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          * Version of the highest supported manifest version
  16          */
  17         const MANIFEST_VERSION = 1;
  18
  19         /**
  20          * Version of the oldest supported manifest version
  21          */
  22         const OLDEST_MANIFEST_VERSION = 1;
  23
  24         /**
  25          * @var BagOStuff
  26          */
  27         protected $cache;
  28
  29         /**
  30          * Array of loaded things, keyed by name, values are credits information
  31          *
  32          * @var array
  33          */
  34         private $loaded = array();
  35
  36         /**
  37          * List of paths that should be loaded
  38          *
  39          * @var array
  40          */
  41         protected $queued = array();
  42
  43         /**
  44          * Items in the JSON file that aren't being
  45          * set as globals
  46          *
  47          * @var array
  48          */
  49         protected $attributes = array();
  50
  51         /**
  52          * @var ExtensionRegistry
  53          */
  54         private static $instance;
  55
  56         /**
  57          * @return ExtensionRegistry
  58          */
  59         public static function getInstance() {
  60                 if ( self::$instance === null ) {
  61                         self::$instance = new self();
  62                 }
  63
  64                 return self::$instance;
  65         }
  66
  67         public function __construct() {
  68                 // We use a try/catch instead of the $fallback parameter because
  69                 // we don't want to fail here if $wgObjectCaches is not configured
  70                 // properly for APC setup
  71                 try {
  72                         $this->cache = ObjectCache::newAccelerator( array() );
  73                 } catch ( MWException $e ) {
  74                         $this->cache = new EmptyBagOStuff();
  75                 }
  76         }
  77
  78         /**
  79          * @param string $path Absolute path to the JSON file
  80          */
  81         public function queue( $path ) {
  82                 global $wgExtensionInfoMTime;
  83
  84                 $mtime = $wgExtensionInfoMTime;
  85                 if ( $mtime === false ) {
  86                         if ( file_exists( $path ) ) {
  87                                 $mtime = filemtime( $path );
  88                         } else {
  89                                 throw new Exception( "$path does not exist!" );
  90                         }
  91                         if ( !$mtime ) {
  92                                 $err = error_get_last();
  93                                 throw new Exception( "Couldn't stat $path: {$err['message']}" );
  94                         }
  95                 }
  96                 $this->queued[$path] = $mtime;
  97         }
  98
  99         public function loadFromQueue() {
 100                 if ( !$this->queued ) {
 101                         return;
 102                 }
 103
 104                 // See if this queue is in APC
 105                 $key = wfMemcKey( 'registration', md5( json_encode( $this->queued ) ) );
 106                 $data = $this->cache->get( $key );
 107                 if ( $data ) {
 108                         $this->exportExtractedData( $data );
 109                 } else {
 110                         $data = $this->readFromQueue( $this->queued );
 111                         $this->exportExtractedData( $data );
 112                         // Do this late since we don't want to extract it since we already
 113                         // did that, but it should be cached
 114                         $data['globals']['wgAutoloadClasses'] += $data['autoload'];
 115                         unset( $data['autoload'] );
 116                         $this->cache->set( $key, $data, 60 * 60 * 24 );
 117                 }
 118                 $this->queued = array();
 119         }
 120
 121         /**
 122          * Process a queue of extensions and return their extracted data
 123          *
 124          * @param array $queue keys are filenames, values are ignored
 125          * @return array extracted info
 126          * @throws Exception
 127          */
 128         public function readFromQueue( array $queue ) {
 129                 $autoloadClasses = array();
 130                 $processor = new ExtensionProcessor();
 131                 foreach ( $queue as $path => $mtime ) {
 132                         $json = file_get_contents( $path );
 133                         if ( $json === false ) {
 134                                 throw new Exception( "Unable to read $path, does it exist?" );
 135                         }
 136                         $info = json_decode( $json, /* $assoc = */ true );
 137                         if ( !is_array( $info ) ) {
 138                                 throw new Exception( "$path is not a valid JSON file." );
 139                         }
 140                         if ( !isset( $info['manifest_version' ] ) ) {
 141                                 // For backwards-compatability, assume a version of 1
 142                                 $info['manifest_version'] = 1;
 143                         }
 144                         $version = $info['manifest_version'];
 145                         if ( $version < self::OLDEST_MANIFEST_VERSION || $version > self::MANIFEST_VERSION ) {
 146                                 throw new Exception( "$path: unsupported manifest_version: {$version}" );
 147                         }
 148                         $autoload = $this->processAutoLoader( dirname( $path ), $info );
 149                         // Set up the autoloader now so custom processors will work
 150                         $GLOBALS['wgAutoloadClasses'] += $autoload;
 151                         $autoloadClasses += $autoload;
 152                         $processor->extractInfo( $path, $info, $version );
 153                 }
 154                 $data = $processor->getExtractedInfo();
 155                 // Need to set this so we can += to it later
 156                 $data['globals']['wgAutoloadClasses'] = array();
 157                 foreach ( $data['credits'] as $credit ) {
 158                         $data['globals']['wgExtensionCredits'][$credit['type']][] = $credit;
 159                 }
 160                 $data['autoload'] = $autoloadClasses;
 161                 return $data;
 162         }
 163
 164         protected function exportExtractedData( array $info ) {
 165                 foreach ( $info['globals'] as $key => $val ) {
 166                         if ( !isset( $GLOBALS[$key] ) || ( is_array( $GLOBALS[$key] ) && !$GLOBALS[$key] ) ) {
 167                                 $GLOBALS[$key] = $val;
 168                         } elseif ( $key === 'wgHooks' || $key === 'wgExtensionCredits' ) {
 169                                 // Special case $wgHooks and $wgExtensionCredits, which require a recursive merge.
