vendor/k8s.io/kubernetes/pkg/cloudprovider/providers/vsphere/nodemanager.go - cloudstack-kubernetes-provider - Git at Google

 /*
 Copyright 2016 The Kubernetes Authors.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 */

 package vsphere

 import (
 	"context"
 	"fmt"
 	"strings"
 	"sync"

 	"k8s.io/api/core/v1"
 	k8stypes "k8s.io/apimachinery/pkg/types"
 	"k8s.io/klog"
 	"k8s.io/kubernetes/pkg/cloudprovider/providers/vsphere/vclib"
 )

 // Stores info about the kubernetes node
 type NodeInfo struct {
 	dataCenter *vclib.Datacenter
 	vm         *vclib.VirtualMachine
 	vcServer   string
 	vmUUID     string
 }

 type NodeManager struct {
 	// TODO: replace map with concurrent map when k8s supports go v1.9

 	// Maps the VC server to VSphereInstance
 	vsphereInstanceMap map[string]*VSphereInstance
 	// Maps node name to node info.
 	nodeInfoMap map[string]*NodeInfo
 	// Maps node name to node structure
 	registeredNodes map[string]*v1.Node
 	//CredentialsManager
 	credentialManager *SecretCredentialManager

 	// Mutexes
 	registeredNodesLock   sync.RWMutex
 	nodeInfoLock          sync.RWMutex
 	credentialManagerLock sync.Mutex
 }

 type NodeDetails struct {
 	NodeName string
 	vm       *vclib.VirtualMachine
 	VMUUID   string
 }

 // TODO: Make it configurable in vsphere.conf
 const (
 	POOL_SIZE  = 8
 	QUEUE_SIZE = POOL_SIZE * 10
 )

 func (nm *NodeManager) DiscoverNode(node *v1.Node) error {
 	type VmSearch struct {
 		vc         string
 		datacenter *vclib.Datacenter
 	}

 	var mutex = &sync.Mutex{}
 	var globalErrMutex = &sync.Mutex{}
 	var queueChannel chan *VmSearch
 	var wg sync.WaitGroup
 	var globalErr *error

 	queueChannel = make(chan *VmSearch, QUEUE_SIZE)
 	nodeUUID, err := GetNodeUUID(node)
 	if err != nil {
 		klog.Errorf("Node Discovery failed to get node uuid for node %s with error: %v", node.Name, err)
 		return err
 	}

 	klog.V(4).Infof("Discovering node %s with uuid %s", node.ObjectMeta.Name, nodeUUID)

 	vmFound := false
 	globalErr = nil

 	setGlobalErr := func(err error) {
 		globalErrMutex.Lock()
 		globalErr = &err
 		globalErrMutex.Unlock()
 	}

 	setVMFound := func(found bool) {
 		mutex.Lock()
 		vmFound = found
 		mutex.Unlock()
 	}

 	getVMFound := func() bool {
 		mutex.Lock()
 		found := vmFound
 		mutex.Unlock()
 		return found
 	}

 	go func() {
 		var datacenterObjs []*vclib.Datacenter
 		for vc, vsi := range nm.vsphereInstanceMap {

 			found := getVMFound()
 			if found == true {
 				break
 			}

 			// Create context
 			ctx, cancel := context.WithCancel(context.Background())
 			defer cancel()

 			err := nm.vcConnect(ctx, vsi)
 			if err != nil {
 				klog.V(4).Info("Discovering node error vc:", err)
 				setGlobalErr(err)
 				continue
 			}

 			if vsi.cfg.Datacenters == "" {
 				datacenterObjs, err = vclib.GetAllDatacenter(ctx, vsi.conn)
 				if err != nil {
 					klog.V(4).Info("Discovering node error dc:", err)
 					setGlobalErr(err)
 					continue
 				}
 			} else {
 				datacenters := strings.Split(vsi.cfg.Datacenters, ",")
 				for _, dc := range datacenters {
 					dc = strings.TrimSpace(dc)
 					if dc == "" {
 						continue
 					}
 					datacenterObj, err := vclib.GetDatacenter(ctx, vsi.conn, dc)
 					if err != nil {
 						klog.V(4).Info("Discovering node error dc:", err)
 						setGlobalErr(err)
 						continue
 					}
 					datacenterObjs = append(datacenterObjs, datacenterObj)
 				}
 			}

 			for _, datacenterObj := range datacenterObjs {
 				found := getVMFound()
 				if found == true {
 					break
 				}

 				klog.V(4).Infof("Finding node %s in vc=%s and datacenter=%s", node.Name, vc, datacenterObj.Name())
 				queueChannel <- &VmSearch{
 					vc:         vc,
 					datacenter: datacenterObj,
 				}
 			}
 		}
 		close(queueChannel)
 	}()

