1c3640752763c969d5f099a56b060fca2cec6295
[lhc/web/wiklou.git] / 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 $data = array( 'globals' => array( 'wgAutoloadClasses' => array() ) );
130 $autoloadClasses = array();
131 $processor = new ExtensionProcessor();
132 foreach ( $queue as $path => $mtime ) {
133 $json = file_get_contents( $path );
134 if ( $json === false ) {
135 throw new Exception( "Unable to read $path, does it exist?" );
136 }
137 $info = json_decode( $json, /* $assoc = */ true );
138 if ( !is_array( $info ) ) {
139 throw new Exception( "$path is not a valid JSON file." );
140 }
141 if ( !isset( $info['manifest_version' ] ) ) {
142 // For backwards-compatability, assume a version of 1
143 $info['manifest_version'] = 1;
144 }
145 $version = $info['manifest_version'];
146 if ( $version < self::OLDEST_MANIFEST_VERSION || $version > self::MANIFEST_VERSION ) {
147 throw new Exception( "$path: unsupported manifest_version: {$version}" );
148 }
149 $autoload = $this->processAutoLoader( dirname( $path ), $info );
150 // Set up the autoloader now so custom processors will work
151 $GLOBALS['wgAutoloadClasses'] += $autoload;
152 $autoloadClasses += $autoload;
153 $processor->extractInfo( $path, $info, $version );
154 }
155 $data = $processor->getExtractedInfo();
156 // Need to set this so we can += to it later
157 $data['globals']['wgAutoloadClasses'] = array();
158 foreach ( $data['credits'] as $credit ) {
159 $data['globals']['wgExtensionCredits'][$credit['type']][] = $credit;
160 }
161 $data['autoload'] = $autoloadClasses;
162 return $data;
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 }