Ext_authz

[guicassolato]

Make possible for the wasm-shim to issue gRPC Envoy ext_authz requests based on configuration.

Other than the main attributes source, destination, and request of the CheckRequest message, supplying values in the context_extensions field must as well be supported. This will be useful to hint the authorization service lookup without the constraint on the host name as the only unique identifier of effective policies (AuthConfig CRs.)

[david-martin]

@guicassolato Will this change mean that tracing behaves the same as with limitador?
That is, trace ids do not propagate to wasm modules in Istio/Envoy, affecting trace continuity in authorino?
(in which case, we should update the tracing guide at https://docs.kuadrant.io/0.8.0/kuadrant-operator/doc/observability/tracing/ to mention this)

[guicassolato]

@guicassolato Will this change mean that tracing behaves the same as with limitador? That is, trace ids do not propagate to wasm modules in Istio/Envoy, affecting trace continuity in authorino? (in which case, we should update the tracing guide at https://docs.kuadrant.io/0.8.0/kuadrant-operator/doc/observability/tracing/ to mention this)

It probably does, @david-martin. Thanks for pointing this out!