LinkCache::isCacheable() - Code Metrics - Inspection of "Daily Inspection: Merge "API: Fix query+authmanage..." - wikimedia/mediawiki - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Branch — master (fc4983)

unknown

created 2016-09-07 17:38 UTC

LinkCache::isCacheable() A

↳ Parent: LinkCache

Complexity

Conditions	2
Paths	2

Size

Total Lines	3
Code Lines	2

Duplication

Lines	0
Ratio	0 %

Importance

Changes	1
Bugs	0	Features	0

Metric	Value
cc	2
eloc	2
nc	2
nop	1
dl	0
loc	3
rs	10
c	1
b	0
f	0

<?php
/**
 * Page existence cache.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup Cache
 */
use MediaWiki\Linker\LinkTarget;
use MediaWiki\MediaWikiServices;

/**
 * Cache for article titles (prefixed DB keys) and ids linked from one source
 *
 * @ingroup Cache
 */
class LinkCache {
	/** @var HashBagOStuff */
	private $mGoodLinks;
	/** @var HashBagOStuff */
	private $mBadLinks;
	/** @var WANObjectCache */
	private $wanCache;

	/** @var bool */
	private $mForUpdate = false;

	/** @var TitleFormatter */
	private $titleFormatter;

	/**
	 * How many Titles to store. There are two caches, so the amount actually
	 * stored in memory can be up to twice this.
	 */
	const MAX_SIZE = 10000;

	public function __construct( TitleFormatter $titleFormatter, WANObjectCache $cache ) {
		$this->mGoodLinks = new HashBagOStuff( [ 'maxKeys' => self::MAX_SIZE ] );
		$this->mBadLinks = new HashBagOStuff( [ 'maxKeys' => self::MAX_SIZE ] );
		$this->wanCache = $cache;
		$this->titleFormatter = $titleFormatter;
	}

	/**
	 * Get an instance of this class.
	 *
	 * @return LinkCache
	 * @deprecated since 1.28, use MediaWikiServices instead
	 */
	public static function singleton() {
		return MediaWikiServices::getInstance()->getLinkCache();
	}

	/**
	 * General accessor to get/set whether the master DB should be used
	 *
	 * This used to also set the FOR UPDATE option (locking the rows read
	 * in order to avoid link table inconsistency), which was later removed
	 * for performance on wikis with a high edit rate.
	 *
	 * @param bool $update
	 * @return bool
	 */
	public function forUpdate( $update = null ) {
		return wfSetVar( $this->mForUpdate, $update );
	}

	/**
	 * @param string $title Prefixed DB key
	 * @return int Page ID or zero
	 */
	public function getGoodLinkID( $title ) {
		$info = $this->mGoodLinks->get( $title );
		if ( !$info ) {
			return 0;
		}
		return $info['id'];
	}

	/**
	 * Get a field of a title object from cache.
	 * If this link is not a cached good title, it will return NULL.
	 * @param LinkTarget $target
	 * @param string $field ('length','redirect','revision','model')
	 * @return string|int|null
	 */
	public function getGoodLinkFieldObj( LinkTarget $target, $field ) {
		$dbkey = $this->titleFormatter->getPrefixedDBkey( $target );
		$info = $this->mGoodLinks->get( $dbkey );
		if ( !$info ) {
			return null;
		}
		return $info[$field];
	}

	/**
	 * @param string $title Prefixed DB key
	 * @return bool
	 */
	public function isBadLink( $title ) {
		// Use get() to ensure it records as used for LRU.
		return $this->mBadLinks->get( $title ) !== false;
	}

	/**
	 * Add a link for the title to the link cache
	 *
	 * @param int $id Page's ID
	 * @param LinkTarget $target
	 * @param int $len Text's length
	 * @param int $redir Whether the page is a redirect
	 * @param int $revision Latest revision's ID
	 * @param string|null $model Latest revision's content model ID
	 * @param string|null $lang Language code of the page, if not the content language
	 */
	public function addGoodLinkObj( $id, LinkTarget $target, $len = -1, $redir = null,
		$revision = 0, $model = null, $lang = null
	) {
		$dbkey = $this->titleFormatter->getPrefixedDBkey( $target );
		$this->mGoodLinks->set( $dbkey, [
			'id' => (int)$id,
			'length' => (int)$len,
			'redirect' => (int)$redir,
			'revision' => (int)$revision,
			'model' => $model ? (string)$model : null,
			'lang' => $lang ? (string)$lang : null,
		] );
	}

