summaryrefslogtreecommitdiffstats
path: root/vendor/guzzlehttp/psr7/src/UriNormalizer.php
blob: f5c093c20aca50e95259ce5ad465d9727f264a0a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
<?php

namespace GuzzleHttp\Psr7;

use Psr\Http\Message\UriInterface;

/**
 * Provides methods to normalize and compare URIs.
 *
 * @author Tobias Schultze
 *
 * @link https://tools.ietf.org/html/rfc3986#section-6
 */
final class UriNormalizer
{
    /**
     * Default normalizations which only include the ones that preserve semantics.
     *
     * self::CAPITALIZE_PERCENT_ENCODING | self::DECODE_UNRESERVED_CHARACTERS | self::CONVERT_EMPTY_PATH |
     * self::REMOVE_DEFAULT_HOST | self::REMOVE_DEFAULT_PORT | self::REMOVE_DOT_SEGMENTS
     */
    const PRESERVING_NORMALIZATIONS = 63;

    /**
     * All letters within a percent-encoding triplet (e.g., "%3A") are case-insensitive, and should be capitalized.
     *
     * Example: http://example.org/a%c2%b1b → http://example.org/a%C2%B1b
     */
    const CAPITALIZE_PERCENT_ENCODING = 1;

    /**
     * Decodes percent-encoded octets of unreserved characters.
     *
     * For consistency, percent-encoded octets in the ranges of ALPHA (%41–%5A and %61–%7A), DIGIT (%30–%39),
     * hyphen (%2D), period (%2E), underscore (%5F), or tilde (%7E) should not be created by URI producers and,
     * when found in a URI, should be decoded to their corresponding unreserved characters by URI normalizers.
     *
     * Example: http://example.org/%7Eusern%61me/ → http://example.org/~username/
     */
    const DECODE_UNRESERVED_CHARACTERS = 2;

    /**
     * Converts the empty path to "/" for http and https URIs.
     *
     * Example: http://example.org → http://example.org/
     */
    const CONVERT_EMPTY_PATH = 4;

    /**
     * Removes the default host of the given URI scheme from the URI.
     *
     * Only the "file" scheme defines the default host "localhost".
     * All of `file:/myfile`, `file:///myfile`, and `file://localhost/myfile`
     * are equivalent according to RFC 3986. The first format is not accepted
     * by PHPs stream functions and thus already normalized implicitly to the
     * second format in the Uri class. See `GuzzleHttp\Psr7\Uri::composeComponents`.
     *
     * Example: file://localhost/myfile → file:///myfile
     */
    const REMOVE_DEFAULT_HOST = 8;

    /**
     * Removes the default port of the given URI scheme from the URI.
     *
     * Example: http://example.org:80/ → http://example.org/
     */
    const REMOVE_DEFAULT_PORT = 16;

    /**
     * Removes unnecessary dot-segments.
     *
     * Dot-segments in relative-path references are not removed as it would
     * change the semantics of the URI reference.
     *
     * Example: http://example.org/../a/b/../c/./d.html → http://example.org/a/c/d.html
     */
    const REMOVE_DOT_SEGMENTS = 32;

    /**
     * Paths which include two or more adjacent slashes are converted to one.
     *
     * Webservers usually ignore duplicate slashes and treat those URIs equivalent.
     * But in theory those URIs do not need to be equivalent. So this normalization
     * may change the semantics. Encoded slashes (%2F) are not removed.
     *
     * Example: http://example.org//foo///bar.html → http://example.org/foo/bar.html
     */
    const REMOVE_DUPLICATE_SLASHES = 64;

    /**
     * Sort query parameters with their values in alphabetical order.
     *
     * However, the order of parameters in a URI may be significant (this is not defined by the standard).
     * So this normalization is not safe and may change the semantics of the URI.
     *
     * Example: ?lang=en&article=fred → ?article=fred&lang=en
     *
     * Note: The sorting is neither locale nor Unicode aware (the URI query does not get decoded at all) as the
     * purpose is to be able to compare URIs in a reproducible way, not to have the params sorted perfectly.
     */
    const SORT_QUERY_PARAMETERS = 128;

