This incredibly simple script provides a HTTP server used to forward the request to one or more servers. For this you need to provide a DNS name in the env variable TARGET_HOSTS_DNS_NAME. For each ip address to which this hostname resolves, this script issues a request on the port defined in TARGET_HOSTS_PORT and the given method and path from the original request.
Use case for this is to forward a http trigger to all instances of a deployment in a kubernetes cluster in parallel. The idea is to use a headless service for this case to retrieve all pods ip addresses by querying the hostname of this headless service.