLoaderContext $context ) {
 343                 if ( $this->hasGeneratedStyles ) {
 344                         // Do the default behaviour of returning a url back to load.php
 345                         // but with only=styles.
 346                         return parent::getStyleURLsForDebug( $context );
 347                 }
 348                 // Our module consists entirely of real css files,
 349                 // in debug mode we can load those directly.
 350                 $urls = array();
 351                 foreach ( $this->getStyleFiles( $context ) as $mediaType => $list ) {
 352                         $urls[$mediaType] = array();
 353                         foreach ( $list as $file ) {
 354                                 $urls[$mediaType][] = $this->getRemotePath( $file );
 355                         }
 356                 }
 357                 return $urls;
 358         }
 359
 360         /**
 361          * Gets list of message keys used by this module.
 362          *
 363          * @return array: List of message keys
 364          */
 365         public function getMessages() {
 366                 return $this->messages;
 367         }
 368
 369         /**
 370          * Gets the name of the group this module should be loaded in.
 371          *
 372          * @return string: Group name
 373          */
 374         public function getGroup() {
 375                 return $this->group;
 376         }
 377
 378         /**
 379          * @return string
 380          */
 381         public function getPosition() {
 382                 return $this->position;
 383         }
 384
 385         /**
 386          * Gets list of names of modules this module depends on.
 387          *
 388          * @return array: List of module names
 389          */
 390         public function getDependencies() {
 391                 return $this->dependencies;
 392         }
 393
 394         /**
 395          * @return bool
 396          */
 397         public function isRaw() {
 398                 return $this->raw;
 399         }
 400
 401         /**
 402          * Get the last modified timestamp of this module.
 403          *
 404          * Last modified timestamps are calculated from the highest last modified
 405          * timestamp of this module's constituent files as well as the files it
 406          * depends on. This function is context-sensitive, only performing
 407          * calculations on files relevant to the given language, skin and debug
 408          * mode.
 409          *
 410          * @param ResourceLoaderContext $context Context in which to calculate
 411          *     the modified time
 412          * @return int: UNIX timestamp
 413          * @see ResourceLoaderModule::getFileDependencies
 414          */
 415         public function getModifiedTime( ResourceLoaderContext $context ) {
 416                 if ( isset( $this->modifiedTime[$context->getHash()] ) ) {
 417                         return $this->modifiedTime[$context->getHash()];
 418                 }
 419                 wfProfileIn( __METHOD__ );
 420
 421                 $files = array();
 422
 423                 // Flatten style files into $files
 424                 $styles = self::collateFilePathListByOption( $this->styles, 'media', 'all' );
 425                 foreach ( $styles as $styleFiles ) {
 426                         $files = array_merge( $files, $styleFiles );
 427                 }
 428                 $skinFiles = self::tryForKey(
 429                         self::collateFilePathListByOption( $this->skinStyles, 'media', 'all' ),
 430                         $context->getSkin(),
 431                         'default'
 432                 );
 433                 foreach ( $skinFiles as $styleFiles ) {
 434                         $files = array_merge( $files, $styleFiles );
 435                 }
 436
 437                 // Final merge, this should result in a master list of dependent files
 438                 $files = array_merge(
 439                         $files,
 440                         $this->scripts,
 441                         $context->getDebug() ? $this->debugScripts : array(),
 442                         self::tryForKey( $this->languageScripts, $context->getLanguage() ),
 443                         self::tryForKey( $this->skinScripts, $context->getSkin(), 'default' ),
 444                         $this->loaderScripts
 445                 );
 446                 $files = array_map( array( $this, 'getLocalPath' ), $files );
 447                 // File deps need to be treated separately because they're already prefixed
 448                 $files = array_merge( $files, $this->getFileDependencies( $context->getSkin() ) );
 449
 450                 // If a module is nothing but a list of dependencies, we need to avoid
 451                 // giving max() an empty array
 452                 if ( count( $files ) === 0 ) {
 453                         wfProfileOut( __METHOD__ );
 454                         return $this->modifiedTime[$context->getHash()] = 1;
 455                 }
 456
 457                 wfProfileIn( __METHOD__ . '-filemtime' );
 458                 $filesMtime = max( array_map( array( __CLASS__, 'safeFilemtime' ), $files ) );
 459                 wfProfileOut( __METHOD__ . '-filemtime' );
 460                 $this->modifiedTime[$context->getHash()] = max(
 461                         $filesMtime,
 462                         $this->getMsgBlobMtime( $context->getLanguage() ) );
 463
 464                 wfProfileOut( __METHOD__ );
 465                 return $this->modifiedTime[$context->getHash()];
 466         }
 467
 468         /* Protected Methods */
 469
 470         /**
 471          * @param string $path
 472          * @return string
 473          */
 474         protected function getLocalPath( $path ) {
 475                 return "{$this->localBasePath}/$path";
 476         }
 477
 478         /**
 479          * @param string $path
 480          * @return string
 481          */
 482         protected function getRemotePath( $path ) {
 483                 return "{$this->remoteBasePath}/$path";
 484         }
 485
 486         /**
 487          * Infer the stylesheet language from a stylesheet file path.