 	for i := 0; i < POOL_SIZE; i++ {
 		go func() {
 			for res := range queueChannel {
 				ctx, cancel := context.WithCancel(context.Background())
 				defer cancel()
 				vm, err := res.datacenter.GetVMByUUID(ctx, nodeUUID)
 				if err != nil {
 					klog.V(4).Infof("Error while looking for vm=%+v in vc=%s and datacenter=%s: %v",
 						vm, res.vc, res.datacenter.Name(), err)
 					if err != vclib.ErrNoVMFound {
 						setGlobalErr(err)
 					} else {
 						klog.V(4).Infof("Did not find node %s in vc=%s and datacenter=%s",
 							node.Name, res.vc, res.datacenter.Name())
 					}
 					continue
 				}
 				if vm != nil {
 					klog.V(4).Infof("Found node %s as vm=%+v in vc=%s and datacenter=%s",
 						node.Name, vm, res.vc, res.datacenter.Name())

 					nodeInfo := &NodeInfo{dataCenter: res.datacenter, vm: vm, vcServer: res.vc, vmUUID: nodeUUID}
 					nm.addNodeInfo(node.ObjectMeta.Name, nodeInfo)
 					for range queueChannel {
 					}
 					setVMFound(true)
 					break
 				}
 			}
 			wg.Done()
 		}()
 		wg.Add(1)
 	}
 	wg.Wait()
 	if vmFound {
 		return nil
 	}
 	if globalErr != nil {
 		return *globalErr
 	}

 	klog.V(4).Infof("Discovery Node: %q vm not found", node.Name)
 	return vclib.ErrNoVMFound
 }

 func (nm *NodeManager) RegisterNode(node *v1.Node) error {
 	nm.addNode(node)
 	return nm.DiscoverNode(node)
 }

 func (nm *NodeManager) UnRegisterNode(node *v1.Node) error {
 	nm.removeNode(node)
 	return nil
 }

 func (nm *NodeManager) RediscoverNode(nodeName k8stypes.NodeName) error {
 	node, err := nm.GetNode(nodeName)

 	if err != nil {
 		return err
 	}
 	return nm.DiscoverNode(&node)
 }

 func (nm *NodeManager) GetNode(nodeName k8stypes.NodeName) (v1.Node, error) {
 	nm.registeredNodesLock.RLock()
 	node := nm.registeredNodes[convertToString(nodeName)]
 	nm.registeredNodesLock.RUnlock()
 	if node == nil {
 		return v1.Node{}, vclib.ErrNoVMFound
 	}
 	return *node, nil
 }

 func (nm *NodeManager) addNode(node *v1.Node) {
 	nm.registeredNodesLock.Lock()
 	nm.registeredNodes[node.ObjectMeta.Name] = node
 	nm.registeredNodesLock.Unlock()
 }

 func (nm *NodeManager) removeNode(node *v1.Node) {
 	nm.registeredNodesLock.Lock()
 	delete(nm.registeredNodes, node.ObjectMeta.Name)
 	nm.registeredNodesLock.Unlock()

 	nm.nodeInfoLock.Lock()
 	delete(nm.nodeInfoMap, node.ObjectMeta.Name)
 	nm.nodeInfoLock.Unlock()
 }

 // GetNodeInfo returns a NodeInfo which datacenter, vm and vc server ip address.
 // This method returns an error if it is unable find node VCs and DCs listed in vSphere.conf
 // NodeInfo returned may not be updated to reflect current VM location.
 //
 // This method is a getter but it can cause side-effect of updating NodeInfo object.
 func (nm *NodeManager) GetNodeInfo(nodeName k8stypes.NodeName) (NodeInfo, error) {
 	getNodeInfo := func(nodeName k8stypes.NodeName) *NodeInfo {
 		nm.nodeInfoLock.RLock()
 		nodeInfo := nm.nodeInfoMap[convertToString(nodeName)]
 		nm.nodeInfoLock.RUnlock()
 		return nodeInfo
 	}
 	nodeInfo := getNodeInfo(nodeName)
 	var err error
 	if nodeInfo == nil {
 		// Rediscover node if no NodeInfo found.
 		klog.V(4).Infof("No VM found for node %q. Initiating rediscovery.", convertToString(nodeName))
 		err = nm.RediscoverNode(nodeName)
 		if err != nil {
 			klog.Errorf("Error %q node info for node %q not found", err, convertToString(nodeName))
 			return NodeInfo{}, err
 		}
 		nodeInfo = getNodeInfo(nodeName)
 	} else {
 		// Renew the found NodeInfo to avoid stale vSphere connection.
 		klog.V(4).Infof("Renewing NodeInfo %+v for node %q", nodeInfo, convertToString(nodeName))
 		nodeInfo, err = nm.renewNodeInfo(nodeInfo, true)
 		if err != nil {
 			klog.Errorf("Error %q occurred while renewing NodeInfo for %q", err, convertToString(nodeName))
 			return NodeInfo{}, err
 		}
 		nm.addNodeInfo(convertToString(nodeName), nodeInfo)
 	}
 	return *nodeInfo, nil
 }

