DeclarativeValidation [page]deterministic

Enables declarative validation of in-tree Kubernetes APIs. When enabled, APIs with declarative validation rules (defined using IDL tags in the Go code) will have both the generated declarative validation code and the original hand-written validation code executed. The results are compared, and any discrepancies are reported via the `declarative_validation_mismatch_total` metric. Only the hand-written validation result is returned to the user (eg: actually validates in the request path). The original hand-written validation are still the authoritative validations when this is enabled but this can be changed if the [DeclarativeValidationBeta feature gate](/docs/reference/command-line-tools-reference/feature-gates/DeclarativeValidationBeta/) is enabled in addition to this gate. This feature gate only operates on the `kube-apiserver` component.