includes/registration/ExtensionRegistry.php

   1 <?php
   2
   3 use MediaWiki\MediaWikiServices;
   4
   5 /**
   6  * ExtensionRegistry class
   7  *
   8  * The Registry loads JSON files, and uses a Processor
   9  * to extract information from them. It also registers
  10  * classes with the autoloader.
  11  *
  12  * @since 1.25
  13  */
  14 class ExtensionRegistry {
  15
  16         /**
  17          * "requires" key that applies to MediaWiki core/$wgVersion
  18          */
  19         const MEDIAWIKI_CORE = 'MediaWiki';
  20
  21         /**
  22          * Version of the highest supported manifest version
  23          * Note: Update MANIFEST_VERSION_MW_VERSION when changing this
  24          */
  25         const MANIFEST_VERSION = 2;
  26
  27         /**
  28          * MediaWiki version constraint representing what the current
  29          * highest MANIFEST_VERSION is supported in
  30          */
  31         const MANIFEST_VERSION_MW_VERSION = '>= 1.29.0';
  32
  33         /**
  34          * Version of the oldest supported manifest version
  35          */
  36         const OLDEST_MANIFEST_VERSION = 1;
  37
  38         /**
  39          * Bump whenever the registration cache needs resetting
  40          */
  41         const CACHE_VERSION = 6;
  42
  43         /**
  44          * Special key that defines the merge strategy
  45          *
  46          * @since 1.26
  47          */
  48         const MERGE_STRATEGY = '_merge_strategy';
  49
  50         /**
  51          * Array of loaded things, keyed by name, values are credits information
  52          *
  53          * @var array
  54          */
  55         private $loaded = [];
  56
  57         /**
  58          * List of paths that should be loaded
  59          *
  60          * @var array
  61          */
  62         protected $queued = [];
  63
  64         /**
  65          * Whether we are done loading things
  66          *
  67          * @var bool
  68          */
  69         private $finished = false;
  70
  71         /**
  72          * Items in the JSON file that aren't being
  73          * set as globals
  74          *
  75          * @var array
  76          */
  77         protected $attributes = [];
  78
  79         /**
  80          * @var ExtensionRegistry
  81          */
  82         private static $instance;
  83
  84         /**
  85          * @return ExtensionRegistry
  86          */
  87         public static function getInstance() {
  88                 if ( self::$instance === null ) {
  89                         self::$instance = new self();
  90                 }
  91
  92                 return self::$instance;
  93         }
  94
  95         /**
  96          * @param string $path Absolute path to the JSON file
  97          */
  98         public function queue( $path ) {
  99                 global $wgExtensionInfoMTime;
 100
 101                 $mtime = $wgExtensionInfoMTime;
 102                 if ( $mtime === false ) {
 103                         if ( file_exists( $path ) ) {
 104                                 $mtime = filemtime( $path );
 105                         } else {
 106                                 throw new Exception( "$path does not exist!" );
 107                         }
 108                         if ( !$mtime ) {
 109                                 $err = error_get_last();
 110                                 throw new Exception( "Couldn't stat $path: {$err['message']}" );
 111                         }
 112                 }
 113                 $this->queued[$path] = $mtime;
 114         }
 115
 116         /**
 117          * @throws MWException If the queue is already marked as finished (no further things should
 118          *  be loaded then).
 119          */
 120         public function loadFromQueue() {
 121                 global $wgVersion, $wgDevelopmentWarnings;
 122                 if ( !$this->queued ) {
 123                         return;
 124                 }
 125
 126                 if ( $this->finished ) {
 127                         throw new MWException(
 128                                 "The following paths tried to load late: "
 129                                 . implode( ', ', array_keys( $this->queued ) )
 130                         );
 131                 }
 132
 133                 // A few more things to vary the cache on
 134                 $versions = [
 135                         'registration' => self::CACHE_VERSION,
 136                         'mediawiki' => $wgVersion
 137                 ];
 138
 139                 // We use a try/catch because we don't want to fail here
 140                 // if $wgObjectCaches is not configured properly for APC setup
 141                 try {
 142                         $cache = MediaWikiServices::getInstance()->getLocalServerObjectCache();
 143                 } catch ( MWException $e ) {
 144                         $cache = new EmptyBagOStuff();
 145                 }
 146                 // See if this queue is in APC
 147                 $key = $cache->makeKey(
 148                         'registration',
 149                         md5( json_encode( $this->queued + $versions ) )
 150                 );
 151                 $data = $cache->get( $key );
 152                 if ( $data ) {
 153                         $this->exportExtractedData( $data );
 154                 } else {
 155                         $data = $this->readFromQueue( $this->queued );
 156                         $this->exportExtractedData( $data );
 157                         // Do this late since we don't want to extract it since we already
 158                         // did that, but it should be cached
 159                         $data['globals']['wgAutoloadClasses'] += $data['autoload'];
 160                         unset( $data['autoload'] );
 161                         if ( !( $data['warnings'] && $wgDevelopmentWarnings ) ) {
 162                                 // If there were no warnings that were shown, cache it
 163                                 $cache->set( $key, $data, 60 * 60 * 24 );
 164                         }
 165                 }
 166                 $this->queued = [];
 167         }
 168
 169         /**
 170          * Get the current load queue. Not intended to be used
 171          * outside of the installer.
