summaryrefslogtreecommitdiff
path: root/includes/filerepo/RepoGroup.php
blob: d487590884959603e9d0d4bd22f4970baf795470 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
<?php
/**
 * Prioritized list of file repositories
 *
 * @file
 * @ingroup FileRepo
 */

/**
 * @defgroup FileRepo FileRepo
 */

/**
 * Prioritized list of file repositories
 *
 * @ingroup FileRepo
 */
class RepoGroup {

	/**
	 * @var LocalRepo
	 */
	var $localRepo;

	var $foreignRepos, $reposInitialised = false;
	var $localInfo, $foreignInfo;
	var $cache;

	/**
	 * @var RepoGroup
	 */
	protected static $instance;
	const MAX_CACHE_SIZE = 1000;

	/**
	 * Get a RepoGroup instance. At present only one instance of RepoGroup is
	 * needed in a MediaWiki invocation, this may change in the future.
	 * @return RepoGroup
	 */
	static function singleton() {
		if ( self::$instance ) {
			return self::$instance;
		}
		global $wgLocalFileRepo, $wgForeignFileRepos;
		self::$instance = new RepoGroup( $wgLocalFileRepo, $wgForeignFileRepos );
		return self::$instance;
	}

	/**
	 * Destroy the singleton instance, so that a new one will be created next
	 * time singleton() is called.
	 */
	static function destroySingleton() {
		self::$instance = null;
	}

	/**
	 * Set the singleton instance to a given object
	 *
	 * @param $instance RepoGroup
	 */
	static function setSingleton( $instance ) {
		self::$instance = $instance;
	}

	/**
	 * Construct a group of file repositories.
	 *
	 * @param $localInfo Associative array for local repo's info
	 * @param $foreignInfo Array of repository info arrays.
	 *     Each info array is an associative array with the 'class' member
	 *     giving the class name. The entire array is passed to the repository
	 *     constructor as the first parameter.
	 */
	function __construct( $localInfo, $foreignInfo ) {
		$this->localInfo = $localInfo;
		$this->foreignInfo = $foreignInfo;
		$this->cache = array();
	}

	/**
	 * Search repositories for an image.
	 * You can also use wfFindFile() to do this.
	 *
	 * @param $title Title|string Title object or string
	 * @param $options array Associative array of options:
	 *     time:           requested time for an archived image, or false for the
	 *                     current version. An image object will be returned which was
	 *                     created at the specified time.
	 *
	 *     ignoreRedirect: If true, do not follow file redirects
	 *
	 *     private:        If true, return restricted (deleted) files if the current
	 *                     user is allowed to view them. Otherwise, such files will not
	 *                     be found.
	 *
	 *     bypassCache:    If true, do not use the process-local cache of File objects
	 * @return File object or false if it is not found
	 */
	function findFile( $title, $options = array() ) {
		if ( !is_array( $options ) ) {
			// MW 1.15 compat
			$options = array( 'time' => $options );
		}
		if ( !$this->reposInitialised ) {
			$this->initialiseRepos();
		}
		if ( !($title instanceof Title) ) {
			$title = Title::makeTitleSafe( NS_FILE, $title );
			if ( !is_object( $title ) ) {
				return false;
			}
		}

		if ( $title->getNamespace() != NS_MEDIA && $title->getNamespace() != NS_FILE ) {
			throw new MWException( __METHOD__ . ' received an Title object with incorrect namespace' );
		}

		# Check the cache
		if ( empty( $options['ignoreRedirect'] )
			&& empty( $options['private'] )
			&& empty( $options['bypassCache'] )
			&& $title->getNamespace() == NS_FILE )
		{
			$useCache = true;
			$time = isset( $options['time'] ) ? $options['time'] : '';
			$dbkey = $title->getDBkey();
			if ( isset( $this->cache[$dbkey][$time] ) ) {
				wfDebug( __METHOD__.": got File:$dbkey from process cache\n" );
				# Move it to the end of the list so that we can delete the LRU entry later
				$tmp = $this->cache[$dbkey];
				unset( $this->cache[$dbkey] );
				$this->cache[$dbkey] = $tmp;
				# Return the entry
				return $this->cache[$dbkey][$time];
			} else {
				# Add a negative cache entry, may be overridden
				$this->trimCache();
				$this->cache[$dbkey][$time] = false;
				$cacheEntry =& $this->cache[$dbkey][$time];
			}
		} else {
			$useCache = false;
		}

		# Check the local repo
		$image = $this->localRepo->findFile( $title, $options );
		if ( $image ) {
			if ( $useCache ) {
				$cacheEntry = $image;
			}
			return $image;
		}

		# Check the foreign repos
		foreach ( $this->foreignRepos as $repo ) {
			$image = $repo->findFile( $title, $options );
			if ( $image ) {
				if ( $useCache ) {
					$cacheEntry = $image;
				}
				return $image;
			}
		}
		# Not found, do not override negative cache
		return false;
	}

	function findFiles( $inputItems ) {
		if ( !$this->reposInitialised ) {
			$this->initialiseRepos();
		}

		$items = array();
		foreach ( $inputItems as $item ) {
			if ( !is_array( $item ) ) {
				$item = array( 'title' => $item );
			}
			if ( !( $item['title'] instanceof Title ) )
				$item['title'] = Title::makeTitleSafe( NS_FILE, $item['title'] );
			if ( $item['title'] )
				$items[$item['title']->getDBkey()] = $item;
		}

