1
|
|
|
<?php
|
2
|
|
|
namespace AutoLock;
|
3
|
|
|
use AutoLock\Exception\ManagerCompareException;
|
4
|
|
|
|
5
|
|
|
/**
|
6
|
|
|
* Class Manager is using to create lock and release lock
|
7
|
|
|
* using pool.
|
8
|
|
|
*
|
9
|
|
|
* @package AutoLock
|
10
|
|
|
* @author Liu Lu <[email protected]>
|
11
|
|
|
* @since 0.1
|
12
|
|
|
*/
|
13
|
|
|
class Manager
|
14
|
|
|
{
|
15
|
|
|
const MIN_DRIFT = 2;
|
16
|
|
|
|
17
|
|
|
const UNLOCK_SCRIPT = '
|
18
|
|
|
if redis.call("GET", KEYS[1]) == ARGV[1] then
|
19
|
|
|
return redis.call("DEL", KEYS[1])
|
20
|
|
|
else
|
21
|
|
|
return 0
|
22
|
|
|
end
|
23
|
|
|
';
|
24
|
|
|
|
25
|
|
|
/**
|
26
|
|
|
* @var int Delay millisecond after fail to get lock
|
27
|
|
|
*/
|
28
|
|
|
private $retryDelay;
|
29
|
|
|
/**
|
30
|
|
|
* @var int Number of times after fail to get lock
|
31
|
|
|
*/
|
32
|
|
|
private $retryCount;
|
33
|
|
|
/**
|
34
|
|
|
* @var float
|
35
|
|
|
* Clock drift coefficient,
|
36
|
|
|
* to prevent redis and web time to pass the speed of different,
|
37
|
|
|
* resulting in lock early failure of the insurance value
|
38
|
|
|
*/
|
39
|
|
|
private $clockDriftFactor = 0.01;
|
40
|
|
|
/**
|
41
|
|
|
* @var Pool
|
42
|
|
|
*/
|
43
|
|
|
private $pool;
|
44
|
|
|
|
45
|
|
|
|
46
|
21 |
|
public function __construct(Pool $pool, $retryDelay = 200, $retryCount = 3)
|
47
|
|
|
{
|
48
|
21 |
|
$this->pool = $pool;
|
49
|
21 |
|
$this->retryDelay = $retryDelay;
|
50
|
21 |
|
$this->retryCount = $retryCount;
|
51
|
21 |
|
}
|
52
|
|
|
|
53
|
|
|
/**
|
54
|
|
|
* $ttl's unit is milliseconds, min $ttl is 2 milliseconds which means you will aways
|
55
|
|
|
* get a lock which is expired
|
56
|
|
|
* @param string $resource
|
57
|
|
|
* @param int $ttl
|
58
|
|
|
* @param bool $autoRelease
|
59
|
|
|
* @return Lock|bool
|
60
|
|
|
*/
|
61
|
5 |
|
public function lock($resource, $ttl, $autoRelease = false)
|
62
|
|
|
{
|
63
|
|
|
//@todo 验证$ttl > 0
|
64
|
5 |
|
$ttl = (int)$ttl;
|
65
|
5 |
|
$resource = (string)$resource;
|
66
|
5 |
|
$token = uniqid();
|
67
|
5 |
|
$retry = $this->retryCount;
|
68
|
|
|
do {
|
69
|
5 |
|
$n = 0;
|
70
|
5 |
|
$startTime = microtime(true) * 1000;
|
71
|
5 |
|
foreach ($this->pool as $server) {
|
72
|
|
|
/**
|
73
|
|
|
* @var $server Server
|
74
|
|
|
*/
|
75
|
5 |
|
if ($server->set($resource, $token, array('NX', 'PX' => $ttl))) {
|
76
|
5 |
|
$n++;
|
77
|
|
|
}
|
78
|
|
|
}
|
79
|
|
|
# Add 2 milliseconds to the drift to account for Redis expires
|
80
|
|
|
# precision, which is 1 millisecond, plus 1 millisecond min drift
|
81
|
|
|
# for small TTLs.
|
82
|
5 |
|
$drift = ($ttl * $this->clockDriftFactor) + self::MIN_DRIFT;
|
83
|
5 |
|
$validityTime = $ttl - (microtime(true) * 1000 - $startTime) - $drift;
|
84
|
5 |
|
if ($this->pool->checkQuorum($n) && $validityTime > 0) {
|
85
|
3 |
|
return new Lock($this, $validityTime, $resource, $token, $autoRelease);
|
86
|
|
|
} else {
|
87
|
2 |
|
foreach ($this->pool as $server) {
|
88
|
|
|
/**
|
89
|
|
|
* @var $server Server
|
90
|
|
|
*/
|
91
|
2 |
|
$this->unlockServer($server, $resource, $token);
|
92
|
|
|
}
|
93
|
|
|
}
|
94
|
|
|
// Wait a random delay before to retry
|
95
|
2 |
|
$delay = mt_rand(floor($this->retryDelay / 2), $this->retryDelay);
|
96
|
2 |
|
usleep($delay * 1000);
|
97
|
2 |
|
$retry--;
|
98
|
2 |
|
} while ($retry > 0);
|
99
|
2 |
|
return false;
|
100
|
|
|
}
|
101
|
|
|
|
102
|
|
|
/**
|
103
|
|
|
* @param Lock $lock
|
104
|
|
|
* @throws ManagerCompareException
|
105
|
|
|
*/
|
106
|
6 |
|
public function unlock(Lock $lock)
|
107
|
|
|
{
|
108
|
6 |
|
if ($lock->getManager() !== $this) {
|
109
|
1 |
|
throw new ManagerCompareException('You must unlock with the manager who create it');
|
110
|
|
|
}
|
111
|
5 |
|
$resource = $lock->getResource();
|
112
|
5 |
|
$token = $lock->getToken();
|
113
|
5 |
|
foreach ($this->pool as $server) {
|
114
|
5 |
|
self::unlockServer($server, $resource, $token);
|
115
|
|
|
}
|
116
|
5 |
|
}
|
117
|
|
|
|
118
|
7 |
|
private static function unlockServer(Server $server, $resource, $token)
|
119
|
|
|
{
|
120
|
7 |
|
$script = self::UNLOCK_SCRIPT;
|
121
|
7 |
|
$server->evalScript($script, array($resource, $token));
|
122
|
7 |
|
}
|
123
|
|
|
|
124
|
10 |
|
public function available()
|
125
|
|
|
{
|
126
|
10 |
|
$onLineServersNumber = 0;
|
127
|
10 |
|
foreach ($this->pool as $server) {
|
128
|
|
|
/**
|
129
|
|
|
* @var $server Server
|
130
|
|
|
*/
|
131
|
9 |
|
if ($server->available()) {
|
132
|
9 |
|
$onLineServersNumber++;
|
133
|
|
|
}
|
134
|
|
|
}
|
135
|
10 |
|
if ($this->pool->checkQuorum($onLineServersNumber)) {
|
136
|
4 |
|
return true;
|
137
|
|
|
} else {
|
138
|
6 |
|
return false;
|
139
|
|
|
}
|
140
|
|
|
}
|
141
|
|
|
} |