includes/registration/ExtensionRegistry.php

   1 <?php
   2
   3 use Composer\Semver\Semver;
   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 = 7;
  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 $instance;
  83
  84         /**
  85          * @codeCoverageIgnore
  86          * @return ExtensionRegistry
  87          */
  88         public static function getInstance() {
  89                 if ( self::$instance === null ) {
  90                         self::$instance = new self();
  91                 }
  92
  93                 return self::$instance;
  94         }
  95
  96         /**
  97          * @param string $path Absolute path to the JSON file
  98          */
  99         public function queue( $path ) {
 100                 global $wgExtensionInfoMTime;
 101
 102                 $mtime = $wgExtensionInfoMTime;
 103                 if ( $mtime === false ) {
 104                         if ( file_exists( $path ) ) {
 105                                 $mtime = filemtime( $path );
 106                         } else {
 107                                 throw new Exception( "$path does not exist!" );
 108                         }
 109                         // @codeCoverageIgnoreStart
 110                         if ( $mtime === false ) {
 111                                 $err = error_get_last();
 112                                 throw new Exception( "Couldn't stat $path: {$err['message']}" );
 113                                 // @codeCoverageIgnoreEnd
 114                         }
 115                 }
 116                 $this->queued[$path] = $mtime;
 117         }
 118
 119         /**
 120          * @throws MWException If the queue is already marked as finished (no further things should
 121          *  be loaded then).
 122          */
 123         public function loadFromQueue() {
 124                 global $wgVersion, $wgDevelopmentWarnings;
 125                 if ( !$this->queued ) {
 126                         return;
 127                 }
 128
 129                 if ( $this->finished ) {
 130                         throw new MWException(
 131                                 "The following paths tried to load late: "
 132                                 . implode( ', ', array_keys( $this->queued ) )
 133                         );
 134                 }
 135
 136                 // A few more things to vary the cache on
 137                 $versions = [
 138                         'registration' => self::CACHE_VERSION,
 139                         'mediawiki' => $wgVersion
 140                 ];
 141
 142                 // We use a try/catch because we don't want to fail here
 143                 // if $wgObjectCaches is not configured properly for APC setup
 144                 try {
 145                         // Don't use MediaWikiServices here to prevent instantiating it before extensions have
 146                         // been loaded
 147                         $cacheId = ObjectCache::detectLocalServerCache();
 148                         $cache = ObjectCache::newFromId( $cacheId );
 149                 } catch ( InvalidArgumentException $e ) {
 150                         $cache = new EmptyBagOStuff();
 151                 }
 152                 // See if this queue is in APC
 153                 $key = $cache->makeKey(
 154                         'registration',
 155                         md5( json_encode( $this->queued + $versions ) )
 156                 );
 157                 $data = $cache->get( $key );
 158                 if ( $data ) {
 159                         $this->exportExtractedData( $data );
 160                 } else {
 161                         $data = $this->readFromQueue( $this->queued );
 162                         $this->exportExtractedData( $data );
 163                         // Do this late since we don't want to extract it since we already
 164                         // did that, but it should be cached
 165                         $data['globals']['wgAutoloadClasses'] += $data['autoload'];
 166                         unset( $data['autoload'] );
 167                         if ( !( $data['warnings'] && $wgDevelopmentWarnings ) ) {
 168                                 // If there were no warnings that were shown, cache it
 169                                 $cache->set( $key, $data, 60 * 60 * 24 );
 170                         }
 171                 }
 172                 $this->queued = [];
 173         }
 174
 175         /**
 176          * Get the current load queue. Not intended to be used
 177          * outside of the installer.
 178          *
 179          * @return array
 180          */
 181         public function getQueue() {
 182                 return $this->queued;
 183         }
 184
 185         /**
 186          * Clear the current load queue. Not intended to be used
 187          * outside of the installer.