		$images = $this->localRepo->findFiles( $items );

		foreach ( $this->foreignRepos as $repo ) {
			// Remove found files from $items
			foreach ( $images as $name => $image ) {
				unset( $items[$name] );
			}

			$images = array_merge( $images, $repo->findFiles( $items ) );
		}
		return $images;
	}

	/**
	 * Interface for FileRepo::checkRedirect()
	 */
	function checkRedirect( $title ) {
		if ( !$this->reposInitialised ) {
			$this->initialiseRepos();
		}

		$redir = $this->localRepo->checkRedirect( $title );
		if( $redir ) {
			return $redir;
		}
		foreach ( $this->foreignRepos as $repo ) {
			$redir = $repo->checkRedirect( $title );
			if ( $redir ) {
				return $redir;
			}
		}
		return false;
	}

	/**
	 * Find an instance of the file with this key, created at the specified time
	 * Returns false if the file does not exist.
	 *
	 * @param $hash String base 36 SHA-1 hash
	 * @param $options Option array, same as findFile()
	 * @return File object or false if it is not found
	 */
	function findFileFromKey( $hash, $options = array() ) {
		if ( !$this->reposInitialised ) {
			$this->initialiseRepos();
		}

		$file = $this->localRepo->findFileFromKey( $hash, $options );
		if ( !$file ) {
			foreach ( $this->foreignRepos as $repo ) {
				$file = $repo->findFileFromKey( $hash, $options );
				if ( $file ) break;
			}
		}
		return $file;
	}

	/**
	 * Find all instances of files with this key
	 *
	 * @param $hash String base 36 SHA-1 hash
	 * @return Array of File objects
	 */
	function findBySha1( $hash ) {
		if ( !$this->reposInitialised ) {
			$this->initialiseRepos();
		}

		$result = $this->localRepo->findBySha1( $hash );
		foreach ( $this->foreignRepos as $repo ) {
			$result = array_merge( $result, $repo->findBySha1( $hash ) );
		}
		return $result;
	}

	/**
	 * Get the repo instance with a given key.
	 */
	function getRepo( $index ) {
		if ( !$this->reposInitialised ) {
			$this->initialiseRepos();
		}
		if ( $index === 'local' ) {
			return $this->localRepo;
		} elseif ( isset( $this->foreignRepos[$index] ) ) {
			return $this->foreignRepos[$index];
		} else {
			return false;
		}
	}
	/**
	 * Get the repo instance by its name
	 */
	function getRepoByName( $name ) {
		if ( !$this->reposInitialised ) {
			$this->initialiseRepos();
		}
		foreach ( $this->foreignRepos as $repo ) {
			if ( $repo->name == $name)
				return $repo;
		}
		return false;
	}

	/**
	 * Get the local repository, i.e. the one corresponding to the local image
	 * table. Files are typically uploaded to the local repository.
	 *
	 * @return LocalRepo
	 */
	function getLocalRepo() {
		return $this->getRepo( 'local' );
	}

	/**
	 * Call a function for each foreign repo, with the repo object as the
	 * first parameter.
	 *
	 * @param $callback Callback: the function to call
	 * @param $params Array: optional additional parameters to pass to the function
	 */
	function forEachForeignRepo( $callback, $params = array() ) {
		foreach( $this->foreignRepos as $repo ) {
			$args = array_merge( array( $repo ), $params );
			if( call_user_func_array( $callback, $args ) ) {
				return true;
			}
		}
		return false;
	}

	/**
	 * Does the installation have any foreign repos set up?
	 * @return Boolean
	 */
	function hasForeignRepos() {
		return (bool)$this->foreignRepos;
	}

	/**
	 * Initialise the $repos array
	 */
	function initialiseRepos() {
		if ( $this->reposInitialised ) {
			return;
		}
		$this->reposInitialised = true;

		$this->localRepo = $this->newRepo( $this->localInfo );
		$this->foreignRepos = array();
		foreach ( $this->foreignInfo as $key => $info ) {
			$this->foreignRepos[$key] = $this->newRepo( $info );
		}
	}

	/**
	 * Create a repo class based on an info structure
	 */
	protected function newRepo( $info ) {
		$class = $info['class'];
		return new $class( $info );
	}

	/**
	 * Split a virtual URL into repo, zone and rel parts
	 * @return an array containing repo, zone and rel
	 */
	function splitVirtualUrl( $url ) {
		if ( substr( $url, 0, 9 ) != 'mwrepo://' ) {
			throw new MWException( __METHOD__.': unknown protocol' );
		}

		$bits = explode( '/', substr( $url, 9 ), 3 );
		if ( count( $bits ) != 3 ) {
			throw new MWException( __METHOD__.": invalid mwrepo URL: $url" );
		}
		return $bits;
	}

	function getFileProps( $fileName ) {
		if ( FileRepo::isVirtualUrl( $fileName ) ) {
			list( $repoName, /* $zone */, /* $rel */ ) = $this->splitVirtualUrl( $fileName );
			if ( $repoName === '' ) {
				$repoName = 'local';
			}
			$repo = $this->getRepo( $repoName );
			return $repo->getFileProps( $fileName );
		} else {
			return File::getPropsFromPath( $fileName );
		}
	}

	/**
	 * Limit cache memory
	 */
	function trimCache() {
		while ( count( $this->cache ) >= self::MAX_CACHE_SIZE ) {
			reset( $this->cache );
			$key = key( $this->cache );
			wfDebug( __METHOD__.": evicting $key\n" );
			unset( $this->cache[$key] );
		}
	}
}