mongodb: 
    read_preference: "secondary"
    read_preference_tags: 
      - storage: "SSD"

Our configuration looks like this. It works with mgo.
We switched to mongo-go-driver and found all the queries went to the primary.
But the driver threw exception if we intended to use a non-existed read preference tags.

Topology:
go client -> mongos -> a 3.2 sharded cluster