 // GetNodeDetails returns NodeDetails for all the discovered nodes.
 //
 // This method is a getter but it can cause side-effect of updating NodeInfo objects.
 func (nm *NodeManager) GetNodeDetails() ([]NodeDetails, error) {
 	nm.registeredNodesLock.Lock()
 	defer nm.registeredNodesLock.Unlock()
 	var nodeDetails []NodeDetails

 	for nodeName, nodeObj := range nm.registeredNodes {
 		nodeInfo, err := nm.GetNodeInfoWithNodeObject(nodeObj)
 		if err != nil {
 			return nil, err
 		}
 		klog.V(4).Infof("Updated NodeInfo %v for node %q.", nodeInfo, nodeName)
 		nodeDetails = append(nodeDetails, NodeDetails{nodeName, nodeInfo.vm, nodeInfo.vmUUID})
 	}
 	return nodeDetails, nil
 }

 func (nm *NodeManager) addNodeInfo(nodeName string, nodeInfo *NodeInfo) {
 	nm.nodeInfoLock.Lock()
 	nm.nodeInfoMap[nodeName] = nodeInfo
 	nm.nodeInfoLock.Unlock()
 }

 func (nm *NodeManager) GetVSphereInstance(nodeName k8stypes.NodeName) (VSphereInstance, error) {
 	nodeInfo, err := nm.GetNodeInfo(nodeName)
 	if err != nil {
 		klog.V(4).Infof("node info for node %q not found", convertToString(nodeName))
 		return VSphereInstance{}, err
 	}
 	vsphereInstance := nm.vsphereInstanceMap[nodeInfo.vcServer]
 	if vsphereInstance == nil {
 		return VSphereInstance{}, fmt.Errorf("vSphereInstance for vc server %q not found while looking for node %q", nodeInfo.vcServer, convertToString(nodeName))
 	}
 	return *vsphereInstance, nil
 }

 // renewNodeInfo renews vSphere connection, VirtualMachine and Datacenter for NodeInfo instance.
 func (nm *NodeManager) renewNodeInfo(nodeInfo *NodeInfo, reconnect bool) (*NodeInfo, error) {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()

 	vsphereInstance := nm.vsphereInstanceMap[nodeInfo.vcServer]
 	if vsphereInstance == nil {
 		err := fmt.Errorf("vSphereInstance for vSphere %q not found while refershing NodeInfo for VM %q", nodeInfo.vcServer, nodeInfo.vm)
 		return nil, err
 	}
 	if reconnect {
 		err := nm.vcConnect(ctx, vsphereInstance)
 		if err != nil {
 			return nil, err
 		}
 	}
 	vm := nodeInfo.vm.RenewVM(vsphereInstance.conn.Client)
 	return &NodeInfo{
 		vm:         &vm,
 		dataCenter: vm.Datacenter,
 		vcServer:   nodeInfo.vcServer,
 		vmUUID:     nodeInfo.vmUUID,
 	}, nil
 }

 func (nodeInfo *NodeInfo) VM() *vclib.VirtualMachine {
 	if nodeInfo == nil {
 		return nil
 	}
 	return nodeInfo.vm
 }

 // vcConnect connects to vCenter with existing credentials
 // If credentials are invalid:
 // 		1. It will fetch credentials from credentialManager
 //      2. Update the credentials
 //		3. Connects again to vCenter with fetched credentials
 func (nm *NodeManager) vcConnect(ctx context.Context, vsphereInstance *VSphereInstance) error {
 	err := vsphereInstance.conn.Connect(ctx)
 	if err == nil {
 		return nil
 	}

 	credentialManager := nm.CredentialManager()
 	if !vclib.IsInvalidCredentialsError(err) || credentialManager == nil {
 		klog.Errorf("Cannot connect to vCenter with err: %v", err)
 		return err
 	}

 	klog.V(4).Infof("Invalid credentials. Cannot connect to server %q. Fetching credentials from secrets.", vsphereInstance.conn.Hostname)

