test(e2e): wait for webhook to work after disruption (cloudnative-pg#7184)

Disruption tests could end with the webhook not yet able to reply. Wait
until we know it can validate requests.

Closes cloudnative-pg#7182

Signed-off-by: Francesco Canovai <francesco.canovai@enterprisedb.com>
(cherry picked from commit 2dc763a)

Author: fcanovai

tests/e2e/operator_unavailable_test.go

@@ -18,11 +18,15 @@ package e2e
 
 import (
 	"sync"
+	"time"
 
 	corev1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	ctrlclient "sigs.k8s.io/controller-runtime/pkg/client"
 
+	apiv1 "github.com/cloudnative-pg/cloudnative-pg/api/v1"
 	"github.com/cloudnative-pg/cloudnative-pg/pkg/specs"
 	"github.com/cloudnative-pg/cloudnative-pg/pkg/utils"
 	"github.com/cloudnative-pg/cloudnative-pg/tests"
@@ -224,6 +228,20 @@ var _ = Describe("Operator unavailable", Serial, Label(tests.LabelDisruptive, te
 				}, timeout).Should(BeTrue())
 			})
 			AssertDataExpectedCount(env, tableLocator, 2)
+
+			// There is a chance that the webhook is not able to reach the new operator pod yet.
+			// This could make following tests fail, so we need to wait for the webhook to be working again.
+			By("verifying the webhook is working again", func() {
+				invalidCluster := &apiv1.Cluster{
+					ObjectMeta: metav1.ObjectMeta{Namespace: namespace, Name: "invalid"},
+					Spec:       apiv1.ClusterSpec{Instances: 1},
+				}
+				Eventually(func(g Gomega) {
+					err := env.Client.Create(env.Ctx, invalidCluster)
+					g.Expect(errors.IsInvalid(err)).To(BeTrue())
+					g.Expect(err).To(MatchError(ContainSubstring("spec.storage.size")))
+				}).WithTimeout(10 * time.Second).Should(Succeed())
+			})
 		})
 	})
 })