fix: gateway router should wait for accepted condition

go.mod

@@ -29,6 +29,7 @@ require (
 	k8s.io/client-go v0.34.1
 	k8s.io/code-generator v0.34.1
 	k8s.io/klog/v2 v2.130.1
+	k8s.io/utils v0.0.0-20250604170112-4c0f3b243397
 	knative.dev/serving v0.46.6
 )
 
@@ -99,7 +100,6 @@ require (
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	k8s.io/gengo/v2 v2.0.0-20250604051438-85fd79dbfd9f // indirect
 	k8s.io/kube-openapi v0.0.0-20250710124328-f3f2b991d03b // indirect
-	k8s.io/utils v0.0.0-20250604170112-4c0f3b243397 // indirect
 	knative.dev/networking v0.0.0-20250902160145-7dad473f6351 // indirect
 	knative.dev/pkg v0.0.0-20250909011231-077dcf0d00e8 // indirect
 	sigs.k8s.io/json v0.0.0-20241014173422-cfa47c3a1cc8 // indirect

pkg/router/gateway_api.go

@@ -273,6 +273,26 @@ func (gwr *GatewayAPIRouter) GetRoutes(canary *flaggerv1.Canary) (
 		err = fmt.Errorf("HTTPRoute %s.%s get error: %w", apexSvcName, hrNamespace, err)
 		return
 	}
+
+	currentGeneration := httpRoute.GetGeneration()
+	for _, parentRef := range httpRoute.Spec.CommonRouteSpec.ParentRefs {
+		for _, parentStatus := range httpRoute.Status.Parents {
+			if !reflect.DeepEqual(parentStatus.ParentRef, parentRef) {
+				continue
+			}
+
+			for _, condition := range parentStatus.Conditions {
+				if condition.Type == string(v1.RouteConditionAccepted) && (condition.Status != metav1.ConditionTrue || condition.ObservedGeneration < currentGeneration) {
+					err = fmt.Errorf(
+						"HTTPRoute %s.%s parent %s is not ready (status: %s, observed generation: %d, current generation: %d)",
+						apexSvcName, hrNamespace, parentRef.Name, string(condition.Status), condition.ObservedGeneration, currentGeneration,
+					)
+					return 0, 0, false, err
+				}
+			}
+		}
+	}
+
 	var weightedRule *v1.HTTPRouteRule
 	for _, rule := range httpRoute.Spec.Rules {
 		// If session affinity is enabled, then we are only interested in the rule

pkg/router/gateway_api_test.go

@@ -28,6 +28,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/utils/ptr"
 
 	flaggerv1 "github.com/fluxcd/flagger/pkg/apis/flagger/v1beta1"
 	v1 "github.com/fluxcd/flagger/pkg/apis/gatewayapi/v1"
@@ -603,3 +604,106 @@ func TestGatewayAPIRouter_makeFilters_CORS(t *testing.T) {
 	// Assert MaxAge (24h = 86400 seconds)
 	assert.Equal(t, int32(86400), corsFilter.CORS.MaxAge)
 }
+
+func TestGatewayAPIRouter_GetRoutes(t *testing.T) {
+	canary := newTestGatewayAPICanary()
+	mocks := newFixture(canary)
+	router := &GatewayAPIRouter{
+		gatewayAPIClient: mocks.meshClient,
+		kubeClient:       mocks.kubeClient,
+		logger:           mocks.logger,
+	}
+
+	httpRoute := &v1.HTTPRoute{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:       "podinfo",
+			Generation: 1,
+		},
+		Spec: v1.HTTPRouteSpec{
+			Rules: []v1.HTTPRouteRule{
+				{
+					BackendRefs: []v1.HTTPBackendRef{
+						{
+							BackendRef: v1.BackendRef{
+								BackendObjectReference: v1.BackendObjectReference{
+									Name: "podinfo-canary",
+								},
+								Weight: ptr.To(int32(10)),
+							},
+						},
+						{
+							BackendRef: v1.BackendRef{
+								BackendObjectReference: v1.BackendObjectReference{
+									Name: "podinfo-primary",
+								},
+								Weight: ptr.To(int32(90)),
+							},
+						},
+					},
+				},
+			},
+			CommonRouteSpec: v1.CommonRouteSpec{
+				ParentRefs: []v1.ParentReference{
+					{
+						Name: "podinfo",
+					},
+				},
+			},
+		},
+	}
+	httpRoute, err := router.gatewayAPIClient.GatewayapiV1().HTTPRoutes("default").Create(context.TODO(), httpRoute, metav1.CreateOptions{})
+	require.NoError(t, err)
+
+	t.Run("httproute generation", func(t *testing.T) {
+		httpRoute.ObjectMeta.Generation = 5
+		httpRoute.Status.Parents = []v1.RouteParentStatus{
+			{
+				ParentRef: v1.ParentReference{
+					Name:        "podinfo",
+					SectionName: ptr.To(v1.SectionName("https")),
+				},
+				Conditions: []metav1.Condition{
+					{
+						Type:               string(v1.RouteConditionAccepted),
+						Status:             metav1.ConditionTrue,
+						ObservedGeneration: 1,
+					},
+				},
+			},
+			{
+				ParentRef: v1.ParentReference{
+					Name: "podinfo",
+				},
+				Conditions: []metav1.Condition{
+					{
+						Type:               string(v1.RouteConditionAccepted),
+						Status:             metav1.ConditionFalse,
+						ObservedGeneration: 4,
+					},
+				},
+			},
+		}
+		httpRoute, err := router.gatewayAPIClient.GatewayapiV1().HTTPRoutes("default").Update(context.TODO(), httpRoute, metav1.UpdateOptions{})
+		require.NoError(t, err)
+
+		_, _, _, err = router.GetRoutes(canary)
+		require.Error(t, err)
+
+		httpRoute.Status.Parents[1].Conditions[0].ObservedGeneration = 5
+		_, err = router.gatewayAPIClient.GatewayapiV1().HTTPRoutes("default").Update(context.TODO(), httpRoute, metav1.UpdateOptions{})
+		require.NoError(t, err)
+
+		_, _, _, err = router.GetRoutes(canary)
+		require.Error(t, err)
+
+		httpRoute.Status.Parents[1].Conditions[0].Status = metav1.ConditionTrue
+		_, err = router.gatewayAPIClient.GatewayapiV1().HTTPRoutes("default").Update(context.TODO(), httpRoute, metav1.UpdateOptions{})
+		require.NoError(t, err)
+
+		primaryWeight, canaryWeight, mirrored, err := router.GetRoutes(canary)
+		require.NoError(t, err)
+		assert.Equal(t, 90, primaryWeight)
+		assert.Equal(t, 10, canaryWeight)
+		assert.False(t, mirrored)
+	})
+}