1
|
|
|
<?php |
2
|
|
|
|
3
|
|
|
namespace SilverStripe\Core; |
4
|
|
|
|
5
|
|
|
use BadMethodCallException; |
6
|
|
|
use SilverStripe\ORM\DataObject; |
7
|
|
|
|
8
|
|
|
/** |
9
|
|
|
* Add extension that can be added to an object with {@link Object::add_extension()}. |
10
|
|
|
* For {@link DataObject} extensions, use {@link DataExtension}. |
11
|
|
|
* Each extension instance has an "owner" instance, accessible through |
12
|
|
|
* {@link getOwner()}. |
13
|
|
|
* Every object instance gets its own set of extension instances, |
14
|
|
|
* meaning you can set parameters specific to the "owner instance" |
15
|
|
|
* in new Extension instances. |
16
|
|
|
*/ |
17
|
|
|
abstract class Extension |
18
|
|
|
{ |
19
|
|
|
/** |
20
|
|
|
* This is used by extensions designed to be applied to controllers. |
21
|
|
|
* It works the same way as {@link Controller::$allowed_actions}. |
22
|
|
|
*/ |
23
|
|
|
private static $allowed_actions = []; |
|
|
|
|
24
|
|
|
|
25
|
|
|
/** |
26
|
|
|
* The object this extension is applied to. |
27
|
|
|
* |
28
|
|
|
* @var Object |
29
|
|
|
*/ |
30
|
|
|
protected $owner; |
31
|
|
|
|
32
|
|
|
/** |
33
|
|
|
* Stack of all parent owners, not including current owner |
34
|
|
|
* |
35
|
|
|
* @var array |
36
|
|
|
*/ |
37
|
|
|
private $ownerStack = []; |
38
|
|
|
|
39
|
|
|
public function __construct() |
40
|
|
|
{ |
41
|
|
|
} |
42
|
|
|
|
43
|
|
|
/** |
44
|
|
|
* Called when this extension is added to a particular class |
45
|
|
|
* |
46
|
|
|
* @param string $class |
47
|
|
|
* @param string $extensionClass |
48
|
|
|
* @param mixed $args |
49
|
|
|
*/ |
50
|
|
|
public static function add_to_class($class, $extensionClass, $args = null) |
51
|
|
|
{ |
52
|
|
|
// NOP |
53
|
|
|
} |
54
|
|
|
|
55
|
|
|
/** |
56
|
|
|
* Set the owner of this extension. |
57
|
|
|
* |
58
|
|
|
* @param object $owner The owner object |
59
|
|
|
*/ |
60
|
|
|
public function setOwner($owner) |
61
|
|
|
{ |
62
|
|
|
$this->ownerStack[] = $this->owner; |
63
|
|
|
$this->owner = $owner; |
64
|
|
|
} |
65
|
|
|
|
66
|
|
|
/** |
67
|
|
|
* Temporarily modify the owner. The original owner is ensured to be restored |
68
|
|
|
* |
69
|
|
|
* @param mixed $owner Owner to set |
70
|
|
|
* @param callable $callback Callback to invoke |
71
|
|
|
* @param array $args Args to pass to callback |
72
|
|
|
* @return mixed |
73
|
|
|
*/ |
74
|
|
|
public function withOwner($owner, callable $callback, $args = []) |
75
|
|
|
{ |
76
|
|
|
try { |
77
|
|
|
$this->setOwner($owner); |
78
|
|
|
return $callback(...$args); |
79
|
|
|
} finally { |
80
|
|
|
$this->clearOwner(); |
81
|
|
|
} |
82
|
|
|
} |
83
|
|
|
|
84
|
|
|
/** |
85
|
|
|
* Clear the current owner, and restore extension to the state prior to the last setOwner() |
86
|
|
|
*/ |
87
|
|
|
public function clearOwner() |
88
|
|
|
{ |
89
|
|
|
if (empty($this->ownerStack)) { |
90
|
|
|
throw new BadMethodCallException("clearOwner() called more than setOwner()"); |
91
|
|
|
} |
92
|
|
|
$this->owner = array_pop($this->ownerStack); |
93
|
|
|
} |
94
|
|
|
|
95
|
|
|
/** |
96
|
|
|
* Returns the owner of this extension. |
97
|
|
|
* |
98
|
|
|
* @return Object |
99
|
|
|
*/ |
100
|
|
|
public function getOwner() |
101
|
|
|
{ |
102
|
|
|
return $this->owner; |
103
|
|
|
} |
104
|
|
|
|
105
|
|
|
/** |
106
|
|
|
* Helper method to strip eval'ed arguments from a string |
107
|
|
|
* that's passed to {@link DataObject::$extensions} or |
108
|
|
|
* {@link Object::add_extension()}. |
109
|
|
|
* |
110
|
|
|
* @param string $extensionStr E.g. "Versioned('Stage','Live')" |
111
|
|
|
* @return string Extension classname, e.g. "Versioned" |
112
|
|
|
*/ |
113
|
|
|
public static function get_classname_without_arguments($extensionStr) |
114
|
|
|
{ |
115
|
|
|
// Split out both args and service name |
116
|
|
|
return strtok(strtok($extensionStr, '('), '.'); |
117
|
|
|
} |
118
|
|
|
|
119
|
|
|
/** |
120
|
|
|
* Invoke extension point. This will prefer explicit `extend` prefixed |
121
|
|
|
* methods. |
122
|
|
|
* |
123
|
|
|
* @param object $owner |
124
|
|
|
* @param string $method |
125
|
|
|
* @param array &...$arguments |
126
|
|
|
* @return mixed |
127
|
|
|
*/ |
|
|
|
|
128
|
|
|
public function invokeExtension($owner, $method, &...$arguments) |
129
|
|
|
{ |
130
|
|
|
// Prefer `extend` prefixed methods |
131
|
|
|
$instanceMethod = method_exists($this, "extend{$method}") |
132
|
|
|
? "extend{$method}" |
133
|
|
|
: (method_exists($this, $method) ? $method : null); |
134
|
|
|
if (!$instanceMethod) { |
135
|
|
|
return null; |
136
|
|
|
} |
137
|
|
|
|
138
|
|
|
try { |
139
|
|
|
$this->setOwner($owner); |
140
|
|
|
return $this->$instanceMethod(...$arguments); |
141
|
|
|
} finally { |
142
|
|
|
$this->clearOwner(); |
143
|
|
|
} |
144
|
|
|
} |
145
|
|
|
} |
146
|
|
|
|