|
1
|
|
|
<?php |
|
2
|
|
|
/** |
|
3
|
|
|
* This file is part of the Rate Limit package. |
|
4
|
|
|
* |
|
5
|
|
|
* Copyright (c) Nikola Posa |
|
6
|
|
|
* |
|
7
|
|
|
* For full copyright and license information, please refer to the LICENSE file, |
|
8
|
|
|
* located at the package root folder. |
|
9
|
|
|
*/ |
|
10
|
|
|
|
|
11
|
|
|
declare(strict_types=1); |
|
12
|
|
|
|
|
13
|
|
|
namespace RateLimit; |
|
14
|
|
|
|
|
15
|
|
|
use Psr\Http\Message\RequestInterface; |
|
16
|
|
|
use Psr\Http\Message\ResponseInterface; |
|
17
|
|
|
use RateLimit\Storage\StorageInterface; |
|
18
|
|
|
use RateLimit\Identity\IdentityGeneratorInterface; |
|
19
|
|
|
use RateLimit\Identity\IpAddressIdentityGenerator; |
|
20
|
|
|
use RateLimit\Exception\StorageRecordNotExistException; |
|
21
|
|
|
|
|
22
|
|
|
/** |
|
23
|
|
|
* @author Nikola Posa <[email protected]> |
|
24
|
|
|
*/ |
|
25
|
|
|
final class RequestsPerWindowRateLimiter implements RateLimiterInterface |
|
26
|
|
|
{ |
|
27
|
|
|
const LIMIT_EXCEEDED_HTTP_STATUS_CODE = 429; //HTTP 429 "Too Many Requests" (RFC 6585) |
|
28
|
|
|
|
|
29
|
|
|
const HEADER_LIMIT = 'X-RateLimit-Limit'; |
|
30
|
|
|
const HEADER_REMAINING = 'X-RateLimit-Remaining'; |
|
31
|
|
|
const HEADER_RESET = 'X-RateLimit-Reset'; |
|
32
|
|
|
|
|
33
|
|
|
/** |
|
34
|
|
|
* @var StorageInterface |
|
35
|
|
|
*/ |
|
36
|
|
|
private $storage; |
|
37
|
|
|
|
|
38
|
|
|
/** |
|
39
|
|
|
* @var array |
|
40
|
|
|
*/ |
|
41
|
|
|
private $options; |
|
42
|
|
|
|
|
43
|
|
|
/** |
|
44
|
|
|
* @var IdentityGeneratorInterface |
|
45
|
|
|
*/ |
|
46
|
|
|
private $identityGenerator; |
|
47
|
|
|
|
|
48
|
|
|
/** |
|
49
|
|
|
* @var array |
|
50
|
|
|
*/ |
|
51
|
|
|
private $rateLimit; |
|
52
|
|
|
|
|
53
|
|
|
/** |
|
54
|
|
|
* @var array |
|
55
|
|
|
*/ |
|
56
|
|
|
private static $defaultOptions = [ |
|
57
|
|
|
'limit' => 100, |
|
58
|
|
|
'window' => 900, //15 minutes |
|
59
|
|
|
'limitExceededHandler' => null, |
|
60
|
|
|
]; |
|
61
|
|
|
|
|
62
|
2 |
|
private function __construct(StorageInterface $storage, array $options, IdentityGeneratorInterface $identityGenerator) |
|
63
|
|
|
{ |
|
64
|
2 |
|
$this->storage = $storage; |
|
65
|
2 |
|
$this->options = $options; |
|
66
|
2 |
|
$this->identityGenerator = $identityGenerator; |
|
67
|
2 |
|
} |
|
68
|
|
|
|
|
69
|
2 |
|
public static function create(StorageInterface $storage, array $options = [], IdentityGeneratorInterface $identityGenerator = null) |
|
70
|
|
|
{ |
|
71
|
2 |
|
return new self( |
|
72
|
|
|
$storage, |
|
73
|
2 |
|
array_merge(self::$defaultOptions, $options), |
|
74
|
2 |
|
$identityGenerator ?? new IpAddressIdentityGenerator() |
|
75
|
|
|
); |
|
76
|
|
|
} |
|
77
|
|
|
|
|
78
|
|
|
/** |
|
79
|
|
|
* {@inheritdoc} |
|
80
|
|
|
*/ |
|
81
|
2 |
|
public function __invoke(RequestInterface $request, ResponseInterface $response, callable $out = null) |
|
82
|
|
|
{ |
|
83
|
2 |
|
$key = $this->identityGenerator->getIdentity($request); |
|
84
|
|
|
|
|
85
|
2 |
|
$this->initRateLimit($key); |
|
86
|
|
|
|
|
87
|
2 |
|
if ($this->isLimitExceeded()) { |
|
88
|
2 |
|
return $this->onLimitExceeded($request, $response); |
|
89
|
|
|
} |
|
90
|
|
|
|
|
91
|
2 |
|
if ($this->shouldResetRateLimit()) { |
|
92
|
|
|
