As of kubernetes 1.8 installation method is not valid as:
"ThirdPartyResource is deprecated as of Kubernetes 1.7 and has been removed in version 1.8 in accordance with the deprecation policy for beta features."
Monasca deployment will fail with:
helm install monasca/monasca --name monasca --namespace monitoring
Error: error validating "": error validating data: couldn't find type: v1beta1.ThirdPartyResource
due to API does not longer exists.
Ref:
https://kubernetes.io/docs/tasks/access-kubernetes-api/extend-api-third-party-resource/