	/**
	 * Same as above with better interface.
	 * @since 1.19
	 * @param LinkTarget $target
	 * @param stdClass $row Object which has the fields page_id, page_is_redirect,
	 *  page_latest and page_content_model
	 */
	public function addGoodLinkObjFromRow( LinkTarget $target, $row ) {
		$dbkey = $this->titleFormatter->getPrefixedDBkey( $target );
		$this->mGoodLinks->set( $dbkey, [
			'id' => intval( $row->page_id ),
			'length' => intval( $row->page_len ),
			'redirect' => intval( $row->page_is_redirect ),
			'revision' => intval( $row->page_latest ),
			'model' => !empty( $row->page_content_model ) ? strval( $row->page_content_model ) : null,
			'lang' => !empty( $row->page_lang ) ? strval( $row->page_lang ) : null,
		] );
	}

	/**
	 * @param LinkTarget $target
	 */
	public function addBadLinkObj( LinkTarget $target ) {
		$dbkey = $this->titleFormatter->getPrefixedDBkey( $target );
		if ( !$this->isBadLink( $dbkey ) ) {
			$this->mBadLinks->set( $dbkey, 1 );
		}
	}

	/**
	 * @param string $title Prefixed DB key
	 */
	public function clearBadLink( $title ) {
		$this->mBadLinks->delete( $title );
	}

	/**
	 * @param LinkTarget $target
	 */
	public function clearLink( LinkTarget $target ) {
		$dbkey = $this->titleFormatter->getPrefixedDBkey( $target );
		$this->mBadLinks->delete( $dbkey );
		$this->mGoodLinks->delete( $dbkey );
	}

	/**
	 * Add a title to the link cache, return the page_id or zero if non-existent
	 *
	 * @deprecated since 1.27, unused
	 * @param string $title Prefixed DB key
	 * @return int Page ID or zero
	 */
	public function addLink( $title ) {
		$nt = Title::newFromDBkey( $title );
		if ( !$nt ) {
			return 0;
		}
		return $this->addLinkObj( $nt );
	}

	/**
	 * Fields that LinkCache needs to select
	 *
	 * @since 1.28
	 * @return array
	 */
	public static function getSelectFields() {
		global $wgContentHandlerUseDB, $wgPageLanguageUseDB;

		$fields = [ 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ];
		if ( $wgContentHandlerUseDB ) {
			$fields[] = 'page_content_model';
		}
		if ( $wgPageLanguageUseDB ) {
			$fields[] = 'page_lang';
		}

		return $fields;
	}

	/**
	 * Add a title to the link cache, return the page_id or zero if non-existent
	 *
	 * @param LinkTarget $nt LinkTarget object to add
	 * @return int Page ID or zero
	 */
	public function addLinkObj( LinkTarget $nt ) {
		$key = $this->titleFormatter->getPrefixedDBkey( $nt );
		if ( $this->isBadLink( $key ) || $nt->isExternal()
			|| $nt->inNamespace( NS_SPECIAL )
		) {
			return 0;
		}
		$id = $this->getGoodLinkID( $key );
		if ( $id != 0 ) {
			return $id;
		}

		if ( $key === '' ) {
			return 0;
		}

		// Cache template/file pages as they are less often viewed but heavily used
		if ( $this->mForUpdate ) {
			$row = $this->fetchPageRow( wfGetDB( DB_MASTER ), $nt );
		} elseif ( $this->isCacheable( $nt ) ) {
			// These pages are often transcluded heavily, so cache them
			$cache = $this->wanCache;
			$row = $cache->getWithSetCallback(
				$cache->makeKey( 'page', $nt->getNamespace(), sha1( $nt->getDBkey() ) ),
				$cache::TTL_DAY,
				function ( $curValue, &$ttl, array &$setOpts ) use ( $cache, $nt ) {
					$dbr = wfGetDB( DB_REPLICA );
					$setOpts += Database::getCacheSetOptions( $dbr );

