Returns a string representation of the node health

        @returns: GREEN if fully connected, YELLOW if partially connected,
                  RED if not connected

def _calculate_health(self):
        """Returns a string representation of the node health

        @returns: GREEN if fully connected, YELLOW if partially connected,
                  RED if not connected
        """
        if self.redis_connected and self.kafka_connected:
            return "GREEN"
        elif self.redis_connected or self.kafka_connected:
            return "YELLOW"
        else:
            return "RED"