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, $wgUseFileCache;
 357
 358                 // Use file cache if enabled and available...
 359                 if ( $wgUseFileCache ) {
 360                         $fileCache = ResourceFileCache::newFromContext( $context );
 361                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 362                                 return; // output handled
 363                         }
 364                 }
 365
 366                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 367                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 368                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 369                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 370                 // the whole thing in our own output buffer to be sure the active buffer
 371                 // doesn't use ob_gzhandler.
 372                 // See http://bugs.php.net/bug.php?id=36514
 373                 ob_start();
 374
 375                 wfProfileIn( __METHOD__ );
 376                 $exceptions = '';
 377
 378                 // Split requested modules into two groups, modules and missing
 379                 $modules = array();
 380                 $missing = array();
 381                 foreach ( $context->getModules() as $name ) {
 382                         if ( isset( $this->moduleInfos[$name] ) ) {
 383                                 $modules[$name] = $this->getModule( $name );
 384                         } else {
 385                                 $missing[] = $name;
 386                         }
 387                 }
 388
 389                 // Preload information needed to the mtime calculation below
 390                 try {
 391                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 392                 } catch( Exception $e ) {
 393                         // Add exception to the output as a comment
 394                         $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 395                 }
 396
 397                 wfProfileIn( __METHOD__.'-getModifiedTime' );
 398
 399                 $private = false;
 400                 // To send Last-Modified and support If-Modified-Since, we need to detect
 401                 // the last modified time
 402                 $mtime = wfTimestamp( TS_UNIX, $wgCacheEpoch );
 403                 foreach ( $modules as $module ) {
 404                         try {
 405                                 // Bypass Squid and other shared caches if the request includes any private modules
 406                                 if ( $module->getGroup() === 'private' ) {
 407                                         $private = true;
 408                                 }
 409                                 // Calculate maximum modified time
 410                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 411                         } catch ( Exception $e ) {
 412                                 // Add exception to the output as a comment
 413                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 414                         }
 415                 }
 416
 417                 wfProfileOut( __METHOD__.'-getModifiedTime' );
 418
 419                 // Send content type and cache related headers
 420                 $this->sendResponseHeaders( $context, $mtime, $private );
 421
 422                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 423                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 424                         return; // output handled (buffers cleared)
 425                 }
 426
 427                 // Generate a response
 428                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 429
 430                 // Prepend comments indicating exceptions
 431                 $response = $exceptions . $response;
 432
 433                 // Capture any PHP warnings from the output buffer and append them to the
 434                 // response in a comment if we're in debug mode.
 435                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 436                         $response = "/*\n$warnings\n*/\n" . $response;
 437                 }
 438
 439                 // Remove the output buffer and output the response
 440                 ob_end_clean();
 441                 echo $response;
 442
 443                 // Save response to file cache unless there are private modules or errors
 444                 if ( isset( $fileCache ) && !$private && !$exceptions && !$missing ) {
 445                         // Cache single modules...and other requests if there are enough hits
 446                         if ( ResourceFileCache::useFileCache( $context ) ) {
 447                                 if ( $fileCache->isCacheWorthy() ) {
 448                                         $fileCache->saveText( $response );
 449                                 } else {
 450                                         $fileCache->incrMissesRecent( $context->getRequest() );
 451                                 }
 452                         }
 453                 }
 454
 455                 wfProfileOut( __METHOD__ );
 456         }
 457
 458         /**
 459          * Send content type and last modified headers to the client.
