Annotation for opting into backend sharing; Use hash suffix for sharing; Fix resource GC

pkg/cloudprovider/providers/gce/gce_annotations.go

@@ -21,12 +21,17 @@ import "k8s.io/kubernetes/pkg/api/v1"
 type LoadBalancerType string
 
 const (
-	// ServiceAnnotationLoadBalancerType is the annotation used on a service with type LoadBalancer
+	// ServiceAnnotationLoadBalancerType is annotated on a service with type LoadBalancer
 	// dictates what specific kind of GCP LB should be assembled.
 	// Currently, only "internal" is supported.
 	ServiceAnnotationLoadBalancerType = "cloud.google.com/load-balancer-type"
 
 	LBTypeInternal LoadBalancerType = "internal"
+
+	// ServiceAnnotationInternalBackendShare is annotated on a service with "true" when users
+	// want to share GCP Backend Services for a set of internal load balancers.
+	// ALPHA feature - this may be removed in a future release.
+	ServiceAnnotationILBBackendShare = "cloud.google.com/load-balancer-backend-share"
 )
 
 // GetLoadBalancerAnnotationType returns the type of GCP load balancer which should be assembled.
@@ -49,3 +54,12 @@ func GetLoadBalancerAnnotationType(service *v1.Service) (LoadBalancerType, bool)
 		return v, false
 	}
 }
+
+func GetLoadBalancerAnnotationBackendShare(service *v1.Service) bool {
+	l, exists := service.Annotations[ServiceAnnotationILBBackendShare]
+	if exists && l == "true" {
+		return true
+	}
+
+	return false
+}

pkg/cloudprovider/providers/gce/gce_loadbalancer_internal.go

@@ -41,8 +41,8 @@ func (gce *GCECloud) ensureInternalLoadBalancer(clusterName, clusterID string, s
 	ports, protocol := getPortsAndProtocol(svc.Spec.Ports)
 	scheme := schemeInternal
 	loadBalancerName := cloudprovider.GetLoadBalancerName(svc)
-	shared := !v1_service.RequestsOnlyLocalTraffic(svc)
+	sharedBackend := serviceIsShared(svc)
-	backendServiceName := makeBackendServiceName(loadBalancerName, clusterID, shared, scheme, protocol, svc.Spec.SessionAffinity)
+	backendServiceName := makeBackendServiceName(loadBalancerName, clusterID, sharedBackend, scheme, protocol, svc.Spec.SessionAffinity)
 	backendServiceLink := gce.getBackendServiceLink(backendServiceName)
 
 	// Ensure instance groups exist and nodes are assigned to groups
@@ -52,19 +52,26 @@ func (gce *GCECloud) ensureInternalLoadBalancer(clusterName, clusterID string, s
 		return nil, err
 	}
 
+	existingBSName := getNameFromLink(existingFwdRule.BackendService)
+	existingBackendService, err := gce.GetRegionBackendService(existingBSName, gce.region)
+	if err != nil && !isNotFound(err) {
+		return nil, err
+	}
+
 	// Lock the sharedResourceLock to prevent any deletions of shared resources while assembling shared resources here
 	gce.sharedResourceLock.Lock()
 	defer gce.sharedResourceLock.Unlock()
 