 	// Get latest credentials from SecretCredentialManager
 	credentials, err := credentialManager.GetCredential(vsphereInstance.conn.Hostname)
 	if err != nil {
 		klog.Errorf("Failed to get credentials from Secret Credential Manager with err: %v", err)
 		return err
 	}
 	vsphereInstance.conn.UpdateCredentials(credentials.User, credentials.Password)
 	return vsphereInstance.conn.Connect(ctx)
 }

 // GetNodeInfoWithNodeObject returns a NodeInfo which datacenter, vm and vc server ip address.
 // This method returns an error if it is unable find node VCs and DCs listed in vSphere.conf
 // NodeInfo returned may not be updated to reflect current VM location.
 //
 // This method is a getter but it can cause side-effect of updating NodeInfo object.
 func (nm *NodeManager) GetNodeInfoWithNodeObject(node *v1.Node) (NodeInfo, error) {
 	nodeName := node.Name
 	getNodeInfo := func(nodeName string) *NodeInfo {
 		nm.nodeInfoLock.RLock()
 		nodeInfo := nm.nodeInfoMap[nodeName]
 		nm.nodeInfoLock.RUnlock()
 		return nodeInfo
 	}
 	nodeInfo := getNodeInfo(nodeName)
 	var err error
 	if nodeInfo == nil {
 		// Rediscover node if no NodeInfo found.
 		klog.V(4).Infof("No VM found for node %q. Initiating rediscovery.", nodeName)
 		err = nm.DiscoverNode(node)
 		if err != nil {
 			klog.Errorf("Error %q node info for node %q not found", err, nodeName)
 			return NodeInfo{}, err
 		}
 		nodeInfo = getNodeInfo(nodeName)
 	} else {
 		// Renew the found NodeInfo to avoid stale vSphere connection.
 		klog.V(4).Infof("Renewing NodeInfo %+v for node %q", nodeInfo, nodeName)
 		nodeInfo, err = nm.renewNodeInfo(nodeInfo, true)
 		if err != nil {
 			klog.Errorf("Error %q occurred while renewing NodeInfo for %q", err, nodeName)
 			return NodeInfo{}, err
 		}
 		nm.addNodeInfo(nodeName, nodeInfo)
 	}
 	return *nodeInfo, nil
 }

 func (nm *NodeManager) CredentialManager() *SecretCredentialManager {
 	nm.credentialManagerLock.Lock()
 	defer nm.credentialManagerLock.Unlock()
 	return nm.credentialManager
 }

 func (nm *NodeManager) UpdateCredentialManager(credentialManager *SecretCredentialManager) {
 	nm.credentialManagerLock.Lock()
 	defer nm.credentialManagerLock.Unlock()
 	nm.credentialManager = credentialManager
 }
	/*
	Copyright 2016 The Kubernetes Authors.

	Licensed under the Apache License, Version 2.0 (the "License");
	you may not use this file except in compliance with the License.
	You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS,
	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
	limitations under the License.
	*/

	package vsphere

	import (
	"context"
	"fmt"
	"strings"
	"sync"

	"k8s.io/api/core/v1"
	k8stypes "k8s.io/apimachinery/pkg/types"
	"k8s.io/klog"
	"k8s.io/kubernetes/pkg/cloudprovider/providers/vsphere/vclib"
	)

	// Stores info about the kubernetes node
	type NodeInfo struct {
	dataCenter *vclib.Datacenter
	vm *vclib.VirtualMachine
	vcServer string
	vmUUID string
	}

	type NodeManager struct {
	// TODO: replace map with concurrent map when k8s supports go v1.9

	// Maps the VC server to VSphereInstance
	vsphereInstanceMap map[string]*VSphereInstance
	// Maps node name to node info.
	nodeInfoMap map[string]*NodeInfo
	// Maps node name to node structure
	registeredNodes map[string]*v1.Node
	//CredentialsManager
	credentialManager *SecretCredentialManager

	// Mutexes
	registeredNodesLock sync.RWMutex
	nodeInfoLock sync.RWMutex
	credentialManagerLock sync.Mutex
	}

	type NodeDetails struct {
	NodeName string
	vm *vclib.VirtualMachine
	VMUUID string
	}

