Add runtime cost limit test.

test/integration/apiserver/crd_validation_expressions_test.go

@@ -301,6 +301,36 @@ func TestCustomResourceValidators(t *testing.T) {
 			t.Error("Unexpected error creating custom resource but metadata validation rule")
 		}
 	})
+	t.Run("CR creation MUST fail if a x-kubernetes-validations rule exceeds the runtime cost limit", func(t *testing.T) {
+		structuralWithValidators := crdWithSchema(t, "RuntimeCostLimit", structuralSchemaWithCostLimit)
+		crd, err := fixtures.CreateNewV1CustomResourceDefinition(structuralWithValidators, apiExtensionClient, dynamicClient)
+		if err != nil {
+			t.Errorf("Unexpected error creating custom resource definition: %v", err)
+		}
+		gvr := schema.GroupVersionResource{
+			Group:    crd.Spec.Group,
+			Version:  crd.Spec.Versions[0].Name,
+			Resource: crd.Spec.Names.Plural,
+		}
+		crClient := dynamicClient.Resource(gvr)
+		name1 := names.SimpleNameGenerator.GenerateName("cr-1")
+		cr := &unstructured.Unstructured{Object: map[string]interface{}{
+			"apiVersion": gvr.Group + "/" + gvr.Version,
+			"kind":       crd.Spec.Names.Kind,
+			"metadata": map[string]interface{}{
+				"name": name1,
+			},
+			"spec": map[string]interface{}{
+				"list": genLargeArray(725, 20),
+			},
+		}}
+		_, err = crClient.Create(context.TODO(), cr, metav1.CreateOptions{})
+		if err == nil {
+			t.Fatal("Expected error creating custom resource")
+		} else if !strings.Contains(err.Error(), "call cost exceeds limit") {
+			t.Errorf("Expected error to contain %s but got %v", "call cost exceeds limit", err.Error())
+		}
+	})
 	t.Run("Schema with valid transition rule", func(t *testing.T) {
 		structuralWithValidators := crdWithSchema(t, "ValidTransitionRule", structuralSchemaWithValidTransitionRule)
 		crd, err := fixtures.CreateNewV1CustomResourceDefinition(structuralWithValidators, apiExtensionClient, dynamicClient)
@@ -680,6 +710,14 @@ func nonStructuralCrdWithValidations() *apiextensionsv1beta1.CustomResourceDefin
 	}
 }
 
+func genLargeArray(n, x int64) []int64 {
+	arr := make([]int64, n)
+	for i := int64(0); i < n; i++ {
+		arr[i] = x
+	}
+	return arr
+}
+
 func crdWithSchema(t *testing.T, kind string, schemaJson []byte) *apiextensionsv1.CustomResourceDefinition {
 	plural := strings.ToLower(kind) + "s"
 	var c apiextensionsv1.CustomResourceValidation
@@ -1031,3 +1069,34 @@ var structuralSchemaWithDefaultMapKeyTransitionRule = []byte(`
     }
   }
 }`)
+
+var structuralSchemaWithCostLimit = []byte(`
+{
+  "openAPIV3Schema": {
+    "description": "CRD with CEL validators",
+    "type": "object",
+    "properties": {
+      "spec": {
+        "type": "object",
+        "properties": {
+		  "list": {
+			"type": "array",
+			"maxItems": 725,
+            "items": {
+			  "type": "integer"
+			},
+			"x-kubernetes-validations": [
+		        {
+			      "rule": "self.all(x, self.all(y, x == y))"
+                }
+		      ]
+          }
+	    }
+      },
+      "status": {
+        "type": "object",
+        "properties": {}
+	  }
+    }
+  }
+}`)