)

type Instance struct {
	structure     any
	isJSON        bool
	constraints   []constraint
	creationError error
}

type constraint func() error

// ForProto creates a structpath Instance by marshaling the proto to JSON and then evaluating over that
// structure. This is the most generally useful form as serialization to JSON also automatically

		s := xds.NewFakeDiscoveryServer(t, xds.FakeOptions{})
		proxy := s.SetupProxy(&model.Proxy{
			IPAddresses: []string{"10.2.0.1"},
			ID:          "app3.testns",
		})
		structpath.ForProto(xdstest.ToDiscoveryResponse(s.Listeners(proxy))).
			Exists("{.resources[?(@.address.socketAddress.portValue==15001)]}").
			Select("{.resources[?(@.address.socketAddress.portValue==15001)]}").

// This essentially just waits for the Sidecar to be applied, without sleeping.
func WaitUntilNotCallable(c echo.Instance, dest echo.Instance) error {
	accept := func(cfg *admin.ConfigDump) (bool, error) {
		validator := structpath.ForProto(cfg)
		for _, port := range dest.Config().Ports {
			clusterName := clusterName(dest, port)
			// Ensure that we have an outbound configuration for the target port.