MediaWiki  1.28.3
ExtensionRegistry.php
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1 <?php
2 
4 
15 
19  const MEDIAWIKI_CORE = 'MediaWiki';
20 
24  const MANIFEST_VERSION = 1;
25 
30 
34  const CACHE_VERSION = 4;
35 
41  const MERGE_STRATEGY = '_merge_strategy';
42 
46  protected $cache;
47 
53  private $loaded = [];
54 
60  protected $queued = [];
61 
68  protected $attributes = [];
69 
73  private static $instance;
74 
78  public static function getInstance() {
79  if ( self::$instance === null ) {
80  self::$instance = new self();
81  }
82 
83  return self::$instance;
84  }
85 
86  public function __construct() {
87  // We use a try/catch because we don't want to fail here
88  // if $wgObjectCaches is not configured properly for APC setup
89  try {
90  $this->cache = MediaWikiServices::getInstance()->getLocalServerObjectCache();
91  } catch ( MWException $e ) {
92  $this->cache = new EmptyBagOStuff();
93  }
94  }
95 
99  public function queue( $path ) {
101 
102  $mtime = $wgExtensionInfoMTime;
103  if ( $mtime === false ) {
104  if ( file_exists( $path ) ) {
105  $mtime = filemtime( $path );
106  } else {
107  throw new Exception( "$path does not exist!" );
108  }
109  if ( !$mtime ) {
110  $err = error_get_last();
111  throw new Exception( "Couldn't stat $path: {$err['message']}" );
112  }
113  }
114  $this->queued[$path] = $mtime;
115  }
116 
117  public function loadFromQueue() {
119  if ( !$this->queued ) {
120  return;
121  }
122 
123  // A few more things to vary the cache on
124  $versions = [
125  'registration' => self::CACHE_VERSION,
126  'mediawiki' => $wgVersion
127  ];
128 
129  // See if this queue is in APC
130  $key = wfMemcKey(
131  'registration',
132  md5( json_encode( $this->queued + $versions ) )
133  );
134  $data = $this->cache->get( $key );
135  if ( $data ) {
136  $this->exportExtractedData( $data );
137  } else {
138  $data = $this->readFromQueue( $this->queued );
139  $this->exportExtractedData( $data );
140  // Do this late since we don't want to extract it since we already
141  // did that, but it should be cached
142  $data['globals']['wgAutoloadClasses'] += $data['autoload'];
143  unset( $data['autoload'] );
144  $this->cache->set( $key, $data, 60 * 60 * 24 );
145  }
146  $this->queued = [];
147  }
148 
155  public function getQueue() {
156  return $this->queued;
157  }
158 
163  public function clearQueue() {
164  $this->queued = [];
165  }
166 
174  public function readFromQueue( array $queue ) {
176  $autoloadClasses = [];
177  $autoloaderPaths = [];
178  $processor = new ExtensionProcessor();
179  $incompatible = [];
180  $coreVersionParser = new CoreVersionChecker( $wgVersion );
181  foreach ( $queue as $path => $mtime ) {
182  $json = file_get_contents( $path );
183  if ( $json === false ) {
184  throw new Exception( "Unable to read $path, does it exist?" );
185  }
186  $info = json_decode( $json, /* $assoc = */ true );
187  if ( !is_array( $info ) ) {
188  throw new Exception( "$path is not a valid JSON file." );
189  }
190  if ( !isset( $info['manifest_version'] ) ) {
191  // For backwards-compatability, assume a version of 1
192  $info['manifest_version'] = 1;
193  }
194  $version = $info['manifest_version'];
195  if ( $version < self::OLDEST_MANIFEST_VERSION || $version > self::MANIFEST_VERSION ) {
196  throw new Exception( "$path: unsupported manifest_version: {$version}" );
197  }
198  $autoload = $this->processAutoLoader( dirname( $path ), $info );
199  // Set up the autoloader now so custom processors will work
200  $GLOBALS['wgAutoloadClasses'] += $autoload;
201  $autoloadClasses += $autoload;
202  // Check any constraints against MediaWiki core
203  $requires = $processor->getRequirements( $info );
204  if ( isset( $requires[self::MEDIAWIKI_CORE] )
205  && !$coreVersionParser->check( $requires[self::MEDIAWIKI_CORE] )
206  ) {
207  // Doesn't match, mark it as incompatible.
208  $incompatible[] = "{$info['name']} is not compatible with the current "
209  . "MediaWiki core (version {$wgVersion}), it requires: " . $requires[self::MEDIAWIKI_CORE]
210  . '.';
211  continue;
212  }
213  // Get extra paths for later inclusion
214  $autoloaderPaths = array_merge( $autoloaderPaths,
215  $processor->getExtraAutoloaderPaths( dirname( $path ), $info ) );
216  // Compatible, read and extract info
217  $processor->extractInfo( $path, $info, $version );
218  }
219  if ( $incompatible ) {
220  if ( count( $incompatible ) === 1 ) {
221  throw new Exception( $incompatible[0] );
222  } else {
223  throw new Exception( implode( "\n", $incompatible ) );
224  }
225  }
226  $data = $processor->getExtractedInfo();
227  // Need to set this so we can += to it later
228  $data['globals']['wgAutoloadClasses'] = [];
229  $data['autoload'] = $autoloadClasses;
230  $data['autoloaderPaths'] = $autoloaderPaths;
231  return $data;
232  }
233 
234  protected function exportExtractedData( array $info ) {
235  foreach ( $info['globals'] as $key => $val ) {
236  // If a merge strategy is set, read it and remove it from the value
237  // so it doesn't accidentally end up getting set.
