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 = 7;
  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         /** Associative array mapping framework ids to a list of names of test suite modules */
  42         /** like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. ) */
  43         protected $testModuleNames = array();
  44
  45         /** array( 'source-id' => array( 'loadScript' => 'http://.../load.php' ) ) **/
  46         protected $sources = array();
  47
  48         /* Protected Methods */
  49
  50         /**
  51          * Loads information stored in the database about modules.
  52          *
  53          * This method grabs modules dependencies from the database and updates modules
  54          * objects.
  55          *
  56          * This is not inside the module code because it is much faster to
  57          * request all of the information at once than it is to have each module
  58          * requests its own information. This sacrifice of modularity yields a substantial
  59          * performance improvement.
  60          *
  61          * @param $modules Array: List of module names to preload information for
  62          * @param $context ResourceLoaderContext: Context to load the information within
  63          */
  64         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  65                 if ( !count( $modules ) ) {
  66                         return; // or else Database*::select() will explode, plus it's cheaper!
  67                 }
  68                 $dbr = wfGetDB( DB_SLAVE );
  69                 $skin = $context->getSkin();
  70                 $lang = $context->getLanguage();
  71
  72                 // Get file dependency information
  73                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  74                                 'md_module' => $modules,
  75                                 'md_skin' => $skin
  76                         ), __METHOD__
  77                 );
  78
  79                 // Set modules' dependencies
  80                 $modulesWithDeps = array();
  81                 foreach ( $res as $row ) {
  82                         $this->getModule( $row->md_module )->setFileDependencies( $skin,
  83                                 FormatJson::decode( $row->md_deps, true )
  84                         );
  85                         $modulesWithDeps[] = $row->md_module;
  86                 }
  87
  88                 // Register the absence of a dependency row too
  89                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
  90                         $this->getModule( $name )->setFileDependencies( $skin, array() );
  91                 }
  92
  93                 // Get message blob mtimes. Only do this for modules with messages
  94                 $modulesWithMessages = array();
  95                 foreach ( $modules as $name ) {
  96                         if ( count( $this->getModule( $name )->getMessages() ) ) {
  97                                 $modulesWithMessages[] = $name;
  98                         }
  99                 }
 100                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 101                 if ( count( $modulesWithMessages ) ) {
 102                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 103                                         'mr_resource' => $modulesWithMessages,
 104                                         'mr_lang' => $lang
 105                                 ), __METHOD__
 106                         );
 107                         foreach ( $res as $row ) {
 108                                 $this->getModule( $row->mr_resource )->setMsgBlobMtime( $lang,
 109                                         wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 110                                 unset( $modulesWithoutMessages[$row->mr_resource] );
 111                         }
 112                 }
 113                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 114                         $this->getModule( $name )->setMsgBlobMtime( $lang, 0 );
 115                 }
 116         }
 117
 118         /**
 119          * Runs JavaScript or CSS data through a filter, caching the filtered result for future calls.
 120          *
 121          * Available filters are:
 122          *  - minify-js \see JavaScriptMinifier::minify
 123          *  - minify-css \see CSSMin::minify
 124          *
 125          * If $data is empty, only contains whitespace or the filter was unknown,
 126          * $data is returned unmodified.
 127          *
 128          * @param $filter String: Name of filter to run
 129          * @param $data String: Text to filter, such as JavaScript or CSS text
 130          * @return String: Filtered data, or a comment containing an error message
 131          */
 132         protected function filter( $filter, $data ) {
 133                 global $wgResourceLoaderMinifierStatementsOnOwnLine, $wgResourceLoaderMinifierMaxLineLength;
 134                 wfProfileIn( __METHOD__ );
 135
 136                 // For empty/whitespace-only data or for unknown filters, don't perform
 137                 // any caching or processing
 138                 if ( trim( $data ) === ''
 139                         || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) )
 140                 {
 141                         wfProfileOut( __METHOD__ );
 142                         return $data;
 143                 }
 144
 145                 // Try for cache hit
 146                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 147                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 148                 $cache = wfGetCache( CACHE_ANYTHING );
 149                 $cacheEntry = $cache->get( $key );
 150                 if ( is_string( $cacheEntry ) ) {
 151                         wfProfileOut( __METHOD__ );
 152                         return $cacheEntry;
 153                 }
 154
 155                 $result = '';
 156                 // Run the filter - we've already verified one of these will work
 157                 try {
 158                         switch ( $filter ) {
 159                                 case 'minify-js':
 160                                         $result = JavaScriptMinifier::minify( $data,
 161                                                 $wgResourceLoaderMinifierStatementsOnOwnLine,
 162                                                 $wgResourceLoaderMinifierMaxLineLength
 163                                         );
 164                                         $result .= "\n\n/* cache key: $key */\n";
 165                                         break;
 166                                 case 'minify-css':
 167                                         $result = CSSMin::minify( $data );
 168                                         $result .= "\n\n/* cache key: $key */\n";
 169                                         break;
 170                         }
 171
 172                         // Save filtered text to Memcached
 173                         $cache->set( $key, $result );
 174                 } catch ( Exception $exception ) {
 175                         // Return exception as a comment
 176                         $result = $this->makeComment( $exception->__toString() );
 177                 }
 178
 179                 wfProfileOut( __METHOD__ );
 180
 181                 return $result;
 182         }
 183
 184         /* Methods */
 185
 186         /**
 187          * Registers core modules and runs registration hooks.
