Enable Access Log Service for log streaming

[mgolding5010]

kgateway version

1.18

Is your feature request related to a problem? Please describe.

Currently, filter_state data is lost between gateway-proxy and ALS.

Describe the solution you'd like

Enable Access Log Service to have logs streamed to (gRPC) with the purpose of:

1. establishing a logging contract
2. stream the logs to long-term storage, in a consistent format, for visualisation purposes

To work with WASM plugins that enrich logs through filter_state or dynamic_metadata.

Describe alternatives you've considered

No response

Additional Context

kgateway doesn’t provide a way of enabling the filter_states_objects_to_log. If provided, it should be possible to ensure proxy's dataplane includes the required filter_state objects.

[soloio-bot]

Zendesk ticket #5351 has been linked to this issue.

[soloio-bot]

Zendesk ticket #5351 has been linked to this issue.

[soloio-bot]

Zendesk ticket #5351 has been linked to this issue.

[DuncanDoyle]

Feature in Envoy: https://docs.solo.io/gloo-edge/main/reference/api/github.com/solo-io/gloo/projects/gloo/api/v1/options/als/als.proto.sk/#grpcservice (see: filter_state_objects_to_log).

Our current proto which does seem to expose this field: https://docs.solo.io/gloo-edge/main/reference/api/github.com/solo-io/gloo/projects/gloo/api/v1/options/als/als.proto.sk/#grpcservice

[nfuden]

This is where we perform the translation between the two https://github.com/kgateway-dev/kgateway/blame/6a1a4b56883da2d025912b618430e4dd41ccd50d/internal/kgateway/extensions2/plugins/httplistenerpolicy/access_logging_converter.go#L387

If someone wants to contribute this then its a matter of plumbing from what duncan noted through here and then hopefully writing a test.
The test may be a little more gnarly as the implementor would have to decdie on a filter to do that.
Ideally we would consider either a use case like the one mentioned here with WASM OR use a dedicated filter such as the set_filter_state filter however the latter is not currently to my knowledge exposed as configurable via kgateway constructs.

[nfuden]

Note for those following along from Solo. Copied this to https://github.com/solo-io/solo-projects/issues/7923 for near term Gateway work.

Keeping this issue as we should support streaming access logs in kgateway as well!