includes/registration/ExtensionRegistry.php

   1 <?php
   2
   3 /**
   4  * ExtensionRegistry class
   5  *
   6  * The Registry loads JSON files, and uses a Processor
   7  * to extract information from them. It also registers
   8  * classes with the autoloader.
   9  *
  10  * @since 1.25
  11  */
  12 class ExtensionRegistry {
  13
  14         /**
  15          * "requires" key that applies to MediaWiki core/$wgVersion
  16          */
  17         const MEDIAWIKI_CORE = 'MediaWiki';
  18
  19         /**
  20          * Version of the highest supported manifest version
  21          * Note: Update MANIFEST_VERSION_MW_VERSION when changing this
  22          */
  23         const MANIFEST_VERSION = 2;
  24
  25         /**
  26          * MediaWiki version constraint representing what the current
  27          * highest MANIFEST_VERSION is supported in
  28          */
  29         const MANIFEST_VERSION_MW_VERSION = '>= 1.29.0';
  30
  31         /**
  32          * Version of the oldest supported manifest version
  33          */
  34         const OLDEST_MANIFEST_VERSION = 1;
  35
  36         /**
  37          * Bump whenever the registration cache needs resetting
  38          */
  39         const CACHE_VERSION = 6;
  40
  41         /**
  42          * Special key that defines the merge strategy
  43          *
  44          * @since 1.26
  45          */
  46         const MERGE_STRATEGY = '_merge_strategy';
  47
  48         /**
  49          * Array of loaded things, keyed by name, values are credits information
  50          *
  51          * @var array
  52          */
  53         private $loaded = [];
  54
  55         /**
  56          * List of paths that should be loaded
  57          *
  58          * @var array
  59          */
  60         protected $queued = [];
  61
  62         /**
  63          * Whether we are done loading things
  64          *
  65          * @var bool
  66          */
  67         private $finished = false;
  68
  69         /**
  70          * Items in the JSON file that aren't being
  71          * set as globals
  72          *
  73          * @var array
  74          */
  75         protected $attributes = [];
  76
  77         /**
  78          * @var ExtensionRegistry
  79          */
  80         private static $instance;
  81
  82         /**
  83          * @codeCoverageIgnore
  84          * @return ExtensionRegistry
  85          */
  86         public static function getInstance() {
  87                 if ( self::$instance === null ) {
  88                         self::$instance = new self();
  89                 }
  90
  91                 return self::$instance;
  92         }
  93
  94         /**
  95          * @param string $path Absolute path to the JSON file
  96          */
  97         public function queue( $path ) {
  98                 global $wgExtensionInfoMTime;
  99
 100                 $mtime = $wgExtensionInfoMTime;
 101                 if ( $mtime === false ) {
 102                         if ( file_exists( $path ) ) {
 103                                 $mtime = filemtime( $path );
 104                         } else {
 105                                 throw new Exception( "$path does not exist!" );
 106                         }
 107                         // @codeCoverageIgnoreStart
 108                         if ( !$mtime ) {
 109                                 $err = error_get_last();
 110                                 throw new Exception( "Couldn't stat $path: {$err['message']}" );
 111                                 // @codeCoverageIgnoreEnd
 112                         }
 113                 }
 114                 $this->queued[$path] = $mtime;
 115         }
 116
 117         /**
 118          * @throws MWException If the queue is already marked as finished (no further things should
 119          *  be loaded then).
 120          */
 121         public function loadFromQueue() {
 122                 global $wgVersion, $wgDevelopmentWarnings;
 123                 if ( !$this->queued ) {
 124                         return;
 125                 }
 126
 127                 if ( $this->finished ) {
 128                         throw new MWException(
 129                                 "The following paths tried to load late: "
 130                                 . implode( ', ', array_keys( $this->queued ) )
 131                         );
 132                 }
 133
 134                 // A few more things to vary the cache on
 135                 $versions = [
 136                         'registration' => self::CACHE_VERSION,
 137                         'mediawiki' => $wgVersion
 138                 ];
 139
 140                 // We use a try/catch because we don't want to fail here
 141                 // if $wgObjectCaches is not configured properly for APC setup
 142                 try {
 143                         // Don't use MediaWikiServices here to prevent instantiating it before extensions have
 144                         // been loaded
 145                         $cacheId = ObjectCache::detectLocalServerCache();
 146                         $cache = ObjectCache::newFromId( $cacheId );
 147                 } catch ( MWException $e ) {
 148                         $cache = new EmptyBagOStuff();
 149                 }
 150                 // See if this queue is in APC
 151                 $key = $cache->makeKey(
 152                         'registration',
 153                         md5( json_encode( $this->queued + $versions ) )
 154                 );
 155                 $data = $cache->get( $key );
 156                 if ( $data ) {
 157                         $this->exportExtractedData( $data );
 158                 } else {
 159                         $data = $this->readFromQueue( $this->queued );
 160                         $this->exportExtractedData( $data );
 161                         // Do this late since we don't want to extract it since we already
 162                         // did that, but it should be cached
 163                         $data['globals']['wgAutoloadClasses'] += $data['autoload'];
 164                         unset( $data['autoload'] );
 165                         if ( !( $data['warnings'] && $wgDevelopmentWarnings ) ) {
 166                                 // If there were no warnings that were shown, cache it
 167                                 $cache->set( $key, $data, 60 * 60 * 24 );
 168                         }
 169                 }
 170                 $this->queued = [];
 171         }
 172
 173         /**
 174          * Get the current load queue. Not intended to be used
 175          * outside of the installer.
