How to get protobuf messsages from ic?

The ic-protobuf contains protobuf messages used by the Replica. But I don’t know how to get the protobuf messages like registry. does anyone can give me a example?

We’ve talked some about a protobuf library for motoko, but the general consensus has been to migrate toward candid and add candid interfaces for the few protobuf functions that are out there. I don’t understand the slowness in adding these endpoints, but hopefully they are coming soon. The big outstanding ones that I know about are:

-getting Block detail
-getting archive index

Ledger Archive
-getting Block detail

-getting the XDR ratio