 488          *
 489          * @since 1.22
 490          * @param string $path
 491          * @return string: the stylesheet language name
 492          */
 493         public function getStyleSheetLang( $path ) {
 494                 return preg_match( '/\.less$/i', $path ) ? 'less' : 'css';
 495         }
 496
 497         /**
 498          * Collates file paths by option (where provided).
 499          *
 500          * @param array $list List of file paths in any combination of index/path
 501          *     or path/options pairs
 502          * @param string $option option name
 503          * @param mixed $default default value if the option isn't set
 504          * @return array: List of file paths, collated by $option
 505          */
 506         protected static function collateFilePathListByOption( array $list, $option, $default ) {
 507                 $collatedFiles = array();
 508                 foreach ( (array)$list as $key => $value ) {
 509                         if ( is_int( $key ) ) {
 510                                 // File name as the value
 511                                 if ( !isset( $collatedFiles[$default] ) ) {
 512                                         $collatedFiles[$default] = array();
 513                                 }
 514                                 $collatedFiles[$default][] = $value;
 515                         } elseif ( is_array( $value ) ) {
 516                                 // File name as the key, options array as the value
 517                                 $optionValue = isset( $value[$option] ) ? $value[$option] : $default;
 518                                 if ( !isset( $collatedFiles[$optionValue] ) ) {
 519                                         $collatedFiles[$optionValue] = array();
 520                                 }
 521                                 $collatedFiles[$optionValue][] = $key;
 522                         }
 523                 }
 524                 return $collatedFiles;
 525         }
 526
 527         /**
 528          * Gets a list of element that match a key, optionally using a fallback key.
 529          *
 530          * @param array $list List of lists to select from
 531          * @param string $key Key to look for in $map
 532          * @param string $fallback Key to look for in $list if $key doesn't exist
 533          * @return array: List of elements from $map which matched $key or $fallback,
 534          *     or an empty list in case of no match
 535          */
 536         protected static function tryForKey( array $list, $key, $fallback = null ) {
 537                 if ( isset( $list[$key] ) && is_array( $list[$key] ) ) {
 538                         return $list[$key];
 539                 } elseif ( is_string( $fallback )
 540                         && isset( $list[$fallback] )
 541                         && is_array( $list[$fallback] ) )
 542                 {
 543                         return $list[$fallback];
 544                 }
 545                 return array();
 546         }
 547
 548         /**
 549          * Gets a list of file paths for all scripts in this module, in order of propper execution.
 550          *
 551          * @param ResourceLoaderContext $context
 552          * @return array: List of file paths
 553          */
 554         protected function getScriptFiles( ResourceLoaderContext $context ) {
 555                 $files = array_merge(
 556                         $this->scripts,
 557                         self::tryForKey( $this->languageScripts, $context->getLanguage() ),
 558                         self::tryForKey( $this->skinScripts, $context->getSkin(), 'default' )
 559                 );
 560                 if ( $context->getDebug() ) {
 561                         $files = array_merge( $files, $this->debugScripts );
 562                 }
 563
 564                 return array_unique( $files );
 565         }
 566
 567         /**
 568          * Gets a list of file paths for all styles in this module, in order of propper inclusion.