 176          *
 177          * @return array
 178          */
 179         public function getQueue() {
 180                 return $this->queued;
 181         }
 182
 183         /**
 184          * Clear the current load queue. Not intended to be used
 185          * outside of the installer.
 186          */
 187         public function clearQueue() {
 188                 $this->queued = [];
 189         }
 190
 191         /**
 192          * After this is called, no more extensions can be loaded
 193          *
 194          * @since 1.29
 195          */
 196         public function finish() {
 197                 $this->finished = true;
 198         }
 199
 200         /**
 201          * Process a queue of extensions and return their extracted data
 202          *
 203          * @param array $queue keys are filenames, values are ignored
 204          * @return array extracted info
 205          * @throws Exception
 206          * @throws ExtensionDependencyError
 207          */
 208         public function readFromQueue( array $queue ) {
 209                 global $wgVersion;
 210                 $autoloadClasses = [];
 211                 $autoloadNamespaces = [];
 212                 $autoloaderPaths = [];
 213                 $processor = new ExtensionProcessor();
 214                 $versionChecker = new VersionChecker( $wgVersion );
 215                 $extDependencies = [];
 216                 $incompatible = [];
 217                 $warnings = false;
 218                 foreach ( $queue as $path => $mtime ) {
 219                         $json = file_get_contents( $path );
 220                         if ( $json === false ) {
 221                                 throw new Exception( "Unable to read $path, does it exist?" );
 222                         }
 223                         $info = json_decode( $json, /* $assoc = */ true );
 224                         if ( !is_array( $info ) ) {
 225                                 throw new Exception( "$path is not a valid JSON file." );
 226                         }
 227
 228                         if ( !isset( $info['manifest_version'] ) ) {
 229                                 wfDeprecated(
 230                                         "{$info['name']}'s extension.json or skin.json does not have manifest_version",
 231                                         '1.29'
 232                                 );
 233                                 $warnings = true;
 234                                 // For backwards-compatability, assume a version of 1
 235                                 $info['manifest_version'] = 1;
 236                         }
 237                         $version = $info['manifest_version'];
 238                         if ( $version < self::OLDEST_MANIFEST_VERSION || $version > self::MANIFEST_VERSION ) {
 239                                 $incompatible[] = "$path: unsupported manifest_version: {$version}";
 240                         }
 241
 242                         $dir = dirname( $path );
 243                         if ( isset( $info['AutoloadClasses'] ) ) {
 244                                 $autoload = $this->processAutoLoader( $dir, $info['AutoloadClasses'] );
 245                                 $GLOBALS['wgAutoloadClasses'] += $autoload;
 246                                 $autoloadClasses += $autoload;
 247                         }
 248                         if ( isset( $info['AutoloadNamespaces'] ) ) {
 249                                 $autoloadNamespaces += $this->processAutoLoader( $dir, $info['AutoloadNamespaces'] );
 250                         }
 251
 252                         // get all requirements/dependencies for this extension
 253                         $requires = $processor->getRequirements( $info );
 254
 255                         // validate the information needed and add the requirements
 256                         if ( is_array( $requires ) && $requires && isset( $info['name'] ) ) {
 257                                 $extDependencies[$info['name']] = $requires;
 258                         }
 259
 260                         // Get extra paths for later inclusion
 261                         $autoloaderPaths = array_merge( $autoloaderPaths,
 262                                 $processor->getExtraAutoloaderPaths( $dir, $info ) );
 263                         // Compatible, read and extract info
 264                         $processor->extractInfo( $path, $info, $version );
 265                 }
 266                 $data = $processor->getExtractedInfo();
 267                 $data['warnings'] = $warnings;
 268
 269                 // check for incompatible extensions
 270                 $incompatible = array_merge(
 271                         $incompatible,
 272                         $versionChecker
 273                                 ->setLoadedExtensionsAndSkins( $data['credits'] )
 274                                 ->checkArray( $extDependencies )
 275                 );
 276
 277                 if ( $incompatible ) {
 278                         throw new ExtensionDependencyError( $incompatible );
 279                 }
 280
 281                 // Need to set this so we can += to it later
 282                 $data['globals']['wgAutoloadClasses'] = [];
 283                 $data['autoload'] = $autoloadClasses;
 284                 $data['autoloaderPaths'] = $autoloaderPaths;
 285                 $data['autoloaderNS'] = $autoloadNamespaces;
 286                 return $data;
 287         }
 288
 289         protected function exportExtractedData( array $info ) {
 290                 foreach ( $info['globals'] as $key => $val ) {
 291                         // If a merge strategy is set, read it and remove it from the value
 292                         // so it doesn't accidentally end up getting set.
