The CloudStack backend response for listClustersMetrics "command" has changed its JSON structure, but the cloudstack-go wrapper is still parsing the old field (hostmetrics).
This results in host metrics being returned as null in the Go SDK response.
API: listClustersMetrics (command)
Client: github.com/apache/cloudstack-go/v2
Key change:
The backend now returns metrics under the field host, not hostmetrics.