Support for BlueGreen rollout preview endpoint

Makefile

@@ -131,6 +131,7 @@ gen-yaml:
 	kustomize build ./install/sample/overlays/rollout-bluegreen > ./out/yaml/sample-greeting-rollout-bluegreen.yaml
 	kustomize build ./install/sample/overlays/remote > ./out/yaml/remotecluster_sample.yaml
 	cp ./install/sample/sample_dep.yaml ./out/yaml/sample_dep.yaml
+	cp ./install/sample/greeting_preview.yaml ./out/yaml/greeting_preview.yaml
 	cp ./install/sample/gtp.yaml ./out/yaml/gtp.yaml
 	cp ./install/sample/gtp_failover.yaml ./out/yaml/gtp_failover.yaml
 	cp ./install/sample/gtp_topology.yaml ./out/yaml/gtp_topology.yaml

admiral/cmd/admiral/cmd/root.go

@@ -4,15 +4,16 @@ import (
 	"context"
 	"flag"
 	"fmt"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+
 	"github.com/istio-ecosystem/admiral/admiral/pkg/apis/admiral/routes"
 	"github.com/istio-ecosystem/admiral/admiral/pkg/apis/admiral/server"
 	"github.com/istio-ecosystem/admiral/admiral/pkg/clusters"
 	"github.com/istio-ecosystem/admiral/admiral/pkg/controller/common"
 	log "github.com/sirupsen/logrus"
-	"os"
-	"os/signal"
-	"syscall"
-	"time"
 
 	"github.com/spf13/cobra"
 )
@@ -103,6 +104,8 @@ func GetRootCmd(args []string) *cobra.Command {
 		"The label value, on a namespace, which tells Istio to perform sidecar injection")
 	rootCmd.PersistentFlags().StringVar(&params.HostnameSuffix, "hostname_suffix", "global",
 		"The hostname suffix to customize the cname generated by admiral. Default suffix value will be \"global\"")
+	rootCmd.PersistentFlags().StringVar(&params.PreviewHostnamePrefix, "preview_hostname_prefix", "preview",
+		"The hostname prefix to customize the cname generated by admiral for bluegreen rollout preview service. Default suffix value will be \"preview\"")
 	rootCmd.PersistentFlags().StringVar(&params.LabelSet.WorkloadIdentityKey, "workload_identity_key", "identity",
 		"The workload identity  key, on deployment which holds identity value used to generate cname by admiral. Default label key will be \"identity\" Admiral will look for a label with this key. If present, that will be used. If not, it will try an annotation (for use cases where an identity is longer than 63 chars)")
 	rootCmd.PersistentFlags().StringVar(&params.LabelSet.GlobalTrafficDeploymentLabel, "globaltraffic_deployment_label", "identity",

admiral/pkg/clusters/handler.go

@@ -747,7 +747,7 @@ func copyEndpoint(e *v1alpha32.ServiceEntry_Endpoint) *v1alpha32.ServiceEntry_En
 
 // A rollout can use one of 2 stratergies :-
 // 1. Canary strategy - which can use a virtual service to manage the weights associated with a stable and canary service. Admiral created endpoints in service entries will use the weights assigned in the Virtual Service
-// 2. Blue green strategy- this contains 2 service instances in a namespace, an active service and a preview service. Admiral will always use the active service
+// 2. Blue green strategy- this contains 2 service instances in a namespace, an active service and a preview service. Admiral will use repective service to create active and preview endpoints
 func getServiceForRollout(rc *RemoteController, rollout *argo.Rollout) map[string]*WeightedService {
 
 	if rollout == nil {
@@ -769,9 +769,12 @@ func getServiceForRollout(rc *RemoteController, rollout *argo.Rollout) map[strin
 	var istioCanaryWeights = make(map[string]int32)
 