 460          * @param $context ResourceLoaderContext
 461          * @param $mtime string TS_MW timestamp to use for last-modified
 462          * @param $private bool True iff response contains any private modules
 463          * @return void
 464          */
 465         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $private ) {
 466                 global $wgResourceLoaderMaxage;
 467                 // If a version wasn't specified we need a shorter expiry time for updates
 468                 // to propagate to clients quickly
 469                 if ( is_null( $context->getVersion() ) ) {
 470                         $maxage  = $wgResourceLoaderMaxage['unversioned']['client'];
 471                         $smaxage = $wgResourceLoaderMaxage['unversioned']['server'];
 472                 // If a version was specified we can use a longer expiry time since changing
 473                 // version numbers causes cache misses
 474                 } else {
 475                         $maxage  = $wgResourceLoaderMaxage['versioned']['client'];
 476                         $smaxage = $wgResourceLoaderMaxage['versioned']['server'];
 477                 }
 478                 if ( $context->getOnly() === 'styles' ) {
 479                         header( 'Content-Type: text/css; charset=utf-8' );
 480                 } else {
 481                         header( 'Content-Type: text/javascript; charset=utf-8' );
 482                 }
 483                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 484                 if ( $context->getDebug() ) {
 485                         // Do not cache debug responses
 486                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 487                         header( 'Pragma: no-cache' );
 488                 } else {
 489                         if ( $private ) {
 490                                 header( "Cache-Control: private, max-age=$maxage" );
 491                                 $exp = $maxage;
 492                         } else {
 493                                 header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 494                                 $exp = min( $maxage, $smaxage );
 495                         }
 496                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 497                 }
 498         }
 499
 500         /**
 501          * If there's an If-Modified-Since header, respond with a 304 appropriately
 502          * and clear out the output buffer. If the client cache is too old then do nothing.
 503          * @param $context ResourceLoaderContext
 504          * @param $mtime string The TS_MW timestamp to check the header against
 505          * @return bool True iff 304 header sent and output handled
 506          */
 507         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 508                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 509                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 510                 // so we get a valid timestamp.
 511                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 512                 // Never send 304s in debug mode
 513                 if ( $ims !== false && !$context->getDebug() ) {
 514                         $imsTS = strtok( $ims, ';' );
 515                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 516                                 // There's another bug in ob_gzhandler (see also the comment at
 517                                 // the top of this function) that causes it to gzip even empty
 518                                 // responses, meaning it's impossible to produce a truly empty
 519                                 // response (because the gzip header is always there). This is
 520                                 // a problem because 304 responses have to be completely empty
 521                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 522                                 // See also http://bugs.php.net/bug.php?id=51579
 523                                 // To work around this, we tear down all output buffering before
 524                                 // sending the 304.
 525                                 // On some setups, ob_get_level() doesn't seem to go down to zero
 526                                 // no matter how often we call ob_get_clean(), so instead of doing
 527                                 // the more intuitive while ( ob_get_level() > 0 ) ob_get_clean();
 528                                 // we have to be safe here and avoid an infinite loop.
 529                                 for ( $i = 0; $i < ob_get_level(); $i++ ) {
 530                                         ob_end_clean();
 531                                 }
 532
 533                                 header( 'HTTP/1.0 304 Not Modified' );
 534                                 header( 'Status: 304 Not Modified' );
 535                                 wfProfileOut( __METHOD__ );
 536                                 return true;
 537                         }
 538                 }
 539                 return false;
 540         }
 541
 542         /**
 543          * Send out code for a response from file cache if possible
 544          *
 545          * @param $fileCache ObjectFileCache: Cache object for this request URL
 546          * @param $context ResourceLoaderContext: Context in which to generate a response
 547          * @return bool If this found a cache file and handled the response
 548          */
 549         protected function tryRespondFromFileCache(
 550                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 551         ) {
 552                 global $wgResourceLoaderMaxage;
 553                 // Buffer output to catch warnings.
 554                 ob_start();
 555                 // Get the maximum age the cache can be
 556                 $maxage = is_null( $context->getVersion() )
 557                         ? $wgResourceLoaderMaxage['unversioned']['server']
 558                         : $wgResourceLoaderMaxage['versioned']['server'];
 559                 // Minimum timestamp the cache file must have
 560                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 561                 if ( !$good ) {
 562                         try { // RL always hits the DB on file cache miss...