238  if ( is_array( $val ) && isset( $val[self::MERGE_STRATEGY] ) ) {
239  $mergeStrategy = $val[self::MERGE_STRATEGY];
240  unset( $val[self::MERGE_STRATEGY] );
241  } else {
242  $mergeStrategy = 'array_merge';
243  }
244 
245  // Optimistic: If the global is not set, or is an empty array, replace it entirely.
246  // Will be O(1) performance.
247  if ( !isset( $GLOBALS[$key] ) || ( is_array( $GLOBALS[$key] ) && !$GLOBALS[$key] ) ) {
248  $GLOBALS[$key] = $val;
249  continue;
250  }
251 
252  if ( !is_array( $GLOBALS[$key] ) || !is_array( $val ) ) {
253  // config setting that has already been overridden, don't set it
254  continue;
255  }
256 
257  switch ( $mergeStrategy ) {
258  case 'array_merge_recursive':
259  $GLOBALS[$key] = array_merge_recursive( $GLOBALS[$key], $val );
260  break;
261  case 'array_replace_recursive':
262  $GLOBALS[$key] = array_replace_recursive( $GLOBALS[$key], $val );
263  break;
264  case 'array_plus_2d':
265  $GLOBALS[$key] = wfArrayPlus2d( $GLOBALS[$key], $val );
266  break;
267  case 'array_plus':
268  $GLOBALS[$key] += $val;
269  break;
270  case 'array_merge':
271  $GLOBALS[$key] = array_merge( $val, $GLOBALS[$key] );
272  break;
273  default:
274  throw new UnexpectedValueException( "Unknown merge strategy '$mergeStrategy'" );
275  }
276  }
277 
278  foreach ( $info['defines'] as $name => $val ) {
279  define( $name, $val );
280  }
281  foreach ( $info['autoloaderPaths'] as $path ) {
282  require_once $path;
283  }
284 
285  $this->loaded += $info['credits'];
286  if ( $info['attributes'] ) {
287  if ( !$this->attributes ) {
288  $this->attributes = $info['attributes'];
289  } else {
290  $this->attributes = array_merge_recursive( $this->attributes, $info['attributes'] );
291  }
292  }
293 
294  foreach ( $info['callbacks'] as $name => $cb ) {
295  call_user_func( $cb, $info['credits'][$name] );
296  }
297  }
298 
307  public function load( $path ) {
308  $this->loadFromQueue(); // First clear the queue
309  $this->queue( $path );
310  $this->loadFromQueue();
311  }
312 
318  public function isLoaded( $name ) {
319  return isset( $this->loaded[$name] );
320  }
321 
326  public function getAttribute( $name ) {
327  if ( isset( $this->attributes[$name] ) ) {
328  return $this->attributes[$name];
329  } else {
330  return [];
331  }
332  }
333 
339  public function getAllThings() {
340  return $this->loaded;
341  }
342 
349  protected function markLoaded( $name, array $credits ) {
350  $this->loaded[$name] = $credits;
351  }
352 
360  protected function processAutoLoader( $dir, array $info ) {
361  if ( isset( $info['AutoloadClasses'] ) ) {
362  // Make paths absolute, relative to the JSON file
363  return array_map( function( $file ) use ( $dir ) {
364  return "$dir/$file";
365  }, $info['AutoloadClasses'] );
366  } else {
367  return [];
368  }
369  }
370 }
static ExtensionRegistry $instance
const MANIFEST_VERSION
Version of the highest supported manifest version.
the array() calling protocol came about after MediaWiki 1.4rc1.
$wgVersion
MediaWiki version number.
processAutoLoader($dir, array $info)
Register classes with the autoloader.
if(count($args)==0) $dir
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
div flags Integer display flags(NO_ACTION_LINK, NO_EXTRA_USER_LINKS) 'LogException'returning false will NOT prevent logging $e
Definition: hooks.txt:2106
exportExtractedData(array $info)
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency MediaWikiServices
Definition: injection.txt:23
when a variable name is used in a it is silently declared as a new local masking the global
Definition: design.txt:93
getAllThings()
Get information about all things.
array $loaded
Array of loaded things, keyed by name, values are credits information.
const MERGE_STRATEGY
Special key that defines the merge strategy.
isLoaded($name)
Whether a thing has been loaded.
you have access to all of the normal MediaWiki so you can get a DB use the cache
Definition: maintenance.txt:52
clearQueue()
Clear the current load queue.
$GLOBALS['IP']
const CACHE_VERSION
Bump whenever the registration cache needs resetting.
array $attributes
Items in the JSON file that aren't being set as globals.
int bool $wgExtensionInfoMTime
When loading extensions through the extension registration system, this can be used to invalidate the...
const MEDIAWIKI_CORE
"requires" key that applies to MediaWiki core/$wgVersion
A BagOStuff object with no objects in it.
const OLDEST_MANIFEST_VERSION
Version of the oldest supported manifest version.
This document is intended to provide useful advice for parties seeking to redistribute MediaWiki to end users It s targeted particularly at maintainers for Linux since it s been observed that distribution packages of MediaWiki often break We ve consistently had to recommend that users seeking support use official tarballs instead of their distribution s and this often solves whatever problem the user is having It would be nice if this could such as
Definition: distributors.txt:9
markLoaded($name, array $credits)
Mark a thing as loaded.
ExtensionRegistry class.
readFromQueue(array $queue)
Process a queue of extensions and return their extracted data.
array $queued
List of paths that should be loaded.
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
Definition: injection.txt:35
load($path)
Loads and processes the given JSON file without delay.
wfMemcKey()
Make a cache key for the local wiki.
wfArrayPlus2d(array $baseArray, array $newValues)
Merges two (possibly) 2 dimensional arrays into the target array ($baseArray).
getQueue()
Get the current load queue.
Allows to change the fields on the form that will be generated $name
Definition: hooks.txt:304