code: func setHostIPOnPodSpec(podSpec *v1.PodSpec) {
  	envVar := v1.EnvVar{
  		Name: "HOST_IP",
  		ValueFrom: &v1.EnvVarSource{
  			FieldRef: &v1.ObjectFieldSelector{
  				FieldPath: "status.hostIP",
  			},
  		},
  	}
  
  	podSpec.Containers[0].Env = append(podSpec.Containers[0].Env, envVar)
  
  	for i := range podSpec.Containers[0].Command {
  		if strings.Contains(podSpec.Containers[0].Command[i], "advertise-address") {
  			podSpec.Containers[0].Command[i] = "--advertise-address=$(HOST_IP)"
  		}
  	}
  }
docs: // setHostIPOnPodSpec sets the environment variable HOST_IP using downward API