 188          */
 189         public function __construct() {
 190                 global $IP, $wgResourceModules, $wgResourceLoaderSources, $wgLoadScript, $wgEnableJavaScriptTest;
 191
 192                 wfProfileIn( __METHOD__ );
 193
 194                 // Add 'local' source first
 195                 $this->addSource( 'local', array( 'loadScript' => $wgLoadScript, 'apiScript' => wfScript( 'api' ) ) );
 196
 197                 // Add other sources
 198                 $this->addSource( $wgResourceLoaderSources );
 199
 200                 // Register core modules
 201                 $this->register( include( "$IP/resources/Resources.php" ) );
 202                 // Register extension modules
 203                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 204                 $this->register( $wgResourceModules );
 205
 206                 if ( $wgEnableJavaScriptTest === true ) {
 207                         $this->registerTestModules();
 208                 }
 209
 210
 211                 wfProfileOut( __METHOD__ );
 212         }
 213
 214         /**
 215          * Registers a module with the ResourceLoader system.
 216          *
 217          * @param $name Mixed: Name of module as a string or List of name/object pairs as an array
 218          * @param $info array Module info array. For backwards compatibility with 1.17alpha,
 219          *   this may also be a ResourceLoaderModule object. Optional when using
 220          *   multiple-registration calling style.
 221          * @throws MWException: If a duplicate module registration is attempted
 222          * @throws MWException: If a module name contains illegal characters (pipes or commas)
 223          * @throws MWException: If something other than a ResourceLoaderModule is being registered
 224          * @return Boolean: False if there were any errors, in which case one or more modules were not
 225          *     registered
 226          */
 227         public function register( $name, $info = null ) {
 228                 wfProfileIn( __METHOD__ );
 229
 230                 // Allow multiple modules to be registered in one call
 231                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 232                 foreach ( $registrations as $name => $info ) {
 233                         // Disallow duplicate registrations
 234                         if ( isset( $this->moduleInfos[$name] ) ) {
 235                                 // A module has already been registered by this name
 236                                 throw new MWException(
 237                                         'ResourceLoader duplicate registration error. ' .
 238                                         'Another module has already been registered as ' . $name
 239                                 );
 240                         }
 241
 242                         // Check $name for illegal characters
 243                         if ( preg_match( '/[|,!]/', $name ) ) {
 244                                 throw new MWException( "ResourceLoader module name '$name' is invalid. Names may not contain pipes (|), commas (,) or exclamation marks (!)" );
 245                         }
 246
 247                         // Attach module
 248                         if ( is_object( $info ) ) {
 249                                 // Old calling convention
 250                                 // Validate the input
 251                                 if ( !( $info instanceof ResourceLoaderModule ) ) {
 252                                         throw new MWException( 'ResourceLoader invalid module error. ' .
 253                                                 'Instances of ResourceLoaderModule expected.' );
 254                                 }
 255
 256                                 $this->moduleInfos[$name] = array( 'object' => $info );
 257                                 $info->setName( $name );
 258                                 $this->modules[$name] = $info;
 259                         } else {
 260                                 // New calling convention
 261                                 $this->moduleInfos[$name] = $info;
 262                         }
 263                 }
 264
 265                 wfProfileOut( __METHOD__ );
 266         }
 267
 268         /**
 269          */
 270         public function registerTestModules() {
 271                 global $IP, $wgEnableJavaScriptTest;
 272
 273                 if ( $wgEnableJavaScriptTest !== true ) {
 274                         throw new MWException( 'Attempt to register JavaScript test modules but <tt>$wgEnableJavaScriptTest</tt> is false. Edit your <tt>LocalSettings.php</tt> to enable it.' );
 275                 }
 276
 277                 wfProfileIn( __METHOD__ );
 278
 279                 // Get core test suites
 280                 $testModules = array();
 281                 $testModules['qunit'] = include( "$IP/tests/qunit/QUnitTestResources.php" );
 282                 // Get other test suites (e.g. from extensions)
 283                 wfRunHooks( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 284
 285                 // Add the testrunner (which configures QUnit) to the dependencies.
 286                 // Since it must be ready before any of the test suites are executed.
 287                 foreach( $testModules['qunit'] as $moduleName => $moduleProps ) {
 288                         $testModules['qunit'][$moduleName]['dependencies'][] = 'mediawiki.tests.qunit.testrunner';
 289                 }
 290
 291                 foreach( $testModules as $id => $names ) {
 292                         // Register test modules
 293                         $this->register( $testModules[$id] );
 294
 295                         // Keep track of their names so that they can be loaded together
 296                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 297                 }
 298
 299                 wfProfileOut( __METHOD__ );
 300         }
 301
 302         /**
 303          * Add a foreign source of modules.
