Terraform configuration for heapster to deploy on kubernetes cluster is failing with error:

Blocks of type "selector" are not expected here. Did you mean to define
argument "selector"? If so, use the equals sign to assign it a value.

Resource configuration is:

resource "kubernetes_service" "service"{
    metadata {
        name="monitoring-influxdb"
        namespace="kube-system"
    }

    spec {
        selector {
            k8s-app="influxdb"
        }

        port{
            port=8086
            target_port=8086
        }
    }
}