add kubelet client for Pod resource info

This change introduces kubelet client to get allocated device
information of a Pod from newly added Kubelet grpc service.
For more information please see:
[kubernetes/kubernetes#70508](kubernetes/kubernetes#70508)

Change-Id: I11e58ccdd52662601f445fa24c7d55c225441efc
Signed-off-by: Abdul Halim <abdul.halim@intel.com>

checkpoint/checkpoint.go

@@ -21,6 +21,7 @@ import (
 
 	"github.com/intel/multus-cni/logging"
 	"github.com/intel/multus-cni/types"
+	v1 "k8s.io/api/core/v1"
 )
 
 const (
@@ -45,22 +46,18 @@ type Data struct {
 	Checksum uint64
 }
 
-type Checkpoint interface {
-	// GetComputeDeviceMap returns an instance of a map of ResourceInfo for a PodID
-	GetComputeDeviceMap(string) (map[string]*types.ResourceInfo, error)
-}
 type checkpoint struct {
 	fileName   string
 	podEntires []PodDevicesEntry
 }
 
 // GetCheckpoint returns an instance of Checkpoint
-func GetCheckpoint() (Checkpoint, error) {
+func GetCheckpoint() (types.ResourceClient, error) {
 	logging.Debugf("GetCheckpoint(): invoked")
 	return getCheckpoint(checkPointfile)
 }
 
-func getCheckpoint(filePath string) (Checkpoint, error) {
+func getCheckpoint(filePath string) (types.ResourceClient, error) {
 	cp := &checkpoint{fileName: filePath}
 	err := cp.getPodEntries()
 	if err != nil {
@@ -89,12 +86,12 @@ func (cp *checkpoint) getPodEntries() error {
 }
 
 // GetComputeDeviceMap returns an instance of a map of ResourceInfo
-func (cp *checkpoint) GetComputeDeviceMap(podID string) (map[string]*types.ResourceInfo, error) {
-
+func (cp *checkpoint) GetPodResourceMap(pod *v1.Pod) (map[string]*types.ResourceInfo, error) {
+	podID := string(pod.UID)
 	resourceMap := make(map[string]*types.ResourceInfo)
 
 	if podID == "" {
-		return nil, logging.Errorf("GetComputeDeviceMap(): invalid Pod cannot be empty")
+		return nil, logging.Errorf("GetPodResourceMap(): invalid Pod cannot be empty")
 	}
 
 	for _, pod := range cp.podEntires {

checkpoint/checkpoint_test.go

@@ -10,6 +10,9 @@ import (
 	"testing"
 
 	"github.com/intel/multus-cni/types"
+	v1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	k8sTypes "k8s.io/apimachinery/pkg/types"
 )
 
 const (
@@ -74,7 +77,7 @@ var _ = BeforeSuite(func() {
 var _ = Describe("Kubelet checkpoint data read operations", func() {
 	Context("Using /tmp/kubelet_internal_checkpoint file", func() {
 		var (
-			cp            Checkpoint
+			cp            types.ResourceClient
 			err           error
 			resourceMap   map[string]*types.ResourceInfo
 			resourceInfo  *types.ResourceInfo
@@ -87,7 +90,15 @@ var _ = Describe("Kubelet checkpoint data read operations", func() {
 		})
 
 		It("should return a ResourceMap instance", func() {
-			rmap, err := cp.GetComputeDeviceMap("970a395d-bb3b-11e8-89df-408d5c537d23")
+			podUID := k8sTypes.UID("970a395d-bb3b-11e8-89df-408d5c537d23")
+			fakePod := &v1.Pod{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "fakePod",
+					Namespace: "podNamespace",
+					UID:       podUID,
+				},
+			}
+			rmap, err := cp.GetPodResourceMap(fakePod)
 			Expect(err).NotTo(HaveOccurred())
 			Expect(rmap).NotTo(BeEmpty())
 			resourceMap = rmap

glide.yaml

@@ -32,5 +32,11 @@ import:
   - kubernetes
   - tools/clientcmd
   - util/retry
+- package: k8s.io/kubernetes
+  version: v1.13.0
+  subpackages:
+  - pkg/kubelet/apis/podresources
+  - pkg/kubelet/apis/podresources/v1alpha1
+  - pkg/kubelet/util
 - package: github.com/vishvananda/netns
 - package: github.com/pkg/errors

k8sclient/k8sclient.go

@@ -31,7 +31,7 @@ import (
 	"github.com/containernetworking/cni/libcni"
 	"github.com/containernetworking/cni/pkg/skel"
 	cnitypes "github.com/containernetworking/cni/pkg/types"
-	"github.com/intel/multus-cni/checkpoint"
+	"github.com/intel/multus-cni/kubeletclient"
 	"github.com/intel/multus-cni/logging"
 	"github.com/intel/multus-cni/types"
 )
@@ -336,7 +336,7 @@ func cniConfigFromNetworkResource(customResource *types.NetworkAttachmentDefinit
 	return config, nil
 }
 
