includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @author Roan Kattouw
  20  * @author Trevor Parscal
  21  */
  22
  23 /**
  24  * Dynamic JavaScript and CSS resource loading system.
  25  *
  26  * Most of the documention is on the MediaWiki documentation wiki starting at:
  27  *    http://www.mediawiki.org/wiki/ResourceLoader
  28  */
  29 class ResourceLoader {
  30
  31         /* Protected Static Members */
  32         protected static $filterCacheVersion = 5;
  33         protected static $requiredSourceProperties = array( 'loadScript' );
  34
  35         /** Array: List of module name/ResourceLoaderModule object pairs */
  36         protected $modules = array();
  37
  38         /** Associative array mapping module name to info associative array */
  39         protected $moduleInfos = array();
  40
  41         /** array( 'source-id' => array( 'loadScript' => 'http://.../load.php' ) ) **/
  42         protected $sources = array();
  43
  44         /* Protected Methods */
  45
  46         /**
  47          * Loads information stored in the database about modules.
  48          *
  49          * This method grabs modules dependencies from the database and updates modules
  50          * objects.
  51          *
  52          * This is not inside the module code because it is much faster to
  53          * request all of the information at once than it is to have each module
  54          * requests its own information. This sacrifice of modularity yields a substantial
  55          * performance improvement.
  56          *
  57          * @param $modules Array: List of module names to preload information for
  58          * @param $context ResourceLoaderContext: Context to load the information within
  59          */
  60         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  61                 if ( !count( $modules ) ) {
  62                         return; // or else Database*::select() will explode, plus it's cheaper!
  63                 }
  64                 $dbr = wfGetDB( DB_SLAVE );
  65                 $skin = $context->getSkin();
  66                 $lang = $context->getLanguage();
  67
  68                 // Get file dependency information
  69                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  70                                 'md_module' => $modules,
  71                                 'md_skin' => $skin
  72                         ), __METHOD__
  73                 );
  74
  75                 // Set modules' dependencies
  76                 $modulesWithDeps = array();
  77                 foreach ( $res as $row ) {
  78                         $this->getModule( $row->md_module )->setFileDependencies( $skin,
  79                                 FormatJson::decode( $row->md_deps, true )
  80                         );
  81                         $modulesWithDeps[] = $row->md_module;
  82                 }
  83
  84                 // Register the absence of a dependency row too
  85                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
  86                         $this->getModule( $name )->setFileDependencies( $skin, array() );
  87                 }
  88
  89                 // Get message blob mtimes. Only do this for modules with messages
  90                 $modulesWithMessages = array();
  91                 foreach ( $modules as $name ) {
  92                         if ( count( $this->getModule( $name )->getMessages() ) ) {
  93                                 $modulesWithMessages[] = $name;
  94                         }
  95                 }
  96                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
  97                 if ( count( $modulesWithMessages ) ) {
  98                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
  99                                         'mr_resource' => $modulesWithMessages,
 100                                         'mr_lang' => $lang
 101                                 ), __METHOD__
 102                         );
 103                         foreach ( $res as $row ) {
 104                                 $this->getModule( $row->mr_resource )->setMsgBlobMtime( $lang,
 105                                         wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 106                                 unset( $modulesWithoutMessages[$row->mr_resource] );
 107                         }
 108                 }
 109                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 110                         $this->getModule( $name )->setMsgBlobMtime( $lang, 0 );
 111                 }
 112         }
 113
 114         /**
 115          * Runs JavaScript or CSS data through a filter, caching the filtered result for future calls.
 116          *
 117          * Available filters are:
 118          *  - minify-js \see JavaScriptMinifier::minify
 119          *  - minify-css \see CSSMin::minify
 120          *
 121          * If $data is empty, only contains whitespace or the filter was unknown,
 122          * $data is returned unmodified.
