2 namespace GuzzleHttp\Psr7;
4 use Psr\Http\Message\UriInterface;
7 * Resolves a URI reference in the context of a base URI and the opposite way.
9 * @author Tobias Schultze
11 * @link https://tools.ietf.org/html/rfc3986#section-5
13 final class UriResolver
16 * Removes dot segments from a path and returns the new path.
21 * @link http://tools.ietf.org/html/rfc3986#section-5.2.4
23 public static function removeDotSegments($path)
25 if ($path === '' || $path === '/') {
30 $segments = explode('/', $path);
31 foreach ($segments as $segment) {
32 if ($segment === '..') {
34 } elseif ($segment !== '.') {
35 $results[] = $segment;
39 $newPath = implode('/', $results);
41 if ($path[0] === '/' && (!isset($newPath[0]) || $newPath[0] !== '/')) {
42 // Re-add the leading slash if necessary for cases like "/.."
43 $newPath = '/' . $newPath;
44 } elseif ($newPath !== '' && ($segment === '.' || $segment === '..')) {
45 // Add the trailing slash if necessary
46 // If newPath is not empty, then $segment must be set and is the last segment from the foreach
54 * Converts the relative URI into a new URI that is resolved against the base URI.
56 * @param UriInterface $base Base URI
57 * @param UriInterface $rel Relative URI
59 * @return UriInterface
60 * @link http://tools.ietf.org/html/rfc3986#section-5.2
62 public static function resolve(UriInterface $base, UriInterface $rel)
64 if ((string) $rel === '') {
65 // we can simply return the same base URI instance for this same-document reference
69 if ($rel->getScheme() != '') {
70 return $rel->withPath(self::removeDotSegments($rel->getPath()));
73 if ($rel->getAuthority() != '') {
74 $targetAuthority = $rel->getAuthority();
75 $targetPath = self::removeDotSegments($rel->getPath());
76 $targetQuery = $rel->getQuery();
78 $targetAuthority = $base->getAuthority();
79 if ($rel->getPath() === '') {
80 $targetPath = $base->getPath();
81 $targetQuery = $rel->getQuery() != '' ? $rel->getQuery() : $base->getQuery();
83 if ($rel->getPath()[0] === '/') {
84 $targetPath = $rel->getPath();
86 if ($targetAuthority != '' && $base->getPath() === '') {
87 $targetPath = '/' . $rel->getPath();
89 $lastSlashPos = strrpos($base->getPath(), '/');
90 if ($lastSlashPos === false) {
91 $targetPath = $rel->getPath();
93 $targetPath = substr($base->getPath(), 0, $lastSlashPos + 1) . $rel->getPath();
97 $targetPath = self::removeDotSegments($targetPath);
98 $targetQuery = $rel->getQuery();
102 return new Uri(Uri::composeComponents(
112 * Returns the target URI as a relative reference from the base URI.
114 * This method is the counterpart to resolve():
116 * (string) $target === (string) UriResolver::resolve($base, UriResolver::relativize($base, $target))
118 * One use-case is to use the current request URI as base URI and then generate relative links in your documents
119 * to reduce the document size or offer self-contained downloadable document archives.
121 * $base = new Uri('http://example.com/a/b/');
122 * echo UriResolver::relativize($base, new Uri('http://example.com/a/b/c')); // prints 'c'.
123 * echo UriResolver::relativize($base, new Uri('http://example.com/a/x/y')); // prints '../x/y'.
124 * echo UriResolver::relativize($base, new Uri('http://example.com/a/b/?q')); // prints '?q'.
125 * echo UriResolver::relativize($base, new Uri('http://example.org/a/b/')); // prints '//example.org/a/b/'.
127 * This method also accepts a target that is already relative and will try to relativize it further. Only a
128 * relative-path reference will be returned as-is.
130 * echo UriResolver::relativize($base, new Uri('/a/b/c')); // prints 'c' as well
132 * @param UriInterface $base Base URI
133 * @param UriInterface $target Target URI
135 * @return UriInterface The relative URI reference
137 public static function relativize(UriInterface $base, UriInterface $target)
139 if ($target->getScheme() !== '' &&
140 ($base->getScheme() !== $target->getScheme() || $target->getAuthority() === '' && $base->getAuthority() !== '')
145 if (Uri::isRelativePathReference($target)) {
146 // As the target is already highly relative we return it as-is. It would be possible to resolve
147 // the target with `$target = self::resolve($base, $target);` and then try make it more relative
148 // by removing a duplicate query. But let's not do that automatically.
152 if ($target->getAuthority() !== '' && $base->getAuthority() !== $target->getAuthority()) {
153 return $target->withScheme('');
156 // We must remove the path before removing the authority because if the path starts with two slashes, the URI
157 // would turn invalid. And we also cannot set a relative path before removing the authority, as that is also
159 $emptyPathUri = $target->withScheme('')->withPath('')->withUserInfo('')->withPort(null)->withHost('');
161 if ($base->getPath() !== $target->getPath()) {
162 return $emptyPathUri->withPath(self::getRelativePath($base, $target));
165 if ($base->getQuery() === $target->getQuery()) {
166 // Only the target fragment is left. And it must be returned even if base and target fragment are the same.
167 return $emptyPathUri->withQuery('');
170 // If the base URI has a query but the target has none, we cannot return an empty path reference as it would
171 // inherit the base query component when resolving.
172 if ($target->getQuery() === '') {
173 $segments = explode('/', $target->getPath());
174 $lastSegment = end($segments);
176 return $emptyPathUri->withPath($lastSegment === '' ? './' : $lastSegment);
179 return $emptyPathUri;
182 private static function getRelativePath(UriInterface $base, UriInterface $target)
184 $sourceSegments = explode('/', $base->getPath());
185 $targetSegments = explode('/', $target->getPath());
186 array_pop($sourceSegments);
187 $targetLastSegment = array_pop($targetSegments);
188 foreach ($sourceSegments as $i => $segment) {
189 if (isset($targetSegments[$i]) && $segment === $targetSegments[$i]) {
190 unset($sourceSegments[$i], $targetSegments[$i]);
195 $targetSegments[] = $targetLastSegment;
196 $relativePath = str_repeat('../', count($sourceSegments)) . implode('/', $targetSegments);
198 // A reference to am empty last segment or an empty first sub-segment must be prefixed with "./".
199 // This also applies to a segment with a colon character (e.g., "file:colon") that cannot be used
200 // as the first segment of a relative-path reference, as it would be mistaken for a scheme name.
201 if ('' === $relativePath || false !== strpos(explode('/', $relativePath, 2)[0], ':')) {
202 $relativePath = "./$relativePath";
203 } elseif ('/' === $relativePath[0]) {
204 if ($base->getAuthority() != '' && $base->getPath() === '') {
205 // In this case an extra slash is added by resolve() automatically. So we must not add one here.
206 $relativePath = ".$relativePath";
208 $relativePath = "./$relativePath";
212 return $relativePath;
215 private function __construct()
217 // cannot be instantiated