External processing

Use the Envoy external processing (ExtProc) filter to connect an external gRPC processing server to the Envoy filter chain. The external service can manipulate headers, body, and trailers of a request or response before it is forwarded to an upstream or downstream service. The request or response can also be terminated at any given time.

• About external processing: Learn about what external processing is, how it works, and how to enable it in Gloo Gateway.

• Header manipulation: Walk through an example for how to manipulate request headers by using an ExtProc server.