 304          *
 305          * Source properties:
 306          * 'loadScript': URL (either fully-qualified or protocol-relative) of load.php for this source
 307          *
 308          * @param $id Mixed: source ID (string), or array( id1 => props1, id2 => props2, ... )
 309          * @param $properties Array: source properties
 310          */
 311         public function addSource( $id, $properties = null) {
 312                 // Allow multiple sources to be registered in one call
 313                 if ( is_array( $id ) ) {
 314                         foreach ( $id as $key => $value ) {
 315                                 $this->addSource( $key, $value );
 316                         }
 317                         return;
 318                 }
 319
 320                 // Disallow duplicates
 321                 if ( isset( $this->sources[$id] ) ) {
 322                         throw new MWException(
 323                                 'ResourceLoader duplicate source addition error. ' .
 324                                 'Another source has already been registered as ' . $id
 325                         );
 326                 }
 327
 328                 // Validate properties
 329                 foreach ( self::$requiredSourceProperties as $prop ) {
 330                         if ( !isset( $properties[$prop] ) ) {
 331                                 throw new MWException( "Required property $prop missing from source ID $id" );
 332                         }
 333                 }
 334
 335                 $this->sources[$id] = $properties;
 336         }
 337
 338         /**
 339          * Get a list of module names
 340          *
 341          * @return Array: List of module names
 342          */
 343         public function getModuleNames() {
 344                 return array_keys( $this->moduleInfos );
 345         }
 346
 347         /**
 348          * Get a list of test module names for one (or all) frameworks.
 349          * If the given framework id is unknkown, or if the in-object variable is not an array,
 350          * then it will return an empty array.
 351          *
 352          * @param $framework String: Optional. Get only the test module names for one
 353          * particular framework.
 354          * @return Array
 355          */
 356         public function getTestModuleNames( $framework = 'all' ) {
 357                 /// @TODO: api siteinfo prop testmodulenames modulenames
 358                 if ( $framework == 'all' ) {
 359                         return $this->testModuleNames;
 360                 } elseif ( isset( $this->testModuleNames[$framework] ) && is_array( $this->testModuleNames[$framework] ) ) {
 361                         return $this->testModuleNames[$framework];
 362                 } else {
 363                         return array();
 364                 }
 365         }
 366
 367         /**
 368          * Get the ResourceLoaderModule object for a given module name.
 369          *
 370          * @param $name String: Module name
 371          * @return ResourceLoaderModule if module has been registered, null otherwise
 372          */
 373         public function getModule( $name ) {
 374                 if ( !isset( $this->modules[$name] ) ) {
 375                         if ( !isset( $this->moduleInfos[$name] ) ) {
 376                                 // No such module
 377                                 return null;
 378                         }
 379                         // Construct the requested object
 380                         $info = $this->moduleInfos[$name];
 381                         if ( isset( $info['object'] ) ) {
 382                                 // Object given in info array
 383                                 $object = $info['object'];
 384                         } else {
 385                                 if ( !isset( $info['class'] ) ) {
 386                                         $class = 'ResourceLoaderFileModule';
 387                                 } else {
 388                                         $class = $info['class'];
 389                                 }
 390                                 $object = new $class( $info );
 391                         }
 392                         $object->setName( $name );
 393                         $this->modules[$name] = $object;
 394                 }
 395
 396                 return $this->modules[$name];
 397         }
 398
 399         /**
 400          * Get the list of sources
 401          *
 402          * @return Array: array( id => array of properties, .. )
 403          */
 404         public function getSources() {
 405                 return $this->sources;
 406         }
 407
 408         /**
 409          * Outputs a response to a resource load-request, including a content-type header.
 410          *
 411          * @param $context ResourceLoaderContext: Context in which a response should be formed
 412          */
 413         public function respond( ResourceLoaderContext $context ) {
 414                 global $wgCacheEpoch, $wgUseFileCache;
 415
 416                 // Use file cache if enabled and available...
 417                 if ( $wgUseFileCache ) {
 418                         $fileCache = ResourceFileCache::newFromContext( $context );
 419                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 420                                 return; // output handled
 421                         }
 422                 }
 423
 424                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 425                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 426                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 427                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 428                 // the whole thing in our own output buffer to be sure the active buffer
 429                 // doesn't use ob_gzhandler.
 430                 // See http://bugs.php.net/bug.php?id=36514
 431                 ob_start();
 432
 433                 wfProfileIn( __METHOD__ );
 434                 $errors = '';
 435
 436                 // Split requested modules into two groups, modules and missing
 437                 $modules = array();
 438                 $missing = array();
 439                 foreach ( $context->getModules() as $name ) {
 440                         if ( isset( $this->moduleInfos[$name] ) ) {
 441                                 $module = $this->getModule( $name );
 442                                 // Do not allow private modules to be loaded from the web.