-func getKubernetesDelegate(client KubeClient, net *types.NetworkSelectionElement, confdir string, podID string, resourceMap map[string]*types.ResourceInfo) (*types.DelegateNetConf, map[string]*types.ResourceInfo, error) {
+func getKubernetesDelegate(client KubeClient, net *types.NetworkSelectionElement, confdir string, pod *v1.Pod, resourceMap map[string]*types.ResourceInfo) (*types.DelegateNetConf, map[string]*types.ResourceInfo, error) {
 
 	logging.Debugf("getKubernetesDelegate: %v, %v, %s", client, net, confdir)
 	rawPath := fmt.Sprintf("/apis/k8s.cni.cncf.io/v1/namespaces/%s/network-attachment-definitions/%s", net.Namespace, net.Name)
@@ -353,18 +353,18 @@ func getKubernetesDelegate(client KubeClient, net *types.NetworkSelectionElement
 	// Get resourceName annotation from NetworkAttachmentDefinition
 	deviceID := ""
 	resourceName, ok := customResource.Metadata.Annotations[resourceNameAnnot]
-	if ok && podID != "" {
+	if ok && pod.Name != "" && pod.Namespace != "" {
 		// ResourceName annotation is found; try to get device info from resourceMap
 		logging.Debugf("getKubernetesDelegate: found resourceName annotation : %s", resourceName)
 
 		if resourceMap == nil {
-			checkpoint, err := checkpoint.GetCheckpoint()
+			ck, err := kubeletclient.GetResourceClient()
 			if err != nil {
-				return nil, resourceMap, logging.Errorf("getKubernetesDelegate: failed to get a checkpoint instance: %v", err)
+				return nil, resourceMap, logging.Errorf("getKubernetesDelegate: failed to get a ResourceClient instance: %v", err)
 			}
-			resourceMap, err = checkpoint.GetComputeDeviceMap(podID)
+			resourceMap, err = ck.GetPodResourceMap(pod)
 			if err != nil {
-				return nil, resourceMap, logging.Errorf("getKubernetesDelegate: failed to get resourceMap from kubelet checkpoint file: %v", err)
+				return nil, resourceMap, logging.Errorf("getKubernetesDelegate: failed to get resourceMap from ResourceClient: %v", err)
 			}
 			logging.Debugf("getKubernetesDelegate(): resourceMap instance: %+v", resourceMap)
 		}
@@ -373,7 +373,7 @@ func getKubernetesDelegate(client KubeClient, net *types.NetworkSelectionElement
 		if ok {
 			if idCount := len(entry.DeviceIDs); idCount > 0 && idCount > entry.Index {
 				deviceID = entry.DeviceIDs[entry.Index]
-				logging.Debugf("getKubernetesDelegate: podID: %s deviceID: %s", podID, deviceID)
+				logging.Debugf("getKubernetesDelegate: podName: %s deviceID: %s", pod.Name, deviceID)
 				entry.Index++ // increment Index for next delegate
 			}
 		}
@@ -536,7 +536,6 @@ func GetNetworkDelegates(k8sclient KubeClient, pod *v1.Pod, networks []*types.Ne
 	var delegates []*types.DelegateNetConf
 	defaultNamespace := pod.ObjectMeta.Namespace
 
-	podID := pod.UID
 	for _, net := range networks {
 
 		// The pods namespace (stored as defaultNamespace, does not equal the annotation's target namespace in net.Namespace)
@@ -547,7 +546,7 @@ func GetNetworkDelegates(k8sclient KubeClient, pod *v1.Pod, networks []*types.Ne
 			}
 		}
 
-		delegate, updatedResourceMap, err := getKubernetesDelegate(k8sclient, net, confdir, string(podID), resourceMap)
+		delegate, updatedResourceMap, err := getKubernetesDelegate(k8sclient, net, confdir, pod, resourceMap)
 		if err != nil {
 			return nil, logging.Errorf("GetPodNetwork: failed getting the delegate: %v", err)
 		}
@@ -690,7 +689,7 @@ func tryLoadK8sPodDefaultNetwork(kubeClient KubeClient, pod *v1.Pod, conf *types
 		return nil, logging.Errorf("tryLoadK8sPodDefaultNetwork: more than one default network is specified: %s", netAnnot)
 	}
 
-	delegate, _, err := getKubernetesDelegate(kubeClient, networks[0], conf.ConfDir, "", nil)
+	delegate, _, err := getKubernetesDelegate(kubeClient, networks[0], conf.ConfDir, pod, nil)
 	if err != nil {
 		return nil, logging.Errorf("tryLoadK8sPodDefaultNetwork: failed getting the delegate: %v", err)
 	}