The Stackable operator for Druid publishes a concepts:service_discovery.adoc with the following properties, where simple-derby-druid represents the name and stackable the namespace of the cluster:
DRUID_AVATICA_JDBC
Contains the connection string for the Avatica JDBC driver to connect to the router:
jdbc:avatica:remote:url=http://simple-derby-druid-router.stackable.svc.cluster.local:8888/druid/v2/sql/avatica/
DRUID_SQLALCHEMY
Contains the connection string for the python SQLAlchemy toolkit:
druid://simple-derby-druid-router.stackable.svc.cluster.local:8888/druid/v2/sql
DRUID_ROUTER
Contains the connection string for the Druid router:
simple-derby-druid-router.stackable.svc.cluster.local:8888