+ $owner = User::getOwnerDataById($uid);
+
+ if (!$owner) {
+ return;
+ }
+
+ // Header data that is about to be signed.
+ $host = parse_url($request, PHP_URL_HOST);
+ $path = parse_url($request, PHP_URL_PATH);
+ $date = DateTimeFormat::utcNow(DateTimeFormat::HTTP);
+
+ $headers = ['Date: ' . $date, 'Host: ' . $host];
+
+ $signed_data = "(request-target): get " . $path . "\ndate: ". $date . "\nhost: " . $host;
+
+ $signature = base64_encode(Crypto::rsaSign($signed_data, $owner['uprvkey'], 'sha256'));
+
+ $headers[] = 'Signature: keyId="' . $owner['url'] . '#main-key' . '",algorithm="rsa-sha256",headers="(request-target) date host",signature="' . $signature . '"';
+
+ $headers[] = 'Accept: application/activity+json, application/ld+json';