 569          *
 570          * @param ResourceLoaderContext $context
 571          * @return array: List of file paths
 572          */
 573         protected function getStyleFiles( ResourceLoaderContext $context ) {
 574                 return array_merge_recursive(
 575                         self::collateFilePathListByOption( $this->styles, 'media', 'all' ),
 576                         self::collateFilePathListByOption(
 577                                 self::tryForKey( $this->skinStyles, $context->getSkin(), 'default' ), 'media', 'all'
 578                         )
 579                 );
 580         }
 581
 582         /**
 583          * Returns all style files used by this module
 584          * @return array
 585          */
 586         public function getAllStyleFiles() {
 587                 $files = array();
 588                 foreach ( (array)$this->styles as $key => $value ) {
 589                         if ( is_array( $value ) ) {
 590                                 $path = $key;
 591                         } else {
 592                                 $path = $value;
 593                         }
 594                         $files[] = $this->getLocalPath( $path );
 595                 }
 596                 return $files;
 597         }
 598
 599         /**
 600          * Gets the contents of a list of JavaScript files.
 601          *
 602          * @param array $scripts List of file paths to scripts to read, remap and concetenate
 603          * @throws MWException
 604          * @return string: Concatenated and remapped JavaScript data from $scripts
 605          */
 606         protected function readScriptFiles( array $scripts ) {
 607                 global $wgResourceLoaderValidateStaticJS;
 608                 if ( empty( $scripts ) ) {
 609                         return '';
 610                 }
 611                 $js = '';
 612                 foreach ( array_unique( $scripts ) as $fileName ) {
 613                         $localPath = $this->getLocalPath( $fileName );
 614                         if ( !file_exists( $localPath ) ) {
 615                                 throw new MWException( __METHOD__ . ": script file not found: \"$localPath\"" );
 616                         }
 617                         $contents = file_get_contents( $localPath );
 618                         if ( $wgResourceLoaderValidateStaticJS ) {
 619                                 // Static files don't really need to be checked as often; unlike
 620                                 // on-wiki module they shouldn't change unexpectedly without
 621                                 // admin interference.
 622                                 $contents = $this->validateScriptFile( $fileName, $contents );
 623                         }
 624                         $js .= $contents . "\n";
 625                 }
 626                 return $js;
 627         }
 628
 629         /**
 630          * Gets the contents of a list of CSS files.
 631          *
 632          * @param array $styles List of media type/list of file paths pairs, to read, remap and
 633          * concetenate
 634          *
 635          * @param bool $flip
 636          *
 637          * @return array: List of concatenated and remapped CSS data from $styles,
 638          *     keyed by media type
 639          */
 640         protected function readStyleFiles( array $styles, $flip ) {
 641                 if ( empty( $styles ) ) {
 642                         return array();
 643                 }
 644                 foreach ( $styles as $media => $files ) {
 645                         $uniqueFiles = array_unique( $files );
 646                         $styles[$media] = implode(
 647                                 "\n",
 648                                 array_map(
 649                                         array( $this, 'readStyleFile' ),
 650                                         $uniqueFiles,
 651                                         array_fill( 0, count( $uniqueFiles ), $flip )
 652                                 )
 653                         );
 654                 }
 655                 return $styles;
 656         }
 657
 658         /**
 659          * Reads a style file.
