media-cloud-sync / includes / sdk / s3 / Aws / Signature / SignatureProvider.php

SignatureProvider.php in Media Cloud Sync 1.4.1, at includes/sdk/s3/Aws/Signature/SignatureProvider.php

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1	<?php
2
3	namespace Dudlewebs\WPMCS\s3\Aws\Signature;
4
5	use Dudlewebs\WPMCS\s3\Aws\Exception\UnresolvedSignatureException;
6	use Dudlewebs\WPMCS\s3\Aws\Token\BearerTokenAuthorization;
7	/**
8	* Signature providers.
9	*
10	* A signature provider is a function that accepts a version, service, and
11	* region and returns a {@see SignatureInterface} object on success or NULL if
12	* no signature can be created from the provided arguments.
13	*
14	* You can wrap your calls to a signature provider with the
15	* {@see SignatureProvider::resolve} function to ensure that a signature object
16	* is created. If a signature object is not created, then the resolve()
17	* function will throw a {@see Aws\Exception\UnresolvedSignatureException}.
18	*
19	* use Aws\Signature\SignatureProvider;
20	* $provider = SignatureProvider::defaultProvider();
21	* // Returns a SignatureInterface or NULL.
22	* $signer = $provider('v4', 's3', 'us-west-2');
23	* // Returns a SignatureInterface or throws.
24	* $signer = SignatureProvider::resolve($provider, 'no', 's3', 'foo');
25	*
26	* You can compose multiple providers into a single provider using
27	* {@see Aws\or_chain}. This function accepts providers as arguments and
28	* returns a new function that will invoke each provider until a non-null value
29	* is returned.
30	*
31	* $a = SignatureProvider::defaultProvider();
32	* $b = function ($version, $service, $region) {
33	* if ($version === 'foo') {
34	* return new MyFooSignature();
35	* }
36	* };
37	* $c = \Aws\or_chain($a, $b);
38	* $signer = $c('v4', 'abc', '123'); // $a handles this.
39	* $signer = $c('foo', 'abc', '123'); // $b handles this.
40	* $nullValue = $c('???', 'abc', '123'); // Neither can handle this.
41	*/
42	class SignatureProvider
43	{
44	private static $s3v4SignedServices = ['s3' => \true, 's3control' => \true, 's3-outposts' => \true, 's3-object-lambda' => \true, 's3express' => \true];
45	/**
46	* Resolves and signature provider and ensures a non-null return value.
47	*
48	* @param callable $provider Provider function to invoke.
49	* @param string $version Signature version.
50	* @param string $service Service name.
51	* @param string $region Region name.
52	*
53	* @return SignatureInterface
54	* @throws UnresolvedSignatureException
55	*/
56	public static function resolve(callable $provider, $version, $service, $region)
57	{
58	$result = $provider($version, $service, $region);
59	if ($result instanceof SignatureInterface \|\| $result instanceof BearerTokenAuthorization) {
60	return $result;
61	}
62	throw new UnresolvedSignatureException("Unable to resolve a signature for {$version}/{$service}/{$region}.\n" . "Valid signature versions include v4 and anonymous.");
63	}
64	/**
65	* Default SDK signature provider.
66	*
67	* @return callable
68	*/
69	public static function defaultProvider()
70	{
71	return self::memoize(self::version());
72	}
73	/**
74	* Creates a signature provider that caches previously created signature
75	* objects. The computed cache key is the concatenation of the version,
76	* service, and region.
77	*
78	* @param callable $provider Signature provider to wrap.
79	*
80	* @return callable
81	*/
82	public static function memoize(callable $provider)
83	{
84	$cache = [];
85	return function ($version, $service, $region) use(&$cache, $provider) {
86	$key = "({$version})({$service})({$region})";
87	if (!isset($cache[$key])) {
88	$cache[$key] = $provider($version, $service, $region);
89	}
90	return $cache[$key];
91	};
92	}
93	/**
94	* Creates signature objects from known signature versions.
95	*
96	* This provider currently recognizes the following signature versions:
97	*
98	* - v4: Signature version 4.
99	* - anonymous: Does not sign requests.
100	*
101	* @return callable
102	*/
103	public static function version()
104	{
105	return function ($version, $service, $region) {
106	switch ($version) {
107	case 'v4-s3express':
108	return new S3ExpressSignature($service, $region);
109	case 's3v4':
110	case 'v4':
111	return !empty(self::$s3v4SignedServices[$service]) ? new S3SignatureV4($service, $region) : new SignatureV4($service, $region);
112	case 'v4a':
113	return !empty(self::$s3v4SignedServices[$service]) ? new S3SignatureV4($service, $region, ['use_v4a' => \true]) : new SignatureV4($service, $region, ['use_v4a' => \true]);
114	case 'v4-unsigned-body':
115	return !empty(self::$s3v4SignedServices[$service]) ? new S3SignatureV4($service, $region, ['unsigned-body' => 'true']) : new SignatureV4($service, $region, ['unsigned-body' => 'true']);
116	case 'bearer':
117	return new BearerTokenAuthorization();
118	case 'anonymous':
119	return new AnonymousSignature();
120	default:
121	return null;
122	}
123	};
124	}
125	}
126