 443                                 // This is a security issue, see bug 34907.
 444                                 if ( $module->getGroup() === 'private' ) {
 445                                         $errors .= $this->makeComment( "Cannot show private module \"$name\"" );
 446                                         continue;
 447                                 }
 448                                 $modules[$name] = $this->getModule( $name );
 449                         } else {
 450                                 $missing[] = $name;
 451                         }
 452                 }
 453
 454                 // Preload information needed to the mtime calculation below
 455                 try {
 456                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 457                 } catch( Exception $e ) {
 458                         // Add exception to the output as a comment
 459                         $errors .= $this->makeComment( $e->__toString() );
 460                 }
 461
 462                 wfProfileIn( __METHOD__.'-getModifiedTime' );
 463
 464                 // To send Last-Modified and support If-Modified-Since, we need to detect
 465                 // the last modified time
 466                 $mtime = wfTimestamp( TS_UNIX, $wgCacheEpoch );
 467                 foreach ( $modules as $module ) {
 468                         /**
 469                          * @var $module ResourceLoaderModule
 470                          */
 471                         try {
 472                                 // Calculate maximum modified time
 473                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 474                         } catch ( Exception $e ) {
 475                                 // Add exception to the output as a comment
 476                                 $errors .= $this->makeComment( $e->__toString() );
 477                         }
 478                 }
 479
 480                 wfProfileOut( __METHOD__.'-getModifiedTime' );
 481
 482                 // Send content type and cache related headers
 483                 $this->sendResponseHeaders( $context, $mtime );
 484
 485                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 486                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 487                         wfProfileOut( __METHOD__ );
 488                         return; // output handled (buffers cleared)
 489                 }
 490
 491                 // Generate a response
 492                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 493
 494                 // Prepend comments indicating exceptions
 495                 $response = $errors . $response;
 496
 497                 // Capture any PHP warnings from the output buffer and append them to the
 498                 // response in a comment if we're in debug mode.
 499                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 500                         $response = $this->makeComment( $warnings ) . $response;
 501                 }
 502
 503                 // Save response to file cache unless there are errors
 504                 if ( isset( $fileCache ) && !$errors && !$missing ) {
 505                         // Cache single modules...and other requests if there are enough hits
 506                         if ( ResourceFileCache::useFileCache( $context ) ) {
 507                                 if ( $fileCache->isCacheWorthy() ) {
 508                                         $fileCache->saveText( $response );
 509                                 } else {
 510                                         $fileCache->incrMissesRecent( $context->getRequest() );
 511                                 }
 512                         }
 513                 }
 514
 515                 // Remove the output buffer and output the response
 516                 ob_end_clean();
 517                 echo $response;
 518
 519                 wfProfileOut( __METHOD__ );
 520         }
 521
 522         /**
 523          * Send content type and last modified headers to the client.
 524          * @param $context ResourceLoaderContext
 525          * @param $mtime string TS_MW timestamp to use for last-modified
 526          * @return void
 527          */
 528         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime ) {
 529                 global $wgResourceLoaderMaxage;
 530                 // If a version wasn't specified we need a shorter expiry time for updates
 531                 // to propagate to clients quickly
 532                 if ( is_null( $context->getVersion() ) ) {
 533                         $maxage  = $wgResourceLoaderMaxage['unversioned']['client'];
 534                         $smaxage = $wgResourceLoaderMaxage['unversioned']['server'];
 535                 // If a version was specified we can use a longer expiry time since changing
 536                 // version numbers causes cache misses
 537                 } else {
 538                         $maxage  = $wgResourceLoaderMaxage['versioned']['client'];
 539                         $smaxage = $wgResourceLoaderMaxage['versioned']['server'];
 540                 }
 541                 if ( $context->getOnly() === 'styles' ) {
 542                         header( 'Content-Type: text/css; charset=utf-8' );
 543                 } else {
 544                         header( 'Content-Type: text/javascript; charset=utf-8' );
 545                 }
 546                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 547                 if ( $context->getDebug() ) {
 548                         // Do not cache debug responses
 549                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 550                         header( 'Pragma: no-cache' );
 551                 } else {
 552                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 553                         $exp = min( $maxage, $smaxage );
 554                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 555                 }
 556         }
 557
 558         /**
 559          * If there's an If-Modified-Since header, respond with a 304 appropriately
 560          * and clear out the output buffer. If the client cache is too old then do nothing.
 561          * @param $context ResourceLoaderContext
 562          * @param $mtime string The TS_MW timestamp to check the header against
 563          * @return bool True iff 304 header sent and output handled
 564          */
 565         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 566                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 567                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 568                 // so we get a valid timestamp.