 123          *
 124          * @param $filter String: Name of filter to run
 125          * @param $data String: Text to filter, such as JavaScript or CSS text
 126          * @return String: Filtered data, or a comment containing an error message
 127          */
 128         protected function filter( $filter, $data ) {
 129                 global $wgResourceLoaderMinifierStatementsOnOwnLine, $wgResourceLoaderMinifierMaxLineLength;
 130                 wfProfileIn( __METHOD__ );
 131
 132                 // For empty/whitespace-only data or for unknown filters, don't perform
 133                 // any caching or processing
 134                 if ( trim( $data ) === ''
 135                         || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) )
 136                 {
 137                         wfProfileOut( __METHOD__ );
 138                         return $data;
 139                 }
 140
 141                 // Try for cache hit
 142                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 143                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 144                 $cache = wfGetCache( CACHE_ANYTHING );
 145                 $cacheEntry = $cache->get( $key );
 146                 if ( is_string( $cacheEntry ) ) {
 147                         wfProfileOut( __METHOD__ );
 148                         return $cacheEntry;
 149                 }
 150
 151                 $result = '';
 152                 // Run the filter - we've already verified one of these will work
 153                 try {
 154                         switch ( $filter ) {
 155                                 case 'minify-js':
 156                                         $result = JavaScriptMinifier::minify( $data,
 157                                                 $wgResourceLoaderMinifierStatementsOnOwnLine,
 158                                                 $wgResourceLoaderMinifierMaxLineLength
 159                                         );
 160                                         $result .= "\n\n/* cache key: $key */\n";
 161                                         break;
 162                                 case 'minify-css':
 163                                         $result = CSSMin::minify( $data );
 164                                         $result .= "\n\n/* cache key: $key */\n";
 165                                         break;
 166                         }
 167
 168                         // Save filtered text to Memcached
 169                         $cache->set( $key, $result );
 170                 } catch ( Exception $exception ) {
 171                         // Return exception as a comment
 172                         $result = "/*\n{$exception->__toString()}\n*/\n";
 173                 }
 174
 175                 wfProfileOut( __METHOD__ );
 176
 177                 return $result;
 178         }
 179
 180         /* Methods */
 181
 182         /**
 183          * Registers core modules and runs registration hooks.
 184          */
 185         public function __construct() {
 186                 global $IP, $wgResourceModules, $wgResourceLoaderSources, $wgLoadScript;
 187
 188                 wfProfileIn( __METHOD__ );
 189
 190                 // Add 'local' source first
 191                 $this->addSource( 'local', array( 'loadScript' => $wgLoadScript, 'apiScript' => wfScript( 'api' ) ) );
 192
 193                 // Add other sources
 194                 $this->addSource( $wgResourceLoaderSources );
 195
 196                 // Register core modules
 197                 $this->register( include( "$IP/resources/Resources.php" ) );
 198                 // Register extension modules
 199                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 200                 $this->register( $wgResourceModules );
 201
 202                 wfProfileOut( __METHOD__ );
 203         }
 204
 205         /**
 206          * Registers a module with the ResourceLoader system.
 207          *
 208          * @param $name Mixed: Name of module as a string or List of name/object pairs as an array
 209          * @param $info Module info array. For backwards compatibility with 1.17alpha,
 210          *   this may also be a ResourceLoaderModule object. Optional when using
 211          *   multiple-registration calling style.
 212          * @throws MWException: If a duplicate module registration is attempted
 213          * @throws MWException: If a module name contains illegal characters (pipes or commas)
 214          * @throws MWException: If something other than a ResourceLoaderModule is being registered
 215          * @return Boolean: False if there were any errors, in which case one or more modules were not
 216          *     registered
 217          */
 218         public function register( $name, $info = null ) {
 219                 wfProfileIn( __METHOD__ );
 220
 221                 // Allow multiple modules to be registered in one call
 222                 if ( is_array( $name ) ) {
 223                         foreach ( $name as $key => $value ) {
 224                                 $this->register( $key, $value );
 225                         }
 226                         wfProfileOut( __METHOD__ );
 227                         return;
 228                 }
 229
 230                 // Disallow duplicate registrations
 231                 if ( isset( $this->moduleInfos[$name] ) ) {
 232                         // A module has already been registered by this name
 233                         throw new MWException(
 234                                 'ResourceLoader duplicate registration error. ' .
 235                                 'Another module has already been registered as ' . $name
 236                         );
 237                 }
 238
 239                 // Check $name for illegal characters
 240                 if ( preg_match( '/[|,!]/', $name ) ) {
 241                         throw new MWException( "ResourceLoader module name '$name' is invalid. Names may not contain pipes (|), commas (,) or exclamation marks (!)" );
 242                 }
 243
 244                 // Attach module
 245                 if ( is_object( $info ) ) {
 246                         // Old calling convention
 247                         // Validate the input
 248                         if ( !( $info instanceof ResourceLoaderModule ) ) {
 249                                 throw new MWException( 'ResourceLoader invalid module error. ' .
