+/**
+ * Removes undesired query parameters and fragments
+ *
+ * @param string url Url to be cleaned
+ *
+ * @return string the string representation of this URL after cleanup
+ */
+function cleanup_url($url)
+{
+ $obj_url = new Url($url);
+ return $obj_url->cleanup();
+}
+
+/**
+ * Get URL scheme.
+ *
+ * @param string url Url for which the scheme is requested
+ *
+ * @return mixed the URL scheme or false if none is provided.
+ */
+function get_url_scheme($url)
+{
+ $obj_url = new Url($url);
+ return $obj_url->getScheme();
+}
+
+/**
+ * Adds a trailing slash at the end of URL if necessary.
+ *
+ * @param string $url URL to check/edit.
+ *
+ * @return string $url URL with a end trailing slash.
+ */
+function add_trailing_slash($url)
+{
+ return $url . (!endsWith($url, '/') ? '/' : '');
+}
+
+/**
+ * Replace not whitelisted protocols by 'http://' from given URL.
+ *
+ * @param string $url URL to clean
+ * @param array $protocols List of allowed protocols (aside from http(s)).
+ *
+ * @return string URL with allowed protocol
+ */
+function whitelist_protocols($url, $protocols)
+{
+ if (startsWith($url, '?') || startsWith($url, '/')) {
+ return $url;
+ }
+ $protocols = array_merge(['http', 'https'], $protocols);
+ $protocol = preg_match('#^(\w+):/?/?#', $url, $match);
+ // Protocol not allowed: we remove it and replace it with http
+ if ($protocol === 1 && ! in_array($match[1], $protocols)) {
+ $url = str_replace($match[0], 'http://', $url);
+ } else if ($protocol !== 1) {
+ $url = 'http://' . $url;
+ }
+ return $url;
+}
+