1
|
|
|
<?php |
2
|
|
|
/** |
3
|
|
|
* Functions to get cache objects. |
4
|
|
|
* |
5
|
|
|
* This program is free software; you can redistribute it and/or modify |
6
|
|
|
* it under the terms of the GNU General Public License as published by |
7
|
|
|
* the Free Software Foundation; either version 2 of the License, or |
8
|
|
|
* (at your option) any later version. |
9
|
|
|
* |
10
|
|
|
* This program is distributed in the hope that it will be useful, |
11
|
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
12
|
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
13
|
|
|
* GNU General Public License for more details. |
14
|
|
|
* |
15
|
|
|
* You should have received a copy of the GNU General Public License along |
16
|
|
|
* with this program; if not, write to the Free Software Foundation, Inc., |
17
|
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. |
18
|
|
|
* http://www.gnu.org/copyleft/gpl.html |
19
|
|
|
* |
20
|
|
|
* @file |
21
|
|
|
* @ingroup Cache |
22
|
|
|
*/ |
23
|
|
|
|
24
|
|
|
use MediaWiki\Logger\LoggerFactory; |
25
|
|
|
use MediaWiki\MediaWikiServices; |
26
|
|
|
|
27
|
|
|
/** |
28
|
|
|
* Functions to get cache objects |
29
|
|
|
* |
30
|
|
|
* The word "cache" has two main dictionary meanings, and both |
31
|
|
|
* are used in this factory class. They are: |
32
|
|
|
* |
33
|
|
|
* - a) Cache (the computer science definition). |
34
|
|
|
* A place to store copies or computations on existing data for |
35
|
|
|
* higher access speeds. |
36
|
|
|
* - b) Storage. |
37
|
|
|
* A place to store lightweight data that is not canonically |
38
|
|
|
* stored anywhere else (e.g. a "hoard" of objects). |
39
|
|
|
* |
40
|
|
|
* The former should always use strongly consistent stores, so callers don't |
41
|
|
|
* have to deal with stale reads. The latter may be eventually consistent, but |
42
|
|
|
* callers can use BagOStuff:READ_LATEST to see the latest available data. |
43
|
|
|
* |
44
|
|
|
* Primary entry points: |
45
|
|
|
* |
46
|
|
|
* - ObjectCache::getMainWANInstance() |
47
|
|
|
* Purpose: Memory cache. |
48
|
|
|
* Stored in the local data-center's main cache (keyspace different from local-cluster cache). |
49
|
|
|
* Delete events are broadcasted to other DCs main cache. See WANObjectCache for details. |
50
|
|
|
* |
51
|
|
|
* - ObjectCache::getLocalServerInstance( $fallbackType ) |
52
|
|
|
* Purpose: Memory cache for very hot keys. |
53
|
|
|
* Stored only on the individual web server (typically APC or APCu for web requests, |
54
|
|
|
* and EmptyBagOStuff in CLI mode). |
55
|
|
|
* Not replicated to the other servers. |
56
|
|
|
* |
57
|
|
|
* - ObjectCache::getLocalClusterInstance() |
58
|
|
|
* Purpose: Memory storage for per-cluster coordination and tracking. |
59
|
|
|
* A typical use case would be a rate limit counter or cache regeneration mutex. |
60
|
|
|
* Stored centrally within the local data-center. Not replicated to other DCs. |
61
|
|
|
* Configured by $wgMainCacheType. |
62
|
|
|
* |
63
|
|
|
* - ObjectCache::getMainStashInstance() |
64
|
|
|
* Purpose: Ephemeral global storage. |
65
|
|
|
* Stored centrally within the primary data-center. |
66
|
|
|
* Changes are applied there first and replicated to other DCs (best-effort). |
67
|
|
|
* To retrieve the latest value (e.g. not from a replica DB), use BagOStuff::READ_LATEST. |
68
|
|
|
* This store may be subject to LRU style evictions. |
69
|
|
|
* |
70
|
|
|
