admin api: add compatibility from v1/ to v2/

src/api/router_macros.rs

@@ -165,8 +165,8 @@ macro_rules! router_match {
             .map_err(|_| Error::bad_request("Failed to parse query parameter"))?
     }};
     (@@parse_param $query:expr, parse_default($default:expr), $param:ident) => {{
-        // extract and parse mandatory query parameter
-        // both missing and un-parseable parameters are reported as errors
+        // extract and parse optional query parameter
+        // using provided value as default if paramter is missing
         $query.$param.take().map(|x| x
             .parse()
             .map_err(|_| Error::bad_request("Failed to parse query parameter")))