 	var blueGreenActiveService string
+	var blueGreenPreviewService string
+
 	if rolloutStrategy.BlueGreen != nil {
-		// If rollout uses blue green strategy, use the active service
+		// If rollout uses blue green strategy
 		blueGreenActiveService = rolloutStrategy.BlueGreen.ActiveService
+		blueGreenPreviewService = rolloutStrategy.BlueGreen.PreviewService
 	} else if rolloutStrategy.Canary != nil && rolloutStrategy.Canary.TrafficRouting != nil && rolloutStrategy.Canary.TrafficRouting.Istio != nil {
 		canaryService = rolloutStrategy.Canary.CanaryService
 		stableService = rolloutStrategy.Canary.StableService
@@ -844,7 +847,7 @@ func getServiceForRollout(rc *RemoteController, rollout *argo.Rollout) map[strin
 		var service = servicesInNamespace[s]
 		var match = true
 		//skip services that are not referenced in the rollout
-		if len(blueGreenActiveService) > 0 && service.ObjectMeta.Name != blueGreenActiveService {
+		if len(blueGreenActiveService) > 0 && len(blueGreenPreviewService) > 0 && service.ObjectMeta.Name != blueGreenActiveService && service.ObjectMeta.Name != blueGreenPreviewService {
 			log.Infof("Skipping service=%s for rollout=%s in namespace=%s and cluster=%s", service.Name, rollout.Name, rollout.Namespace, rc.ClusterID)
 			continue
 		}
@@ -865,8 +868,11 @@ func getServiceForRollout(rc *RemoteController, rollout *argo.Rollout) map[strin
 		if match {
 			ports := GetMeshPortsForRollout(rc.ClusterID, service, rollout)
 			if len(ports) > 0 {
-				//if the strategy is bluegreen or using canary with NO istio traffic management, pick the first service that matches
-				if len(istioCanaryWeights) == 0 {
+				// if the strategy is bluegreen return matched services
+				// else if using canary with NO istio traffic management, pick the first service that matches
+				if rolloutStrategy.BlueGreen != nil {
+					matchedServices[service.Name] = &WeightedService{Weight: 1, Service: service}
+				} else if len(istioCanaryWeights) == 0 {
 					matchedServices[service.Name] = &WeightedService{Weight: 1, Service: service}
 					break
 				}

admiral/pkg/clusters/registry_test.go

@@ -2,9 +2,13 @@ package clusters
 
 import (
 	"context"
+	"strings"
+	"testing"
+	"time"
+
 	"github.com/google/go-cmp/cmp"
 	depModel "github.com/istio-ecosystem/admiral/admiral/pkg/apis/admiral/model"
-	"github.com/istio-ecosystem/admiral/admiral/pkg/apis/admiral/v1"
+	v1 "github.com/istio-ecosystem/admiral/admiral/pkg/apis/admiral/v1"
 	"github.com/istio-ecosystem/admiral/admiral/pkg/controller/admiral"
 	"github.com/istio-ecosystem/admiral/admiral/pkg/controller/common"
 	"github.com/istio-ecosystem/admiral/admiral/pkg/test"
@@ -17,9 +21,6 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/clientcmd"
-	"strings"
-	"testing"
-	"time"
 )
 
 func init() {
@@ -36,6 +37,7 @@ func init() {
 		SecretResolver:             "",
 		WorkloadSidecarUpdate:      "enabled",
 		WorkloadSidecarName:        "default",
+		PreviewHostnamePrefix:      "preview",
 	}
 
 	p.LabelSet.WorkloadIdentityKey = "identity"
@@ -449,24 +451,24 @@ func TestUpdateCacheController(t *testing.T) {
 