 250                                         'Instances of ResourceLoaderModule expected.' );
 251                         }
 252
 253                         $this->moduleInfos[$name] = array( 'object' => $info );
 254                         $info->setName( $name );
 255                         $this->modules[$name] = $info;
 256                 } else {
 257                         // New calling convention
 258                         $this->moduleInfos[$name] = $info;
 259                 }
 260
 261                 wfProfileOut( __METHOD__ );
 262         }
 263
 264         /**
 265          * Add a foreign source of modules.
 266          *
 267          * Source properties:
 268          * 'loadScript': URL (either fully-qualified or protocol-relative) of load.php for this source
 269          *
 270          * @param $id Mixed: source ID (string), or array( id1 => props1, id2 => props2, ... )
 271          * @param $properties Array: source properties
 272          */
 273         public function addSource( $id, $properties = null) {
 274                 // Allow multiple sources to be registered in one call
 275                 if ( is_array( $id ) ) {
 276                         foreach ( $id as $key => $value ) {
 277                                 $this->addSource( $key, $value );
 278                         }
 279                         return;
 280                 }
 281
 282                 // Disallow duplicates
 283                 if ( isset( $this->sources[$id] ) ) {
 284                         throw new MWException(
 285                                 'ResourceLoader duplicate source addition error. ' .
 286                                 'Another source has already been registered as ' . $id
 287                         );
 288                 }
 289
 290                 // Validate properties
 291                 foreach ( self::$requiredSourceProperties as $prop ) {
 292                         if ( !isset( $properties[$prop] ) ) {
 293                                 throw new MWException( "Required property $prop missing from source ID $id" );
 294                         }
 295                 }
 296
 297                 $this->sources[$id] = $properties;
 298         }
 299
 300         /**
 301          * Get a list of module names
 302          *
 303          * @return Array: List of module names
 304          */
 305         public function getModuleNames() {
 306                 return array_keys( $this->moduleInfos );
 307         }
 308
 309         /**
 310          * Get the ResourceLoaderModule object for a given module name.
 311          *
 312          * @param $name String: Module name
 313          * @return ResourceLoaderModule if module has been registered, null otherwise
 314          */
 315         public function getModule( $name ) {
 316                 if ( !isset( $this->modules[$name] ) ) {
 317                         if ( !isset( $this->moduleInfos[$name] ) ) {
 318                                 // No such module
 319                                 return null;
 320                         }
 321                         // Construct the requested object
 322                         $info = $this->moduleInfos[$name];
 323                         if ( isset( $info['object'] ) ) {
 324                                 // Object given in info array
 325                                 $object = $info['object'];
 326                         } else {
 327                                 if ( !isset( $info['class'] ) ) {
 328                                         $class = 'ResourceLoaderFileModule';
 329                                 } else {
 330                                         $class = $info['class'];
 331                                 }
 332                                 $object = new $class( $info );
 333                         }
 334                         $object->setName( $name );
 335                         $this->modules[$name] = $object;
 336                 }
 337
 338                 return $this->modules[$name];
 339         }
 340
 341         /**
 342          * Get the list of sources
 343          *
 344          * @return Array: array( id => array of properties, .. )
 345          */
 346         public function getSources() {
 347                 return $this->sources;
 348         }
 349
 350         /**
 351          * Outputs a response to a resource load-request, including a content-type header.
 352          *
 353          * @param $context ResourceLoaderContext: Context in which a response should be formed
 354          */
 355         public function respond( ResourceLoaderContext $context ) {
 356                 global $wgCacheEpoch;
 357
 358                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 359                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 360                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 361                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 362                 // the whole thing in our own output buffer to be sure the active buffer
 363                 // doesn't use ob_gzhandler.