 563                                 wfGetDB( DB_SLAVE );
 564                         } catch( DBConnectionError $e ) { // ...check if we need to fallback to cache
 565                                 $good = $fileCache->isCacheGood(); // cache existence check
 566                         }
 567                 }
 568                 if ( $good ) {
 569                         $ts = $fileCache->cacheTimestamp();
 570                         // Send content type and cache headers
 571                         $this->sendResponseHeaders( $context, $ts, false );
 572                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 573                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 574                                 return; // output handled (buffers cleared)
 575                         }
 576                         $response = $fileCache->fetchText();
 577                         // Remove the output buffer and output the response
 578                         ob_end_clean();
 579                         echo $response . "\n/* Cached {$ts} */";
 580                         return true; // cache hit
 581                 }
 582                 // Clear buffer
 583                 ob_end_clean();
 584
 585                 return false; // cache miss
 586         }
 587
 588         /**
 589          * Generates code for a response
 590          *
 591          * @param $context ResourceLoaderContext: Context in which to generate a response
 592          * @param $modules Array: List of module objects keyed by module name
 593          * @param $missing Array: List of unavailable modules (optional)
 594          * @return String: Response data
 595          */
 596         public function makeModuleResponse( ResourceLoaderContext $context,
 597                 array $modules, $missing = array() )
 598         {
 599                 $out = '';
 600                 $exceptions = '';
 601                 if ( $modules === array() && $missing === array() ) {
 602                         return '/* No modules requested. Max made me put this here */';
 603                 }
 604
 605                 wfProfileIn( __METHOD__ );
 606                 // Pre-fetch blobs
 607                 if ( $context->shouldIncludeMessages() ) {
 608                         try {
 609                                 $blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
 610                         } catch ( Exception $e ) {
 611                                 // Add exception to the output as a comment
 612                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 613                         }
 614                 } else {
 615                         $blobs = array();
 616                 }
 617
 618                 // Generate output
 619                 foreach ( $modules as $name => $module ) {
 620                         wfProfileIn( __METHOD__ . '-' . $name );
 621                         try {
 622                                 $scripts = '';
 623                                 if ( $context->shouldIncludeScripts() ) {
 624                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 625                                         // However, we can't do this if the module doesn't support it
 626                                         // We also can't do this if there is an only= parameter, because we have to give
 627                                         // the module a way to return a load.php URL without causing an infinite loop
 628                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 629                                                 $scripts = $module->getScriptURLsForDebug( $context );
 630                                         } else {
 631                                                 $scripts = $module->getScript( $context );
 632                                                 if ( is_string( $scripts ) ) {
 633                                                         // bug 27054: Append semicolon to prevent weird bugs
 634                                                         // caused by files not terminating their statements right
 635                                                         $scripts .= ";\n";
 636                                                 }
 637                                         }
 638                                 }
 639                                 // Styles
 640                                 $styles = array();
 641                                 if ( $context->shouldIncludeStyles() ) {
 642                                         // If we are in debug mode, we'll want to return an array of URLs
 643                                         // See comment near shouldIncludeScripts() for more details
 644                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 645                                                 $styles = $module->getStyleURLsForDebug( $context );
 646                                         } else {
 647                                                 $styles = $module->getStyles( $context );
 648                                         }
 649                                 }
 650
 651                                 // Messages
 652                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 653
 654                                 // Append output
 655                                 switch ( $context->getOnly() ) {
 656                                         case 'scripts':
 657                                                 if ( is_string( $scripts ) ) {
 658                                                         // Load scripts raw...
