bring some Zot6 libraries and interfaces to red/hubzilla

Zotlabs/Lib/Webfinger.php

@@ -0,0 +1,109 @@
+<?php
+
+namespace Zotlabs\Lib;
+
+/**
+ * @brief Fetch and return a webfinger for a resource
+ *
+ * @param string $resource - The resource
+ * @return boolean|string false or associative array from result JSON
+ */
+
+class Webfinger {
+
+	static private $server   = EMPTY_STR;
+	static private $resource = EMPTY_STR;
+
+	static function exec($resource) {
+
+		if(! $resource) {
+			return false;
+		}
+
+		self::parse_resource($resource);
+
+		if(! ( self::$server && self::$resource)) {
+			return false;
+		}
+
+		if(! check_siteallowed(self::$server)) {
+			logger('blacklisted: ' . self::$server);
+			return false;
+		}
+
+		btlogger('fetching resource: ' . self::$resource . ' from ' . self::$server, LOGGER_DEBUG, LOG_INFO);
+
+		$url = 'https://' . self::$server . '/.well-known/webfinger?f=&resource=' . self::$resource ;
+
+		$counter = 0;
+		$s = z_fetch_url($url, false, $counter, [ 'headers' => [ 'Accept: application/jrd+json, */*' ] ]);
+
+		if($s['success']) {
+			$j = json_decode($s['body'], true);
+			return($j);
+		}
+
+		return false;
+	}
+
+	static function parse_resource($resource) {
+
+		self::$resource = urlencode($resource);
+
+		if(strpos($resource,'http') === 0) {
+			$m = parse_url($resource);
+			if($m) {
+				if($m['scheme'] !== 'https') {
+					return false;
+				}
+				self::$server = $m['host'] . (($m['port']) ? ':' . $m['port'] : '');
+			}
+			else {
+				return false;
+			}
+		}
+		elseif(strpos($resource,'tag:') === 0) {
+			$arr = explode(':',$resource); // split the tag
+			$h = explode(',',$arr[1]); // split the host,date
+			self::$server = $h[0];
+		}
+		else {
+			$x = explode('@',$resource);
+			$username = $x[0];
+			if(count($x) > 1) {
+				self::$server = $x[1];
+			}
+			else {
+				return false;
+			}
+			if(strpos($resource,'acct:') !== 0) {
+				self::$resource = urlencode('acct:' . $resource);
+			}
+		}
+
+	}
+
+	/**
+	 * @brief fetch a webfinger resource and return a zot6 discovery url if present
+	 *
+	 */ 
+
+	static function zot_url($resource) {
+
+		$arr = self::exec($resource);
+
+		if(is_array($arr) && array_key_exists('links',$arr)) {
+			foreach($arr['links'] as $link) {
+				if(array_key_exists('rel',$link) && $link['rel'] === PROTOCOL_ZOT6) {
+					if(array_key_exists('href',$link) && $link['href'] !== EMPTY_STR) {
+						return $link['href'];
+					}
+				}
+			}
+		}
+		return false;
+	}
+
+
+
+}