[Rspamd] Add metadata exporter for unauthed mail

data/conf/rspamd/local.d/metadata_exporter.conf

@@ -12,8 +12,31 @@ rules {
 		selector = "ratelimited";
 		formatter = "json";
 	}
+  UNAUTHMAIL {
+    backend = "http";
+    url = "http://nginx:9081/pushover.php";
+    selector = "unauth_mail";
+    # Only return msgid, do not parse the full message
+    formatter = "msgid";
+    meta_headers = true;
+  }
 }
+
 custom_select {
+  unauth_mail = <<EOD
+return function(task)
+  local action = task:get_metric_action('default')
+  if task:has_symbol('NO_LOG_STAT') or (action == 'reject' or action == 'add header' or action == 'rewrite subject') then
+    return false
+  else
+    local uname = task:get_user()
+    if not uname then
+      return true
+    end
+    return false
+  end
+end
+EOD;
   ratelimited = <<EOD
 return function(task)
   local ratelimited = task:get_symbol("RATELIMITED")
@@ -33,3 +56,12 @@ return function(task)
 end
 EOD;
 }
+
+custom_format {
+  msgid = <<EOD
+return function(task)
+  return task:get_message_id()
+end
+EOD;
+}
+