 	// Ensure health check for backend service is created
-	// By default, use the node health check endpoint
+	// The health check is shared unless
-	hcName := makeHealthCheckName(loadBalancerName, clusterID, shared)
+	sharedHealthCheck := !v1_service.RequestsOnlyLocalTraffic(svc)
+	hcName := makeHealthCheckName(loadBalancerName, clusterID, sharedHealthCheck)
 	hcPath, hcPort := GetNodesHealthCheckPath(), GetNodesHealthCheckPort()
-	if !shared {
+	if !sharedHealthCheck {
 		// Service requires a special health check, retrieve the OnlyLocal port & path
 		hcPath, hcPort = v1_service.GetServiceHealthCheckPathPort(svc)
 	}
-	hc, err := gce.ensureInternalHealthCheck(hcName, nm, shared, hcPath, hcPort)
+	hc, err := gce.ensureInternalHealthCheck(hcName, nm, sharedHealthCheck, hcPath, hcPort)
 	if err != nil {
 		return nil, err
 	}
@@ -73,7 +80,7 @@ func (gce *GCECloud) ensureInternalLoadBalancer(clusterName, clusterID string, s
 	if gce.OnXPN() {
 		glog.V(2).Infof("ensureInternalLoadBalancer: cluster is on a cross-project network (XPN) network project %v, compute project %v - skipping firewall creation", gce.networkProjectID, gce.projectID)
 	} else {
-		if err = gce.ensureInternalFirewalls(loadBalancerName, clusterID, nm, svc, strconv.Itoa(int(hcPort)), shared, nodes); err != nil {
+		if err = gce.ensureInternalFirewalls(loadBalancerName, clusterID, nm, svc, strconv.Itoa(int(hcPort)), sharedHealthCheck, nodes); err != nil {
 			return nil, err
 		}
 	}
@@ -95,13 +102,16 @@ func (gce *GCECloud) ensureInternalLoadBalancer(clusterName, clusterID string, s
 		expectedFwdRule.Network = gce.networkURL
 	}
 
-	// Delete the previous internal load balancer if necessary
+	fwdRuleDeleted := false
-	fwdRuleDeleted, err := gce.clearExistingInternalLB(loadBalancerName, existingFwdRule, expectedFwdRule, backendServiceName)
+	if !fwdRuleEqual(existingFwdRule, expectedFwdRule) {
-	if err != nil {
+		glog.V(2).Infof("ensureInternalLoadBalancer(%v: deleting existing forwarding rule with IP address %v", loadBalancerName, existingFwdRule.IPAddress)
-		return nil, err
+		if err = gce.DeleteRegionForwardingRule(loadBalancerName, gce.region); err != nil && !isNotFound(err) {
+			return nil, err
+		}
+		fwdRuleDeleted = true
 	}
 
-	bsDescription := makeBackendServiceDescription(nm, shared)
+	bsDescription := makeBackendServiceDescription(nm, sharedBackend)
 	err = gce.ensureInternalBackendService(backendServiceName, bsDescription, svc.Spec.SessionAffinity, scheme, protocol, igLinks, hc.SelfLink)
 	if err != nil {
 		return nil, err
@@ -115,6 +125,11 @@ func (gce *GCECloud) ensureInternalLoadBalancer(clusterName, clusterID string, s
 		}
 	}
 
+	// Delete the previous internal load balancer if necessary
+	if err = gce.clearPreviousInternalResources(loadBalancerName, existingBackendService, backendServiceName, hcName); err != nil {
+		return nil, err
+	}
+
 	// Get the most recent forwarding rule for the new address.
 	existingFwdRule, err = gce.GetRegionForwardingRule(loadBalancerName, gce.region)
 	if err != nil {
@@ -126,39 +141,25 @@ func (gce *GCECloud) ensureInternalLoadBalancer(clusterName, clusterID string, s
 	return status, nil
 }
 
-func (gce *GCECloud) clearExistingInternalLB(loadBalancerName string, existingFwdRule, expectedFwdRule *compute.ForwardingRule, expectedBSName string) (fwdRuleDeleted bool, err error) {
+func (gce *GCECloud) clearPreviousInternalResources(loadBalancerName string, existingBackendService *compute.BackendService, expectedBSName, expectedHCName string) error {
-	if existingFwdRule == nil {
+	if existingBackendService.Name != expectedBSName {
-		return false, nil
+		glog.V(2).Infof("clearPreviousInternalResources(%v): expected backend service %q does not match previous %q - deleting backend service", loadBalancerName, expectedBSName, existingBackendService.Name)
+		if err := gce.teardownInternalBackendService(existingBackendService.Name); err != nil && !isNotFound(err) {
+			glog.Warningf("clearPreviousInternalResources: could not delete old backend service: %v, err: %v", existingBackendService.Name, err)
+		}
 	}
 
