From eabef3db30c5b5594c2d8298a69f4b6117bde55d Mon Sep 17 00:00:00 2001
From: stefanprodan <stefan.prodan@gmail.com>
Date: Mon, 25 Feb 2019 03:14:45 +0200
Subject: [PATCH] Router improvements - change virtual service route to canary
 service - keep the existing destination weights on virtual service updates -
 set the match conditions and URI rewrite when changing the traffic weight

---
 pkg/controller/router.go      | 20 ++++++++++++--------
 pkg/controller/router_test.go |  4 ++--
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/pkg/controller/router.go b/pkg/controller/router.go
index dd99873a1..869f2c071 100644
--- a/pkg/controller/router.go
+++ b/pkg/controller/router.go
@@ -180,7 +180,7 @@ func (c *CanaryRouter) syncVirtualService(cd *flaggerv1.Canary) error {
 		},
 		{
 			Destination: istiov1alpha3.Destination{
-				Host: targetName,
+				Host: fmt.Sprintf("%s-canary", targetName),
 				Port: istiov1alpha3.PortSelector{
 					Number: uint32(cd.Spec.Service.Port),
 				},
@@ -230,13 +230,15 @@ func (c *CanaryRouter) syncVirtualService(cd *flaggerv1.Canary) error {
 		return fmt.Errorf("VirtualService %s.%s query error %v", targetName, cd.Namespace, err)
 	}
 
-	// update service
+	// update service but keep the original destination weights
 	if virtualService != nil {
 		if diff := cmp.Diff(newSpec, virtualService.Spec, cmpopts.IgnoreTypes(istiov1alpha3.DestinationWeight{})); diff != "" {
+			//fmt.Println(diff)
 			vtClone := virtualService.DeepCopy()
 			vtClone.Spec = newSpec
-			//TODO: keep original destination weights
-			//vtClone.Spec.Http = virtualService.Spec.Http
+			if len(virtualService.Spec.Http) > 0 {
+				vtClone.Spec.Http[0].Route = virtualService.Spec.Http[0].Route
+			}
 			_, err = c.istioClient.NetworkingV1alpha3().VirtualServices(cd.Namespace).Update(vtClone)
 			if err != nil {
 				return fmt.Errorf("VirtualService %s.%s update error %v", targetName, cd.Namespace, err)
@@ -272,15 +274,15 @@ func (c *CanaryRouter) GetRoutes(cd *flaggerv1.Canary) (
 			if route.Destination.Host == fmt.Sprintf("%s-primary", targetName) {
 				primary = route
 			}
-			if route.Destination.Host == targetName {
+			if route.Destination.Host == fmt.Sprintf("%s-canary", targetName) {
 				canary = route
 			}
 		}
 	}
 
 	if primary.Weight == 0 && canary.Weight == 0 {
-		err = fmt.Errorf("VirtualService %s.%s does not contain routes for %s and %s",
-			targetName, cd.Namespace, fmt.Sprintf("%s-primary", targetName), targetName)
+		err = fmt.Errorf("VirtualService %s.%s does not contain routes for %s-primary and %s-canary",
+			targetName, cd.Namespace, targetName, targetName)
 	}
 
 	return
@@ -305,7 +307,9 @@ func (c *CanaryRouter) SetRoutes(
 	vsCopy := vs.DeepCopy()
 	vsCopy.Spec.Http = []istiov1alpha3.HTTPRoute{
 		{
-			Route: []istiov1alpha3.DestinationWeight{primary, canary},
+			Match:   cd.Spec.Service.Match,
+			Rewrite: cd.Spec.Service.Rewrite,
+			Route:   []istiov1alpha3.DestinationWeight{primary, canary},
 		},
 	}
 
diff --git a/pkg/controller/router_test.go b/pkg/controller/router_test.go
index 415279244..64059b945 100644
--- a/pkg/controller/router_test.go
+++ b/pkg/controller/router_test.go
@@ -15,7 +15,7 @@ func TestCanaryRouter_SyncClusterIPServices(t *testing.T) {
 		t.Fatal(err.Error())
 	}
 
-	canarySvc, err := mocks.kubeClient.CoreV1().Services("default").Get("podinfo", metav1.GetOptions{})
+	canarySvc, err := mocks.kubeClient.CoreV1().Services("default").Get("podinfo-canary", metav1.GetOptions{})
 	if err != nil {
 		t.Fatal(err.Error())
 	}
@@ -177,7 +177,7 @@ func TestCanaryRouter_SetRoutes(t *testing.T) {
 			if route.Destination.Host == fmt.Sprintf("%s-primary", mocks.canary.Spec.TargetRef.Name) {
 				pRoute = route
 			}
-			if route.Destination.Host == mocks.canary.Spec.TargetRef.Name {
+			if route.Destination.Host == fmt.Sprintf("%s-canary", mocks.canary.Spec.TargetRef.Name) {
 				cRoute = route
 			}
 		}