 659                                                         $out .= $scripts;
 660                                                 } elseif ( is_array( $scripts ) ) {
 661                                                         // ...except when $scripts is an array of URLs
 662                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 663                                                 }
 664                                                 break;
 665                                         case 'styles':
 666                                                 $out .= self::makeCombinedStyles( $styles );
 667                                                 break;
 668                                         case 'messages':
 669                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 670                                                 break;
 671                                         default:
 672                                                 // Minify CSS before embedding in mw.loader.implement call
 673                                                 // (unless in debug mode)
 674                                                 if ( !$context->getDebug() ) {
 675                                                         foreach ( $styles as $media => $style ) {
 676                                                                 if ( is_string( $style ) ) {
 677                                                                         $styles[$media] = $this->filter( 'minify-css', $style );
 678                                                                 }
 679                                                         }
 680                                                 }
 681                                                 $out .= self::makeLoaderImplementScript( $name, $scripts, $styles,
 682                                                         new XmlJsCode( $messagesBlob ) );
 683                                                 break;
 684                                 }
 685                         } catch ( Exception $e ) {
 686                                 // Add exception to the output as a comment
 687                                 $exceptions .= "/*\n{$e->__toString()}\n*/\n";
 688
 689                                 // Register module as missing
 690                                 $missing[] = $name;
 691                                 unset( $modules[$name] );
 692                         }
 693                         wfProfileOut( __METHOD__ . '-' . $name );
 694                 }
 695
 696                 // Update module states
 697                 if ( $context->shouldIncludeScripts() ) {
 698                         // Set the state of modules loaded as only scripts to ready
 699                         if ( count( $modules ) && $context->getOnly() === 'scripts'
 700                                 && !isset( $modules['startup'] ) )
 701                         {
 702                                 $out .= self::makeLoaderStateScript(
 703                                         array_fill_keys( array_keys( $modules ), 'ready' ) );
 704                         }
 705                         // Set the state of modules which were requested but unavailable as missing
 706                         if ( is_array( $missing ) && count( $missing ) ) {
 707                                 $out .= self::makeLoaderStateScript( array_fill_keys( $missing, 'missing' ) );
 708                         }
 709                 }
 710
 711                 if ( !$context->getDebug() ) {
 712                         if ( $context->getOnly() === 'styles' ) {
 713                                 $out = $this->filter( 'minify-css', $out );
 714                         } else {
 715                                 $out = $this->filter( 'minify-js', $out );
 716                         }
 717                 }
 718
 719                 wfProfileOut( __METHOD__ );
 720                 return $exceptions . $out;
 721         }
 722
 723         /* Static Methods */
 724
 725         /**
 726          * Returns JS code to call to mw.loader.implement for a module with
 727          * given properties.
 728          *
 729          * @param $name Module name
 730          * @param $scripts Mixed: List of URLs to JavaScript files or String of JavaScript code
 731          * @param $styles Mixed: List of CSS strings keyed by media type, or list of lists of URLs to
 732          * CSS files keyed by media type
 733          * @param $messages Mixed: List of messages associated with this module. May either be an
 734          *     associative array mapping message key to value, or a JSON-encoded message blob containing
 735          *     the same data, wrapped in an XmlJsCode object.
 736          *
 737          * @return string
 738          */
 739         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
 740                 if ( is_string( $scripts ) ) {
 741                         $scripts = new XmlJsCode( "function( $ ) {{$scripts}}" );
 742                 } elseif ( !is_array( $scripts ) ) {
 743                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
 744                 }
 745                 return Xml::encodeJsCall(
 746                         'mw.loader.implement',
 747                         array(
 748                                 $name,
 749                                 $scripts,
 750                                 (object)$styles,
 751                                 (object)$messages
 752                         ) );
 753         }
 754
 755         /**
 756          * Returns JS code which, when called, will register a given list of messages.
 757          *
 758          * @param $messages Mixed: Either an associative array mapping message key to value, or a
 759          *     JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
 760          *
 761          * @return string
 762          */
 763         public static function makeMessageSetScript( $messages ) {
 764                 return Xml::encodeJsCall( 'mw.messages.set', array( (object)$messages ) );
 765         }
 766
 767         /**
 768          * Combines an associative array mapping media type to CSS into a
 769          * single stylesheet with @media blocks.