 170                                 // Ideally it would have been taken care of in the first if block though.
 171                                 $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 172                         } elseif ( $key === 'wgGroupPermissions' ) {
 173                                 // First merge individual groups
 174                                 foreach ( $GLOBALS[$key] as $name => &$groupVal ) {
 175                                         if ( isset( $val[$name] ) ) {
 176                                                 $groupVal += $val[$name];
 177                                         }
 178                                 }
 179                                 // Now merge groups that didn't exist yet
 180                                 $GLOBALS[$key] += $val;
 181                         } elseif ( is_array( $GLOBALS[$key] ) && is_array( $val ) ) {
 182                                 $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 183                         } // else case is a config setting where it has already been overriden, so don't set it
 184                 }
 185                 foreach ( $info['defines'] as $name => $val ) {
 186                         define( $name, $val );
 187                 }
 188                 foreach ( $info['callbacks'] as $cb ) {
 189                         call_user_func( $cb );
 190                 }
 191
 192                 $this->loaded += $info['credits'];
 193
 194                 if ( $info['attributes'] ) {
 195                         if ( !$this->attributes ) {
 196                                 $this->attributes = $info['attributes'];
 197                         } else {
 198                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 199                         }
 200                 }
 201         }
 202
 203         /**
 204          * Loads and processes the given JSON file without delay
 205          *
 206          * If some extensions are already queued, this will load
 207          * those as well.
 208          *
 209          * @param string $path Absolute path to the JSON file
 210          */
 211         public function load( $path ) {
 212                 $this->loadFromQueue(); // First clear the queue
 213                 $this->queue( $path );
 214                 $this->loadFromQueue();
 215         }
 216
 217         /**
 218          * Whether a thing has been loaded
 219          * @param string $name
 220          * @return bool
 221          */
 222         public function isLoaded( $name ) {
 223                 return isset( $this->loaded[$name] );
 224         }
 225
 226         /**
 227          * @param string $name
 228          * @return array
 229          */
 230         public function getAttribute( $name ) {
 231                 if ( isset( $this->attributes[$name] ) ) {
 232                         return $this->attributes[$name];
 233                 } else {
 234                         return array();
 235                 }
 236         }
 237
 238         /**
 239          * Get information about all things
 240          *
 241          * @return array
 242          */
 243         public function getAllThings() {
 244                 return $this->loaded;
 245         }
 246
 247         /**
 248          * Mark a thing as loaded
 249          *
 250          * @param string $name
 251          * @param array $credits
 252          */
 253         protected function markLoaded( $name, array $credits ) {
 254                 $this->loaded[$name] = $credits;
 255         }
 256
 257         /**
 258          * Register classes with the autoloader
 259          *
 260          * @param string $dir
 261          * @param array $info
 262          * @return array
 263          */
 264         protected function processAutoLoader( $dir, array $info ) {
 265                 if ( isset( $info['AutoloadClasses'] ) ) {
 266                         // Make paths absolute, relative to the JSON file
 267                         return array_map( function( $file ) use ( $dir ) {
 268                                 return "$dir/$file";
 269                         }, $info['AutoloadClasses'] );
 270                 } else {
 271                         return array();
 272                 }
 273         }
 274 }