summaryrefslogtreecommitdiff
path: root/includes/cache/UserCache.php
blob: bfbacfaaa9973fb2afdd4cdfa7221a7c640ce5e5 (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
<?php
/**
 * Caches current user names and other info based on user IDs.
 *
 * 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
 */

/**
 * @since 1.20
 */
class UserCache {
	protected $cache = array(); // (uid => property => value)
	protected $typesCached = array(); // (uid => cache type => 1)

	/**
	 * @return UserCache
	 */
	public static function singleton() {
		static $instance = null;
		if ( $instance === null ) {
			$instance = new self();
		}
		return $instance;
	}

	protected function __construct() {}

	/**
	 * Get a property of a user based on their user ID
	 *
	 * @param $userId integer User ID
	 * @param string $prop User property
	 * @return mixed The property or false if the user does not exist
	 */
	public function getProp( $userId, $prop ) {
		if ( !isset( $this->cache[$userId][$prop] ) ) {
			wfDebug( __METHOD__ . ": querying DB for prop '$prop' for user ID '$userId'.\n" );
			$this->doQuery( array( $userId ) ); // cache miss
		}
		return isset( $this->cache[$userId][$prop] )
			? $this->cache[$userId][$prop]
			: false; // user does not exist?
	}

	/**
	 * Preloads user names for given list of users.
	 * @param array $userIds List of user IDs
	 * @param array $options Option flags; include 'userpage' and 'usertalk'
	 * @param string $caller the calling method
	 */
	public function doQuery( array $userIds, $options = array(), $caller = '' ) {
		wfProfileIn( __METHOD__ );

		$usersToCheck = array();
		$usersToQuery = array();

		foreach ( $userIds as $userId ) {
			$userId = (int)$userId;
			if ( $userId <= 0 ) {
				continue; // skip anons
			}
			if ( isset( $this->cache[$userId]['name'] ) ) {
				$usersToCheck[$userId] = $this->cache[$userId]['name']; // already have name
			} else {
				$usersToQuery[] = $userId; // we need to get the name
			}
		}

		// Lookup basic info for users not yet loaded...
		if ( count( $usersToQuery ) ) {
			$dbr = wfGetDB( DB_SLAVE );
			$table = array( 'user' );
			$conds = array( 'user_id' => $usersToQuery );
			$fields = array( 'user_name', 'user_real_name', 'user_registration', 'user_id' );

			$comment = __METHOD__;
			if ( strval( $caller ) !== '' ) {
				$comment .= "/$caller";
			}

			$res = $dbr->select( $table, $fields, $conds, $comment );
			foreach ( $res as $row ) { // load each user into cache
				$userId = (int)$row->user_id;
				$this->cache[$userId]['name'] = $row->user_name;
				$this->cache[$userId]['real_name'] = $row->user_real_name;
				$this->cache[$userId]['registration'] = $row->user_registration;
				$usersToCheck[$userId] = $row->user_name;
			}
		}

		$lb = new LinkBatch();
		foreach ( $usersToCheck as $userId => $name ) {
			if ( $this->queryNeeded( $userId, 'userpage', $options ) ) {
				$lb->add( NS_USER, str_replace( ' ', '_', $row->user_name ) );
				$this->typesCached[$userId]['userpage'] = 1;
			}
			if ( $this->queryNeeded( $userId, 'usertalk', $options ) ) {
				$lb->add( NS_USER_TALK, str_replace( ' ', '_', $row->user_name ) );
				$this->typesCached[$userId]['usertalk'] = 1;
			}
		}
		$lb->execute();

		wfProfileOut( __METHOD__ );
	}

	/**
	 * Check if a cache type is in $options and was not loaded for this user
	 *
	 * @param $uid integer user ID
	 * @param string $type Cache type
	 * @param array $options Requested cache types
	 * @return bool
	 */
	protected function queryNeeded( $uid, $type, array $options ) {
		return ( in_array( $type, $options ) && !isset( $this->typesCached[$uid][$type] ) );
	}
}