-	if !fwdRuleEqual(existingFwdRule, expectedFwdRule) {
+	if len(existingBackendService.HealthChecks) == 1 {
-		glog.V(2).Infof("clearExistingInternalLB(%v: deleting existing forwarding rule with IP address %v", loadBalancerName, existingFwdRule.IPAddress)
+		existingHCName := getNameFromLink(existingBackendService.HealthChecks[0])
-		if err = gce.DeleteRegionForwardingRule(loadBalancerName, gce.region); err != nil && !isNotFound(err) {
+		if existingHCName != expectedHCName {
-			return false, err
+			glog.V(2).Infof("clearPreviousInternalResources(%v): expected health check %q does not match previous %q - deleting health check", loadBalancerName, expectedHCName, existingHCName)
+			if err := gce.teardownInternalHealthCheckAndFirewall(existingHCName); err != nil {
+				glog.Warningf("clearPreviousInternalResources: could not delete existing healthcheck: %v, err: %v", existingHCName, err)
+			}
 		}
-		fwdRuleDeleted = true
 	}
 
-	existingBSName := getNameFromLink(existingFwdRule.BackendService)
+	return nil
-	bs, err := gce.GetRegionBackendService(existingBSName, gce.region)
-	if err == nil {
-		if bs.Name != expectedBSName {
-			glog.V(2).Infof("clearExistingInternalLB(%v): expected backend service %q does not match actual %q - deleting backend service & healthcheck & firewall", loadBalancerName, expectedBSName, bs.Name)
-			// Delete the backend service as well in case it's switching between shared, nonshared, tcp, udp.
-			var existingHCName string
-			if len(bs.HealthChecks) == 1 {
-				existingHCName = getNameFromLink(bs.HealthChecks[0])
-			}
-			if err = gce.teardownInternalBackendResources(existingBSName, existingHCName); err != nil {
-				glog.Warningf("clearExistingInternalLB: could not delete old resources: %v", err)
-			} else {
-				glog.V(2).Infof("clearExistingInternalLB: done deleting old resources")
-			}
-		}
-	} else {
-		glog.Warningf("clearExistingInternalLB(%v): failed to retrieve existing backend service %v", loadBalancerName, existingBSName)
-	}
-	return fwdRuleDeleted, nil
 }
 
 func (gce *GCECloud) updateInternalLoadBalancer(clusterName, clusterID string, svc *v1.Service, nodes []*v1.Node) error {
@@ -175,8 +176,8 @@ func (gce *GCECloud) updateInternalLoadBalancer(clusterName, clusterID string, s
 	_, protocol := getPortsAndProtocol(svc.Spec.Ports)
 	scheme := schemeInternal
 	loadBalancerName := cloudprovider.GetLoadBalancerName(svc)
-	shared := !v1_service.RequestsOnlyLocalTraffic(svc)
+	sharedBackend := serviceIsShared(svc)
-	backendServiceName := makeBackendServiceName(loadBalancerName, clusterID, shared, scheme, protocol, svc.Spec.SessionAffinity)
+	backendServiceName := makeBackendServiceName(loadBalancerName, clusterID, sharedBackend, scheme, protocol, svc.Spec.SessionAffinity)
 	// Ensure the backend service has the proper backend instance-group links
 	return gce.ensureInternalBackendServiceGroups(backendServiceName, igLinks)
 }
@@ -185,29 +186,28 @@ func (gce *GCECloud) ensureInternalLoadBalancerDeleted(clusterName, clusterID st
 	loadBalancerName := cloudprovider.GetLoadBalancerName(svc)
 	_, protocol := getPortsAndProtocol(svc.Spec.Ports)
 	scheme := schemeInternal
-	shared := !v1_service.RequestsOnlyLocalTraffic(svc)
+	sharedBackend := serviceIsShared(svc)
-	var err error
 
 	gce.sharedResourceLock.Lock()
 	defer gce.sharedResourceLock.Unlock()
 
 	glog.V(2).Infof("ensureInternalLoadBalancerDeleted(%v): deleting region internal forwarding rule", loadBalancerName)
-	if err = gce.DeleteRegionForwardingRule(loadBalancerName, gce.region); err != nil && !isNotFound(err) {
+	if err := gce.DeleteRegionForwardingRule(loadBalancerName, gce.region); err != nil && !isNotFound(err) {
 		return err
 	}
 