 770          *
 771          * @param $styles Array: List of CSS strings keyed by media type
 772          *
 773          * @return string
 774          */
 775         public static function makeCombinedStyles( array $styles ) {
 776                 $out = '';
 777                 foreach ( $styles as $media => $style ) {
 778                         // Transform the media type based on request params and config
 779                         // The way that this relies on $wgRequest to propagate request params is slightly evil
 780                         $media = OutputPage::transformCssMedia( $media );
 781
 782                         if ( $media === null ) {
 783                                 // Skip
 784                         } elseif ( $media === '' || $media == 'all' ) {
 785                                 // Don't output invalid or frivolous @media statements
 786                                 $out .= "$style\n";
 787                         } else {
 788                                 $out .= "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "\n}\n";
 789                         }
 790                 }
 791                 return $out;
 792         }
 793
 794         /**
 795          * Returns a JS call to mw.loader.state, which sets the state of a
 796          * module or modules to a given value. Has two calling conventions:
 797          *
 798          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
 799          *         Set the state of a single module called $name to $state
 800          *
 801          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
 802          *         Set the state of modules with the given names to the given states
 803          *
 804          * @param $name string
 805          * @param $state
 806          *
 807          * @return string
 808          */
 809         public static function makeLoaderStateScript( $name, $state = null ) {
 810                 if ( is_array( $name ) ) {
 811                         return Xml::encodeJsCall( 'mw.loader.state', array( $name ) );
 812                 } else {
 813                         return Xml::encodeJsCall( 'mw.loader.state', array( $name, $state ) );
 814                 }
 815         }
 816
 817         /**
 818          * Returns JS code which calls the script given by $script. The script will
 819          * be called with local variables name, version, dependencies and group,
 820          * which will have values corresponding to $name, $version, $dependencies
 821          * and $group as supplied.
 822          *
 823          * @param $name String: Module name
 824          * @param $version Integer: Module version number as a timestamp
 825          * @param $dependencies Array: List of module names on which this module depends
 826          * @param $group String: Group which the module is in.
 827          * @param $source String: Source of the module, or 'local' if not foreign.
 828          * @param $script String: JavaScript code
 829          *
 830          * @return string
 831          */
 832         public static function makeCustomLoaderScript( $name, $version, $dependencies, $group, $source, $script ) {
 833                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 834                 return Xml::encodeJsCall(
 835                         "( function( name, version, dependencies, group, source ) {\n\t$script\n} )",
 836                         array( $name, $version, $dependencies, $group, $source ) );
 837         }
 838
 839         /**
 840          * Returns JS code which calls mw.loader.register with the given
 841          * parameters. Has three calling conventions:
 842          *
 843          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version, $dependencies, $group, $source ):
 844          *       Register a single module.
 845          *
 846          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
 847          *       Register modules with the given names.
 848          *
 849          *   - ResourceLoader::makeLoaderRegisterScript( array(
 850          *        array( $name1, $version1, $dependencies1, $group1, $source1 ),
 851          *        array( $name2, $version2, $dependencies1, $group2, $source2 ),
 852          *        ...
 853          *     ) ):
 854          *        Registers modules with the given names and parameters.
 855          *
 856          * @param $name String: Module name
 857          * @param $version Integer: Module version number as a timestamp
 858          * @param $dependencies Array: List of module names on which this module depends
 859          * @param $group String: group which the module is in.
 860          * @param $source String: source of the module, or 'local' if not foreign
 861          *
 862          * @return string
 863          */
 864         public static function makeLoaderRegisterScript( $name, $version = null,
 865                 $dependencies = null, $group = null, $source = null )
 866         {
 867                 if ( is_array( $name ) ) {
 868                         return Xml::encodeJsCall( 'mw.loader.register', array( $name ) );
 869                 } else {
 870                         $version = (int) $version > 1 ? (int) $version : 1;
 871                         return Xml::encodeJsCall( 'mw.loader.register',
 872                                 array( $name, $version, $dependencies, $group, $source ) );
 873                 }
 874         }
 875
 876         /**
 877          * Returns JS code which calls mw.loader.addSource() with the given
 878          * parameters. Has two calling conventions:
 879          *
 880          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
 881          *       Register a single source
 882          *
 883          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $props1, $id2 => $props2, ... ) );
 884          *       Register sources with the given IDs and properties.
 885          *
 886          * @param $id String: source ID
 887          * @param $properties Array: source properties (see addSource())
 888          *
 889          * @return string
 890          */
 891         public static function makeLoaderSourcesScript( $id, $properties = null ) {
 892                 if ( is_array( $id ) ) {
 893                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id ) );
 894                 } else {
 895                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id, $properties ) );
 896                 }
 897         }
 898
 899         /**
 900          * Returns JS code which runs given JS code if the client-side framework is
 901          * present.