 172          *
 173          * @return array
 174          */
 175         public function getQueue() {
 176                 return $this->queued;
 177         }
 178
 179         /**
 180          * Clear the current load queue. Not intended to be used
 181          * outside of the installer.
 182          */
 183         public function clearQueue() {
 184                 $this->queued = [];
 185         }
 186
 187         /**
 188          * After this is called, no more extensions can be loaded
 189          *
 190          * @since 1.29
 191          */
 192         public function finish() {
 193                 $this->finished = true;
 194         }
 195
 196         /**
 197          * Process a queue of extensions and return their extracted data
 198          *
 199          * @param array $queue keys are filenames, values are ignored
 200          * @return array extracted info
 201          * @throws Exception
 202          */
 203         public function readFromQueue( array $queue ) {
 204                 global $wgVersion;
 205                 $autoloadClasses = [];
 206                 $autoloadNamespaces = [];
 207                 $autoloaderPaths = [];
 208                 $processor = new ExtensionProcessor();
 209                 $versionChecker = new VersionChecker( $wgVersion );
 210                 $extDependencies = [];
 211                 $incompatible = [];
 212                 $warnings = false;
 213                 foreach ( $queue as $path => $mtime ) {
 214                         $json = file_get_contents( $path );
 215                         if ( $json === false ) {
 216                                 throw new Exception( "Unable to read $path, does it exist?" );
 217                         }
 218                         $info = json_decode( $json, /* $assoc = */ true );
 219                         if ( !is_array( $info ) ) {
 220                                 throw new Exception( "$path is not a valid JSON file." );
 221                         }
 222
 223                         if ( !isset( $info['manifest_version'] ) ) {
 224                                 wfDeprecated(
 225                                         "{$info['name']}'s extension.json or skin.json does not have manifest_version",
 226                                         '1.29'
 227                                 );
 228                                 $warnings = true;
 229                                 // For backwards-compatability, assume a version of 1
 230                                 $info['manifest_version'] = 1;
 231                         }
 232                         $version = $info['manifest_version'];
 233                         if ( $version < self::OLDEST_MANIFEST_VERSION || $version > self::MANIFEST_VERSION ) {
 234                                 $incompatible[] = "$path: unsupported manifest_version: {$version}";
 235                         }
 236
 237                         $dir = dirname( $path );
 238                         if ( isset( $info['AutoloadClasses'] ) ) {
 239                                 $autoload = $this->processAutoLoader( $dir, $info['AutoloadClasses'] );
 240                                 $GLOBALS['wgAutoloadClasses'] += $autoload;
 241                                 $autoloadClasses += $autoload;
 242                         }
 243                         if ( isset( $info['AutoloadNamespaces'] ) ) {
 244                                 $autoloadNamespaces += $this->processAutoLoader( $dir, $info['AutoloadNamespaces'] );
 245                         }
 246
 247                         // get all requirements/dependencies for this extension
 248                         $requires = $processor->getRequirements( $info );
 249
 250                         // validate the information needed and add the requirements
 251                         if ( is_array( $requires ) && $requires && isset( $info['name'] ) ) {
 252                                 $extDependencies[$info['name']] = $requires;
 253                         }
 254
 255                         // Get extra paths for later inclusion
 256                         $autoloaderPaths = array_merge( $autoloaderPaths,
 257                                 $processor->getExtraAutoloaderPaths( $dir, $info ) );
 258                         // Compatible, read and extract info
 259                         $processor->extractInfo( $path, $info, $version );
 260                 }
 261                 $data = $processor->getExtractedInfo();
 262                 $data['warnings'] = $warnings;
 263
 264                 // check for incompatible extensions
 265                 $incompatible = array_merge(
 266                         $incompatible,
 267                         $versionChecker
 268                                 ->setLoadedExtensionsAndSkins( $data['credits'] )
 269                                 ->checkArray( $extDependencies )
 270                 );
 271
 272                 if ( $incompatible ) {
 273                         if ( count( $incompatible ) === 1 ) {
 274                                 throw new Exception( $incompatible[0] );
 275                         } else {
 276                                 throw new Exception( implode( "\n", $incompatible ) );
 277                         }
 278                 }
 279
 280                 // Need to set this so we can += to it later
 281                 $data['globals']['wgAutoloadClasses'] = [];
 282                 $data['autoload'] = $autoloadClasses;
 283                 $data['autoloaderPaths'] = $autoloaderPaths;
 284                 $data['autoloaderNS'] = $autoloadNamespaces;
 285                 return $data;
 286         }
 287
 288         protected function exportExtractedData( array $info ) {
 289                 foreach ( $info['globals'] as $key => $val ) {
 290                         // If a merge strategy is set, read it and remove it from the value
 291                         // so it doesn't accidentally end up getting set.
