feat: add e2e test to validate webhook conversion between versions

Author: wazery

docs/book/src/multiversion-tutorial/testdata/project/go.mod

@@ -9,6 +9,7 @@ require (
 	k8s.io/api v0.34.0
 	k8s.io/apimachinery v0.34.0
 	k8s.io/client-go v0.34.0
+	k8s.io/utils v0.0.0-20250604170112-4c0f3b243397
 	sigs.k8s.io/controller-runtime v0.22.0
 )
 
@@ -92,7 +93,6 @@ require (
 	k8s.io/component-base v0.34.0 // indirect
 	k8s.io/klog/v2 v2.130.1 // indirect
 	k8s.io/kube-openapi v0.0.0-20250710124328-f3f2b991d03b // indirect
-	k8s.io/utils v0.0.0-20250604170112-4c0f3b243397 // indirect
 	sigs.k8s.io/apiserver-network-proxy/konnectivity-client v0.31.2 // indirect
 	sigs.k8s.io/json v0.0.0-20241014173422-cfa47c3a1cc8 // indirect
 	sigs.k8s.io/randfill v1.0.0 // indirect

docs/book/src/multiversion-tutorial/testdata/project/test/e2e/e2e_test.go

@@ -25,6 +25,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"strings"
 	"time"
 
 	. "github.com/onsi/ginkgo/v2"
@@ -178,9 +179,14 @@ var _ = Describe("Manager", Ordered, func() {
 			cmd := exec.Command("kubectl", "create", "clusterrolebinding", metricsRoleBindingName,
 				"--clusterrole=project-metrics-reader",
 				fmt.Sprintf("--serviceaccount=%s:%s", namespace, serviceAccountName),
-			)
-			_, err := utils.Run(cmd)
-			Expect(err).NotTo(HaveOccurred(), "Failed to create ClusterRoleBinding")
+				"--dry-run=client", "-o", "yaml")
+			output, err := utils.Run(cmd)
+			Expect(err).NotTo(HaveOccurred(), "Failed to generate ClusterRoleBinding YAML")
+
+			cmd = exec.Command("kubectl", "apply", "-f", "-")
+			cmd.Stdin = strings.NewReader(output)
+			_, err = utils.Run(cmd)
+			Expect(err).NotTo(HaveOccurred(), "Failed to apply ClusterRoleBinding")
 
 			By("validating that the metrics service is available")
 			cmd = exec.Command("kubectl", "get", "service", metricsServiceName, "-n", namespace)
@@ -319,7 +325,74 @@ var _ = Describe("Manager", Ordered, func() {
 
 		// +kubebuilder:scaffold:e2e-webhooks-checks
 
-		// TODO: Customize the e2e test suite with scenarios specific to your project.
+		It("should validate webhook conversion between v1 and v2 CronJob versions", func() {
+			By("applying the v1 CronJob sample")
+			cmd := exec.Command("kubectl", "apply", "-f", "config/samples/batch_v1_cronjob.yaml", "-n", namespace)
+			_, err := utils.Run(cmd)
+			Expect(err).NotTo(HaveOccurred(), "Failed to apply v1 CronJob sample")
+
+			By("verifying the v1 CronJob is stored properly")
+			Eventually(func(g Gomega) {
+				cmd := exec.Command("kubectl", "get", "cronjob.batch.tutorial.kubebuilder.io", "cronjob-sample", "-n", namespace, "-o", "json")
+				output, err := utils.Run(cmd)
+				g.Expect(err).NotTo(HaveOccurred())
+
+				var v1CronJob map[string]interface{}
+				err = json.Unmarshal([]byte(output), &v1CronJob)
+				g.Expect(err).NotTo(HaveOccurred())
+
+				// Get spec and verify the schedule field exists
+				v1Spec, ok := v1CronJob["spec"].(map[string]interface{})
+				g.Expect(ok).To(BeTrue(), "Failed to get spec from v1 CronJob")
+				g.Expect(v1Spec["schedule"]).NotTo(BeNil(), "Schedule field should exist in v1 CronJob")
+			}).Should(Succeed())
+
+			By("deleting the v1 CronJob sample")
+			cmd = exec.Command("kubectl", "delete", "-f", "config/samples/batch_v1_cronjob.yaml", "-n", namespace, "--ignore-not-found")
+			_, _ = utils.Run(cmd)
+
+			By("applying the v2 CronJob sample")
+			cmd = exec.Command("kubectl", "apply", "-f", "config/samples/batch_v2_cronjob.yaml", "-n", namespace)
+			_, err = utils.Run(cmd)
+			Expect(err).NotTo(HaveOccurred(), "Failed to apply v2 CronJob sample")
+
+			By("verifying the v2 CronJob is stored properly")
+			Eventually(func(g Gomega) {
+				cmd := exec.Command("kubectl", "get", "cronjob.batch.tutorial.kubebuilder.io", "cronjob-sample", "-n", namespace, "-o", "json")
+				output, err := utils.Run(cmd)
+				g.Expect(err).NotTo(HaveOccurred())
+
+				var v2CronJob map[string]interface{}
+				err = json.Unmarshal([]byte(output), &v2CronJob)
+				g.Expect(err).NotTo(HaveOccurred())
+
+				// Get spec and verify the schedule field exists
+				v2Spec, ok := v2CronJob["spec"].(map[string]interface{})
+				g.Expect(ok).To(BeTrue(), "Failed to get spec from v2 CronJob")
+				g.Expect(v2Spec["schedule"]).NotTo(BeNil(), "Schedule field should exist in v2 CronJob")
+			}).Should(Succeed())
+
+			By("verifying conversion webhook was called by checking controller logs")
+			Eventually(func(g Gomega) {
+				cmd := exec.Command("kubectl", "logs", controllerPodName, "-n", namespace)
+				logs, err := utils.Run(cmd)
+				g.Expect(err).NotTo(HaveOccurred())
+
+				// Verify that conversion webhook was actually called
+				g.Expect(logs).To(ContainSubstring("ConvertTo:"), "Expected to find ConvertTo log indicating conversion webhook was called")
+				g.Expect(logs).To(ContainSubstring("ConvertFrom:"), "Expected to find ConvertFrom log indicating conversion webhook was called")
+
+				// Verify that conversion is happening between the versions
+				g.Expect(logs).To(ContainSubstring("Converting CronJob from Hub version v1 to Spoke version v2"),
+					"Expected v1 to v2 conversion")
+				g.Expect(logs).To(ContainSubstring("Converting CronJob from Spoke version v2 to Hub version v1"),
+					"Expected v2 to v1 conversion")
+			}).Should(Succeed())
+
+			By("cleaning up the v2 CronJob sample")
+			cmd = exec.Command("kubectl", "delete", "-f", "config/samples/batch_v2_cronjob.yaml", "-n", namespace, "--ignore-not-found")
+			_, _ = utils.Run(cmd)
+		})
 		// Consider applying sample/CR(s) and check their status and/or verifying
 		// the reconciliation by using the metrics, i.e.:
 		// metricsOutput := getMetricsOutput()