ext_authz example

apiVersion: networking.istio.io/v1alpha3
kind: EnvoyFilter
metadata:
  labels:
    istio.io/rev: default
    operator.istio.io/version: 1.4.8
  name: ext-authz-1
  namespace: istio-system
spec:
  configPatches:
  - applyTo: HTTP_FILTER
    match:
      context: SIDECAR_INBOUND
      listener:
        filterChain:
          filter:
            name: envoy.http_connection_manager
            subFilter:
              name: istio_authn
    patch:
      operation: INSERT_AFTER
      value:
        name: envoy.ext_authz
        config:
          grpc_service:
            google_grpc:
              target_uri: 127.0.0.1:9191
              stat_prefix: ext_authz