 	//Struct of test case info. Name is required.
 	testCases := []struct {
-		name string
-		oldConfig *rest.Config
-		newConfig *rest.Config
-		clusterId string
+		name          string
+		oldConfig     *rest.Config
+		newConfig     *rest.Config
+		clusterId     string
 		shouldRefresh bool
 	}{
 		{
-			name: "Should update controller when kubeconfig changes",
-			oldConfig: originalConfig,
-			newConfig: changedConfig,
-			clusterId: "test.cluster",
+			name:          "Should update controller when kubeconfig changes",
+			oldConfig:     originalConfig,
+			newConfig:     changedConfig,
+			clusterId:     "test.cluster",
 			shouldRefresh: true,
 		},
 		{
-			name: "Should not update controller when kubeconfig doesn't change",
-			oldConfig: originalConfig,
-			newConfig: originalConfig,
-			clusterId: "test.cluster",
+			name:          "Should not update controller when kubeconfig doesn't change",
+			oldConfig:     originalConfig,
+			newConfig:     originalConfig,
+			clusterId:     "test.cluster",
 			shouldRefresh: false,
 		},
 	}
@@ -476,7 +478,7 @@ func TestUpdateCacheController(t *testing.T) {
 		t.Run(c.name, func(t *testing.T) {
 			hook := logTest.NewGlobal()
 			rr.RemoteControllers[c.clusterId].ApiServer = c.oldConfig.Host
-			d, err := admiral.NewDeploymentController(make(chan struct{}), &test.MockDeploymentHandler{}, c.oldConfig,  time.Second*time.Duration(300))
+			d, err := admiral.NewDeploymentController(make(chan struct{}), &test.MockDeploymentHandler{}, c.oldConfig, time.Second*time.Duration(300))
 			if err != nil {
 				t.Fatalf("Unexpected error creating controller %v", err)
 			}

admiral/pkg/clusters/serviceentry.go

@@ -62,6 +62,7 @@ func modifyServiceEntryForNewServiceOrPod(event admiral.EventType, env string, s
 	var serviceEntries = make(map[string]*networking.ServiceEntry)
 
 	var cname string
+	cnames := make(map[string]string)
 	var serviceInstance *k8sV1.Service
 	var weightedServices map[string]*WeightedService
 	var rollout *admiral.RolloutClusterEntry
@@ -104,6 +105,7 @@ func modifyServiceEntryForNewServiceOrPod(event admiral.EventType, env string, s
 			localMeshPorts := GetMeshPortsForRollout(rc.ClusterID, serviceInstance, rolloutInstance)
 
