In order to integrate services with Cloud Endpoints, Google provides the Extensible Service Proxy (ESP), a high-performance NGINX proxy that sits between application services and clients. The ESP can be run as a Docker container, installed as a Debian 8 package, or compiled directly from source code. As HTTP(S) and gRPC traffic passes through, it is monitored and controlled via the ESP using the Cloud Endpoints Services API.
Because the ESP is available as a Docker container, it can be run virtually anywhere. Common applications include running the ESP on a Compute Engine instance or as a sidecar for Kubernetes pods (including GKE). Really, the ESP can be used anywhere that supports Docker, including on-premises servers and ...
