I just installed the controller via Helm, I can list the helm packages via helm list, but is it possible to list all the controllers running in the cluster via kubectl or api-query?
If you mean replication controller then you can list them by kubectl:
kubectl get replicationcontroller -n my-namespaceOr list them all from all the namespaces:
kubectl get rc --all-namespacesAnd you can also use API:
curl http://localhost:8080/api/v1/replicationcontrollersUpdate: You can list other controller types like replicaset (rs), deployment (deploy), statefulset, daemonset (ds) and job in the same way.