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                 // We use a try/catch instead of the $fallback parameter because
  66                 // we don't want to fail here if $wgObjectCaches is not configured
  67                 // properly for APC setup
  68                 try {
  69                         $this->cache = ObjectCache::newAccelerator( array() );
  70                 } catch ( MWException $e ) {
  71                         $this->cache = new EmptyBagOStuff();
  72                 }
  73         }
  74
  75         /**
  76          * @param string $path Absolute path to the JSON file
  77          */
  78         public function queue( $path ) {
  79                 global $wgExtensionInfoMTime;
  80                 if ( $wgExtensionInfoMTime !== false ) {
  81                         $mtime = $wgExtensionInfoMTime;
  82                 } else {
  83                         $mtime = filemtime( $path );
  84                 }
  85                 $this->queued[$path] = $mtime;
  86         }
  87
  88         public function loadFromQueue() {
  89                 if ( !$this->queued ) {
  90                         return;
  91                 }
  92
  93                 $this->queued = array_unique( $this->queued );
  94
  95                 // See if this queue is in APC
  96                 $key = wfMemcKey( 'registration', md5( json_encode( $this->queued ) ) );
  97                 $data = $this->cache->get( $key );
  98                 if ( $data ) {
  99                         $this->exportExtractedData( $data );
 100                 } else {
 101                         $data = $this->readFromQueue( $this->queued );
 102                         $this->exportExtractedData( $data );
 103                         // Do this late since we don't want to extract it since we already
 104                         // did that, but it should be cached
 105                         $data['globals']['wgAutoloadClasses'] += $data['autoload'];
 106                         unset( $data['autoload'] );
 107                         $this->cache->set( $key, $data );
 108                 }
 109                 $this->queued = array();
 110         }
 111
 112         /**
 113          * Process a queue of extensions and return their extracted data
 114          *
 115          * @param array $queue keys are filenames, values are ignored
 116          * @return array extracted info
 117          * @throws Exception
 118          */
 119         public function readFromQueue( array $queue ) {
 120                 $data = array( 'globals' => array( 'wgAutoloadClasses' => array() ) );
 121                 $autoloadClasses = array();
 122                 foreach ( $queue as $path => $mtime ) {
 123                         $json = file_get_contents( $path );
 124                         if ( $json === false ) {
 125                                 throw new Exception( "Unable to read $path, does it exist?" );
 126                         }
 127                         $info = json_decode( $json, /* $assoc = */ true );
 128                         if ( !is_array( $info ) ) {
 129                                 throw new Exception( "$path is not a valid JSON file." );
 130                         }
 131                         $autoload = $this->processAutoLoader( dirname( $path ), $info );
 132                         // Set up the autoloader now so custom processors will work
 133                         $GLOBALS['wgAutoloadClasses'] += $autoload;
 134                         $autoloadClasses += $autoload;
 135                         if ( isset( $info['processor'] ) ) {
 136                                 $processor = $this->getProcessor( $info['processor'] );
 137                         } else {
 138                                 $processor = $this->getProcessor( 'default' );
 139                         }
 140                         $processor->extractInfo( $path, $info );
 141                 }
 142                 foreach ( $this->processors as $processor ) {
 143                         $data = array_merge_recursive( $data, $processor->getExtractedInfo() );
 144                 }
 145                 foreach ( $data['credits'] as $credit ) {
 146                         $data['globals']['wgExtensionCredits'][$credit['type']][] = $credit;
 147                 }
 148                 $this->processors = array(); // Reset
 149                 $data['autoload'] = $autoloadClasses;
 150                 return $data;
 151         }
 152
 153         protected function getProcessor( $type ) {
 154                 if ( !isset( $this->processors[$type] ) ) {
 155                         $processor = $type === 'default' ? new ExtensionProcessor() : new $type();
 156                         if ( !$processor instanceof Processor ) {
 157                                 throw new Exception( "$type is not a Processor" );
 158                         }
 159                         $this->processors[$type] = $processor;
 160                 }
 161
 162                 return $this->processors[$type];
 163         }
 164
 165         protected function exportExtractedData( array $info ) {
 166                 foreach ( $info['globals'] as $key => $val ) {
 167                         if ( !isset( $GLOBALS[$key] ) || !$GLOBALS[$key] ) {
 168                                 $GLOBALS[$key] = $val;
 169                         } elseif ( $key === 'wgHooks' || $key === 'wgExtensionCredits' ) {
 170                                 // Special case $wgHooks and $wgExtensionCredits, which require a recursive merge.
 171                                 // Ideally it would have been taken care of in the first if block though.
 172                                 $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 173                         } elseif ( $key === 'wgGroupPermissions' ) {
 174                                 // First merge individual groups
 175                                 foreach ( $GLOBALS[$key] as $name => &$groupVal ) {
 176                                         if ( isset( $val[$name] ) ) {
 177                                                 $groupVal += $val[$name];
 178                                         }
 179                                 }
 180                                 // Now merge groups that didn't exist yet
 181                                 $GLOBALS[$key] += $val;
 182                         } elseif ( is_array( $GLOBALS[$key] ) && is_array( $val ) ) {
 183                                 $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 184                         } // else case is a config setting where it has already been overriden, so don't set it
 185                 }
 186                 foreach ( $info['defines'] as $name => $val ) {
 187                         define( $name, $val );
 188                 }
 189                 foreach ( $info['callbacks'] as $cb ) {
 190                         call_user_func( $cb );
 191                 }
 192
 193                 $this->loaded += $info['credits'];
 194
 195                 if ( $info['attributes'] ) {
 196                         if ( !$this->attributes ) {
 197                                 $this->attributes = $info['attributes'];
 198                         } else {
 199                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 200                         }
 201                 }
 202         }
 203
 204         /**
 205          * Loads and processes the given JSON file without delay
 206          *
 207          * If some extensions are already queued, this will load
 208          * those as well.
 209          *
 210          * @param string $path Absolute path to the JSON file
 211          */
 212         public function load( $path ) {
 213                 $this->loadFromQueue(); // First clear the queue
 214                 $this->queue( $path );
 215                 $this->loadFromQueue();
 216         }
 217
 218         /**
 219          * Whether a thing has been loaded
 220          * @param string $name
 221          * @return bool
 222          */
 223         public function isLoaded( $name ) {
 224                 return isset( $this->loaded[$name] );
 225         }
 226
 227         /**
 228          * @param string $name
 229          * @return array
 230          */
 231         public function getAttribute( $name ) {
 232                 if ( isset( $this->attributes[$name] ) ) {
 233                         return $this->attributes[$name];
 234                 } else {
 235                         return array();
 236                 }
 237         }
 238
 239         /**
 240          * Get information about all things
 241          *
 242          * @return array
 243          */
 244         public function getAllThings() {
 245                 return $this->loaded;
 246         }
 247
 248         /**
 249          * Mark a thing as loaded
 250          *
 251          * @param string $name
 252          * @param array $credits
 253          */
 254         protected function markLoaded( $name, array $credits ) {
 255                 $this->loaded[$name] = $credits;
 256         }
 257
 258         /**
 259          * Register classes with the autoloader
 260          *
 261          * @param string $dir
 262          * @param array $info
 263          * @return array
 264          */
 265         protected function processAutoLoader( $dir, array $info ) {
 266                 if ( isset( $info['AutoloadClasses'] ) ) {
 267                         // Make paths absolute, relative to the JSON file
 268                         return array_map( function( $file ) use ( $dir ) {
 269                                 return "$dir/$file";
 270                         }, $info['AutoloadClasses'] );
 271                 } else {
 272                         return array();
 273                 }
 274         }
 275 }