Handle error responses from remote server more elegantly

htdocs/api/xmlrpc/lib.php

@@ -83,6 +83,18 @@ function get_public_key($uri, $application=null) {
     if (empty($raw)) {
         throw new XmlrpcClientException('CURL connection failed');
     }
+
+    $response_code        = curl_getinfo($ch, CURLINFO_HTTP_CODE);
+    $response_code_prefix = substr($response_code, 0, 1);
+
+    if ('2' != $response_code_prefix) {
+        if ('4' == $response_code_prefix) {
+            throw new XmlrpcClientException('Client error code: ', $response_code);
+        } elseif('5' == $response_code_prefix) {
+            throw new XmlrpcClientException('An error occurred at the remote server. Code: ', $response_code);
+        }
+    }
+
     $res = xmlrpc_decode($raw);
     curl_close($ch);