How to visualize real-time datasource in Superset when using Kafka Indexing service for Druid?

How to visualize real-time datasource in Superset when using Kafka Indexing service for Druid?

I was test visualizing the realtime datasource in superset. Now, when running Kafka Indexing service for Druid, I can now query data from Druid by JSON query in the command line but I can not find the realtime datasource in superset, even after I refresh the matadata for datasources. Does anyone know how can I see the datasource that created by the Kafka-Indexing Service in Superset?

Really appreciate.