Extension configurationΒΆ
Each configuration resource in Envoy has a type URL in the typed_config. This type corresponds to a versioned schema. If the type URL uniquely identifies an extension capable of interpreting the configuration, then the extension is selected regardless of the name field. In this case the name field becomes optional and can be used as an identifier or as an annotation for the particular instance of the extension configuration. For example, the following filter configuration snippet is permitted:
name: front-http-proxy
typed_config:
"@type": type.googleapis.com/envoy.config.filter.network.http_connection_manager.v2.HttpConnectionManager
stat_prefix: ingress_http
codec_type: AUTO
rds:
route_config_name: local_route
config_source:
api_config_source:
api_type: GRPC
grpc_services:
envoy_grpc:
cluster_name: xds_cluster
http_filters:
- name: front-router
typed_config:
"@type": type.googleapis.com/envoy.config.filter.http.router.v2.Router
dynamic_stats: true
In case the control plane lacks the schema definitions for an extension, udpa.type.v1.TypedStruct should be used as a generic container. The type URL inside it is then used by a client to convert the contents to a typed configuration resource. For example, the above example could be written as follows:
name: front-http-proxy
typed_config:
"@type": type.googleapis.com/udpa.type.v1.TypedStruct
type_url: type.googleapis.com/envoy.config.filter.network.http_connection_manager.v2.HttpConnectionManager
value:
stat_prefix: ingress_http
codec_type: AUTO
rds:
route_config_name: local_route
config_source:
api_config_source:
api_type: GRPC
grpc_services:
envoy_grpc:
cluster_name: xds_cluster
http_filters:
- name: front-router
typed_config:
"@type": type.googleapis.com/udpa.type.v1.TypedStruct
type_url: type.googleapis.com/envoy.config.filter.http.router.v2.Router