 902          *
 903          * @param $script String: JavaScript code
 904          *
 905          * @return string
 906          */
 907         public static function makeLoaderConditionalScript( $script ) {
 908                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 909                 return "if(window.mw){\n\t$script\n}\n";
 910         }
 911
 912         /**
 913          * Returns JS code which will set the MediaWiki configuration array to
 914          * the given value.
 915          *
 916          * @param $configuration Array: List of configuration values keyed by variable name
 917          *
 918          * @return string
 919          */
 920         public static function makeConfigSetScript( array $configuration ) {
 921                 return Xml::encodeJsCall( 'mw.config.set', array( $configuration ) );
 922         }
 923
 924         /**
 925          * Convert an array of module names to a packed query string.
 926          *
 927          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
 928          * becomes 'foo.bar,baz|bar.baz,quux'
 929          * @param $modules array of module names (strings)
 930          * @return string Packed query string
 931          */
 932         public static function makePackedModulesString( $modules ) {
 933                 $groups = array(); // array( prefix => array( suffixes ) )
 934                 foreach ( $modules as $module ) {
 935                         $pos = strrpos( $module, '.' );
 936                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
 937                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
 938                         $groups[$prefix][] = $suffix;
 939                 }
 940
 941                 $arr = array();
 942                 foreach ( $groups as $prefix => $suffixes ) {
 943                         $p = $prefix === '' ? '' : $prefix . '.';
 944                         $arr[] = $p . implode( ',', $suffixes );
 945                 }
 946                 $str = implode( '|', $arr );
 947                 return $str;
 948         }
 949
 950         /**
 951          * Determine whether debug mode was requested
 952          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
 953          * @return bool
 954          */
 955         public static function inDebugMode() {
 956                 global $wgRequest, $wgResourceLoaderDebug;
 957                 static $retval = null;
 958                 if ( !is_null( $retval ) ) {
 959                         return $retval;
 960                 }
 961                 return $retval = $wgRequest->getFuzzyBool( 'debug',
 962                         $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug ) );
 963         }
 964
 965         /**
 966          * Build a load.php URL
 967          * @param $modules array of module names (strings)
 968          * @param $lang string Language code
 969          * @param $skin string Skin name
 970          * @param $user string|null User name. If null, the &user= parameter is omitted
 971          * @param $version string|null Versioning timestamp
 972          * @param $debug bool Whether the request should be in debug mode
 973          * @param $only string|null &only= parameter
 974          * @param $printable bool Printable mode
 975          * @param $handheld bool Handheld mode
 976          * @param $extraQuery array Extra query parameters to add
 977          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
 978          */
 979         public static function makeLoaderURL( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
 980                         $printable = false, $handheld = false, $extraQuery = array() ) {
 981                 global $wgLoadScript;
 982                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
 983                         $only, $printable, $handheld, $extraQuery
 984                 );
 985
 986                 // Prevent the IE6 extension check from being triggered (bug 28840)
 987                 // by appending a character that's invalid in Windows extensions ('*')
 988                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
 989         }
 990
 991         /**
 992          * Build a query array (array representation of query string) for load.php. Helper
 993          * function for makeLoaderURL().
 994          * @return array
 995          */
 996         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
 997                         $printable = false, $handheld = false, $extraQuery = array() ) {
 998                 $query = array(
 999                         'modules' => self::makePackedModulesString( $modules ),
1000                         'lang' => $lang,
1001                         'skin' => $skin,
1002                         'debug' => $debug ? 'true' : 'false',
1003                 );
1004                 if ( $user !== null ) {
1005                         $query['user'] = $user;
1006                 }
1007                 if ( $version !== null ) {
1008                         $query['version'] = $version;
1009                 }
1010                 if ( $only !== null ) {
1011                         $query['only'] = $only;
1012                 }
1013                 if ( $printable ) {
1014                         $query['printable'] = 1;
1015                 }
1016                 if ( $handheld ) {
1017                         $query['handheld'] = 1;
1018                 }
1019                 $query += $extraQuery;
1020
1021                 // Make queries uniform in order
1022                 ksort( $query );
1023                 return $query;
1024         }
1025 }