[question] How to access `with` fields inside a hook

I'm using a hook to write the logs to graylog using GELF client ( "gopkg.in/Graylog2/go-gelf.v2/gelf")

it appears that there is no way to access with fields

like

log.With().Str("k","v).Logger().Info().Msg("some message")

I want to add the k as extra field (with its value as v) in GELF message.

is there a way we can do this?