					$row = $this->fetchPageRow( $dbr, $nt );
					$mtime = $row ? wfTimestamp( TS_UNIX, $row->page_touched ) : false;
					$ttl = $cache->adaptiveTTL( $mtime, $ttl );

					return $row;
				}
			);
		} else {
			$row = $this->fetchPageRow( wfGetDB( DB_REPLICA ), $nt );
		}

		if ( $row ) {
			$this->addGoodLinkObjFromRow( $nt, $row );
			$id = intval( $row->page_id );
		} else {
			$this->addBadLinkObj( $nt );
			$id = 0;
		}

		return $id;
	}

	private function isCacheable( LinkTarget $title ) {
		return ( $title->inNamespace( NS_TEMPLATE ) || $title->inNamespace( NS_FILE ) );
	}

	private function fetchPageRow( IDatabase $db, LinkTarget $nt ) {
		$fields = self::getSelectFields();
		if ( $this->isCacheable( $nt ) ) {
			$fields[] = 'page_touched';
		}

		return $db->selectRow(
			'page',
			$fields,
			[ 'page_namespace' => $nt->getNamespace(), 'page_title' => $nt->getDBkey() ],
			__METHOD__
		);
	}

	/**
	 * Purge the link cache for a title
	 *
	 * @param LinkTarget $title
	 * @since 1.28
	 */
	public function invalidateTitle( LinkTarget $title ) {
		if ( $this->isCacheable( $title ) ) {
			$cache = ObjectCache::getMainWANInstance();
			$cache->delete(
				$cache->makeKey( 'page', $title->getNamespace(), sha1( $title->getDBkey() ) )
			);
		}
	}

	/**
	 * Clears cache
	 */
	public function clear() {
		$this->mGoodLinks->clear();
		$this->mBadLinks->clear();
	}
}