 364                 // See http://bugs.php.net/bug.php?id=36514
 365                 ob_start();
 366
 367                 wfProfileIn( __METHOD__ );
 368                 $exceptions = '';
 369
 370                 // Split requested modules into two groups, modules and missing
 371                 $modules = array();
 372                 $missing = array();
 373                 foreach ( $context->getModules() as $name ) {
 374                         if ( isset( $this->moduleInfos[$name] ) ) {
 375                                 $modules[$name] = $this->getModule( $name );
 376                         } else {
 377                                 $missing[] = $name;
 378                         }
 379                 }
 380
 381                 // Preload information needed to the mtime calculation below
 382                 try {
 383                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 384                 } catch( Exception $e ) {
 385                         // Add exception to the output as a comment
 386                         $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 387                 }
 388
 389                 wfProfileIn( __METHOD__.'-getModifiedTime' );
 390
 391                 $private = false;
 392                 // To send Last-Modified and support If-Modified-Since, we need to detect
 393                 // the last modified time
 394                 $mtime = wfTimestamp( TS_UNIX, $wgCacheEpoch );
 395                 foreach ( $modules as $module ) {
 396                         try {
 397                                 // Bypass Squid and other shared caches if the request includes any private modules
 398                                 if ( $module->getGroup() === 'private' ) {
 399                                         $private = true;
 400                                 }
 401                                 // Calculate maximum modified time
 402                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 403                         } catch ( Exception $e ) {
 404                                 // Add exception to the output as a comment
 405                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 406                         }
 407                 }
 408
 409                 wfProfileOut( __METHOD__.'-getModifiedTime' );
 410
 411                 // Send content type and cache related headers
 412                 $this->sendResponseHeaders( $context, $mtime, $private );
 413
 414                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 415                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 416                         return; // output handled (buffers cleared)
 417                 }
 418
 419                 // Generate a response
 420                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 421
 422                 // Prepend comments indicating exceptions
 423                 $response = $exceptions . $response;
 424
 425                 // Capture any PHP warnings from the output buffer and append them to the
 426                 // response in a comment if we're in debug mode.
 427                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 428                         $response = "/*\n$warnings\n*/\n" . $response;
 429                 }
 430
 431                 // Remove the output buffer and output the response
 432                 ob_end_clean();
 433                 echo $response;
 434
 435                 wfProfileOut( __METHOD__ );
 436         }
 437
 438         /**
 439          * Send content type and last modified headers to the client.
 440          * @param $context ResourceLoaderContext
 441          * @param $mtime string TS_MW timestamp to use for last-modified
 442          * @param $private bool True iff response contains any private modules
 443          * @return void
 444          */
 445         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $private ) {
 446                 global $wgResourceLoaderMaxage;
 447                 // If a version wasn't specified we need a shorter expiry time for updates
 448                 // to propagate to clients quickly
 449                 if ( is_null( $context->getVersion() ) ) {
 450                         $maxage  = $wgResourceLoaderMaxage['unversioned']['client'];
 451                         $smaxage = $wgResourceLoaderMaxage['unversioned']['server'];
 452                 // If a version was specified we can use a longer expiry time since changing
 453                 // version numbers causes cache misses
 454                 } else {
 455                         $maxage  = $wgResourceLoaderMaxage['versioned']['client'];
 456                         $smaxage = $wgResourceLoaderMaxage['versioned']['server'];
 457                 }
 458                 if ( $context->getOnly() === 'styles' ) {
 459                         header( 'Content-Type: text/css; charset=utf-8' );
 460                 } else {
 461                         header( 'Content-Type: text/javascript; charset=utf-8' );
 462                 }
 463                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 464                 if ( $context->getDebug() ) {
 465                         // Do not cache debug responses
 466                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 467                         header( 'Pragma: no-cache' );
 468                 } else {
 469                         if ( $private ) {
 470                                 header( "Cache-Control: private, max-age=$maxage" );
 471                                 $exp = $maxage;
 472                         } else {
 473                                 header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 474                                 $exp = min( $maxage, $smaxage );
 475                         }
 476                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 477                 }
 478         }
 479
 480         /**
 481          * If there's an If-Modified-Since header, respond with a 304 appropriately
 482          * and clear out the output buffer. If the client cache is too old then do nothing.
 483          * @param $context ResourceLoaderContext
 484          * @param $mtime string The TS_MW timestamp to check the header against
 485          * @return bool True iff 304 header sent and output handled
 486          */
 487         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 488                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 489                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 490                 // so we get a valid timestamp.