* - ObjectCache::getInstance( $cacheType ) |
71
|
|
|
* Purpose: Special cases (like tiered memory/disk caches). |
72
|
|
|
* Get a specific cache type by key in $wgObjectCaches. |
73
|
|
|
* |
74
|
|
|
* All the above cache instances (BagOStuff and WANObjectCache) have their makeKey() |
75
|
|
|
* method scoped to the *current* wiki ID. Use makeGlobalKey() to avoid this scoping |
76
|
|
|
* when using keys that need to be shared amongst wikis. |
77
|
|
|
* |
78
|
|
|
* @ingroup Cache |
79
|
|
|
*/ |
80
|
|
|
class ObjectCache { |
81
|
|
|
/** @var BagOStuff[] Map of (id => BagOStuff) */ |
82
|
|
|
public static $instances = []; |
83
|
|
|
/** @var WANObjectCache[] Map of (id => WANObjectCache) */ |
84
|
|
|
public static $wanInstances = []; |
85
|
|
|
|
86
|
|
|
/** |
87
|
|
|
* Get a cached instance of the specified type of cache object. |
88
|
|
|
* |
89
|
|
|
* @param string $id A key in $wgObjectCaches. |
90
|
|
|
* @return BagOStuff |
91
|
|
|
*/ |
92
|
|
|
public static function getInstance( $id ) { |
93
|
|
|
if ( !isset( self::$instances[$id] ) ) { |
94
|
|
|
self::$instances[$id] = self::newFromId( $id ); |
95
|
|
|
} |
96
|
|
|
|
97
|
|
|
return self::$instances[$id]; |
98
|
|
|
} |
99
|
|
|
|
100
|
|
|
/** |
101
|
|
|
* Get a cached instance of the specified type of WAN cache object. |
102
|
|
|
* |
103
|
|
|
* @since 1.26 |
104
|
|
|
* @param string $id A key in $wgWANObjectCaches. |
105
|
|
|
* @return WANObjectCache |
106
|
|
|
*/ |
107
|
|
|
public static function getWANInstance( $id ) { |
108
|
|
|
if ( !isset( self::$wanInstances[$id] ) ) { |
109
|
|
|
self::$wanInstances[$id] = self::newWANCacheFromId( $id ); |
110
|
|
|
} |
111
|
|
|
|
112
|
|
|
return self::$wanInstances[$id]; |
113
|
|
|
} |
114
|
|
|
|
115
|
|
|
/** |
116
|
|
|
* Create a new cache object of the specified type. |
117
|
|
|
* |
118
|
|
|
* @param string $id A key in $wgObjectCaches. |
119
|
|
|
* @return BagOStuff |
120
|
|
|
* @throws InvalidArgumentException |
121
|
|
|
*/ |
122
|
|
|
public static function newFromId( $id ) { |
123
|
|
|
global $wgObjectCaches; |
124
|
|
|
|
125
|
|
|
if ( !isset( $wgObjectCaches[$id] ) ) { |
126
|
|
|
// Always recognize these ones |
127
|
|
|
if ( $id === CACHE_NONE ) { |
|
|
|
|
128
|
|
|
return new EmptyBagOStuff(); |
129
|
|
|
} elseif ( $id === 'hash' ) { |
130
|
|
|
return new HashBagOStuff(); |
131
|
|
|
} |
132
|
|
|
|
133
|
|
|
throw new InvalidArgumentException( "Invalid object cache type \"$id\" requested. " . |
134
|
|
|
"It is not present in \$wgObjectCaches." ); |
135
|
|
|
} |
136
|
|
|
|
137
|
|
|
return self::newFromParams( $wgObjectCaches[$id] ); |
138
|
|
|
} |
139
|
|
|
|
140
|
|
|
/** |
141
|
|
|
* Get the default keyspace for this wiki. |
142
|
|
|
* |
143
|
|
|
* This is either the value of the `CachePrefix` configuration variable, |
144
|
|
|
* or (if the former is unset) the `DBname` configuration variable, with |
145
|
|
|
* `DBprefix` (if defined). |
146
|
|
|
* |
147
|
|
|
* @return string |
148
|
|
|
*/ |
149
|
|
|
public static function getDefaultKeyspace() { |
150
|
|
|
global $wgCachePrefix; |
151
|
|
|
|
152
|
|
|
$keyspace = $wgCachePrefix; |
153
|
|
|
if ( is_string( $keyspace ) && $keyspace !== '' ) { |
154
|
|
|
return $keyspace; |
155
|
|
|
} |
156
|
|
|
|
157
|
|
|
return wfWikiID(); |
158
|
|
|
} |
159
|
|
|
|
160
|
|
|
/** |
161
|
|
|
* Create a new cache object from parameters. |
162
|
|
|
* |
163
|
|
|
* @param array $params Must have 'factory' or 'class' property. |
