Required. The name of the Google Compute Engine in which the cluster resides, which can either be compute zone (for example, us-central1-a) for the zonal clusters or region (for example, us-central1) for regional clusters.
Optional. The relative path on the GKE service the events should be sent to. The value must conform to the definition of a URI path segment (section 3.3 of RFC2396). Examples: "/route", "route", "route/subroute".