 292                         if ( is_array( $val ) && isset( $val[self::MERGE_STRATEGY] ) ) {
 293                                 $mergeStrategy = $val[self::MERGE_STRATEGY];
 294                                 unset( $val[self::MERGE_STRATEGY] );
 295                         } else {
 296                                 $mergeStrategy = 'array_merge';
 297                         }
 298
 299                         // Optimistic: If the global is not set, or is an empty array, replace it entirely.
 300                         // Will be O(1) performance.
 301                         if ( !array_key_exists( $key, $GLOBALS ) || ( is_array( $GLOBALS[$key] ) && !$GLOBALS[$key] ) ) {
 302                                 $GLOBALS[$key] = $val;
 303                                 continue;
 304                         }
 305
 306                         if ( !is_array( $GLOBALS[$key] ) || !is_array( $val ) ) {
 307                                 // config setting that has already been overridden, don't set it
 308                                 continue;
 309                         }
 310
 311                         switch ( $mergeStrategy ) {
 312                                 case 'array_merge_recursive':
 313                                         $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 314                                         break;
 315                                 case 'array_replace_recursive':
 316                                         $GLOBALS[$key] = array_replace_recursive( $GLOBALS[$key], $val );
 317                                         break;
 318                                 case 'array_plus_2d':
 319                                         $GLOBALS[$key] = wfArrayPlus2d( $GLOBALS[$key], $val );
 320                                         break;
 321                                 case 'array_plus':
 322                                         $GLOBALS[$key] += $val;
 323                                         break;
 324                                 case 'array_merge':
 325                                         $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 326                                         break;
 327                                 default:
 328                                         throw new UnexpectedValueException( "Unknown merge strategy '$mergeStrategy'" );
 329                         }
 330                 }
 331
 332                 if ( isset( $info['autoloaderNS'] ) ) {
 333                         AutoLoader::$psr4Namespaces += $info['autoloaderNS'];
 334                 }
 335
 336                 foreach ( $info['defines'] as $name => $val ) {
 337                         define( $name, $val );
 338                 }
 339                 foreach ( $info['autoloaderPaths'] as $path ) {
 340                         if ( file_exists( $path ) ) {
 341                                 require_once $path;
 342                         }
 343                 }
 344
 345                 $this->loaded += $info['credits'];
 346                 if ( $info['attributes'] ) {
 347                         if ( !$this->attributes ) {
 348                                 $this->attributes = $info['attributes'];
 349                         } else {
 350                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 351                         }
 352                 }
 353
 354                 foreach ( $info['callbacks'] as $name => $cb ) {
 355                         if ( !is_callable( $cb ) ) {
 356                                 if ( is_array( $cb ) ) {
 357                                         $cb = '[ ' . implode( ', ', $cb ) . ' ]';
 358                                 }
 359                                 throw new UnexpectedValueException( "callback '$cb' is not callable" );
 360                         }
 361                         call_user_func( $cb, $info['credits'][$name] );
 362                 }
 363         }
 364
 365         /**
 366          * Loads and processes the given JSON file without delay
 367          *
 368          * If some extensions are already queued, this will load
 369          * those as well.
 370          *
 371          * @param string $path Absolute path to the JSON file
 372          */
 373         public function load( $path ) {
 374                 $this->loadFromQueue(); // First clear the queue
 375                 $this->queue( $path );
 376                 $this->loadFromQueue();
 377         }
 378
 379         /**
 380          * Whether a thing has been loaded
 381          * @param string $name
 382          * @return bool
 383          */
 384         public function isLoaded( $name ) {
 385                 return isset( $this->loaded[$name] );
 386         }
 387
 388         /**
 389          * @param string $name
 390          * @return array
 391          */
 392         public function getAttribute( $name ) {
 393                 if ( isset( $this->attributes[$name] ) ) {
 394                         return $this->attributes[$name];
 395                 } else {
 396                         return [];
 397                 }
 398         }
 399
 400         /**
 401          * Get information about all things
 402          *
 403          * @return array
 404          */
 405         public function getAllThings() {
 406                 return $this->loaded;
 407         }
 408
 409         /**
 410          * Fully expand autoloader paths
 411          *
 412          * @param string $dir
 413          * @param array $files
 414          * @return array
 415          */
 416         protected function processAutoLoader( $dir, array $files ) {
 417                 // Make paths absolute, relative to the JSON file
 418                 foreach ( $files as &$file ) {
 419                         $file = "$dir/$file";
 420                 }
 421                 return $files;
 422         }
 423 }