 188          */
 189         public function clearQueue() {
 190                 $this->queued = [];
 191         }
 192
 193         /**
 194          * After this is called, no more extensions can be loaded
 195          *
 196          * @since 1.29
 197          */
 198         public function finish() {
 199                 $this->finished = true;
 200         }
 201
 202         /**
 203          * Process a queue of extensions and return their extracted data
 204          *
 205          * @param array $queue keys are filenames, values are ignored
 206          * @return array extracted info
 207          * @throws Exception
 208          * @throws ExtensionDependencyError
 209          */
 210         public function readFromQueue( array $queue ) {
 211                 global $wgVersion;
 212                 $autoloadClasses = [];
 213                 $autoloadNamespaces = [];
 214                 $autoloaderPaths = [];
 215                 $processor = new ExtensionProcessor();
 216                 $versionChecker = new VersionChecker( $wgVersion );
 217                 $extDependencies = [];
 218                 $incompatible = [];
 219                 $warnings = false;
 220                 foreach ( $queue as $path => $mtime ) {
 221                         $json = file_get_contents( $path );
 222                         if ( $json === false ) {
 223                                 throw new Exception( "Unable to read $path, does it exist?" );
 224                         }
 225                         $info = json_decode( $json, /* $assoc = */ true );
 226                         if ( !is_array( $info ) ) {
 227                                 throw new Exception( "$path is not a valid JSON file." );
 228                         }
 229
 230                         if ( !isset( $info['manifest_version'] ) ) {
 231                                 wfDeprecated(
 232                                         "{$info['name']}'s extension.json or skin.json does not have manifest_version",
 233                                         '1.29'
 234                                 );
 235                                 $warnings = true;
 236                                 // For backwards-compatability, assume a version of 1
 237                                 $info['manifest_version'] = 1;
 238                         }
 239                         $version = $info['manifest_version'];
 240                         if ( $version < self::OLDEST_MANIFEST_VERSION || $version > self::MANIFEST_VERSION ) {
 241                                 $incompatible[] = "$path: unsupported manifest_version: {$version}";
 242                         }
 243
 244                         $dir = dirname( $path );
 245                         if ( isset( $info['AutoloadClasses'] ) ) {
 246                                 $autoload = $this->processAutoLoader( $dir, $info['AutoloadClasses'] );
 247                                 $GLOBALS['wgAutoloadClasses'] += $autoload;
 248                                 $autoloadClasses += $autoload;
 249                         }
 250                         if ( isset( $info['AutoloadNamespaces'] ) ) {
 251                                 $autoloadNamespaces += $this->processAutoLoader( $dir, $info['AutoloadNamespaces'] );
 252                                 AutoLoader::$psr4Namespaces += $autoloadNamespaces;
 253                         }
 254
 255                         // get all requirements/dependencies for this extension
 256                         $requires = $processor->getRequirements( $info );
 257
 258                         // validate the information needed and add the requirements
 259                         if ( is_array( $requires ) && $requires && isset( $info['name'] ) ) {
 260                                 $extDependencies[$info['name']] = $requires;
 261                         }
 262
 263                         // Get extra paths for later inclusion
 264                         $autoloaderPaths = array_merge( $autoloaderPaths,
 265                                 $processor->getExtraAutoloaderPaths( $dir, $info ) );
 266                         // Compatible, read and extract info
 267                         $processor->extractInfo( $path, $info, $version );
 268                 }
 269                 $data = $processor->getExtractedInfo();
 270                 $data['warnings'] = $warnings;
 271
 272                 // check for incompatible extensions
 273                 $incompatible = array_merge(
 274                         $incompatible,
 275                         $versionChecker
 276                                 ->setLoadedExtensionsAndSkins( $data['credits'] )
 277                                 ->checkArray( $extDependencies )
 278                 );
 279
 280                 if ( $incompatible ) {
 281                         throw new ExtensionDependencyError( $incompatible );
 282                 }
 283
 284                 // Need to set this so we can += to it later
 285                 $data['globals']['wgAutoloadClasses'] = [];
 286                 $data['autoload'] = $autoloadClasses;
 287                 $data['autoloaderPaths'] = $autoloaderPaths;
 288                 $data['autoloaderNS'] = $autoloadNamespaces;
 289                 return $data;
 290         }
 291
 292         protected function exportExtractedData( array $info ) {
 293                 foreach ( $info['globals'] as $key => $val ) {
 294                         // If a merge strategy is set, read it and remove it from the value
 295                         // so it doesn't accidentally end up getting set.
 296                         if ( is_array( $val ) && isset( $val[self::MERGE_STRATEGY] ) ) {
 297                                 $mergeStrategy = $val[self::MERGE_STRATEGY];
 298                                 unset( $val[self::MERGE_STRATEGY] );
 299                         } else {
 300                                 $mergeStrategy = 'array_merge';
 301                         }
 302
 303                         // Optimistic: If the global is not set, or is an empty array, replace it entirely.
 304                         // Will be O(1) performance.
