From 2dea130bde18b9e5ad9aea11c42a0d947d854548 Mon Sep 17 00:00:00 2001
From: Ruixian Song <songrx@google.com>
Date: Tue, 2 May 2023 13:55:06 -0700
Subject: [PATCH] Add CheckBackendConfigAnnotation rule to check-gke-ingress

---
 cmd/check-gke-ingress/app/ingress/rule.go     | 27 ++++++++
 .../app/ingress/rule_test.go                  | 68 +++++++++++++++++++
 2 files changed, 95 insertions(+)

diff --git a/cmd/check-gke-ingress/app/ingress/rule.go b/cmd/check-gke-ingress/app/ingress/rule.go
index d52af04d8a..9071ca1e25 100644
--- a/cmd/check-gke-ingress/app/ingress/rule.go
+++ b/cmd/check-gke-ingress/app/ingress/rule.go
@@ -18,6 +18,7 @@ package ingress
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 
 	corev1 "k8s.io/api/core/v1"
@@ -25,6 +26,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/ingress-gce/cmd/check-gke-ingress/app/report"
+	"k8s.io/ingress-gce/pkg/annotations"
 )
 
 func CheckServiceExistence(namespace, name string, client clientset.Interface) (*corev1.Service, string, string) {
@@ -37,3 +39,28 @@ func CheckServiceExistence(namespace, name string, client clientset.Interface) (
 	}
 	return svc, report.Passed, fmt.Sprintf("Service %s/%s found", namespace, name)
 }
+
+func CheckBackendConfigAnnotation(svc *corev1.Service) (*annotations.BackendConfigs, string, string) {
+	val, ok := getBackendConfigAnnotation(svc)
+	if !ok {
+		return nil, report.Skipped, fmt.Sprintf("Service %s/%s does not have backendconfig annotation", svc.Namespace, svc.Name)
+	}
+	beConfigs := &annotations.BackendConfigs{}
+	if err := json.Unmarshal([]byte(val), beConfigs); err != nil {
+		return nil, report.Failed, fmt.Sprintf("BackendConfig annotation is invalid in service %s/%s", svc.Namespace, svc.Name)
+	}
+	if beConfigs.Default == "" && beConfigs.Ports == nil {
+		return nil, report.Failed, fmt.Sprintf("BackendConfig annotation is missing both `default` and `ports` field in service %s/%s", svc.Namespace, svc.Name)
+	}
+	return beConfigs, report.Passed, fmt.Sprintf("BackendConfig annotation is valid in service %s/%s", svc.Namespace, svc.Name)
+}
+
+func getBackendConfigAnnotation(svc *corev1.Service) (string, bool) {
+	for _, bcKey := range []string{annotations.BackendConfigKey, annotations.BetaBackendConfigKey} {
+		val, ok := svc.Annotations[bcKey]
+		if ok {
+			return val, ok
+		}
+	}
+	return "", false
+}
diff --git a/cmd/check-gke-ingress/app/ingress/rule_test.go b/cmd/check-gke-ingress/app/ingress/rule_test.go
index e74f69b9ed..5e0bbbea12 100644
--- a/cmd/check-gke-ingress/app/ingress/rule_test.go
+++ b/cmd/check-gke-ingress/app/ingress/rule_test.go
@@ -24,6 +24,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes/fake"
 	"k8s.io/ingress-gce/cmd/check-gke-ingress/app/report"
+	"k8s.io/ingress-gce/pkg/annotations"
 )
 
 func TestCheckServiceExistence(t *testing.T) {
@@ -71,3 +72,70 @@ func TestCheckServiceExistence(t *testing.T) {
 		}
 	}
 }
+
+func TestCheckBackendConfigAnnotation(t *testing.T) {
+	for _, tc := range []struct {
+		desc   string
+		svc    corev1.Service
+		expect string
+	}{
+		{
+			desc:   "empty input",
+			expect: report.Skipped,
+		},
+		{
+			desc: "service without beconfig annotation",
+			svc: corev1.Service{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "svc-1",
+					Namespace: "test",
+				},
+			},
+			expect: report.Skipped,
+		},
+		{
+			desc: "service with beconfig annotation",
+			svc: corev1.Service{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "svc-1",
+					Namespace: "test",
+					Annotations: map[string]string{
+						annotations.BackendConfigKey: `{"ports": {"port1": "beconfig"}}`,
+					},
+				},
+			},
+			expect: report.Passed,
+		},
+		{
+			desc: "service with malformed default field in beconfig annotation",
+			svc: corev1.Service{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "svc-1",
+					Namespace: "test",
+					Annotations: map[string]string{
+						annotations.BackendConfigKey: `{"default": {"port1": "beconfig"}}`,
+					},
+				},
+			},
+			expect: report.Failed,
+		},
+		{
+			desc: "service with malformed ports field in beconfig annotation",
+			svc: corev1.Service{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "svc-1",
+					Namespace: "test",
+					Annotations: map[string]string{
+						annotations.BackendConfigKey: `{"port1": "beconfig1", "port2": "beconfig2"}`,
+					},
+				},
+			},
+			expect: report.Failed,
+		},
+	} {
+		_, res, _ := CheckBackendConfigAnnotation(&tc.svc)
+		if res != tc.expect {
+			t.Errorf("For test case %q, expect check result = %s, but got %s", tc.desc, tc.expect, res)
+		}
+	}
+}