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