 660          *
 661          * This method can be used as a callback for array_map()
 662          *
 663          * @param string $path File path of style file to read
 664          * @param bool $flip
 665          *
 666          * @return string: CSS data in script file
 667          * @throws MWException if the file doesn't exist
 668          */
 669         protected function readStyleFile( $path, $flip ) {
 670                 $localPath = $this->getLocalPath( $path );
 671                 if ( !file_exists( $localPath ) ) {
 672                         $msg = __METHOD__ . ": style file not found: \"$localPath\"";
 673                         wfDebugLog( 'resourceloader', $msg );
 674                         throw new MWException( $msg );
 675                 }
 676
 677                 if ( $this->getStyleSheetLang( $path ) === 'less' ) {
 678                         $style = $this->compileLESSFile( $localPath );
 679                         $this->hasGeneratedStyles = true;
 680                 } else {
 681                         $style = file_get_contents( $localPath );
 682                 }
 683
 684                 if ( $flip ) {
 685                         $style = CSSJanus::transform( $style, true, false );
 686                 }
 687                 $dirname = dirname( $path );
 688                 if ( $dirname == '.' ) {
 689                         // If $path doesn't have a directory component, don't prepend a dot
 690                         $dirname = '';
 691                 }
 692                 $dir = $this->getLocalPath( $dirname );
 693                 $remoteDir = $this->getRemotePath( $dirname );
 694                 // Get and register local file references
 695                 $this->localFileRefs = array_merge(
 696                         $this->localFileRefs,
 697                         CSSMin::getLocalFileReferences( $style, $dir )
 698                 );
 699                 return CSSMin::remap(
 700                         $style, $dir, $remoteDir, true
 701                 );
 702         }
 703
 704         /**
 705          * Get whether CSS for this module should be flipped
 706          * @param ResourceLoaderContext $context
 707          * @return bool
 708          */
 709         public function getFlip( $context ) {
 710                 return $context->getDirection() === 'rtl';
 711         }
 712
 713         /**
 714          * Get target(s) for the module, eg ['desktop'] or ['desktop', 'mobile']
 715          *
 716          * @return array of strings
 717          */
 718         public function getTargets() {
 719                 return $this->targets;
 720         }
 721
 722         /**
 723          * Generate a cache key for a LESS file.
 724          *
 725          * The cache key varies on the file name and the names and values of global
 726          * LESS variables.
 727          *
 728          * @since 1.22
 729          * @param string $fileName File name of root LESS file.
 730          * @return string: Cache key
 731          */
 732         protected static function getLESSCacheKey( $fileName ) {
 733                 $vars = json_encode( ResourceLoader::getLESSVars() );
 734                 $hash = md5( $fileName . $vars );
 735                 return wfMemcKey( 'resourceloader', 'less', $hash );
 736         }
 737
 738         /**
 739          * Compile a LESS file into CSS.
 740          *
 741          * If invalid, returns replacement CSS source consisting of the compilation
 742          * error message encoded as a comment. To save work, we cache a result object
 743          * which comprises the compiled CSS and the names & mtimes of the files
 744          * that were processed. lessphp compares the cached & current mtimes and
 745          * recompiles as necessary.
 746          *
 747          * @since 1.22
 748          * @throws Exception If Less encounters a parse error
 749          * @throws MWException If Less compilation returns unexpection result
 750          * @param string $fileName File path of LESS source
 751          * @return string: CSS source
 752          */
 753         protected function compileLESSFile( $fileName ) {
 754                 $key = self::getLESSCacheKey( $fileName );
 755                 $cache = wfGetCache( CACHE_ANYTHING );
 756
 757                 // The input to lessc. Either an associative array representing the
 758                 // cached results of a previous compilation, or the string file name if
 759                 // no cache result exists.
 760                 $source = $cache->get( $key );
 761                 if ( !is_array( $source ) || !isset( $source['root'] ) ) {
 762                         $source = $fileName;
 763                 }
 764
 765                 $compiler = ResourceLoader::getLessCompiler();
 766                 $result = null;
 767
 768                 $result = $compiler->cachedCompile( $source );
 769
 770                 if ( !is_array( $result ) ) {
 771                         throw new MWException( 'LESS compiler result has type ' . gettype( $result ) . '; array expected.' );
 772                 }
 773
 774                 $this->localFileRefs += array_keys( $result['files'] );
 775                 $cache->set( $key, $result );
 776                 return $result['compiled'];
 777         }
 778 }