 491                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 492                 // Never send 304s in debug mode
 493                 if ( $ims !== false && !$context->getDebug() ) {
 494                         $imsTS = strtok( $ims, ';' );
 495                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 496                                 // There's another bug in ob_gzhandler (see also the comment at
 497                                 // the top of this function) that causes it to gzip even empty
 498                                 // responses, meaning it's impossible to produce a truly empty
 499                                 // response (because the gzip header is always there). This is
 500                                 // a problem because 304 responses have to be completely empty
 501                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 502                                 // See also http://bugs.php.net/bug.php?id=51579
 503                                 // To work around this, we tear down all output buffering before
 504                                 // sending the 304.
 505                                 // On some setups, ob_get_level() doesn't seem to go down to zero
 506                                 // no matter how often we call ob_get_clean(), so instead of doing
 507                                 // the more intuitive while ( ob_get_level() > 0 ) ob_get_clean();
 508                                 // we have to be safe here and avoid an infinite loop.
 509                                 for ( $i = 0; $i < ob_get_level(); $i++ ) {
 510                                         ob_end_clean();
 511                                 }
 512
 513                                 header( 'HTTP/1.0 304 Not Modified' );
 514                                 header( 'Status: 304 Not Modified' );
 515                                 wfProfileOut( __METHOD__ );
 516                                 return true;
 517                         }
 518                 }
 519                 return false;
 520         }
 521
 522         /**
 523          * Generates code for a response
 524          *
 525          * @param $context ResourceLoaderContext: Context in which to generate a response
 526          * @param $modules Array: List of module objects keyed by module name
 527          * @param $missing Array: List of unavailable modules (optional)
 528          * @return String: Response data
 529          */
 530         public function makeModuleResponse( ResourceLoaderContext $context,
 531                 array $modules, $missing = array() )
 532         {
 533                 $out = '';
 534                 $exceptions = '';
 535                 if ( $modules === array() && $missing === array() ) {
 536                         return '/* No modules requested. Max made me put this here */';
 537                 }
 538
 539                 wfProfileIn( __METHOD__ );
 540                 // Pre-fetch blobs
 541                 if ( $context->shouldIncludeMessages() ) {
 542                         try {
 543                                 $blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
 544                         } catch ( Exception $e ) {
 545                                 // Add exception to the output as a comment
 546                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 547                         }
 548                 } else {
 549                         $blobs = array();
 550                 }
 551
 552                 // Generate output
 553                 foreach ( $modules as $name => $module ) {
 554                         wfProfileIn( __METHOD__ . '-' . $name );
 555                         try {
 556                                 $scripts = '';
 557                                 if ( $context->shouldIncludeScripts() ) {
 558                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 559                                         // However, we can't do this if the module doesn't support it
 560                                         // We also can't do this if there is an only= parameter, because we have to give
 561                                         // the module a way to return a load.php URL without causing an infinite loop
 562                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 563                                                 $scripts = $module->getScriptURLsForDebug( $context );
 564                                         } else {
 565                                                 $scripts = $module->getScript( $context );
 566                                                 if ( is_string( $scripts ) ) {
 567                                                         // bug 27054: Append semicolon to prevent weird bugs
 568                                                         // caused by files not terminating their statements right
 569                                                         $scripts .= ";\n";
 570                                                 }
 571                                         }
 572                                 }
 573                                 // Styles
 574                                 $styles = array();
 575                                 if ( $context->shouldIncludeStyles() ) {
 576                                         // If we are in debug mode, we'll want to return an array of URLs
 577                                         // See comment near shouldIncludeScripts() for more details
 578                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 579                                                 $styles = $module->getStyleURLsForDebug( $context );
 580                                         } else {
 581                                                 $styles = $module->getStyles( $context );
 582                                         }
 583                                 }
 584
 585                                 // Messages
 586                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 587
 588                                 // Append output
 589                                 switch ( $context->getOnly() ) {
 590                                         case 'scripts':
 591                                                 if ( is_string( $scripts ) ) {
 592                                                         // Load scripts raw...