-	backendServiceName := makeBackendServiceName(loadBalancerName, clusterID, shared, scheme, protocol, svc.Spec.SessionAffinity)
+	backendServiceName := makeBackendServiceName(loadBalancerName, clusterID, sharedBackend, scheme, protocol, svc.Spec.SessionAffinity)
 	glog.V(2).Infof("ensureInternalLoadBalancerDeleted(%v): deleting region backend service %v", loadBalancerName, backendServiceName)
-	if err = gce.DeleteRegionBackendService(backendServiceName, gce.region); err != nil && !isNotFoundOrInUse(err) {
+	if err := gce.DeleteRegionBackendService(backendServiceName, gce.region); err != nil && !isNotFoundOrInUse(err) {
 		return err
 	}
 
 	// Only delete the health check & health check firewall if they aren't being used by another LB.  If we get
 	// an ResourceInuseBy error, then we can skip deleting the firewall.
 	hcInUse := false
-	hcName := makeHealthCheckName(loadBalancerName, clusterID, shared)
+	hcName := makeHealthCheckName(loadBalancerName, clusterID, sharedBackend)
 	glog.V(2).Infof("ensureInternalLoadBalancerDeleted(%v): deleting health check %v", loadBalancerName, hcName)
-	if err = gce.DeleteHealthCheck(hcName); err != nil && !isNotFoundOrInUse(err) {
+	if err := gce.DeleteHealthCheck(hcName); err != nil && !isNotFoundOrInUse(err) {
 		return err
 	} else if isInUsedByError(err) {
 		glog.V(2).Infof("ensureInternalLoadBalancerDeleted(%v): healthcheck %v still in use", loadBalancerName, hcName)
@@ -215,7 +215,7 @@ func (gce *GCECloud) ensureInternalLoadBalancerDeleted(clusterName, clusterID st
 	}
 
 	glog.V(2).Infof("ensureInternalLoadBalancerDeleted(%v): deleting firewall for traffic", loadBalancerName)
-	if err = gce.DeleteFirewall(loadBalancerName); err != nil {
+	if err := gce.DeleteFirewall(loadBalancerName); err != nil {
 		return err
 	}
 
@@ -223,48 +223,54 @@ func (gce *GCECloud) ensureInternalLoadBalancerDeleted(clusterName, clusterID st
 		glog.V(2).Infof("ensureInternalLoadBalancerDeleted(%v): skipping firewall for healthcheck", loadBalancerName)
 	} else {
 		glog.V(2).Infof("ensureInternalLoadBalancerDeleted(%v): deleting firewall for healthcheck", loadBalancerName)
-		fwHCName := makeHealthCheckFirewallkName(loadBalancerName, clusterID, shared)
+		fwHCName := makeHealthCheckFirewallName(loadBalancerName, clusterID, sharedBackend)
-		if err = gce.DeleteFirewall(fwHCName); err != nil && !isInUsedByError(err) {
+		if err := gce.DeleteFirewall(fwHCName); err != nil && !isInUsedByError(err) {
 			return err
 		}
 	}
 
 	// Try deleting instance groups - expect ResourceInuse error if needed by other LBs
 	igName := makeInstanceGroupName(clusterID)
-	if err = gce.ensureInternalInstanceGroupsDeleted(igName); err != nil && !isInUsedByError(err) {
+	if err := gce.ensureInternalInstanceGroupsDeleted(igName); err != nil && !isInUsedByError(err) {
 		return err
 	}
 