1		<?php
2		/**
3		* Page existence cache.
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		use MediaWiki\Linker\LinkTarget;
24		use MediaWiki\MediaWikiServices;
25
26		/**
27		* Cache for article titles (prefixed DB keys) and ids linked from one source
28		*
29		* @ingroup Cache
30		*/
31		class LinkCache {
32		/** @var HashBagOStuff */
33		private $mGoodLinks;
34		/** @var HashBagOStuff */
35		private $mBadLinks;
36		/** @var WANObjectCache */
37		private $wanCache;
38
39		/** @var bool */
40		private $mForUpdate = false;
41
42		/** @var TitleFormatter */
43		private $titleFormatter;
44
45		/**
46		* How many Titles to store. There are two caches, so the amount actually
47		* stored in memory can be up to twice this.
48		*/
49		const MAX_SIZE = 10000;
50
51		public function __construct( TitleFormatter $titleFormatter, WANObjectCache $cache ) {
52		$this->mGoodLinks = new HashBagOStuff( [ 'maxKeys' => self::MAX_SIZE ] );
53		$this->mBadLinks = new HashBagOStuff( [ 'maxKeys' => self::MAX_SIZE ] );
54		$this->wanCache = $cache;
55		$this->titleFormatter = $titleFormatter;
56		}
57
58		/**
59		* Get an instance of this class.
60		*
61		* @return LinkCache
62		* @deprecated since 1.28, use MediaWikiServices instead
63		*/
64		public static function singleton() {
65		return MediaWikiServices::getInstance()->getLinkCache();
66		}
67
68		/**
69		* General accessor to get/set whether the master DB should be used
70		*
71		* This used to also set the FOR UPDATE option (locking the rows read
72		* in order to avoid link table inconsistency), which was later removed
73		* for performance on wikis with a high edit rate.
74		*
75		* @param bool $update
76		* @return bool
77		*/
78		public function forUpdate( $update = null ) {
79		return wfSetVar( $this->mForUpdate, $update );
80		}
81
82		/**
83		* @param string $title Prefixed DB key
84		* @return int Page ID or zero
85		*/
86		public function getGoodLinkID( $title ) {
87		$info = $this->mGoodLinks->get( $title );
88		if ( !$info ) {
89		return 0;
90		}
91		return $info['id'];
92		}
93
94		/**
95		* Get a field of a title object from cache.
96		* If this link is not a cached good title, it will return NULL.
97		* @param LinkTarget $target
98		* @param string $field ('length','redirect','revision','model')
99		* @return string\|int\|null
100		*/
101		public function getGoodLinkFieldObj( LinkTarget $target, $field ) {
102		$dbkey = $this->titleFormatter->getPrefixedDBkey( $target );
103		$info = $this->mGoodLinks->get( $dbkey );
104		if ( !$info ) {
105		return null;
106		}
107		return $info[$field];
108		}
109
110		/**
111		* @param string $title Prefixed DB key
112		* @return bool
113		*/
114		public function isBadLink( $title ) {
115		// Use get() to ensure it records as used for LRU.
116		return $this->mBadLinks->get( $title ) !== false;
117		}
118
119		/**
120		* Add a link for the title to the link cache
121		*
122		* @param int $id Page's ID
123		* @param LinkTarget $target
124		* @param int $len Text's length
125		* @param int $redir Whether the page is a redirect
126		* @param int $revision Latest revision's ID
127		* @param string\|null $model Latest revision's content model ID
128		* @param string\|null $lang Language code of the page, if not the content language
129		*/
130		public function addGoodLinkObj( $id, LinkTarget $target, $len = -1, $redir = null,
131		$revision = 0, $model = null, $lang = null
132		) {
133		$dbkey = $this->titleFormatter->getPrefixedDBkey( $target );
134		$this->mGoodLinks->set( $dbkey, [
135		'id' => (int)$id,
136		'length' => (int)$len,
137		'redirect' => (int)$redir,
138		'revision' => (int)$revision,
139		'model' => $model ? (string)$model : null,
140		'lang' => $lang ? (string)$lang : null,
141		] );
142		}
143
144		/**
145		* Same as above with better interface.
146		* @since 1.19
147		* @param LinkTarget $target
148		* @param stdClass $row Object which has the fields page_id, page_is_redirect,
149		* page_latest and page_content_model
150		*/
151		public function addGoodLinkObjFromRow( LinkTarget $target, $row ) {
152		$dbkey = $this->titleFormatter->getPrefixedDBkey( $target );
153		$this->mGoodLinks->set( $dbkey, [
154		'id' => intval( $row->page_id ),
155		'length' => intval( $row->page_len ),
156		'redirect' => intval( $row->page_is_redirect ),
157		'revision' => intval( $row->page_latest ),
158		'model' => !empty( $row->page_content_model ) ? strval( $row->page_content_model ) : null,
159		'lang' => !empty( $row->page_lang ) ? strval( $row->page_lang ) : null,
160		] );
161		}
162
163		/**
