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
|
<?php
/**
* Elgg memcache support.
*
* Requires php5-memcache to work.
*
* @package Elgg
* @subpackage API
* @license http://www.gnu.org/licenses/old-licenses/gpl-2.0.html GNU Public License version 2
* @author Curverider Ltd <info@elgg.com>
* @copyright Curverider Ltd 2008
* @link http://elgg.org/
*/
/**
* Memcache wrapper class.
* @author Curverider Ltd <info@elgg.com>
*/
class ElggMemcache extends ElggSharedMemoryCache
{
/**
* Minimum version of memcached needed to run
*
*/
private static $MINSERVERVERSION = '1.1.12';
/**
* Memcache object
*/
private $memcache;
/**
* Expiry of saved items (default timeout after a day to prevent anything getting too stale)
*/
private $expires = 86400;
/**
* The version of memcache running
*/
private $version = 0;
/**
* Keys so far.
* This variable holds a list of keys we have seen so that when we call ->clear() we invalidate only those keys.
* TODO: Could this be done better?
*/
private $keys_so_far = array();
/**
* Connect to memcache.
*
* @param string $cache_id The namespace for this cache to write to - note, namespaces of the same name are shared!
*/
function __construct($namespace = 'default')
{
global $CONFIG;
$this->setNamespace($namespace);
// Do we have memcache?
if (!class_exists('Memcache'))
throw new ConfigurationException(elgg_echo('memcache:notinstalled'));
// Create memcache object
$this->memcache = new Memcache;
// Now add servers
if (!$CONFIG->memcache_servers)
throw new ConfigurationException(elgg_echo('memcache:noservers'));
if (is_callable($this->memcache, 'addServer'))
{
foreach ($CONFIG->memcache_servers as $server)
{
if (is_array($server))
{
$this->memcache->addServer(
$server[0],
isset($server[1]) ? $server[1] : 11211,
isset($server[2]) ? $server[2] : true,
isset($server[3]) ? $server[3] : null,
isset($server[4]) ? $server[4] : 1,
isset($server[5]) ? $server[5] : 15,
isset($server[6]) ? $server[6] : true
);
}
else
$this->memcache->addServer($server, 11211);
}
}
else
{
if ((isset($CONFIG->debug)) && ($CONFIG->debug == true))
error_log(elgg_echo('memcache:noaddserver'));
$server = $CONFIG->memcache_servers[0];
if (is_array($server))
{
$this->memcache->connect($server[0], $server[1]);
}
else
$this->memcache->addServer($server, 11211);
}
// Get version
$this->version = $this->memcache->getversion();
if (version_compare($this->version, ElggMemcache::$MINSERVERVERSION, '<'))
throw new ConfigurationException(sprintf(elgg_echo('memcache:versiontoolow'), ElggMemcache::$MINSERVERVERSION, $this->version));
// Set some defaults
if (isset($CONFIG->memcache_expires))
$this->expires = $CONFIG->memcache_expires;
}
/**
* Set the default expiry.
*
* @param int $expires The lifetime as a unix timestamp or time from now. Defaults forever.
*/
public function setDefaultExpiry($expires = 0)
{
$this->expires = $expires;
}
/**
* Combine a key with the namespace.
* Memcache can only accept <250 char key. If the given key is too long it is shortened.
*
* @param string $key The key
* @return string The new key.
*/
private function make_memcache_key($key)
{
$prefix = $this->getNamespace() . ":";
if (strlen($prefix.$key)> 250)
$key = md5($key);
return $prefix.$key;
}
public function save($key, $data)
{
$key = $this->make_memcache_key($key);
$this->keys_so_far[$key] = time();
//$this->save_persistent_keylist();
$result = $this->memcache->set($key, $data, null, $this->expires);
if ((isset($CONFIG->debug)) && ($CONFIG->debug == true) && (!$result))
error_log("MEMCACHE: FAILED TO SAVE $key");
return $result;
}
public function load($key, $offset = 0, $limit = null)
{
$key = $this->make_memcache_key($key);
$this->keys_so_far[$key] = time();
//$this->save_persistent_keylist();
$result = $this->memcache->get($key);
if ((isset($CONFIG->debug)) && ($CONFIG->debug == true) && (!$result))
error_log("MEMCACHE: FAILED TO LOAD $key");
return $result;
}
public function delete($key)
{
$key = $this->make_memcache_key($key);
return $this->memcache->delete($key, 0);
}
public function clear()
{
// DISABLE clearing for now - you must use delete on a specific key.
return true;
foreach ($this->keys_so_far as $key => $ts)
$this->memcache->delete($key, 0);
//$this->clear_persistent_keylist();
$this->keys_so_far = array();
return true;
}
/*private function load_persistent_keylist()
{
return $this->memcache->get($this->getNamespace().':keys_so_far');
}
private function save_persistent_keylist()
{
$stored = $this->load_persistent_keylist();
if ($stored) $this->keys_so_far = array_merge($this->keys_so_far, $stored);
return $this->memcache->set($this->getNamespace().':keys_so_far', $this->keys_so_far, null, 0);
}
private function clear_persistent_keylist()
{
return $this->memcache->delete($this->getNamespace().':keys_so_far', 0);
}
public function __destruct()
{
$this->save_persistent_keylist();
}*/
}
?>
|