 	return nil
 }
 
-func (gce *GCECloud) teardownInternalBackendResources(bsName, hcName string) error {
+func (gce *GCECloud) teardownInternalBackendService(bsName string) error {
 	if err := gce.DeleteRegionBackendService(bsName, gce.region); err != nil {
 		if isNotFound(err) {
-			glog.V(2).Infof("backend service already deleted: %v, err: %v", bsName, err)
+			glog.V(2).Infof("teardownInternalBackendService(%v): backend service already deleted. err: %v", bsName, err)
+			return nil
 		} else if err != nil && isInUsedByError(err) {
-			glog.V(2).Infof("backend service in use: %v, err: %v", bsName, err)
+			glog.V(2).Infof("teardownInternalBackendService(%v): backend service in use.", bsName)
+			return nil
 		} else {
 			return fmt.Errorf("failed to delete backend service: %v, err: %v", bsName, err)
 		}
 	}
+	glog.V(2).Infof("teardownInternalBackendService(%v): backend service deleted", bsName)
+	return nil
+}
 
-	if hcName == "" {
+func (gce *GCECloud) teardownInternalHealthCheckAndFirewall(hcName string) error {
-		return nil
-	}
 	hcInUse := false
 	if err := gce.DeleteHealthCheck(hcName); err != nil {
 		if isNotFound(err) {
-			glog.V(2).Infof("health check already deleted: %v, err: %v", hcName, err)
+			glog.V(2).Infof("teardownInternalHealthCheckAndFirewall(%v): health check does not exist.", hcName)
+			return nil
 		} else if err != nil && isInUsedByError(err) {
 			hcInUse = true
-			glog.V(2).Infof("health check in use: %v, err: %v", hcName, err)
+			glog.V(2).Infof("teardownInternalHealthCheckAndFirewall(%v): health check in use.", hcName)
+			return nil
 		} else {
 			return fmt.Errorf("failed to delete health check: %v, err: %v", hcName, err)
 		}
 	}
+	glog.V(2).Infof("teardownInternalHealthCheckAndFirewall(%v): health check deleted", hcName)
 
-	hcFirewallName := makeHealthCheckFirewallkNameFromHC(hcName)
+	hcFirewallName := makeHealthCheckFirewallNameFromHC(hcName)
 	if hcInUse {
 		glog.V(2).Infof("skipping deletion of health check firewall: %v", hcFirewallName)
 		return nil
@@ -273,6 +279,7 @@ func (gce *GCECloud) teardownInternalBackendResources(bsName, hcName string) err
 	if err := gce.DeleteFirewall(hcFirewallName); err != nil && !isNotFound(err) {
 		return fmt.Errorf("failed to delete health check firewall: %v, err: %v", hcFirewallName, err)
 	}
+	glog.V(2).Infof("teardownInternalHealthCheckAndFirewall(%v): health check firewall deleted", hcFirewallName)
 	return nil
 }
 
@@ -315,7 +322,7 @@ func (gce *GCECloud) ensureInternalFirewall(fwName, fwDesc string, sourceRanges
 	return gce.UpdateFirewall(expectedFirewall)
 }
 
-func (gce *GCECloud) ensureInternalFirewalls(loadBalancerName, clusterID string, nm types.NamespacedName, svc *v1.Service, healthCheckPort string, shared bool, nodes []*v1.Node) error {
+func (gce *GCECloud) ensureInternalFirewalls(loadBalancerName, clusterID string, nm types.NamespacedName, svc *v1.Service, healthCheckPort string, sharedHealthCheck bool, nodes []*v1.Node) error {
 	// First firewall is for ingress traffic
 	fwDesc := makeFirewallDescription(nm.String(), svc.Spec.LoadBalancerIP)
 	ports, protocol := getPortsAndProtocol(svc.Spec.Ports)
@@ -329,7 +336,7 @@ func (gce *GCECloud) ensureInternalFirewalls(loadBalancerName, clusterID string,
 	}
 
