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          * @var BagOStuff
  16          */
  17         protected $cache;
  18
  19         /**
  20          * Array of loaded things, keyed by name, values are credits information
  21          *
  22          * @var array
  23          */
  24         private $loaded = array();
  25
  26         /**
  27          * List of paths that should be loaded
  28          *
  29          * @var array
  30          */
  31         protected $queued = array();
  32
  33         /**
  34          * Items in the JSON file that aren't being
  35          * set as globals
  36          *
  37          * @var array
  38          */
  39         protected $attributes = array();
  40
  41         /**
  42          * Processors, 'default' should be set by subclasses in the constructor
  43          *
  44          * @var Processor[]
  45          */
  46         protected $processors = array();
  47
  48         /**
  49          * @var ExtensionRegistry
  50          */
  51         private static $instance;
  52
  53         /**
  54          * @return ExtensionRegistry
  55          */
  56         public static function getInstance() {
  57                 if ( self::$instance === null ) {
  58                         self::$instance = new self();
  59                 }
  60
  61                 return self::$instance;
  62         }
  63
  64         public function __construct() {
  65                 $this->cache = ObjectCache::newAccelerator( array(), CACHE_NONE );
  66         }
  67
  68         /**
  69          * @param string $path Absolute path to the JSON file
  70          */
  71         public function queue( $path ) {
  72                 global $wgExtensionInfoMTime;
  73                 if ( $wgExtensionInfoMTime !== false ) {
  74                         $mtime = $wgExtensionInfoMTime;
  75                 } else {
  76                         $mtime = filemtime( $path );
  77                 }
  78                 $this->queued[$path] = $mtime;
  79         }
  80
  81         public function loadFromQueue() {
  82                 if ( !$this->queued ) {
  83                         return;
  84                 }
  85
  86                 $this->queued = array_unique( $this->queued );
  87
  88                 // See if this queue is in APC
  89                 $key = wfMemcKey( 'registration', md5( json_encode( $this->queued ) ) );
  90                 $data = $this->cache->get( $key );
  91                 if ( $data ) {
  92                         $this->exportExtractedData( $data );
  93                 } else {
  94                         $data = array( 'globals' => array( 'wgAutoloadClasses' => array() ) );
  95                         $autoloadClasses = array();
  96                         foreach ( $this->queued as $path => $mtime ) {
  97                                 $json = file_get_contents( $path );
  98                                 $info = json_decode( $json, /* $assoc = */ true );
  99                                 $autoload = $this->processAutoLoader( dirname( $path ), $info );
 100                                 // Set up the autoloader now so custom processors will work
 101                                 $GLOBALS['wgAutoloadClasses'] += $autoload;
 102                                 $autoloadClasses += $autoload;
 103                                 if ( isset( $info['processor'] ) ) {
 104                                         $processor = $this->getProcessor( $info['processor'] );
 105                                 } else {
 106                                         $processor = $this->getProcessor( 'default' );
 107                                 }
 108                                 $processor->extractInfo( $path, $info );
 109                         }
 110                         foreach ( $this->processors as $processor ) {
 111                                 $data = array_merge_recursive( $data, $processor->getExtractedInfo() );
 112                         }
 113                         foreach ( $data['credits'] as $credit ) {
 114                                 $data['globals']['wgExtensionCredits'][$credit['type']][] = $credit;
 115                         }
 116                         $this->processors = array(); // Reset
 117                         $this->exportExtractedData( $data );
 118                         // Do this late since we don't want to extract it since we already
 119                         // did that, but it should be cached
 120                         $data['globals']['wgAutoloadClasses'] += $autoloadClasses;
 121                         $this->cache->set( $key, $data );
 122                 }
 123                 $this->queued = array();
 124         }
 125
 126         protected function getProcessor( $type ) {
 127                 if ( !isset( $this->processors[$type] ) ) {
 128                         $processor = $type === 'default' ? new ExtensionProcessor() : new $type();
 129                         if ( !$processor instanceof Processor ) {
 130                                 throw new Exception( "$type is not a Processor" );
