Previously SAN validation for prepared queries was broken because we
validated against the name, namespace, and datacenter for prepared
queries.
However, prepared queries can target:
- Services with a name that isn't their own
- Services in multiple datacenters
This means that the SpiffeID to validate needs to be based on the
prepared query endpoints, and not the prepared query's upstream
definition.
This commit updates prepared query clusters to account for that.
The only thing that needed fixing up pertained to this section of the 1.18.x release notes:
> grpc_stats: the default value for stats_for_all_methods is switched from true to false, in order to avoid possible memory exhaustion due to an untrusted downstream sending a large number of unique method names. The previous default value was deprecated in version 1.14.0. This only changes the behavior when the value is not set. The previous behavior can be used by setting the value to true. This behavior change by be overridden by setting runtime feature envoy.deprecated_features.grpc_stats_filter_enable_stats_for_all_methods_by_default.
For now to maintain status-quo I'm explicitly setting `stats_for_all_methods=true` in all versions to avoid relying upon the default.
Additionally the naming of the emitted metrics for these gRPC requests changed slightly so the integration test assertions for `case-grpc` needed adjusting.