Completed
Push — php-74-ci ( 3d1af5...9001b7 )
by Alexander
24:14 queued 23:56
created

Dependency::evaluateDependency()   A

Complexity

Conditions 3
Paths 3

Size

Total Lines 10
Code Lines 7

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 3
CRAP Score 4.679

Importance

Changes 0
Metric Value
cc 3
eloc 7
nc 3
nop 1
dl 0
loc 10
ccs 3
cts 7
cp 0.4286
crap 4.679
rs 10
c 0
b 0
f 0
1
<?php
2
/**
3
 * @link http://www.yiiframework.com/
4
 * @copyright Copyright (c) 2008 Yii Software LLC
5
 * @license http://www.yiiframework.com/license/
6
 */
7
8
namespace yii\caching;
9
10
/**
11
 * Dependency is the base class for cache dependency classes.
12
 *
13
 * Child classes should override its [[generateDependencyData()]] for generating
14
 * the actual dependency data.
15
 *
16
 * For more details and usage information on Cache, see the [guide article on caching](guide:caching-overview).
17
 *
18
 * @author Qiang Xue <[email protected]>
19
 * @since 2.0
20
 */
21
abstract class Dependency extends \yii\base\BaseObject
22
{
23
    /**
24
     * @var mixed the dependency data that is saved in cache and later is compared with the
25
     * latest dependency data.
26
     */
27
    public $data;
28
    /**
29
     * @var bool whether this dependency is reusable or not. True value means that dependent
30
     * data for this cache dependency will be generated only once per request. This allows you
31
     * to use the same cache dependency for multiple separate cache calls while generating the same
32
     * page without an overhead of re-evaluating dependency data each time. Defaults to false.
33
     */
34
    public $reusable = false;
35
36
    /**
37
     * @var array static storage of cached data for reusable dependencies.
38
     */
39
    private static $_reusableData = [];
40
41
42
    /**
43
     * Evaluates the dependency by generating and saving the data related with dependency.
44
     * This method is invoked by cache before writing data into it.
45
     * @param CacheInterface $cache the cache component that is currently evaluating this dependency
46
     */
47 36
    public function evaluateDependency($cache)
48
    {
49 36
        if ($this->reusable) {
50
            $hash = $this->generateReusableHash();
51
            if (!array_key_exists($hash, self::$_reusableData)) {
52
                self::$_reusableData[$hash] = $this->generateDependencyData($cache);
53
            }
54
            $this->data = self::$_reusableData[$hash];
55
        } else {
56 36
            $this->data = $this->generateDependencyData($cache);
57
        }
58 36
    }
59
60
    /**
61
     * Returns a value indicating whether the dependency has changed.
62
     * @deprecated since version 2.0.11. Will be removed in version 2.1. Use [[isChanged()]] instead.
63
     * @param CacheInterface $cache the cache component that is currently evaluating this dependency
64
     * @return bool whether the dependency has changed.
65
     */
66
    public function getHasChanged($cache)
67
    {
68
        return $this->isChanged($cache);
69
    }
70
71
    /**
72
     * Checks whether the dependency is changed.
73
     * @param CacheInterface $cache the cache component that is currently evaluating this dependency
74
     * @return bool whether the dependency has changed.
75
     * @since 2.0.11
76
     */
77 6
    public function isChanged($cache)
78
    {
79 6
        if ($this->reusable) {
80
            $hash = $this->generateReusableHash();
81
            if (!array_key_exists($hash, self::$_reusableData)) {
82
                self::$_reusableData[$hash] = $this->generateDependencyData($cache);
83
            }
84
            $data = self::$_reusableData[$hash];
85
        } else {
86 6
            $data = $this->generateDependencyData($cache);
87
        }
88
89 6
        return $data !== $this->data;
90
    }
91
92
    /**
93
     * Resets all cached data for reusable dependencies.
94
     */
95 1
    public static function resetReusableData()
96
    {
97 1
        self::$_reusableData = [];
98 1
    }
99
100
    /**
101
     * Generates a unique hash that can be used for retrieving reusable dependency data.
102
     * @return string a unique hash value for this cache dependency.
103
     * @see reusable
104
     */
105 1
    protected function generateReusableHash()
106
    {
107 1
        $data = $this->data;
108 1
        $this->data = null;  // https://github.com/yiisoft/yii2/issues/3052
109 1
        $key = sha1(serialize($this));
110 1
        $this->data = $data;
111 1
        return $key;
112
    }
113
114
    /**
115
     * Generates the data needed to determine if dependency is changed.
116
     * Derived classes should override this method to generate the actual dependency data.
117
     * @param CacheInterface $cache the cache component that is currently evaluating this dependency
118
     * @return mixed the data needed to determine if dependency has been changed.
119
     */
120
    abstract protected function generateDependencyData($cache);
121
}
122