 305                         if ( !array_key_exists( $key, $GLOBALS ) || ( is_array( $GLOBALS[$key] ) && !$GLOBALS[$key] ) ) {
 306                                 $GLOBALS[$key] = $val;
 307                                 continue;
 308                         }
 309
 310                         if ( !is_array( $GLOBALS[$key] ) || !is_array( $val ) ) {
 311                                 // config setting that has already been overridden, don't set it
 312                                 continue;
 313                         }
 314
 315                         switch ( $mergeStrategy ) {
 316                                 case 'array_merge_recursive':
 317                                         $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 318                                         break;
 319                                 case 'array_replace_recursive':
 320                                         $GLOBALS[$key] = array_replace_recursive( $GLOBALS[$key], $val );
 321                                         break;
 322                                 case 'array_plus_2d':
 323                                         $GLOBALS[$key] = wfArrayPlus2d( $GLOBALS[$key], $val );
 324                                         break;
 325                                 case 'array_plus':
 326                                         $GLOBALS[$key] += $val;
 327                                         break;
 328                                 case 'array_merge':
 329                                         $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 330                                         break;
 331                                 default:
 332                                         throw new UnexpectedValueException( "Unknown merge strategy '$mergeStrategy'" );
 333                         }
 334                 }
 335
 336                 if ( isset( $info['autoloaderNS'] ) ) {
 337                         AutoLoader::$psr4Namespaces += $info['autoloaderNS'];
 338                 }
 339
 340                 foreach ( $info['defines'] as $name => $val ) {
 341                         define( $name, $val );
 342                 }
 343                 foreach ( $info['autoloaderPaths'] as $path ) {
 344                         if ( file_exists( $path ) ) {
 345                                 require_once $path;
 346                         }
 347                 }
 348
 349                 $this->loaded += $info['credits'];
 350                 if ( $info['attributes'] ) {
 351                         if ( !$this->attributes ) {
 352                                 $this->attributes = $info['attributes'];
 353                         } else {
 354                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 355                         }
 356                 }
 357
 358                 foreach ( $info['callbacks'] as $name => $cb ) {
 359                         if ( !is_callable( $cb ) ) {
 360                                 if ( is_array( $cb ) ) {
 361                                         $cb = '[ ' . implode( ', ', $cb ) . ' ]';
 362                                 }
 363                                 throw new UnexpectedValueException( "callback '$cb' is not callable" );
 364                         }
 365                         call_user_func( $cb, $info['credits'][$name] );
 366                 }
 367         }
 368
 369         /**
 370          * Loads and processes the given JSON file without delay
 371          *
 372          * If some extensions are already queued, this will load
 373          * those as well.
 374          *
 375          * @param string $path Absolute path to the JSON file
 376          */
 377         public function load( $path ) {
 378                 $this->loadFromQueue(); // First clear the queue
 379                 $this->queue( $path );
 380                 $this->loadFromQueue();
 381         }
 382
 383         /**
 384          * Whether a thing has been loaded
 385          * @param string $name
 386          * @param string $constraint The required version constraint for this dependency
 387          * @throws LogicException if a specific contraint is asked for,
 388          *                        but the extension isn't versioned
 389          * @return bool
 390          */
 391         public function isLoaded( $name, $constraint = '*' ) {
 392                 $isLoaded = isset( $this->loaded[$name] );
 393                 if ( $constraint === '*' || !$isLoaded ) {
 394                         return $isLoaded;
 395                 }
 396                 // if a specific constraint is requested, but no version is set, throw an exception
 397                 if ( !isset( $this->loaded[$name]['version'] ) ) {
 398                         $msg = "{$name} does not expose its version, but an extension or a skin"
 399                                         . " requires: {$constraint}.";
 400                         throw new LogicException( $msg );
 401                 }
 402
 403                 return SemVer::satisfies( $this->loaded[$name]['version'], $constraint );
 404         }
 405
 406         /**
 407          * @param string $name
 408          * @return array
 409          */
 410         public function getAttribute( $name ) {
 411                 return $this->attributes[$name] ?? [];
 412         }
 413
 414         /**
 415          * Get information about all things
 416          *
 417          * @return array
 418          */
 419         public function getAllThings() {
 420                 return $this->loaded;
 421         }
 422
 423         /**
 424          * Fully expand autoloader paths
 425          *
 426          * @param string $dir
 427          * @param array $files
 428          * @return array
 429          */
 430         protected function processAutoLoader( $dir, array $files ) {
 431                 // Make paths absolute, relative to the JSON file
 432                 foreach ( $files as &$file ) {
 433                         $file = "$dir/$file";
 434                 }
 435                 return $files;
 436         }
 437 }