 569                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 570                 // Never send 304s in debug mode
 571                 if ( $ims !== false && !$context->getDebug() ) {
 572                         $imsTS = strtok( $ims, ';' );
 573                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 574                                 // There's another bug in ob_gzhandler (see also the comment at
 575                                 // the top of this function) that causes it to gzip even empty
 576                                 // responses, meaning it's impossible to produce a truly empty
 577                                 // response (because the gzip header is always there). This is
 578                                 // a problem because 304 responses have to be completely empty
 579                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 580                                 // See also http://bugs.php.net/bug.php?id=51579
 581                                 // To work around this, we tear down all output buffering before
 582                                 // sending the 304.
 583                                 // On some setups, ob_get_level() doesn't seem to go down to zero
 584                                 // no matter how often we call ob_get_clean(), so instead of doing
 585                                 // the more intuitive while ( ob_get_level() > 0 ) ob_get_clean();
 586                                 // we have to be safe here and avoid an infinite loop.
 587                                 for ( $i = 0; $i < ob_get_level(); $i++ ) {
 588                                         ob_end_clean();
 589                                 }
 590
 591                                 header( 'HTTP/1.0 304 Not Modified' );
 592                                 header( 'Status: 304 Not Modified' );
 593                                 return true;
 594                         }
 595                 }
 596                 return false;
 597         }
 598
 599         /**
 600          * Send out code for a response from file cache if possible
 601          *
 602          * @param $fileCache ObjectFileCache: Cache object for this request URL
 603          * @param $context ResourceLoaderContext: Context in which to generate a response
 604          * @return bool If this found a cache file and handled the response
 605          */
 606         protected function tryRespondFromFileCache(
 607                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 608         ) {
 609                 global $wgResourceLoaderMaxage;
 610                 // Buffer output to catch warnings.
 611                 ob_start();
 612                 // Get the maximum age the cache can be
 613                 $maxage = is_null( $context->getVersion() )
 614                         ? $wgResourceLoaderMaxage['unversioned']['server']
 615                         : $wgResourceLoaderMaxage['versioned']['server'];
 616                 // Minimum timestamp the cache file must have
 617                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 618                 if ( !$good ) {
 619                         try { // RL always hits the DB on file cache miss...
 620                                 wfGetDB( DB_SLAVE );
 621                         } catch( DBConnectionError $e ) { // ...check if we need to fallback to cache
 622                                 $good = $fileCache->isCacheGood(); // cache existence check
 623                         }
 624                 }
 625                 if ( $good ) {
 626                         $ts = $fileCache->cacheTimestamp();
 627                         // Send content type and cache headers
 628                         $this->sendResponseHeaders( $context, $ts, false );
 629                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 630                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 631                                 return false; // output handled (buffers cleared)
 632                         }
 633                         $response = $fileCache->fetchText();
 634                         // Capture any PHP warnings from the output buffer and append them to the
 635                         // response in a comment if we're in debug mode.
 636                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 637                                 $response = "/*\n$warnings\n*/\n" . $response;
 638                         }
 639                         // Remove the output buffer and output the response
 640                         ob_end_clean();
 641                         echo $response . "\n/* Cached {$ts} */";
 642                         return true; // cache hit
 643                 }
 644                 // Clear buffer
 645                 ob_end_clean();
 646
 647                 return false; // cache miss
 648         }
 649
 650         protected function makeComment( $text ) {
 651                 $encText = str_replace( '*/', '* /', $text );
 652                 return "/*\n$encText\n*/\n";
 653         }
 654
 655         /**
 656          * Generates code for a response
 657          *
 658          * @param $context ResourceLoaderContext: Context in which to generate a response
 659          * @param $modules Array: List of module objects keyed by module name
 660          * @param $missing Array: List of unavailable modules (optional)
 661          * @return String: Response data
 662          */
 663         public function makeModuleResponse( ResourceLoaderContext $context,
 664                 array $modules, $missing = array() )
 665         {
 666                 $out = '';
 667                 $exceptions = '';
 668                 if ( $modules === array() && $missing === array() ) {
 669                         return '/* No modules requested. Max made me put this here */';
 670                 }
 671
 672                 wfProfileIn( __METHOD__ );
 673                 // Pre-fetch blobs
 674                 if ( $context->shouldIncludeMessages() ) {
 675                         try {
 676                                 $blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
 677                         } catch ( Exception $e ) {
 678                                 // Add exception to the output as a comment
 679                                 $exceptions .= $this->makeComment( $e->__toString() );
 680                         }
 681                 } else {
 682                         $blobs = array();
 683                 }
 684
 685                 // Generate output
 686                 foreach ( $modules as $name => $module ) {
 687                         /**
 688                          * @var $module ResourceLoaderModule
 689                          */
 690
 691                         wfProfileIn( __METHOD__ . '-' . $name );
 692                         try {
 693                                 $scripts = '';
 694                                 if ( $context->shouldIncludeScripts() ) {
 695                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 696                                         // However, we can't do this if the module doesn't support it
 697                                         // We also can't do this if there is an only= parameter, because we have to give
 698                                         // the module a way to return a load.php URL without causing an infinite loop
 699                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 700                                                 $scripts = $module->getScriptURLsForDebug( $context );
 701                                         } else {
 702                                                 $scripts = $module->getScript( $context );
 703                                                 if ( is_string( $scripts ) ) {
 704                                                         // bug 27054: Append semicolon to prevent weird bugs
 705                                                         // caused by files not terminating their statements right
 706                                                         $scripts .= ";\n";
 707                                                 }
 708                                         }
 709                                 }
 710                                 // Styles
 711                                 $styles = array();
 712                                 if ( $context->shouldIncludeStyles() ) {
 713                                         // If we are in debug mode, we'll want to return an array of URLs
 714                                         // See comment near shouldIncludeScripts() for more details
 715                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 716                                                 $styles = $module->getStyleURLsForDebug( $context );
 717                                         } else {
 718                                                 $styles = $module->getStyles( $context );
 719                                         }
 720                                 }
 721
 722                                 // Messages
 723                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 724
 725                                 // Append output
 726                                 switch ( $context->getOnly() ) {
 727                                         case 'scripts':
 728                                                 if ( is_string( $scripts ) ) {
 729                                                         // Load scripts raw...