 	// Second firewall is for health checking nodes / services
-	fwHCName := makeHealthCheckFirewallkName(loadBalancerName, clusterID, shared)
+	fwHCName := makeHealthCheckFirewallName(loadBalancerName, clusterID, sharedHealthCheck)
 	hcSrcRanges := LoadBalancerSrcRanges()
 	return gce.ensureInternalFirewall(fwHCName, "", hcSrcRanges, []string{healthCheckPort}, v1.ProtocolTCP, nodes)
 }
@@ -496,6 +503,8 @@ func (gce *GCECloud) ensureInternalBackendService(name, description string, affi
 	}
 
 	glog.V(2).Infof("ensureInternalBackendService: updating backend service %v", name)
+	// Set fingerprint for optimistic locking
+	expectedBS.Fingerprint = bs.Fingerprint
 	if err := gce.UpdateRegionBackendService(expectedBS, gce.region); err != nil {
 		return err
 	}
@@ -503,6 +512,7 @@ func (gce *GCECloud) ensureInternalBackendService(name, description string, affi
 	return nil
 }
 
+// ensureInternalBackendServiceGroups updates backend services if their list of backend instance groups is incorrect.
 func (gce *GCECloud) ensureInternalBackendServiceGroups(name string, igLinks []string) error {
 	glog.V(2).Infof("ensureInternalBackendServiceGroups(%v): checking existing backend service's groups", name)
 	bs, err := gce.GetRegionBackendService(name, gce.region)
@@ -516,7 +526,6 @@ func (gce *GCECloud) ensureInternalBackendServiceGroups(name string, igLinks []s
 	}
 
 	glog.V(2).Infof("ensureInternalBackendServiceGroups: updating backend service %v", name)
-	bs.Backends = backends
 	if err := gce.UpdateRegionBackendService(bs, gce.region); err != nil {
 		return err
 	}
@@ -524,6 +533,10 @@ func (gce *GCECloud) ensureInternalBackendServiceGroups(name string, igLinks []s
 	return nil
 }
 
+func serviceIsShared(svc *v1.Service) bool {
+	return GetLoadBalancerAnnotationBackendShare(svc) && !v1_service.RequestsOnlyLocalTraffic(svc)
+}
+
 func backendsFromGroupLinks(igLinks []string) []*compute.Backend {
 	var backends []*compute.Backend
 	for _, igLink := range igLinks {

pkg/cloudprovider/providers/gce/gce_loadbalancer_naming.go

@@ -17,6 +17,8 @@ limitations under the License.
 package gce
 
 import (
+	"crypto/sha1"
+	"encoding/hex"
 	"fmt"
 	"strings"
 
@@ -33,15 +35,16 @@ func makeInstanceGroupName(clusterID string) string {
 
 func makeBackendServiceName(loadBalancerName, clusterID string, shared bool, scheme lbScheme, protocol v1.Protocol, svcAffinity v1.ServiceAffinity) string {
 	if shared {
-		affinity := ""
+		hash := sha1.New()
-		switch svcAffinity {
-		case v1.ServiceAffinityClientIP:
-			affinity = "clientip"
-		default:
-			affinity = "noaffinity"
-		}
 
-		return fmt.Sprintf("k8s-%s-%s-%s-%s", clusterID, strings.ToLower(string(scheme)), strings.ToLower(string(protocol)), affinity)
+		// For every non-nil option, hash its value. Currently, only service affinity is relevant.
+		hash.Write([]byte(string(svcAffinity)))
+
+		hashed := hex.EncodeToString(hash.Sum(nil))
+		hashed = hashed[:16]
+
+		// 3 + 1 + 16 + 1 + 8 + 1 + 3 + 16
+		return fmt.Sprintf("k8s-%s-%s-%s-nmv1-%s", clusterID, strings.ToLower(string(scheme)), strings.ToLower(string(protocol)), hashed)
 	}
 	return loadBalancerName
 }
@@ -54,11 +57,11 @@ func makeHealthCheckName(loadBalancerName, clusterID string, shared bool) string
 	return loadBalancerName
 }
 
-func makeHealthCheckFirewallkNameFromHC(healthCheckName string) string {
+func makeHealthCheckFirewallNameFromHC(healthCheckName string) string {
 	return healthCheckName + "-hc"
 }
 
-func makeHealthCheckFirewallkName(loadBalancerName, clusterID string, shared bool) string {
+func makeHealthCheckFirewallName(loadBalancerName, clusterID string, shared bool) string {
 	if shared {
 		return fmt.Sprintf("k8s-%s-node-hc", clusterID)
 	}