hm, I changed it as you suggested. but the response is the same:
that is the response when the user is new:
json:"{}" txn:<start_ts:12570 commit_ts:12571 preds:"1-\000\000\000\000\000\000\000\000auth_id" preds:"1-\000\000\000\000\000\000\000\000dgraph.type" preds:"1-\000\000\000\000\000\000\000\000email" preds:"1-\000\000\000\000\000\000\000\000last_login_at" preds:"1-\000\000\000\000\000\000\000\000name" preds:"1-\000\000\000\000\000\000\000\000nationality" preds:"1-\000\000\000\000\000\000\000\000registered_at" preds:"1-\000\000\000\000\000\000\000\000surname" preds:"1-\000\000\000\000\000\000\000\000updated_at" > latency:<parsing_ns:202100 processing_ns:4059300 encoding_ns:11700 assign_timestamp_ns:1113400 total_ns:5766100 > metrics:<num_uids:<key:"" value:1 > num_uids:<key:"_total" value:12 > num_uids:<key:"auth_id" value:0 > num_uids:<key:"email" value:0 > num_uids:<key:"mutation_cost" value:10 > num_uids:<key:"uid" value:0 > num_uids:<key:"user" value:1 > > uids:<key:"secret_id_1" value:"0x2712" > hdrs:<key:"content-type" value:<value:"application/grpc" > > hdrs:<key:"dgraph-toucheduids" value:<value:"12" > >
and this is the response when the user tries again:
json:"{}" txn:<start_ts:12576 commit_ts:12577 > latency:<parsing_ns:188700 processing_ns:2645200 encoding_ns:16300 assign_timestamp_ns:774300 total_ns:3788000 > metrics:<num_uids:<key:"" value:1 > num_uids:<key:"_total" value:5 > num_uids:<key:"auth_id" value:1 > num_uids:<key:"email" value:1 > num_uids:<key:"mutation_cost" value:0 > num_uids:<key:"uid" value:1 > num_uids:<key:"user" value:1 > > hdrs:<key:"content-type" value:<value:"application/grpc" > > hdrs:<key:"dgraph-toucheduids" value:<value:"5" > >
so in both cases, JSON is empty.
but the map of UIDs is filled in case it was a new user. (so the upsert query didn’t stop the mutation)
btw. in your documentation: upsert example the upsert query is also empty.