 730                                                         $out .= $scripts;
 731                                                 } elseif ( is_array( $scripts ) ) {
 732                                                         // ...except when $scripts is an array of URLs
 733                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 734                                                 }
 735                                                 break;
 736                                         case 'styles':
 737                                                 $out .= self::makeCombinedStyles( $styles );
 738                                                 break;
 739                                         case 'messages':
 740                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 741                                                 break;
 742                                         default:
 743                                                 // Minify CSS before embedding in mw.loader.implement call
 744                                                 // (unless in debug mode)
 745                                                 if ( !$context->getDebug() ) {
 746                                                         foreach ( $styles as $media => $style ) {
 747                                                                 if ( is_string( $style ) ) {
 748                                                                         $styles[$media] = $this->filter( 'minify-css', $style );
 749                                                                 }
 750                                                         }
 751                                                 }
 752                                                 $out .= self::makeLoaderImplementScript( $name, $scripts, $styles,
 753                                                         new XmlJsCode( $messagesBlob ) );
 754                                                 break;
 755                                 }
 756                         } catch ( Exception $e ) {
 757                                 // Add exception to the output as a comment
 758                                 $exceptions .= $this->makeComment( $e->__toString() );
 759
 760                                 // Register module as missing
 761                                 $missing[] = $name;
 762                                 unset( $modules[$name] );
 763                         }
 764                         wfProfileOut( __METHOD__ . '-' . $name );
 765                 }
 766
 767                 // Update module states
 768                 if ( $context->shouldIncludeScripts() ) {
 769                         // Set the state of modules loaded as only scripts to ready
 770                         if ( count( $modules ) && $context->getOnly() === 'scripts'
 771                                 && !isset( $modules['startup'] ) )
 772                         {
 773                                 $out .= self::makeLoaderStateScript(
 774                                         array_fill_keys( array_keys( $modules ), 'ready' ) );
 775                         }
 776                         // Set the state of modules which were requested but unavailable as missing
 777                         if ( is_array( $missing ) && count( $missing ) ) {
 778                                 $out .= self::makeLoaderStateScript( array_fill_keys( $missing, 'missing' ) );
 779                         }
 780                 }
 781
 782                 if ( !$context->getDebug() ) {
 783                         if ( $context->getOnly() === 'styles' ) {
 784                                 $out = $this->filter( 'minify-css', $out );
 785                         } else {
 786                                 $out = $this->filter( 'minify-js', $out );
 787                         }
 788                 }
 789
 790                 wfProfileOut( __METHOD__ );
 791                 return $exceptions . $out;
 792         }
 793
 794         /* Static Methods */
 795
 796         /**
 797          * Returns JS code to call to mw.loader.implement for a module with
 798          * given properties.
 799          *
 800          * @param $name string Module name
 801          * @param $scripts Mixed: List of URLs to JavaScript files or String of JavaScript code
 802          * @param $styles Mixed: Array of CSS strings keyed by media type, or an array of lists of URLs to
 803          * CSS files keyed by media type
 804          * @param $messages Mixed: List of messages associated with this module. May either be an
 805          *     associative array mapping message key to value, or a JSON-encoded message blob containing
 806          *     the same data, wrapped in an XmlJsCode object.
 807          *
 808          * @return string
 809          */
 810         public static function makeLoaderImplementScript( $name, $scripts, $styles, $messages ) {
 811                 if ( is_string( $scripts ) ) {
 812                         $scripts = new XmlJsCode( "function () {\n{$scripts}\n}" );
 813                 } elseif ( !is_array( $scripts ) ) {
 814                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
 815                 }
 816                 return Xml::encodeJsCall(
 817                         'mw.loader.implement',
 818                         array(
 819                                 $name,
 820                                 $scripts,
 821                                 // Force objects. mw.loader.implement requires them to be javascript objects.