 			cname = common.GetCnameForRollout(rolloutInstance, common.GetWorkloadIdentifier(), common.GetHostnameSuffix())
+			cnames[cname] = "1"
 			sourceRollouts[rc.ClusterID] = rolloutInstance
 			createServiceEntryForRollout(event, rc, remoteRegistry.AdmiralCache, localMeshPorts, rolloutInstance, serviceEntries)
 		} else {
@@ -132,12 +134,17 @@ func modifyServiceEntryForNewServiceOrPod(event admiral.EventType, env string, s
 		localFqdn := serviceInstance.Name + common.Sep + serviceInstance.Namespace + common.DotLocalDomainSuffix
 		rc := remoteRegistry.RemoteControllers[sourceCluster]
 		var meshPorts map[string]uint32
+		isBlueGreenStrategy := false
+
+		if len(sourceRollouts) > 0 {
+			isBlueGreenStrategy = sourceRollouts[sourceCluster].Spec.Strategy.BlueGreen != nil && sourceRollouts[sourceCluster].Spec.Strategy.BlueGreen.PreviewService != ""
+		}
+
 		if len(sourceDeployments) > 0 {
 			meshPorts = GetMeshPorts(sourceCluster, serviceInstance, sourceDeployments[sourceCluster])
-		} else {
+		} else if !isBlueGreenStrategy {
 			meshPorts = GetMeshPortsForRollout(sourceCluster, serviceInstance, sourceRollouts[sourceCluster])
 		}
-
 		for key, serviceEntry := range serviceEntries {
 			if len(serviceEntry.Endpoints) == 0 {
 				AddServiceEntriesWithDr(remoteRegistry.AdmiralCache, map[string]string{sourceCluster: sourceCluster}, remoteRegistry.RemoteControllers,
@@ -147,8 +154,31 @@ func modifyServiceEntryForNewServiceOrPod(event admiral.EventType, env string, s
 			for _, ep := range serviceEntry.Endpoints {
 				//replace istio ingress-gateway address with local fqdn, note that ingress-gateway can be empty (not provisoned, or is not up)
 				if ep.Address == clusterIngress || ep.Address == "" {
-					// see if we have weighted services (rollouts with canary strategy)
-					if len(weightedServices) > 1 {
+					// Update endpoints with locafqdn for active and preview se of bluegreen rollout
+					if isBlueGreenStrategy {
+						activeServiceName := sourceRollouts[sourceCluster].Spec.Strategy.BlueGreen.ActiveService
+						previewServiceName := sourceRollouts[sourceCluster].Spec.Strategy.BlueGreen.PreviewService
+						oldPorts := ep.Ports
+						if previewService, ok := weightedServices[previewServiceName]; strings.HasPrefix(key, common.GetPreviewHostnamePrefix()+common.Sep) && ok {
+							previewServiceInstance := previewService.Service
+							localFqdn := previewServiceInstance.Name + common.Sep + previewServiceInstance.Namespace + common.DotLocalDomainSuffix
+							cnames[localFqdn] = "1"
+							ep.Address = localFqdn
+							ep.Ports = GetMeshPortsForRollout(sourceCluster, previewServiceInstance, sourceRollouts[sourceCluster])
+						} else if activeService, ok := weightedServices[activeServiceName]; ok {
+							activeServiceInstance := activeService.Service
+							localFqdn := activeServiceInstance.Name + common.Sep + activeServiceInstance.Namespace + common.DotLocalDomainSuffix
+							cnames[localFqdn] = "1"
+							ep.Address = localFqdn
+							ep.Ports = GetMeshPortsForRollout(sourceCluster, activeServiceInstance, sourceRollouts[sourceCluster])
+						}
+						AddServiceEntriesWithDr(remoteRegistry.AdmiralCache, map[string]string{sourceCluster: sourceCluster}, remoteRegistry.RemoteControllers,
+							map[string]*networking.ServiceEntry{key: serviceEntry})
+						//swap it back to use for next iteration
+						ep.Address = clusterIngress
+						ep.Ports = oldPorts
+						// see if we have weighted services (rollouts with canary strategy)
+					} else if len(weightedServices) > 1 {
 						//add one endpoint per each service, may be modify
 						var se = copyServiceEntry(serviceEntry)
 						updateEndpointsForWeightedServices(se, weightedServices, clusterIngress, meshPorts)
@@ -169,7 +199,7 @@ func modifyServiceEntryForNewServiceOrPod(event admiral.EventType, env string, s
 		}
 
 		for _, val := range dependents {
-			remoteRegistry.AdmiralCache.DependencyNamespaceCache.Put(val, serviceInstance.Namespace, localFqdn, map[string]string{cname: "1"})
+			remoteRegistry.AdmiralCache.DependencyNamespaceCache.Put(val, serviceInstance.Namespace, localFqdn, cnames)
 		}
 
 		if common.GetWorkloadSidecarUpdate() == "enabled" {
@@ -570,6 +600,18 @@ func createServiceEntryForRollout(event admiral.EventType, rc *RemoteController,
 
 	san := getSanForRollout(destRollout, workloadIdentityKey)
 
+	if destRollout.Spec.Strategy.BlueGreen != nil && destRollout.Spec.Strategy.BlueGreen.PreviewService != "" {
+		rolloutServices := getServiceForRollout(rc, destRollout)
+		if _, ok := rolloutServices[destRollout.Spec.Strategy.BlueGreen.PreviewService]; ok {
+			previewGlobalFqdn := common.GetPreviewHostnamePrefix() + common.Sep + common.GetCnameForRollout(destRollout, workloadIdentityKey, common.GetHostnameSuffix())
+			previewAddress := getUniqueAddress(admiralCache, previewGlobalFqdn)
+			if len(previewGlobalFqdn) == 0 || len(previewAddress) == 0 {
+				return nil
+			}
+			generateServiceEntry(event, admiralCache, meshPorts, previewGlobalFqdn, rc, serviceEntries, previewAddress, san)
+		}
+	}
+
 	tmpSe := generateServiceEntry(event, admiralCache, meshPorts, globalFqdn, rc, serviceEntries, address, san)
 	return tmpSe
 }