| 
<?phpnamespace Aws\CloudFront;
 
 use GuzzleHttp\Psr7;
 use GuzzleHttp\Psr7\Uri;
 use Psr\Http\Message\UriInterface;
 
 /**
 * Creates signed URLs for Amazon CloudFront resources.
 */
 class UrlSigner
 {
 private $signer;
 
 /**
 * @param $keyPairId  string ID of the key pair
 * @param $privateKey string Path to the private key used for signing
 *
 * @throws \RuntimeException if the openssl extension is missing
 * @throws \InvalidArgumentException if the private key cannot be found.
 */
 public function __construct($keyPairId, $privateKey)
 {
 $this->signer = new Signer($keyPairId, $privateKey);
 }
 
 /**
 * Create a signed Amazon CloudFront URL.
 *
 * Keep in mind that URLs meant for use in media/flash players may have
 * different requirements for URL formats (e.g. some require that the
 * extension be removed, some require the file name to be prefixed
 * - mp4:<path>, some require you to add "/cfx/st" into your URL).
 *
 * @param string              $url     URL to sign (can include query
 *                                     string string and wildcards)
 * @param string|integer|null $expires UTC Unix timestamp used when signing
 *                                     with a canned policy. Not required
 *                                     when passing a custom $policy.
 * @param string              $policy  JSON policy. Use this option when
 *                                     creating a signed URL for a custom
 *                                     policy.
 *
 * @return string The file URL with authentication parameters
 * @throws \InvalidArgumentException if the URL provided is invalid
 * @link http://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/WorkingWithStreamingDistributions.html
 */
 public function getSignedUrl($url, $expires = null, $policy = null)
 {
 // Determine the scheme of the url
 $urlSections = explode('://', $url);
 
 if (count($urlSections) < 2) {
 throw new \InvalidArgumentException("Invalid URL: {$url}");
 }
 
 // Get the real scheme by removing wildcards from the scheme
 $scheme = str_replace('*', '', $urlSections[0]);
 $uri = new Uri($scheme . '://' . $urlSections[1]);
 $query = Psr7\parse_query($uri->getQuery(), PHP_QUERY_RFC3986);
 $signature = $this->signer->getSignature(
 $this->createResource($scheme, (string) $uri),
 $expires,
 $policy
 );
 $uri = $uri->withQuery(
 http_build_query($query + $signature, null, '&', PHP_QUERY_RFC3986)
 );
 
 return $scheme === 'rtmp'
 ? $this->createRtmpUrl($uri)
 : (string) $uri;
 }
 
 private function createRtmpUrl(UriInterface $uri)
 {
 // Use a relative URL when creating Flash player URLs
 $result = ltrim($uri->getPath(), '/');
 
 if ($query = $uri->getQuery()) {
 $result .= '?' . $query;
 }
 
 return $result;
 }
 
 /**
 * @param $scheme
 * @param $url
 *
 * @return string
 */
 private function createResource($scheme, $url)
 {
 switch ($scheme) {
 case 'http':
 case 'http*':
 case 'https':
 return $url;
 case 'rtmp':
 $parts = parse_url($url);
 $pathParts = pathinfo($parts['path']);
 $resource = ltrim(
 $pathParts['dirname'] . '/' . $pathParts['basename'],
 '/'
 );
 
 // Add a query string if present.
 if (isset($parts['query'])) {
 $resource .= "?{$parts['query']}";
 }
 
 return $resource;
 }
 
 throw new \InvalidArgumentException("Invalid URI scheme: {$scheme}. "
 . "Scheme must be one of: http, https, or rtmp");
 }
 }
 
 |