feat: add support for primary backend cookies in session affinity

Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>

pkg/controller/controller.go

@@ -337,6 +337,9 @@ func (c *Controller) verifyCanary(canary *flaggerv1.Canary) error {
 	if err := verifyKnativeCanary(canary); err != nil {
 		return err
 	}
+	if err := verifySessionAffinity(canary); err != nil {
+		return err
+	}
 
 	return nil
 }
@@ -378,6 +381,16 @@ func verifyKnativeCanary(canary *flaggerv1.Canary) error {
 	return nil
 }
 
+func verifySessionAffinity(canary *flaggerv1.Canary) error {
+	if canary.Spec.Analysis.SessionAffinity != nil {
+		if canary.Spec.Analysis.SessionAffinity.CookieName == canary.Spec.Analysis.SessionAffinity.PrimaryCookieName {
+			return fmt.Errorf("can't use the same cookie name for both primary and cookie name; please update them to be different")
+		}
+	}
+
+	return nil
+}
+
 func checkCustomResourceType(obj interface{}, logger *zap.SugaredLogger) (flaggerv1.Canary, bool) {
 	var roll *flaggerv1.Canary
 	var ok bool

pkg/controller/controller_test.go

@@ -26,6 +26,7 @@ func TestController_verifyCanary(t *testing.T) {
 						Name:      "upstream",
 						Namespace: "test",
 					},
+					Analysis: &flaggerv1.CanaryAnalysis{},
 				},
 			},
 			wantErr: true,
@@ -42,6 +43,7 @@ func TestController_verifyCanary(t *testing.T) {
 						Name:      "upstream",
 						Namespace: "default",
 					},
+					Analysis: &flaggerv1.CanaryAnalysis{},
 				},
 			},
 			wantErr: false,
@@ -103,6 +105,7 @@ func TestController_verifyCanary(t *testing.T) {
 						Kind: "Deployment",
 						Name: "podinfo",
 					},
+					Analysis: &flaggerv1.CanaryAnalysis{},
 				},
 			},
 			wantErr: true,
@@ -121,6 +124,7 @@ func TestController_verifyCanary(t *testing.T) {
 						APIVersion: "serving.knative.dev/v1",
 						Name:       "podinfo",
 					},
+					Analysis: &flaggerv1.CanaryAnalysis{},
 				},
 			},
 			wantErr: true,
@@ -140,6 +144,7 @@ func TestController_verifyCanary(t *testing.T) {
 						APIVersion: "serving.knative.dev/v1",
 						Name:       "podinfo",
 					},
+					Analysis: &flaggerv1.CanaryAnalysis{},
 				},
 			},
 			wantErr: true,
@@ -158,10 +163,29 @@ func TestController_verifyCanary(t *testing.T) {
 						APIVersion: "serving.knative.dev/v1",
 						Name:       "podinfo",
 					},
+					Analysis: &flaggerv1.CanaryAnalysis{},
 				},
 			},
 			wantErr: false,
 		},
+		{
+			name: "session affinity with same cookie names should return an error",
+			canary: flaggerv1.Canary{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "cd-1",
+					Namespace: "default",
+				},
+				Spec: flaggerv1.CanarySpec{
+					Analysis: &flaggerv1.CanaryAnalysis{
+						SessionAffinity: &flaggerv1.SessionAffinity{
+							CookieName:        "smth",
+							PrimaryCookieName: "smth",
+						},
+					},
+				},
+			},
+			wantErr: true,
+		},
 	}
 
 	ctrl := &Controller{