Apache Traffic Server (ATS) is a high performance, open-source, caching proxy server that is scalable and configurable. This project uses ATS as a Kubernetes(K8s) ingress
From high-level, the ingress controller talks to K8s' API and sets up watchers
on specific resources that are interesting to ATS. Then, the controller controls ATS by either(1) relay the information from K8s API to ATS, or (2) configure ATS directly.