cniConfigStr = strings.ReplaceAll(cniConfigStr, "__LOG_LEVEL__", vars.logLevel)
	cniConfigStr = strings.ReplaceAll(cniConfigStr, "__LOG_UDS_ADDRESS__", vars.logUDSAddress)
	cniConfigStr = strings.ReplaceAll(cniConfigStr, "__CNI_EVENT_ADDRESS__", vars.cniEventAddress)
	cniConfigStr = strings.ReplaceAll(cniConfigStr, "__KUBECONFIG_FILENAME__", vars.kubeconfigFilename)

	"k8s.io/apimachinery/pkg/types"
	"k8s.io/client-go/kubernetes"
)

// Use UUID of kube-system Namespace as unique identifier for cluster.
// (see https://docs.google.com/document/d/1F__vEKeI41P7PPUCMM9PVPYY34pyrvQI5rbTJVnS5c4)
func clusterUID(client kubernetes.Interface) (types.UID, error) {
	kubeSystem, err := client.CoreV1().Namespaces().Get(context.TODO(), "kube-system", metav1.GetOptions{})
	if err != nil {

	cniNetworkConfigName = "CNI_NETWORK_CONFIG"
	cniNetworkConfig     = `{
  "cniVersion": "0.3.1",
  "type": "istio-cni",
  "log_level": "info",
  "kubernetes": {
      "kubeconfig": "__KUBECONFIG_FILEPATH__",
      "cni_bin_dir": "/opt/cni/bin",
      "exclude_namespaces": [ "istio-system" ]
  }
}
`
)

func getEnv(key, fallback string) string {
	if value, ok := os.LookupEnv(key); ok {
		return value

	// CreateCNIConfigFile joins the MountedCNINetDir and KubeconfigFilename if __KUBECONFIG_FILEPATH__ was used
	kubeconfigFilename   = "/path/to/kubeconfig"
	cniNetworkConfigFile = "testdata/istio-cni.conf.template"
	cniNetworkConfig     = `{
  "cniVersion": "0.3.1",
  "name": "istio-cni",
  "type": "istio-cni",
  "log_level": "__LOG_LEVEL__",
  "kubernetes": {