@Override
    public List<HostSpec> prepare(ClusterSpec cluster, Capacity capacity, ProvisionLogger logger) {
        List<HostSpec> hosts = new ArrayList<>();
        hosts.add(new HostSpec(host.hostname(),
                               NodeResources.unspecified(), NodeResources.unspecified(), NodeResources.unspecified(),
                               ClusterMembership.from(cluster.with(Optional.of(ClusterSpec.Group.from(0))), counter++),
                               Optional.empty(), Optional.empty(), Optional.empty()));
        return hosts;
    }
A host provisioner used when there is no hosts.xml file (using localhost as the only host)
No state in this provisioner, i.e. it does not know anything about the active
application if one exists.

@author hmusum
config-model/src/main/java/com/yahoo/config/model/provision/SingleNodeProvisioner.java