 822                                 // Although these variables are associative arrays, which become javascript
 823                                 // objects through json_encode. In many cases they will be empty arrays, and
 824                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
 825                                 // output javascript "[]" instead of "{}". This fixes that.
 826                                 (object)$styles,
 827                                 (object)$messages
 828                         ) );
 829         }
 830
 831         /**
 832          * Returns JS code which, when called, will register a given list of messages.
 833          *
 834          * @param $messages Mixed: Either an associative array mapping message key to value, or a
 835          *     JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
 836          *
 837          * @return string
 838          */
 839         public static function makeMessageSetScript( $messages ) {
 840                 return Xml::encodeJsCall( 'mw.messages.set', array( (object)$messages ) );
 841         }
 842
 843         /**
 844          * Combines an associative array mapping media type to CSS into a
 845          * single stylesheet with @media blocks.
 846          *
 847          * @param $styles Array: List of CSS strings keyed by media type
 848          *
 849          * @return string
 850          */
 851         public static function makeCombinedStyles( array $styles ) {
 852                 $out = '';
 853                 foreach ( $styles as $media => $style ) {
 854                         // Transform the media type based on request params and config
 855                         // The way that this relies on $wgRequest to propagate request params is slightly evil
 856                         $media = OutputPage::transformCssMedia( $media );
 857
 858                         if ( $media === null ) {
 859                                 // Skip
 860                         } elseif ( $media === '' || $media == 'all' ) {
 861                                 // Don't output invalid or frivolous @media statements
 862                                 $out .= "$style\n";
 863                         } else {
 864                                 $out .= "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "\n}\n";
 865                         }
 866                 }
 867                 return $out;
 868         }
 869
 870         /**
 871          * Returns a JS call to mw.loader.state, which sets the state of a
 872          * module or modules to a given value. Has two calling conventions:
 873          *
 874          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
 875          *         Set the state of a single module called $name to $state
 876          *
 877          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
 878          *         Set the state of modules with the given names to the given states
 879          *
 880          * @param $name string
 881          * @param $state
 882          *
 883          * @return string
 884          */
 885         public static function makeLoaderStateScript( $name, $state = null ) {
 886                 if ( is_array( $name ) ) {
 887                         return Xml::encodeJsCall( 'mw.loader.state', array( $name ) );
 888                 } else {
 889                         return Xml::encodeJsCall( 'mw.loader.state', array( $name, $state ) );
 890                 }
 891         }
 892
 893         /**
 894          * Returns JS code which calls the script given by $script. The script will
 895          * be called with local variables name, version, dependencies and group,
 896          * which will have values corresponding to $name, $version, $dependencies
 897          * and $group as supplied.
 898          *
 899          * @param $name String: Module name
 900          * @param $version Integer: Module version number as a timestamp
 901          * @param $dependencies Array: List of module names on which this module depends
 902          * @param $group String: Group which the module is in.
 903          * @param $source String: Source of the module, or 'local' if not foreign.
 904          * @param $script String: JavaScript code
 905          *
 906          * @return string
 907          */
 908         public static function makeCustomLoaderScript( $name, $version, $dependencies, $group, $source, $script ) {
 909                 $script = str_replace( "\n", "\n\t", trim( $script ) );
 910                 return Xml::encodeJsCall(
 911                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
 912                         array( $name, $version, $dependencies, $group, $source ) );
 913         }
 914
 915         /**
 916          * Returns JS code which calls mw.loader.register with the given
 917          * parameters. Has three calling conventions:
 918          *
 919          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version, $dependencies, $group, $source ):
 920          *       Register a single module.
 921          *
 922          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
 923          *       Register modules with the given names.
 924          *
 925          *   - ResourceLoader::makeLoaderRegisterScript( array(
 926          *        array( $name1, $version1, $dependencies1, $group1, $source1 ),
 927          *        array( $name2, $version2, $dependencies1, $group2, $source2 ),
 928          *        ...
 929          *     ) ):
 930          *        Registers modules with the given names and parameters.
 931          *
 932          * @param $name String: Module name
 933          * @param $version Integer: Module version number as a timestamp
 934          * @param $dependencies Array: List of module names on which this module depends
 935          * @param $group String: group which the module is in.
 936          * @param $source String: source of the module, or 'local' if not foreign
 937          *
 938          * @return string
 939          */
 940         public static function makeLoaderRegisterScript( $name, $version = null,
 941                 $dependencies = null, $group = null, $source = null )
 942         {
 943                 if ( is_array( $name ) ) {
 944                         return Xml::encodeJsCall( 'mw.loader.register', array( $name ) );
 945                 } else {
 946                         $version = (int) $version > 1 ? (int) $version : 1;
 947                         return Xml::encodeJsCall( 'mw.loader.register',
 948                                 array( $name, $version, $dependencies, $group, $source ) );
 949                 }
 950         }
 951
 952         /**
 953          * Returns JS code which calls mw.loader.addSource() with the given
 954          * parameters. Has two calling conventions:
 955          *
 956          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
 957          *       Register a single source
 958          *
 959          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $props1, $id2 => $props2, ... ) );
 960          *       Register sources with the given IDs and properties.