164		* @param LinkTarget $target
165		*/
166		public function addBadLinkObj( LinkTarget $target ) {
167		$dbkey = $this->titleFormatter->getPrefixedDBkey( $target );
168		if ( !$this->isBadLink( $dbkey ) ) {
169		$this->mBadLinks->set( $dbkey, 1 );
170		}
171		}
172
173		/**
174		* @param string $title Prefixed DB key
175		*/
176		public function clearBadLink( $title ) {
177		$this->mBadLinks->delete( $title );
178		}
179
180		/**
181		* @param LinkTarget $target
182		*/
183		public function clearLink( LinkTarget $target ) {
184		$dbkey = $this->titleFormatter->getPrefixedDBkey( $target );
185		$this->mBadLinks->delete( $dbkey );
186		$this->mGoodLinks->delete( $dbkey );
187		}
188
189		/**
190		* Add a title to the link cache, return the page_id or zero if non-existent
191		*
192		* @deprecated since 1.27, unused
193		* @param string $title Prefixed DB key
194		* @return int Page ID or zero
195		*/
196		public function addLink( $title ) {
197		$nt = Title::newFromDBkey( $title );
198		if ( !$nt ) {
199		return 0;
200		}
201		return $this->addLinkObj( $nt );
202		}
203
204		/**
205		* Fields that LinkCache needs to select
206		*
207		* @since 1.28
208		* @return array
209		*/
210	View Code Duplication	public static function getSelectFields() {
211		global $wgContentHandlerUseDB, $wgPageLanguageUseDB;
212
213		$fields = [ 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ];
214		if ( $wgContentHandlerUseDB ) {
215		$fields[] = 'page_content_model';
216		}
217		if ( $wgPageLanguageUseDB ) {
218		$fields[] = 'page_lang';
219		}
220
221		return $fields;
222		}
223
224		/**
225		* Add a title to the link cache, return the page_id or zero if non-existent
226		*
227		* @param LinkTarget $nt LinkTarget object to add
228		* @return int Page ID or zero
229		*/
230		public function addLinkObj( LinkTarget $nt ) {
231		$key = $this->titleFormatter->getPrefixedDBkey( $nt );
232		if ( $this->isBadLink( $key ) \|\| $nt->isExternal()
233		\|\| $nt->inNamespace( NS_SPECIAL )
234		) {
235		return 0;
236		}
237		$id = $this->getGoodLinkID( $key );
238		if ( $id != 0 ) {
239		return $id;
240		}
241
242		if ( $key === '' ) {
243		return 0;
244		}
245
246		// Cache template/file pages as they are less often viewed but heavily used
247		if ( $this->mForUpdate ) {
248		$row = $this->fetchPageRow( wfGetDB( DB_MASTER ), $nt );
249		} elseif ( $this->isCacheable( $nt ) ) {
250		// These pages are often transcluded heavily, so cache them
251		$cache = $this->wanCache;
252		$row = $cache->getWithSetCallback(
253		$cache->makeKey( 'page', $nt->getNamespace(), sha1( $nt->getDBkey() ) ),
254		$cache::TTL_DAY,
255		function ( $curValue, &$ttl, array &$setOpts ) use ( $cache, $nt ) {
256		$dbr = wfGetDB( DB_REPLICA );
257		$setOpts += Database::getCacheSetOptions( $dbr );
258
259		$row = $this->fetchPageRow( $dbr, $nt );
260		$mtime = $row ? wfTimestamp( TS_UNIX, $row->page_touched ) : false;
261		$ttl = $cache->adaptiveTTL( $mtime, $ttl );
262
263		return $row;
264		}
265		);
266		} else {
267		$row = $this->fetchPageRow( wfGetDB( DB_REPLICA ), $nt );
268		}
269
270		if ( $row ) {
271		$this->addGoodLinkObjFromRow( $nt, $row );
272		$id = intval( $row->page_id );
273		} else {
274		$this->addBadLinkObj( $nt );
275		$id = 0;
276		}
277
278		return $id;
279		}
280
281		private function isCacheable( LinkTarget $title ) {
282		return ( $title->inNamespace( NS_TEMPLATE ) \|\| $title->inNamespace( NS_FILE ) );
283		}
284
285		private function fetchPageRow( IDatabase $db, LinkTarget $nt ) {
286		$fields = self::getSelectFields();
287		if ( $this->isCacheable( $nt ) ) {
288		$fields[] = 'page_touched';
289		}
290
291		return $db->selectRow(
292		'page',
293		$fields,
294		[ 'page_namespace' => $nt->getNamespace(), 'page_title' => $nt->getDBkey() ],
295		__METHOD__
296		);
297		}
298
299		/**
300		* Purge the link cache for a title
301		*
302		* @param LinkTarget $title
303		* @since 1.28
304		*/
305		public function invalidateTitle( LinkTarget $title ) {
306		if ( $this->isCacheable( $title ) ) {
307		$cache = ObjectCache::getMainWANInstance();
308		$cache->delete(
309		$cache->makeKey( 'page', $title->getNamespace(), sha1( $title->getDBkey() ) )
310		);
311		}
312		}
313
314		/**
315		* Clears cache
316		*/
317		public function clear() {
318		$this->mGoodLinks->clear();
319		$this->mBadLinks->clear();
320		}
321		}
322

wikimedia / mediawiki

Branch — master (fc4983)

LinkCache::isCacheable() A

Complexity

Size

Duplication

Importance

Duplication Side-by-Side

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