 131                         }
 132                         $this->processors[$type] = $processor;
 133                 }
 134
 135                 return $this->processors[$type];
 136         }
 137
 138         protected function exportExtractedData( array $info ) {
 139                 foreach ( $info['globals'] as $key => $val ) {
 140                         if ( !isset( $GLOBALS[$key] ) || !$GLOBALS[$key] ) {
 141                                 $GLOBALS[$key] = $val;
 142                         } elseif ( is_array( $GLOBALS[$key] ) && is_array( $val ) ) {
 143                                 $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 144                         } // else case is a config setting where it has already been overriden, so don't set it
 145                 }
 146                 foreach ( $info['defines'] as $name => $val ) {
 147                         define( $name, $val );
 148                 }
 149                 foreach ( $info['callbacks'] as $cb ) {
 150                         call_user_func( $cb );
 151                 }
 152
 153                 $this->loaded += $info['credits'];
 154
 155                 if ( $info['attributes'] ) {
 156                         if ( !$this->attributes ) {
 157                                 $this->attributes = $info['attributes'];
 158                         } else {
 159                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 160                         }
 161                 }
 162         }
 163
 164         /**
 165          * Loads and processes the given JSON file without delay
 166          *
 167          * If some extensions are already queued, this will load
 168          * those as well.
 169          *
 170          * @param string $path Absolute path to the JSON file
 171          */
 172         public function load( $path ) {
 173                 $this->loadFromQueue(); // First clear the queue
 174                 $this->queue( $path );
 175                 $this->loadFromQueue();
 176         }
 177
 178         /**
 179          * Whether a thing has been loaded
 180          * @param string $name
 181          * @return bool
 182          */
 183         public function isLoaded( $name ) {
 184                 return isset( $this->loaded[$name] );
 185         }
 186
 187         /**
 188          * @param string $name
 189          * @return array
 190          */
 191         public function getAttribute( $name ) {
 192                 if ( isset( $this->attributes[$name] ) ) {
 193                         return $this->attributes[$name];
 194                 } else {
 195                         return array();
 196                 }
 197         }
 198
 199         /**
 200          * Get information about all things
 201          *
 202          * @return array
 203          */
 204         public function getAllThings() {
 205                 return $this->loaded;
 206         }
 207
 208         /**
 209          * Mark a thing as loaded
 210          *
 211          * @param string $name
 212          * @param array $credits
 213          */
 214         protected function markLoaded( $name, array $credits ) {
 215                 $this->loaded[$name] = $credits;
 216         }
 217
 218         /**
 219          * Register classes with the autoloader
 220          *
 221          * @param string $dir
 222          * @param array $info
 223          * @return array
 224          */
 225         protected function processAutoLoader( $dir, array $info ) {
 226                 if ( isset( $info['AutoloadClasses'] ) ) {
 227                         // Make paths absolute, relative to the JSON file
 228                         return array_map( function( $file ) use ( $dir ) {
 229                                 return "$dir/$file";
 230                         }, $info['AutoloadClasses'] );
 231                 } else {
 232                         return array();
 233                 }
 234         }
 235
 236         /**
 237          * @param string $filename absolute path to the JSON file
 238          * @param int $mtime modified time of the file
 239          * @return array
 240          */
 241         protected function loadInfoFromFile( $filename, $mtime ) {
 242                 $key = wfMemcKey( 'registry', md5( $filename ) );
 243                 $cached = $this->cache->get( $key );
 244                 if ( isset( $cached['mtime'] ) && $cached['mtime'] === $mtime ) {
 245                         return $cached['info'];
 246                 }
 247
 248                 $contents = file_get_contents( $filename );
 249                 $json = json_decode( $contents, /* $assoc = */ true );
 250                 if ( is_array( $json ) ) {
 251                         $this->cache->set( $key, array( 'mtime' => $mtime, 'info' => $json ) );
 252                 } else {
 253                         // Don't throw an error here, but don't cache it either.
 254                         // @todo log somewhere?
 255                         $json = array();
 256                 }
 257
 258                 return $json;
 259         }
 260 }