 293                         if ( is_array( $val ) && isset( $val[self::MERGE_STRATEGY] ) ) {
 294                                 $mergeStrategy = $val[self::MERGE_STRATEGY];
 295                                 unset( $val[self::MERGE_STRATEGY] );
 296                         } else {
 297                                 $mergeStrategy = 'array_merge';
 298                         }
 299
 300                         // Optimistic: If the global is not set, or is an empty array, replace it entirely.
 301                         // Will be O(1) performance.
 302                         if ( !array_key_exists( $key, $GLOBALS ) || ( is_array( $GLOBALS[$key] ) && !$GLOBALS[$key] ) ) {
 303                                 $GLOBALS[$key] = $val;
 304                                 continue;
 305                         }
 306
 307                         if ( !is_array( $GLOBALS[$key] ) || !is_array( $val ) ) {
 308                                 // config setting that has already been overridden, don't set it
 309                                 continue;
 310                         }
 311
 312                         switch ( $mergeStrategy ) {
 313                                 case 'array_merge_recursive':
 314                                         $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 315                                         break;
 316                                 case 'array_replace_recursive':
 317                                         $GLOBALS[$key] = array_replace_recursive( $GLOBALS[$key], $val );
 318                                         break;
 319                                 case 'array_plus_2d':
 320                                         $GLOBALS[$key] = wfArrayPlus2d( $GLOBALS[$key], $val );
 321                                         break;
 322                                 case 'array_plus':
 323                                         $GLOBALS[$key] += $val;
 324                                         break;
 325                                 case 'array_merge':
 326                                         $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 327                                         break;
 328                                 default:
 329                                         throw new UnexpectedValueException( "Unknown merge strategy '$mergeStrategy'" );
 330                         }
 331                 }
 332
 333                 if ( isset( $info['autoloaderNS'] ) ) {
 334                         AutoLoader::$psr4Namespaces += $info['autoloaderNS'];
 335                 }
 336
 337                 foreach ( $info['defines'] as $name => $val ) {
 338                         define( $name, $val );
 339                 }
 340                 foreach ( $info['autoloaderPaths'] as $path ) {
 341                         if ( file_exists( $path ) ) {
 342                                 require_once $path;
 343                         }
 344                 }
 345
 346                 $this->loaded += $info['credits'];
 347                 if ( $info['attributes'] ) {
 348                         if ( !$this->attributes ) {
 349                                 $this->attributes = $info['attributes'];
 350                         } else {
 351                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 352                         }
 353                 }
 354
 355                 foreach ( $info['callbacks'] as $name => $cb ) {
 356                         if ( !is_callable( $cb ) ) {
 357                                 if ( is_array( $cb ) ) {
 358                                         $cb = '[ ' . implode( ', ', $cb ) . ' ]';
 359                                 }
 360                                 throw new UnexpectedValueException( "callback '$cb' is not callable" );
 361                         }
 362                         call_user_func( $cb, $info['credits'][$name] );
 363                 }
 364         }
 365
 366         /**
 367          * Loads and processes the given JSON file without delay
 368          *
 369          * If some extensions are already queued, this will load
 370          * those as well.
 371          *
 372          * @param string $path Absolute path to the JSON file
 373          */
 374         public function load( $path ) {
 375                 $this->loadFromQueue(); // First clear the queue
 376                 $this->queue( $path );
 377                 $this->loadFromQueue();
 378         }
 379
 380         /**
 381          * Whether a thing has been loaded
 382          * @param string $name
 383          * @return bool
 384          */
 385         public function isLoaded( $name ) {
 386                 return isset( $this->loaded[$name] );
 387         }
 388
 389         /**
 390          * @param string $name
 391          * @return array
 392          */
 393         public function getAttribute( $name ) {
 394                 if ( isset( $this->attributes[$name] ) ) {
 395                         return $this->attributes[$name];
 396                 } else {
 397                         return [];
 398                 }
 399         }
 400
 401         /**
 402          * Get information about all things
 403          *
 404          * @return array
 405          */
 406         public function getAllThings() {
 407                 return $this->loaded;
 408         }
 409
 410         /**
 411          * Fully expand autoloader paths
 412          *
 413          * @param string $dir
 414          * @param array $files
 415          * @return array
 416          */
 417         protected function processAutoLoader( $dir, array $files ) {
 418                 // Make paths absolute, relative to the JSON file
 419                 foreach ( $files as &$file ) {
 420                         $file = "$dir/$file";
 421                 }
 422                 return $files;
 423         }
 424 }