Merge pull request #8727 from MrPetovan/task/8676-ap-attachments

[friendica.git] / src / Util / Network.php

diff --git a/src/Util/Network.php b/src/Util/Network.php
index e2cfc3e849a69952d1d5e13a8f29eba2674f6305..6b73369d32a72dba3187741dcc0c97869aa0da8f 100644 (file)
--- a/src/Util/Network.php
+++ b/src/Util/Network.php
@@ -1,7 +1,24 @@
 <?php
 /**
- * @file src/Util/Network.php
+ * @copyright Copyright (C) 2020, Friendica
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
  */
+
 namespace Friendica\Util;
 
 use DOMDocument;
@@ -870,4 +887,69 @@ class Network
 
                return $url;
        }
+
+       /**
+        * Adds query string parameters to the provided URI. Replace the value of existing keys.
+        *
+        * @param string $path
+        * @param array  $additionalParams Associative array of parameters
+        * @return string
+        */
+       public static function appendQueryParam(string $path, array $additionalParams)
+       {
+               $parsed = parse_url($path);
+
+               $params = [];
+               if (!empty($parsed['query'])) {
+                       parse_str($parsed['query'], $params);
+               }
+
+               $params = array_merge($params, $additionalParams);
+
+               $parsed['query'] = http_build_query($params);
+
+               return self::unparseURL($parsed);
+       }
+
+       /**
+        * Generates ETag and Last-Modified response headers and checks them against
+        * If-None-Match and If-Modified-Since request headers if present.
+        *
+        * Blocking function, sends 304 headers and exits if check passes.
+        *
+        * @param string $etag          The page etag
+        * @param string $last_modified The page last modification UTC date
+        * @throws \Exception
+        */
+       public static function checkEtagModified(string $etag, string $last_modified)
+       {
+               $last_modified = DateTimeFormat::utc($last_modified, 'D, d M Y H:i:s') . ' GMT';
+
+               /**
+                * @see http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26
+                */
+               $if_none_match     = filter_input(INPUT_SERVER, 'HTTP_IF_NONE_MATCH');
+               $if_modified_since = filter_input(INPUT_SERVER, 'HTTP_IF_MODIFIED_SINCE');
+               $flag_not_modified = null;
+               if ($if_none_match) {
+                       $result = [];
+                       preg_match('/^(?:W\/")?([^"]+)"?$/i', $etag, $result);
+                       $etagTrimmed = $result[1];
+                       // Lazy exact ETag match, could check weak/strong ETags
+                       $flag_not_modified = $if_none_match == '*' || strpos($if_none_match, $etagTrimmed) !== false;
+               }
+
+               if ($if_modified_since && (!$if_none_match || $flag_not_modified)) {
+                       // Lazy exact Last-Modified match, could check If-Modified-Since validity
+                       $flag_not_modified = $if_modified_since == $last_modified;
+               }
+
+               header('Etag: ' . $etag);
+               header('Last-Modified: ' . $last_modified);
+
+               if ($flag_not_modified) {
+                       header("HTTP/1.1 304 Not Modified");
+                       exit;
+               }
+       }
 }