    /**
     * Returns a normalized URI.
     *
     * The scheme and host component are already normalized to lowercase per PSR-7 UriInterface.
     * This methods adds additional normalizations that can be configured with the $flags parameter.
     *
     * PSR-7 UriInterface cannot distinguish between an empty component and a missing component as
     * getQuery(), getFragment() etc. always return a string. This means the URIs "/?#" and "/" are
     * treated equivalent which is not necessarily true according to RFC 3986. But that difference
     * is highly uncommon in reality. So this potential normalization is implied in PSR-7 as well.
     *
     * @param UriInterface $uri   The URI to normalize
     * @param int          $flags A bitmask of normalizations to apply, see constants
     *
     * @return UriInterface The normalized URI
     *
     * @link https://tools.ietf.org/html/rfc3986#section-6.2
     */
    public static function normalize(UriInterface $uri, $flags = self::PRESERVING_NORMALIZATIONS)
    {
        if ($flags & self::CAPITALIZE_PERCENT_ENCODING) {
            $uri = self::capitalizePercentEncoding($uri);
        }

        if ($flags & self::DECODE_UNRESERVED_CHARACTERS) {
            $uri = self::decodeUnreservedCharacters($uri);
        }

        if ($flags & self::CONVERT_EMPTY_PATH && $uri->getPath() === '' &&
            ($uri->getScheme() === 'http' || $uri->getScheme() === 'https')
        ) {
            $uri = $uri->withPath('/');
        }

        if ($flags & self::REMOVE_DEFAULT_HOST && $uri->getScheme() === 'file' && $uri->getHost() === 'localhost') {
            $uri = $uri->withHost('');
        }

        if ($flags & self::REMOVE_DEFAULT_PORT && $uri->getPort() !== null && Uri::isDefaultPort($uri)) {
            $uri = $uri->withPort(null);
        }

        if ($flags & self::REMOVE_DOT_SEGMENTS && !Uri::isRelativePathReference($uri)) {
            $uri = $uri->withPath(UriResolver::removeDotSegments($uri->getPath()));
        }

        if ($flags & self::REMOVE_DUPLICATE_SLASHES) {
            $uri = $uri->withPath(preg_replace('#//++#', '/', $uri->getPath()));
        }

        if ($flags & self::SORT_QUERY_PARAMETERS && $uri->getQuery() !== '') {
            $queryKeyValues = explode('&', $uri->getQuery());
            sort($queryKeyValues);
            $uri = $uri->withQuery(implode('&', $queryKeyValues));
        }

        return $uri;
    }

    /**
     * Whether two URIs can be considered equivalent.
     *
     * Both URIs are normalized automatically before comparison with the given $normalizations bitmask. The method also
     * accepts relative URI references and returns true when they are equivalent. This of course assumes they will be
     * resolved against the same base URI. If this is not the case, determination of equivalence or difference of
     * relative references does not mean anything.
     *
     * @param UriInterface $uri1           An URI to compare
     * @param UriInterface $uri2           An URI to compare
     * @param int          $normalizations A bitmask of normalizations to apply, see constants
     *
     * @return bool
     *
     * @link https://tools.ietf.org/html/rfc3986#section-6.1
     */
    public static function isEquivalent(UriInterface $uri1, UriInterface $uri2, $normalizations = self::PRESERVING_NORMALIZATIONS)
    {
        return (string) self::normalize($uri1, $normalizations) === (string) self::normalize($uri2, $normalizations);
    }

    private static function capitalizePercentEncoding(UriInterface $uri)
    {
        $regex = '/(?:%[A-Fa-f0-9]{2})++/';

        $callback = function (array $match) {
            return strtoupper($match[0]);
        };

        return
            $uri->withPath(
                preg_replace_callback($regex, $callback, $uri->getPath())
            )->withQuery(
                preg_replace_callback($regex, $callback, $uri->getQuery())
            );
    }

    private static function decodeUnreservedCharacters(UriInterface $uri)
    {
        $regex = '/%(?:2D|2E|5F|7E|3[0-9]|[46][1-9A-F]|[57][0-9A])/i';

        $callback = function (array $match) {
            return rawurldecode($match[0]);
        };

        return
            $uri->withPath(
                preg_replace_callback($regex, $callback, $uri->getPath())
            )->withQuery(
                preg_replace_callback($regex, $callback, $uri->getQuery())
            );
    }

    private function __construct()
    {
        // cannot be instantiated
    }
}