$this->resetRateLimit(); |
|
93
|
|
|
} else { |
|
94
|
2 |
|
$this->updateRateLimit(); |
|
95
|
|
|
} |
|
96
|
|
|
|
|
97
|
2 |
|
$this->storage->set($key, $this->rateLimit); |
|
98
|
|
|
|
|
99
|
2 |
|
return $this->onBelowLimit($request, $response, $out); |
|
100
|
|
|
} |
|
101
|
|
|
|
|
102
|
2 |
|
private function initRateLimit(string $key) |
|
103
|
|
|
{ |
|
104
|
|
|
try { |
|
105
|
2 |
|
$rateLimit = $this->storage->get($key); |
|
106
|
2 |
|
} catch (StorageRecordNotExistException $ex) { |
|
107
|
|
|
$rateLimit = [ |
|
108
|
2 |
|
'remaining' => $this->options['limit'], |
|
109
|
2 |
|
'reset' => time() + $this->options['window'], |
|
110
|
|
|
]; |
|
111
|
|
|
} |
|
112
|
|
|
|
|
113
|
2 |
|
$this->rateLimit = $rateLimit; |
|
|
|
|
|
|
114
|
2 |
|
} |
|
115
|
|
|
|
|
116
|
2 |
|
private function isLimitExceeded() : bool |
|
117
|
|
|
{ |
|
118
|
2 |
|
return $this->rateLimit['remaining'] <= 0; |
|
119
|
|
|
} |
|
120
|
|
|
|
|
121
|
2 |
|
private function updateRateLimit() |
|
122
|
|
|
{ |
|
123
|
2 |
|
$this->rateLimit['remaining']--; |
|
124
|
2 |
|
} |
|
125
|
|
|
|
|
126
|
2 |
|
private function shouldResetRateLimit() : bool |
|
127
|
|
|
{ |
|
128
|
2 |
|
return time() >= $this->rateLimit['reset']; |
|
129
|
|
|
} |
|
130
|
|
|
|
|
131
|
|
|
private function resetRateLimit() |
|
132
|
|
|
{ |
|
133
|
|
|
$this->rateLimit = [ |
|
134
|
|
|
'remaining' => $this->options['limit'], |
|
135
|
|
|
'reset' => time() + $this->options['window'], |
|
136
|
|
|
]; |
|
137
|
|
|
} |
|
138
|
|
|
|
|
139
|
2 |
|
private function onLimitExceeded(RequestInterface $request, ResponseInterface $response) : ResponseInterface |
|
140
|
|
|
{ |
|
141
|
|
|
$response = $this |
|
142
|
2 |
|
->setRateLimitHeaders($response) |
|
143
|
2 |
|
->withStatus(self::LIMIT_EXCEEDED_HTTP_STATUS_CODE) |
|
144
|
|
|
; |
|
145
|
|
|
|
|
146
|
2 |
|
$limitExceededHandler = $this->options['limitExceededHandler']; |
|
147
|
|
|
|
|
148
|
2 |
|
if (null !== $limitExceededHandler && is_callable($limitExceededHandler)) { |
|
149
|
|
|
$response = $limitExceededHandler($request, $response); |
|
150
|
|
|
} |
|
151
|
|
|
|
|
152
|
2 |
|
return $response; |
|
153
|
|
|
} |
|
154
|
|
|
|
|
155
|
2 |
|
private function onBelowLimit(RequestInterface $request, ResponseInterface $response, callable $out = null) : ResponseInterface |
|
156
|
|
|
{ |
|
157
|
2 |
|
$response = $this->setRateLimitHeaders($response); |
|
158
|
|
|
|
|
159
|
2 |
|
return $out ? $out($request, $response) : $response; |
|
160
|
|
|
} |
|
161
|
|
|
|
|
162
|
2 |
|
private function setRateLimitHeaders(ResponseInterface $response) : ResponseInterface |
|
163
|
|
|
{ |
|
164
|
|
|
return $response |
|
165
|
2 |
|
->withHeader(self::HEADER_LIMIT, (string) $this->options['limit']) |
|
166
|
2 |
|
->withHeader(self::HEADER_REMAINING, (string) $this->rateLimit['remaining']) |
|
167
|
2 |
|
->withHeader(self::HEADER_RESET, (string) $this->rateLimit['reset']) |
|
168
|
|
|
; |
|
169
|
|
|
} |
|
170
|
|
|
} |
|
171
|
|
|
|
Our type inference engine has found an assignment to a property that is incompatible with the declared type of that property.
Either this assignment is in error or the assigned type should be added to the documentation/type hint for that property..