<?php
/*
* This file is part of the JsonSchema package.
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace JsonSchema\Uri;
use JsonSchema\Exception\UriResolverException;
use JsonSchema\UriResolverInterface;
/**
* Resolves JSON Schema URIs
*
* @author Sander Coolen <sander@jibber.nl>
*/
class UriResolver implements UriResolverInterface
{
/**
* Parses a URI into five main components
*
* @param string $uri
*
* @return array
*/
public function parse($uri)
{
preg_match('|^(([^:/?#]+):)?(//([^/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?|', $uri, $match);
$components = array();
if (5 < count($match)) {
$components = array(
'scheme' => $match[2],
'authority' => $match[4],
'path' => $match[5]
);
}
if (7 < count($match)) {
$components['query'] = $match[7];
}
if (9 < count($match)) {
$components['fragment'] = $match[9];
}
return $components;
}
/**
* Builds a URI based on n array with the main components
*
* @param array $components
*
* @return string
*/
public function generate(array $components)
{
$uri = $components['scheme'] . '://'
. $components['authority']
. $components['path'];
if (array_key_exists('query', $components) && strlen($components['query'])) {
$uri .= '?' . $components['query'];
}
if (array_key_exists('fragment', $components)) {
$uri .= '#' . $components['fragment'];
}
return $uri;
}
/**
* {@inheritdoc}
*/
public function resolve($uri, $baseUri = null)
{
// treat non-uri base as local file path
if (
!is_null($baseUri) &&
!filter_var($baseUri, \FILTER_VALIDATE_URL) &&
!preg_match('|^[^/]+://|u', $baseUri)
) {
if (is_file($baseUri)) {
$baseUri = 'file://' . realpath($baseUri);
} elseif (is_dir($baseUri)) {
$baseUri = 'file://' . realpath($baseUri) . '/';
} else {
$baseUri = 'file://' . getcwd() . '/' . $baseUri;
}
}
if ($uri == '') {
return $baseUri;
}
$components = $this->parse($uri);
$path = $components['path'];
if (!empty($components['scheme'])) {
return $uri;
}
$baseComponents = $this->parse($baseUri);
$basePath = $baseComponents['path'];
$baseComponents['path'] = self::combineRelativePathWithBasePath($path, $basePath);
if (isset($components['fragment'])) {
$baseComponents['fragment'] = $components['fragment'];
}
return $this->generate($baseComponents);
}
/**
* Tries to glue a relative path onto an absolute one
*
* @param string $relativePath
* @param string $basePath
*
* @throws UriResolverException
*
* @return string Merged path
*/
public static function combineRelativePathWithBasePath($relativePath, $basePath)
{
$relativePath = self::normalizePath($relativePath);
if ($relativePath == '') {
return $basePath;
}
if ($relativePath[0] == '/') {
return $relativePath;
}
$basePathSegments = explode('/', $basePath);
preg_match('|^/?(\.\./(?:\./)*)*|', $relativePath, $match);
$numLevelUp = strlen($match[0]) /3 + 1;
if ($numLevelUp >= count($basePathSegments)) {
throw new UriResolverException(sprintf("Unable to resolve URI '%s' from base '%s'", $relativePath, $basePath));
}
$basePathSegments = array_slice($basePathSegments, 0, -$numLevelUp);
$path = preg_replace('|^/?(\.\./(\./)*)*|', '', $relativePath);
return implode('/', $basePathSegments) . '/' . $path;
}
/**
* Normalizes a URI path component by removing dot-slash and double slashes
*
* @param string $path
*
* @return string
*/
private static function normalizePath($path)
{
$path = preg_replace('|((?<!\.)\./)*|', '', $path);
$path = preg_replace('|//|', '/', $path);
return $path;
}
/**
* @param string $uri
*
* @return bool
*/
public function isValid($uri)
{
$components = $this->parse($uri);
return !empty($components);
}
}