164
|
|
|
* - factory: Callback passed $params that returns BagOStuff. |
165
|
|
|
* - class: BagOStuff subclass constructed with $params. |
166
|
|
|
* - loggroup: Alias to set 'logger' key with LoggerFactory group. |
167
|
|
|
* - .. Other parameters passed to factory or class. |
168
|
|
|
* @return BagOStuff |
169
|
|
|
* @throws InvalidArgumentException |
170
|
|
|
*/ |
171
|
|
|
public static function newFromParams( $params ) { |
|
|
|
|
172
|
|
View Code Duplication |
if ( isset( $params['loggroup'] ) ) { |
173
|
|
|
$params['logger'] = LoggerFactory::getInstance( $params['loggroup'] ); |
174
|
|
|
} else { |
175
|
|
|
$params['logger'] = LoggerFactory::getInstance( 'objectcache' ); |
176
|
|
|
} |
177
|
|
|
if ( !isset( $params['keyspace'] ) ) { |
178
|
|
|
$params['keyspace'] = self::getDefaultKeyspace(); |
179
|
|
|
} |
180
|
|
|
if ( isset( $params['factory'] ) ) { |
181
|
|
|
return call_user_func( $params['factory'], $params ); |
182
|
|
|
} elseif ( isset( $params['class'] ) ) { |
183
|
|
|
$class = $params['class']; |
184
|
|
|
// Automatically set the 'async' update handler |
185
|
|
|
$params['asyncHandler'] = isset( $params['asyncHandler'] ) |
186
|
|
|
? $params['asyncHandler'] |
187
|
|
|
: 'DeferredUpdates::addCallableUpdate'; |
188
|
|
|
// Enable reportDupes by default |
189
|
|
|
$params['reportDupes'] = isset( $params['reportDupes'] ) |
190
|
|
|
? $params['reportDupes'] |
191
|
|
|
: true; |
192
|
|
|
// Do b/c logic for SqlBagOStuff |
193
|
|
|
if ( is_a( $class, SqlBagOStuff::class, true ) ) { |
194
|
|
|
if ( isset( $params['server'] ) && !isset( $params['servers'] ) ) { |
195
|
|
|
$params['servers'] = [ $params['server'] ]; |
196
|
|
|
unset( $params['server'] ); |
197
|
|
|
} |
198
|
|
|
// In the past it was not required to set 'dbDirectory' in $wgObjectCaches |
199
|
|
|
if ( isset( $params['servers'] ) ) { |
200
|
|
|
foreach ( $params['servers'] as &$server ) { |
201
|
|
|
if ( $server['type'] === 'sqlite' && !isset( $server['dbDirectory'] ) ) { |
202
|
|
|
$server['dbDirectory'] = MediaWikiServices::getInstance() |
203
|
|
|
->getMainConfig()->get( 'SQLiteDataDir' ); |
204
|
|
|
} |
205
|
|
|
} |
206
|
|
|
} |
207
|
|
|
} |
208
|
|
|
|
209
|
|
|
// Do b/c logic for MemcachedBagOStuff |
210
|
|
|
if ( is_subclass_of( $class, MemcachedBagOStuff::class ) ) { |
211
|
|
|
if ( !isset( $params['servers'] ) ) { |
212
|
|
|
$params['servers'] = $GLOBALS['wgMemCachedServers']; |
213
|
|
|
} |
214
|
|
|
if ( !isset( $params['debug'] ) ) { |
215
|
|
|
$params['debug'] = $GLOBALS['wgMemCachedDebug']; |
216
|
|
|
} |
217
|
|
|
if ( !isset( $params['persistent'] ) ) { |
218
|
|
|
$params['persistent'] = $GLOBALS['wgMemCachedPersistent']; |
219
|
|
|
} |
220
|
|
|
if ( !isset( $params['timeout'] ) ) { |
221
|
|
|
$params['timeout'] = $GLOBALS['wgMemCachedTimeout']; |
222
|
|
|
} |
223
|
|
|
} |
224
|
|
|
return new $class( $params ); |
225
|
|
|
} else { |
226
|
|
|
throw new InvalidArgumentException( "The definition of cache type \"" |
227
|
|
|
. print_r( $params, true ) . "\" lacks both " |
228
|
|
|
. "factory and class parameters." ); |
229
|
|
|
} |
230
|
|
|
} |
231
|
|
|
|
232
|
|
|
/** |
233
|
|
|
* Factory function for CACHE_ANYTHING (referenced from DefaultSettings.php) |
234
|
|
|
* |
235
|
|
|
* CACHE_ANYTHING means that stuff has to be cached, not caching is not an option. |
236
|
|
|
* If a caching method is configured for any of the main caches ($wgMainCacheType, |
