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                 $data = array( 'globals' => array( 'wgAutoloadClasses' => array() ) );
 120                 $autoloadClasses = array();
 121                 $processor = new ExtensionProcessor();
 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                         $processor->extractInfo( $path, $info );
 136                 }
 137                 $data = $processor->getExtractedInfo();
 138                 // Need to set this so we can += to it later
 139                 $data['globals']['wgAutoloadClasses'] = array();
 140                 foreach ( $data['credits'] as $credit ) {
 141                         $data['globals']['wgExtensionCredits'][$credit['type']][] = $credit;
 142                 }
 143                 $data['autoload'] = $autoloadClasses;
 144                 return $data;
 145         }
 146
 147         protected function exportExtractedData( array $info ) {
 148                 foreach ( $info['globals'] as $key => $val ) {
 149                         if ( !isset( $GLOBALS[$key] ) || !$GLOBALS[$key] ) {
 150                                 $GLOBALS[$key] = $val;
 151                         } elseif ( $key === 'wgHooks' || $key === 'wgExtensionCredits' ) {
 152                                 // Special case $wgHooks and $wgExtensionCredits, which require a recursive merge.
 153                                 // Ideally it would have been taken care of in the first if block though.
 154                                 $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
 155                         } elseif ( $key === 'wgGroupPermissions' ) {
 156                                 // First merge individual groups
 157                                 foreach ( $GLOBALS[$key] as $name => &$groupVal ) {
 158                                         if ( isset( $val[$name] ) ) {
 159                                                 $groupVal += $val[$name];
 160                                         }
 161                                 }
 162                                 // Now merge groups that didn't exist yet
 163                                 $GLOBALS[$key] += $val;
 164                         } elseif ( is_array( $GLOBALS[$key] ) && is_array( $val ) ) {
 165                                 $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
 166                         } // else case is a config setting where it has already been overriden, so don't set it
 167                 }
 168                 foreach ( $info['defines'] as $name => $val ) {
 169                         define( $name, $val );
 170                 }
 171                 foreach ( $info['callbacks'] as $cb ) {
 172                         call_user_func( $cb );
 173                 }
 174
 175                 $this->loaded += $info['credits'];
 176
 177                 if ( $info['attributes'] ) {
 178                         if ( !$this->attributes ) {
 179                                 $this->attributes = $info['attributes'];
 180                         } else {
 181                                 $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
 182                         }
 183                 }
 184         }
 185
 186         /**
 187          * Loads and processes the given JSON file without delay
 188          *
 189          * If some extensions are already queued, this will load
 190          * those as well.
 191          *
 192          * @param string $path Absolute path to the JSON file
 193          */
 194         public function load( $path ) {
 195                 $this->loadFromQueue(); // First clear the queue
 196                 $this->queue( $path );
 197                 $this->loadFromQueue();
 198         }
 199
 200         /**
 201          * Whether a thing has been loaded
 202          * @param string $name
 203          * @return bool
 204          */
 205         public function isLoaded( $name ) {
 206                 return isset( $this->loaded[$name] );
 207         }
 208
 209         /**
 210          * @param string $name
 211          * @return array
 212          */
 213         public function getAttribute( $name ) {
 214                 if ( isset( $this->attributes[$name] ) ) {
 215                         return $this->attributes[$name];
 216                 } else {
 217                         return array();
 218                 }
 219         }
 220
 221         /**
 222          * Get information about all things
 223          *
 224          * @return array
 225          */
 226         public function getAllThings() {
 227                 return $this->loaded;
 228         }
 229
 230         /**
 231          * Mark a thing as loaded
 232          *
 233          * @param string $name
 234          * @param array $credits
 235          */
 236         protected function markLoaded( $name, array $credits ) {
 237                 $this->loaded[$name] = $credits;
 238         }
 239
 240         /**
 241          * Register classes with the autoloader
 242          *
 243          * @param string $dir
 244          * @param array $info
 245          * @return array
 246          */
 247         protected function processAutoLoader( $dir, array $info ) {
 248                 if ( isset( $info['AutoloadClasses'] ) ) {
 249                         // Make paths absolute, relative to the JSON file
 250                         return array_map( function( $file ) use ( $dir ) {
 251                                 return "$dir/$file";
 252                         }, $info['AutoloadClasses'] );
 253                 } else {
 254                         return array();
 255                 }
 256         }
 257 }