Merge pull request kubernetes#127303 from omerap12/issue_127287

Improve message prefer a domain-qualified finalizer

Author: k8s-ci-robot

staging/src/k8s.io/apiextensions-apiserver/pkg/registry/customresource/validator.go

@@ -86,7 +86,11 @@ func validateKubeFinalizerName(stringValue string, fldPath *field.Path) []string
 	}
 	if len(strings.Split(stringValue, "/")) == 1 {
 		if !standardFinalizers.Has(stringValue) {
-			allWarnings = append(allWarnings, fmt.Sprintf("%s: %q: prefer a domain-qualified finalizer name to avoid accidental conflicts with other finalizer writers", fldPath.String(), stringValue))
+			if strings.Contains(stringValue, ".") {
+				allWarnings = append(allWarnings, fmt.Sprintf("%s: %q: prefer a domain-qualified finalizer name including a path (/) to avoid accidental conflicts with other finalizer writers", fldPath.String(), stringValue))
+			} else {
+				allWarnings = append(allWarnings, fmt.Sprintf("%s: %q: prefer a domain-qualified finalizer name to avoid accidental conflicts with other finalizer writers", fldPath.String(), stringValue))
+			}
 		}
 	}
 	return allWarnings

test/integration/apiserver/field_validation_test.go

@@ -2937,6 +2937,13 @@ func testFinalizerValidationApplyCreateAndUpdateCRD(t *testing.T, rest rest.Inte
 			name:      "create-crd-with-valid-finalizer",
 			finalizer: []string{"kubernetes.io/valid-finalizer"},
 		},
+		{
+			name:      "create-crd-with-fqdn-like-finalizer-without-path",
+			finalizer: []string{"finalizer.without.valid-path.io"},
+			expectCreateWarnings: []string{
+				`metadata.finalizers: "finalizer.without.valid-path.io": prefer a domain-qualified finalizer name including a path (/) to avoid accidental conflicts with other finalizer writers`,
+			},
+		},
 		{
 			name:             "update-crd-with-invalid-finalizer",
 			finalizer:        []string{"invalid-finalizer"},