 593                                                         $out .= $scripts;
 594                                                 } elseif ( is_array( $scripts ) ) {
 595                                                         // ...except when $scripts is an array of URLs
 596                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 597                                                 }
 598                                                 break;
 599                                         case 'styles':
 600                                                 $out .= self::makeCombinedStyles( $styles );
 601                                                 break;
 602                                         case 'messages':
 603                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 604                                                 break;
 605                                         default:
 606                                                 // Minify CSS before embedding in mw.loader.implement call
 607                                                 // (unless in debug mode)
 608                                                 if ( !$context->getDebug() ) {
 609                                                         foreach ( $styles as $media => $style ) {
 610                                                                 if ( is_string( $style ) ) {
 611                                                                         $styles[$media] = $this->filter( 'minify-css', $style );
 612                                                                 }
 613                                                         }
 614                                                 }
 615                                                 $out .= self::makeLoaderImplementScript( $name, $scripts, $styles,
 616                                                         new XmlJsCode( $messagesBlob ) );
 617                                                 break;
 618                                 }
 619                         } catch ( Exception $e ) {
 620                                 // Add exception to the output as a comment
 621                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 622
 623                                 // Register module as missing
 624                                 $missing[] = $name;
 625                                 unset( $modules[$name] );
 626                         }
 627                         wfProfileOut( __METHOD__ . '-' . $name );
 628                 }
 629
 630                 // Update module states
 631                 if ( $context->shouldIncludeScripts() ) {
 632                         // Set the state of modules loaded as only scripts to ready
 633                         if ( count( $modules ) && $context->getOnly() === 'scripts'
 634                                 && !isset( $modules['startup'] ) )
 635                         {
 636                                 $out .= self::makeLoaderStateScript(
 637                                         array_fill_keys( array_keys( $modules ), 'ready' ) );
 638                         }
 639                         // Set the state of modules which were requested but unavailable as missing
 640                         if ( is_array( $missing ) && count( $missing ) ) {
 641                                 $out .= self::makeLoaderStateScript( array_fill_keys( $missing, 'missing' ) );
 642                         }
 643                 }
 644
 645                 if ( !$context->getDebug() ) {
 646                         if ( $context->getOnly() === 'styles' ) {
 647                                 $out = $this->filter( 'minify-css', $out );
 648                         } else {
 649                                 $out = $this->filter( 'minify-js', $out );
 650                         }
 651                 }
 652
 653                 wfProfileOut( __METHOD__ );
 654                 return $exceptions . $out;
 655         }
 656
 657         /* Static Methods */
 658
 659         /**
 660          * Returns JS code to call to mw.loader.implement for a module with
 661          * given properties.
 662          *
 663          * @param $name Module name
 664          * @param $scripts Mixed: List of URLs to JavaScript files or String of JavaScript code
 665          * @param $styles Mixed: List of CSS strings keyed by media type, or list of lists of URLs to
 666          * CSS files keyed by media type
 667          * @param $messages Mixed: List of messages associated with this module. May either be an
 668          *     associative array mapping message key to value, or a JSON-encoded message blob containing
 669          *     the same data, wrapped in an XmlJsCode object.
 670          *
 671          * @return string
 672          */
 673         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
 674                 if ( is_string( $scripts ) ) {
 675                         $scripts = new XmlJsCode( "function( $ ) {{$scripts}}" );
 676                 } elseif ( !is_array( $scripts ) ) {
 677                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
 678                 }
 679                 return Xml::encodeJsCall(
 680                         'mw.loader.implement',
 681                         array(
 682                                 $name,
 683                                 $scripts,
 684                                 (object)$styles,
 685                                 (object)$messages
 686                         ) );
 687         }
 688
 689         /**
 690          * Returns JS code which, when called, will register a given list of messages.
 691          *
 692          * @param $messages Mixed: Either an associative array mapping message key to value, or a
 693          *     JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
 694          *
 695          * @return string
 696          */
 697         public static function makeMessageSetScript( $messages ) {
 698                 return Xml::encodeJsCall( 'mw.messages.set', array( (object)$messages ) );
 699         }
 700
 701         /**
 702          * Combines an associative array mapping media type to CSS into a
 703          * single stylesheet with @media blocks.
