fix(ns-api): improve dpireport details (#958)

When showing details of network traffic, do not
display hosts with 0 bytes of traffic

#900

packages/ns-api/files/ns.dpireport

@@ -205,6 +205,9 @@ def summary_v2(year=None, month=None, day=None, narrow_client=None, narrow_secti
             'traffic': raw_client_total_traffic
         })
 
+    # do not display empty values when seeing details
+    if narrow_section and narrow_value:
+        raw_clients = [client for client in raw_clients if client['traffic'] > 0]
     raw_clients.sort(key=lambda x: x['traffic'], reverse=True)
     final_clients = raw_clients[:limit]