 961          *
 962          * @param $id String: source ID
 963          * @param $properties Array: source properties (see addSource())
 964          *
 965          * @return string
 966          */
 967         public static function makeLoaderSourcesScript( $id, $properties = null ) {
 968                 if ( is_array( $id ) ) {
 969                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id ) );
 970                 } else {
 971                         return Xml::encodeJsCall( 'mw.loader.addSource', array( $id, $properties ) );
 972                 }
 973         }
 974
 975         /**
 976          * Returns JS code which runs given JS code if the client-side framework is
 977          * present.
 978          *
 979          * @param $script String: JavaScript code
 980          *
 981          * @return string
 982          */
 983         public static function makeLoaderConditionalScript( $script ) {
 984                 return "if(window.mw){\n" . trim( $script ) . "\n}";
 985         }
 986
 987         /**
 988          * Returns JS code which will set the MediaWiki configuration array to
 989          * the given value.
 990          *
 991          * @param $configuration Array: List of configuration values keyed by variable name
 992          *
 993          * @return string
 994          */
 995         public static function makeConfigSetScript( array $configuration ) {
 996                 return Xml::encodeJsCall( 'mw.config.set', array( $configuration ) );
 997         }
 998
 999         /**
1000          * Convert an array of module names to a packed query string.
1001          *
1002          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1003          * becomes 'foo.bar,baz|bar.baz,quux'
1004          * @param $modules array of module names (strings)
1005          * @return string Packed query string
1006          */
1007         public static function makePackedModulesString( $modules ) {
1008                 $groups = array(); // array( prefix => array( suffixes ) )
1009                 foreach ( $modules as $module ) {
1010                         $pos = strrpos( $module, '.' );
1011                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1012                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1013                         $groups[$prefix][] = $suffix;
1014                 }
1015
1016                 $arr = array();
1017                 foreach ( $groups as $prefix => $suffixes ) {
1018                         $p = $prefix === '' ? '' : $prefix . '.';
1019                         $arr[] = $p . implode( ',', $suffixes );
1020                 }
1021                 $str = implode( '|', $arr );
1022                 return $str;
1023         }
1024
1025         /**
1026          * Determine whether debug mode was requested
1027          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1028          * @return bool
1029          */
1030         public static function inDebugMode() {
1031                 global $wgRequest, $wgResourceLoaderDebug;
1032                 static $retval = null;
1033                 if ( !is_null( $retval ) ) {
1034                         return $retval;
1035                 }
1036                 return $retval = $wgRequest->getFuzzyBool( 'debug',
1037                         $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug ) );
1038         }
1039
1040         /**
1041          * Build a load.php URL
1042          * @param $modules array of module names (strings)
1043          * @param $lang string Language code
1044          * @param $skin string Skin name
1045          * @param $user string|null User name. If null, the &user= parameter is omitted
1046          * @param $version string|null Versioning timestamp
1047          * @param $debug bool Whether the request should be in debug mode
1048          * @param $only string|null &only= parameter
1049          * @param $printable bool Printable mode
1050          * @param $handheld bool Handheld mode
1051          * @param $extraQuery array Extra query parameters to add
1052          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1053          */
1054         public static function makeLoaderURL( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
1055                         $printable = false, $handheld = false, $extraQuery = array() ) {
1056                 global $wgLoadScript;
1057                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1058                         $only, $printable, $handheld, $extraQuery
1059                 );
1060
1061                 // Prevent the IE6 extension check from being triggered (bug 28840)
1062                 // by appending a character that's invalid in Windows extensions ('*')
1063                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1064         }
1065
1066         /**
1067          * Build a query array (array representation of query string) for load.php. Helper
1068          * function for makeLoaderURL().
1069          * @return array
1070          */
1071         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null, $version = null, $debug = false, $only = null,
1072                         $printable = false, $handheld = false, $extraQuery = array() ) {
1073                 $query = array(
1074                         'modules' => self::makePackedModulesString( $modules ),
1075                         'lang' => $lang,
1076                         'skin' => $skin,
1077                         'debug' => $debug ? 'true' : 'false',
1078                 );
1079                 if ( $user !== null ) {
1080                         $query['user'] = $user;
1081                 }
1082                 if ( $version !== null ) {
1083                         $query['version'] = $version;
1084                 }
1085                 if ( $only !== null ) {
1086                         $query['only'] = $only;
1087                 }
1088                 if ( $printable ) {
1089                         $query['printable'] = 1;
1090                 }
1091                 if ( $handheld ) {
1092                         $query['handheld'] = 1;
1093                 }
1094                 $query += $extraQuery;
1095
1096                 // Make queries uniform in order
1097                 ksort( $query );
1098                 return $query;
1099         }
1100 }