 704          *
 705          * @param $styles Array: List of CSS strings keyed by media type
 706          *
 707          * @return string
 708          */
 709         public static function makeCombinedStyles( array $styles ) {
 710                 $out = '';
 711                 foreach ( $styles as $media => $style ) {
 712                         // Transform the media type based on request params and config
 713                         // The way that this relies on $wgRequest to propagate request params is slightly evil
 714                         $media = OutputPage::transformCssMedia( $media );
 715
 716                         if ( $media === null ) {
 717                                 // Skip
 718                         } elseif ( $media === '' || $media == 'all' ) {
 719                                 // Don't output invalid or frivolous @media statements
 720                                 $out .= "$style\n";
 721                         } else {
 722                                 $out .= "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "\n}\n";
 723                         }
 724                 }
 725                 return $out;
 726         }
 727
 728         /**
 729          * Returns a JS call to mw.loader.state, which sets the state of a
 730          * module or modules to a given value. Has two calling conventions:
 731          *
 732          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
 733          *         Set the state of a single module called $name to $state
 734          *
 735          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
 736          *         Set the state of modules with the given names to the given states
 737          *
 738          * @param $name string
 739          * @param $state
 740          *
 741          * @return string
 742          */
 743         public static function makeLoaderStateScript( $name, $state = null ) {
 744                 if ( is_array( $name ) ) {
 745                         return Xml::encodeJsCall( 'mw.loader.state', array( $name ) );
 746                 } else {
 747                         return Xml::encodeJsCall( 'mw.loader.state', array( $name, $state ) );
 748                 }
 749         }
 750
 751         /**
 752          * Returns JS code which calls the script given by $script. The script will
 753          * be called with local variables name, version, dependencies and group,
 754          * which will have values corresponding to $name, $version, $dependencies
 755          * and $group as supplied.
 756          *
 757          * @param $name String: Module name
 758          * @param $version Integer: Module version number as a timestamp
 759          * @param $dependencies Array: List of module names on which this module depends
 760          * @param $group String: Group which the module is in.
 761          * @param $source String: Source of the module, or 'local' if not foreign.
 762          * @param $script String: JavaScript code
 763          *
 764          * @return string
 765          */
 766         public static function makeCustomLoaderScript( $name, $version, $dependencies, $group, $source, $script ) {
 767                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 768                 return Xml::encodeJsCall(
 769                         "( function( name, version, dependencies, group, source ) {\n\t$script\n} )",
 770                         array( $name, $version, $dependencies, $group, $source ) );
 771         }
 772
 773         /**
 774          * Returns JS code which calls mw.loader.register with the given
 775          * parameters. Has three calling conventions:
 776          *
 777          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version, $dependencies, $group, $source ):
 778          *       Register a single module.
 779          *
 780          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
 781          *       Register modules with the given names.
 782          *
 783          *   - ResourceLoader::makeLoaderRegisterScript( array(
 784          *        array( $name1, $version1, $dependencies1, $group1, $source1 ),
 785          *        array( $name2, $version2, $dependencies1, $group2, $source2 ),
 786          *        ...
 787          *     ) ):
 788          *        Registers modules with the given names and parameters.
 789          *
 790          * @param $name String: Module name
 791          * @param $version Integer: Module version number as a timestamp
 792          * @param $dependencies Array: List of module names on which this module depends
 793          * @param $group String: group which the module is in.
 794          * @param $source String: source of the module, or 'local' if not foreign
 795          *
 796          * @return string
 797          */
 798         public static function makeLoaderRegisterScript( $name, $version = null,
 799                 $dependencies = null, $group = null, $source = null )
 800         {
 801                 if ( is_array( $name ) ) {
 802                         return Xml::encodeJsCall( 'mw.loader.register', array( $name ) );
 803                 } else {
 804                         $version = (int) $version > 1 ? (int) $version : 1;
 805                         return Xml::encodeJsCall( 'mw.loader.register',
 806                                 array( $name, $version, $dependencies, $group, $source ) );
 807                 }
 808         }
 809
 810         /**
 811          * Returns JS code which calls mw.loader.addSource() with the given
 812          * parameters. Has two calling conventions:
 813          *
 814          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
 815          *       Register a single source
 816          *
 817          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $props1, $id2 => $props2, ... ) );
 818          *       Register sources with the given IDs and properties.
 819          *
 820          * @param $id String: source ID
 821          * @param $properties Array: source properties (see addSource())
 822          *
 823          * @return string
 824          */
 825         public static function makeLoaderSourcesScript( $id, $properties = null ) {
 826                 if ( is_array( $id ) ) {
 827                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id ) );
 828                 } else {
 829                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id, $properties ) );
 830                 }
 831         }
 832
 833         /**
 834          * Returns JS code which runs given JS code if the client-side framework is
 835          * present.
