fix: fixing CNS IP releae for azure CNI in case of managed endpoint s… (#2588)

* fix: fixing CNS IP releae for azure CNI in case of managed endpoint state.

* fix: changing PodInfo Key to InfraContainerID when Mange Endpoint State is enabled.

Author: behzad-mir

Diff for: cns/NetworkContainerContract.go

@@ -180,6 +180,7 @@ type podInfoScheme int
 const (
 	KubernetesPodInfoScheme podInfoScheme = iota
 	InterfaceIDPodInfoScheme
+	InfraIDPodInfoScheme
 )
 
 // PodInfo represents the object that we are providing network for.
@@ -249,11 +250,18 @@ func (p *podInfo) InterfaceID() string {
 // orchestrator pod name and namespace. if the Version is interfaceID, key is
 // composed of the CNI interfaceID, which is generated from the CRI infra
 // container ID and the pod net ns primary interface name.
+// If the version in InfraContainerID then the key is containerID.
 func (p *podInfo) Key() string {
-	if p.Version == InterfaceIDPodInfoScheme {
+	switch p.Version {
+	case InfraIDPodInfoScheme:
+		return p.PodInfraContainerID
+	case InterfaceIDPodInfoScheme:
 		return p.PodInterfaceID
+	case KubernetesPodInfoScheme:
+		return p.PodName + ":" + p.PodNamespace
+	default:
+		return p.PodName + ":" + p.PodNamespace
 	}
-	return p.PodName + ":" + p.PodNamespace
 }
 
 func (p *podInfo) Name() string {

Diff for: cns/restserver/ipam.go

@@ -713,7 +713,7 @@ func (service *HTTPRestService) releaseIPConfigs(podInfo cns.PodInfo) error {
 	service.Lock()
 	defer service.Unlock()
 	ipsToBeReleased := make([]cns.IPConfigurationStatus, 0)
-
+	logger.Printf("[releaseIPConfigs] Releasing pod with key %s", podInfo.Key())
 	for i, ipID := range service.PodIPIDByPodInterfaceKey[podInfo.Key()] {
 		if ipID != "" {
 			if ipconfig, isExist := service.PodIPConfigState[ipID]; isExist {

Diff for: cns/service/main.go

@@ -843,7 +843,7 @@ func main() {
 		// in this case, cns maintains state with containerid as key and so in-memory cache can lookup
 		// and update based on container id.
 		if cnsconfig.ManageEndpointState {
-			cns.GlobalPodInfoScheme = cns.InterfaceIDPodInfoScheme
+			cns.GlobalPodInfoScheme = cns.InfraIDPodInfoScheme
 		}
 
 		logger.Printf("Set GlobalPodInfoScheme %v (InitializeFromCNI=%t)", cns.GlobalPodInfoScheme, cnsconfig.InitializeFromCNI)
@@ -1244,6 +1244,10 @@ func InitializeCRDState(ctx context.Context, httpRestService cns.HTTPService, cn
 		if err = PopulateCNSEndpointState(httpRestServiceImplementation.EndpointStateStore); err != nil {
 			return errors.Wrap(err, "failed to create CNS EndpointState From CNI")
 		}
+		// endpoint state needs tobe loaded in memory so the subsequent Delete calls remove the state and release the IPs.
+		if err = httpRestServiceImplementation.EndpointStateStore.Read(restserver.EndpointStoreKey, &httpRestServiceImplementation.EndpointState); err != nil {
+			return errors.Wrap(err, "failed to restore endpoint state")
+		}
 	}
 
 	var podInfoByIPProvider cns.PodInfoByIPProvider