237
|
|
|
* $wgMessageCacheType, $wgParserCacheType), then CACHE_ANYTHING will effectively |
238
|
|
|
* be an alias to the configured cache choice for that. |
239
|
|
|
* If no cache choice is configured (by default $wgMainCacheType is CACHE_NONE), |
240
|
|
|
* then CACHE_ANYTHING will forward to CACHE_DB. |
241
|
|
|
* |
242
|
|
|
* @param array $params |
243
|
|
|
* @return BagOStuff |
244
|
|
|
*/ |
245
|
|
|
public static function newAnything( $params ) { |
246
|
|
|
global $wgMainCacheType, $wgMessageCacheType, $wgParserCacheType; |
247
|
|
|
$candidates = [ $wgMainCacheType, $wgMessageCacheType, $wgParserCacheType ]; |
248
|
|
|
foreach ( $candidates as $candidate ) { |
249
|
|
|
if ( $candidate !== CACHE_NONE && $candidate !== CACHE_ANYTHING ) { |
250
|
|
|
return self::getInstance( $candidate ); |
251
|
|
|
} |
252
|
|
|
} |
253
|
|
|
|
254
|
|
|
if ( MediaWikiServices::getInstance()->isServiceDisabled( 'DBLoadBalancer' ) ) { |
255
|
|
|
// The LoadBalancer is disabled, probably because |
256
|
|
|
// MediaWikiServices::disableStorageBackend was called. |
257
|
|
|
$candidate = CACHE_NONE; |
258
|
|
|
} else { |
259
|
|
|
$candidate = CACHE_DB; |
260
|
|
|
} |
261
|
|
|
|
262
|
|
|
return self::getInstance( $candidate ); |
263
|
|
|
} |
264
|
|
|
|
265
|
|
|
/** |
266
|
|
|
* Factory function for CACHE_ACCEL (referenced from DefaultSettings.php) |
267
|
|
|
* |
268
|
|
|
* This will look for any APC or APCu style server-local cache. |
269
|
|
|
* A fallback cache can be specified if none is found. |
270
|
|
|
* |
271
|
|
|
* // Direct calls |
272
|
|
|
* ObjectCache::getLocalServerInstance( $fallbackType ); |
273
|
|
|
* |
274
|
|
|
* // From $wgObjectCaches via newFromParams() |
275
|
|
|
* ObjectCache::getLocalServerInstance( [ 'fallback' => $fallbackType ] ); |
276
|
|
|
* |
277
|
|
|
* @param int|string|array $fallback Fallback cache or parameter map with 'fallback' |
278
|
|
|
* @return BagOStuff |
279
|
|
|
* @throws InvalidArgumentException |
280
|
|
|
* @since 1.27 |
281
|
|
|
*/ |
282
|
|
|
public static function getLocalServerInstance( $fallback = CACHE_NONE ) { |
283
|
|
|
$cache = MediaWikiServices::getInstance()->getLocalServerObjectCache(); |
284
|
|
|
if ( $cache instanceof EmptyBagOStuff ) { |
285
|
|
|
if ( is_array( $fallback ) ) { |
286
|
|
|
$fallback = isset( $fallback['fallback'] ) ? $fallback['fallback'] : CACHE_NONE; |
287
|
|
|
} |
288
|
|
|
$cache = self::getInstance( $fallback ); |
289
|
|
|
} |
290
|
|
|
|
291
|
|
|
return $cache; |
292
|
|
|
} |
293
|
|
|
|
294
|
|
|
/** |
295
|
|
|
* Create a new cache object of the specified type. |
296
|
|
|
* |
297
|
|
|
* @since 1.26 |
298
|
|
|
* @param string $id A key in $wgWANObjectCaches. |
299
|
|
|
* @return WANObjectCache |
300
|
|
|
* @throws UnexpectedValueException |
301
|
|
|
*/ |
302
|
|
|
public static function newWANCacheFromId( $id ) { |
303
|
|
|
global $wgWANObjectCaches, $wgObjectCaches; |
304
|
|
|
|
305
|
|
|
if ( !isset( $wgWANObjectCaches[$id] ) ) { |
306
|
|
|
throw new UnexpectedValueException( |
307
|
|
|
"Cache type \"$id\" requested is not present in \$wgWANObjectCaches." ); |
308
|
|
|
} |
309
|
|
|
|
310
|
|
|
$params = $wgWANObjectCaches[$id]; |
311
|
|
|
if ( !isset( $wgObjectCaches[$params['cacheId']] ) ) { |
312
|
|
|
throw new UnexpectedValueException( |
313
|
|
|
"Cache type \"{$params['cacheId']}\" is not present in \$wgObjectCaches." ); |
314