 836          *
 837          * @param $script String: JavaScript code
 838          *
 839          * @return string
 840          */
 841         public static function makeLoaderConditionalScript( $script ) {
 842                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 843                 return "if(window.mw){\n\t$script\n}\n";
 844         }
 845
 846         /**
 847          * Returns JS code which will set the MediaWiki configuration array to
 848          * the given value.
 849          *
 850          * @param $configuration Array: List of configuration values keyed by variable name
 851          *
 852          * @return string
 853          */
 854         public static function makeConfigSetScript( array $configuration ) {
 855                 return Xml::encodeJsCall( 'mw.config.set', array( $configuration ) );
 856         }
 857
 858         /**
 859          * Convert an array of module names to a packed query string.
 860          *
 861          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
 862          * becomes 'foo.bar,baz|bar.baz,quux'
 863          * @param $modules array of module names (strings)
 864          * @return string Packed query string
 865          */
 866         public static function makePackedModulesString( $modules ) {
 867                 $groups = array(); // array( prefix => array( suffixes ) )
 868                 foreach ( $modules as $module ) {
 869                         $pos = strrpos( $module, '.' );
 870                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
 871                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
 872                         $groups[$prefix][] = $suffix;
 873                 }
 874
 875                 $arr = array();
 876                 foreach ( $groups as $prefix => $suffixes ) {
 877                         $p = $prefix === '' ? '' : $prefix . '.';
 878                         $arr[] = $p . implode( ',', $suffixes );
 879                 }
 880                 $str = implode( '|', $arr );
 881                 return $str;
 882         }
 883
 884         /**
 885          * Determine whether debug mode was requested
 886          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
 887          * @return bool
 888          */
 889         public static function inDebugMode() {
 890                 global $wgRequest, $wgResourceLoaderDebug;
 891                 static $retval = null;
 892                 if ( !is_null( $retval ) ) {
 893                         return $retval;
 894                 }
 895                 return $retval = $wgRequest->getFuzzyBool( 'debug',
 896                         $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug ) );
 897         }
 898
 899         /**
 900          * Build a load.php URL
 901          * @param $modules array of module names (strings)
 902          * @param $lang string Language code
 903          * @param $skin string Skin name
 904          * @param $user string|null User name. If null, the &user= parameter is omitted
 905          * @param $version string|null Versioning timestamp
 906          * @param $debug bool Whether the request should be in debug mode
 907          * @param $only string|null &only= parameter
 908          * @param $printable bool Printable mode
 909          * @param $handheld bool Handheld mode
 910          * @param $extraQuery array Extra query parameters to add
 911          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
 912          */
 913         public static function makeLoaderURL( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
 914                         $printable = false, $handheld = false, $extraQuery = array() ) {
 915                 global $wgLoadScript;
 916                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
 917                         $only, $printable, $handheld, $extraQuery
 918                 );
 919
 920                 // Prevent the IE6 extension check from being triggered (bug 28840)
 921                 // by appending a character that's invalid in Windows extensions ('*')
 922                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
 923         }
 924
 925         /**
 926          * Build a query array (array representation of query string) for load.php. Helper
 927          * function for makeLoaderURL().
 928          * @return array
 929          */
 930         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
 931                         $printable = false, $handheld = false, $extraQuery = array() ) {
 932                 $query = array(
 933                         'modules' => self::makePackedModulesString( $modules ),
 934                         'lang' => $lang,
 935                         'skin' => $skin,
 936                         'debug' => $debug ? 'true' : 'false',
 937                 );
 938                 if ( $user !== null ) {
 939                         $query['user'] = $user;
 940                 }
 941                 if ( $version !== null ) {
 942                         $query['version'] = $version;
 943                 }
 944                 if ( $only !== null ) {
 945                         $query['only'] = $only;
 946                 }
 947                 if ( $printable ) {
 948                         $query['printable'] = 1;
 949                 }
 950                 if ( $handheld ) {
 951                         $query['handheld'] = 1;
 952                 }
 953                 $query += $extraQuery;
 954
 955                 // Make queries uniform in order
 956                 ksort( $query );
 957                 return $query;
 958         }
 959 }