defaultRouteAction property

defaultRouteAction takes effect when none of the hostRules match.

The load balancer performs advanced routing actions, such as URL rewrites and header transformations, before forwarding the request to the selected backend. If defaultRouteAction specifies any weightedBackendServices, defaultService must not be set. Conversely if defaultService is set, defaultRouteAction cannot contain any weightedBackendServices. Only one of defaultRouteAction or defaultUrlRedirect must be set. URL maps for classic Application Load Balancers only support the urlRewrite action within defaultRouteAction. defaultRouteAction has no effect when the URL map is bound to a target gRPC proxy that has the validateForProxyless field set to true.