|
|
|
} |
315
|
|
|
$params['store'] = $wgObjectCaches[$params['cacheId']]; |
316
|
|
|
|
317
|
|
|
return self::newWANCacheFromParams( $params ); |
318
|
|
|
} |
319
|
|
|
|
320
|
|
|
/** |
321
|
|
|
* Create a new cache object of the specified type. |
322
|
|
|
* |
323
|
|
|
* @since 1.28 |
324
|
|
|
* @param array $params |
325
|
|
|
* @return WANObjectCache |
326
|
|
|
* @throws UnexpectedValueException |
327
|
|
|
*/ |
328
|
|
|
public static function newWANCacheFromParams( array $params ) { |
329
|
|
|
foreach ( $params['channels'] as $action => $channel ) { |
330
|
|
|
$params['relayers'][$action] = MediaWikiServices::getInstance()->getEventRelayerGroup() |
331
|
|
|
->getRelayer( $channel ); |
332
|
|
|
$params['channels'][$action] = $channel; |
333
|
|
|
} |
334
|
|
|
$params['cache'] = self::newFromParams( $params['store'] ); |
335
|
|
View Code Duplication |
if ( isset( $params['loggroup'] ) ) { |
336
|
|
|
$params['logger'] = LoggerFactory::getInstance( $params['loggroup'] ); |
337
|
|
|
} else { |
338
|
|
|
$params['logger'] = LoggerFactory::getInstance( 'objectcache' ); |
339
|
|
|
} |
340
|
|
|
$class = $params['class']; |
341
|
|
|
|
342
|
|
|
return new $class( $params ); |
343
|
|
|
} |
344
|
|
|
|
345
|
|
|
/** |
346
|
|
|
* Get the main cluster-local cache object. |
347
|
|
|
* |
348
|
|
|
* @since 1.27 |
349
|
|
|
* @return BagOStuff |
350
|
|
|
*/ |
351
|
|
|
public static function getLocalClusterInstance() { |
352
|
|
|
global $wgMainCacheType; |
353
|
|
|
|
354
|
|
|
return self::getInstance( $wgMainCacheType ); |
355
|
|
|
} |
356
|
|
|
|
357
|
|
|
/** |
358
|
|
|
* Get the main WAN cache object. |
359
|
|
|
* |
360
|
|
|
* @since 1.26 |
361
|
|
|
* @return WANObjectCache |
362
|
|
|
* @deprecated Since 1.28 Use MediaWikiServices::getMainWANCache() |
363
|
|
|
*/ |
364
|
|
|
public static function getMainWANInstance() { |
365
|
|
|
return MediaWikiServices::getInstance()->getMainWANObjectCache(); |
366
|
|
|
} |
367
|
|
|
|
368
|
|
|
/** |
369
|
|
|
* Get the cache object for the main stash. |
370
|
|
|
* |
371
|
|
|
* Stash objects are BagOStuff instances suitable for storing light |
372
|
|
|
* weight data that is not canonically stored elsewhere (such as RDBMS). |
373
|
|
|
* Stashes should be configured to propagate changes to all data-centers. |
374
|
|
|
* |
375
|
|
|
* Callers should be prepared for: |
376
|
|
|
* - a) Writes to be slower in non-"primary" (e.g. HTTP GET/HEAD only) DCs |
377
|
|
|
* - b) Reads to be eventually consistent, e.g. for get()/getMulti() |
378
|
|
|
* In general, this means avoiding updates on idempotent HTTP requests and |
379
|
|
|
* avoiding an assumption of perfect serializability (or accepting anomalies). |
380
|
|
|
* Reads may be eventually consistent or data might rollback as nodes flap. |
381
|
|
|
* Callers can use BagOStuff:READ_LATEST to see the latest available data. |
382
|
|
|
* |
383
|
|
|
* @return BagOStuff |
384
|
|
|
* @since 1.26 |
385
|
|
|
* @deprecated Since 1.28 Use MediaWikiServices::getMainObjectStash |
386
|
|
|
*/ |
387
|
|
|
public static function getMainStashInstance() { |
388
|
|
|
return MediaWikiServices::getInstance()->getMainObjectStash(); |
389
|
|
|
} |
390
|
|
|
|
391
|
|
|
/** |
392
|
|
|
* Clear all the cached instances. |
393
|
|
|
*/ |
394
|
|
|
public static function clear() { |
395
|
|
|
self::$instances = []; |
396
|
|
|
self::$wanInstances = []; |
397
|
|
|
} |
398
|
|
|
} |
399
|
|
|
|