fav_core is the core library of fav(A cli tool to download remote resources and keep a local state in protobuf).
fav_utils provides the utils for fav_cli, which now only support bilibili(Like Chinese Youtube). You can see it as a example for using this crate.
All you need is to define data structures with protobuf like this example.
And impl traits in fav_core like Res, Set, Sets, Status, Attr to defined resources, and AuthOps, SetOps, SetsOps to operate resources.
After that, many Ext method will be available for you to use, helping you batchly operating resource, getting subset of resource, and so on.
Examples can be find here.
To derive trait for code generated by protobuf, see example.