	// TODO: Make it configurable in vsphere.conf
	const (
	POOL_SIZE = 8
	QUEUE_SIZE = POOL_SIZE * 10
	)

	func (nm NodeManager) DiscoverNode(node v1.Node) error {
	type VmSearch struct {
	vc string
	datacenter *vclib.Datacenter
	}

	var mutex = &sync.Mutex{}
	var globalErrMutex = &sync.Mutex{}
	var queueChannel chan *VmSearch
	var wg sync.WaitGroup
	var globalErr *error

	queueChannel = make(chan *VmSearch, QUEUE_SIZE)
	nodeUUID, err := GetNodeUUID(node)
	if err != nil {
	klog.Errorf("Node Discovery failed to get node uuid for node %s with error: %v", node.Name, err)
	return err
	}

	klog.V(4).Infof("Discovering node %s with uuid %s", node.ObjectMeta.Name, nodeUUID)

	vmFound := false
	globalErr = nil

	setGlobalErr := func(err error) {
	globalErrMutex.Lock()
	globalErr = &err
	globalErrMutex.Unlock()
	}

	setVMFound := func(found bool) {
	mutex.Lock()
	vmFound = found
	mutex.Unlock()
	}

	getVMFound := func() bool {
	mutex.Lock()
	found := vmFound
	mutex.Unlock()
	return found
	}

	go func() {
	var datacenterObjs []*vclib.Datacenter
	for vc, vsi := range nm.vsphereInstanceMap {

	found := getVMFound()
	if found == true {
	break
	}

	// Create context
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	err := nm.vcConnect(ctx, vsi)
	if err != nil {
	klog.V(4).Info("Discovering node error vc:", err)
	setGlobalErr(err)
	continue
	}

	if vsi.cfg.Datacenters == "" {
	datacenterObjs, err = vclib.GetAllDatacenter(ctx, vsi.conn)
	if err != nil {
	klog.V(4).Info("Discovering node error dc:", err)
	setGlobalErr(err)
	continue
	}
	} else {
	datacenters := strings.Split(vsi.cfg.Datacenters, ",")
	for _, dc := range datacenters {
	dc = strings.TrimSpace(dc)
	if dc == "" {
	continue
	}
	datacenterObj, err := vclib.GetDatacenter(ctx, vsi.conn, dc)
	if err != nil {
	klog.V(4).Info("Discovering node error dc:", err)
	setGlobalErr(err)
	continue
	}
	datacenterObjs = append(datacenterObjs, datacenterObj)
	}
	}

	for _, datacenterObj := range datacenterObjs {
	found := getVMFound()
	if found == true {
	break
	}

	klog.V(4).Infof("Finding node %s in vc=%s and datacenter=%s", node.Name, vc, datacenterObj.Name())
	queueChannel <- &VmSearch{
	vc: vc,
	datacenter: datacenterObj,
	}
	}
	}
	close(queueChannel)
	}()

	for i := 0; i < POOL_SIZE; i++ {
	go func() {
	for res := range queueChannel {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()
	vm, err := res.datacenter.GetVMByUUID(ctx, nodeUUID)
	if err != nil {
	klog.V(4).Infof("Error while looking for vm=%+v in vc=%s and datacenter=%s: %v",
	vm, res.vc, res.datacenter.Name(), err)
	if err != vclib.ErrNoVMFound {
	setGlobalErr(err)
	} else {
	klog.V(4).Infof("Did not find node %s in vc=%s and datacenter=%s",
	node.Name, res.vc, res.datacenter.Name())
	}
	continue
	}
	if vm != nil {
	klog.V(4).Infof("Found node %s as vm=%+v in vc=%s and datacenter=%s",
	node.Name, vm, res.vc, res.datacenter.Name())

	nodeInfo := &NodeInfo{dataCenter: res.datacenter, vm: vm, vcServer: res.vc, vmUUID: nodeUUID}
	nm.addNodeInfo(node.ObjectMeta.Name, nodeInfo)
	for range queueChannel {
	}
	setVMFound(true)
	break
	}
	}
	wg.Done()
	}()
	wg.Add(1)
	}
	wg.Wait()
	if vmFound {
	return nil
	}
	if globalErr != nil {
	return *globalErr
	}

	klog.V(4).Infof("Discovery Node: %q vm not found", node.Name)
	return vclib.ErrNoVMFound
	}

	func (nm NodeManager) RegisterNode(node v1.Node) error {
	nm.addNode(node)
	return nm.DiscoverNode(node)
	}

	func (nm NodeManager) UnRegisterNode(node v1.Node) error {
	nm.removeNode(node)
	return nil
	}

	func (nm *NodeManager) RediscoverNode(nodeName k8stypes.NodeName) error {
	node, err := nm.GetNode(nodeName)

	if err != nil {
	return err
	}
	return nm.DiscoverNode(&node)
	}

	func (nm *NodeManager) GetNode(nodeName k8stypes.NodeName) (v1.Node, error) {
	nm.registeredNodesLock.RLock()
	node := nm.registeredNodes[convertToString(nodeName)]
	nm.registeredNodesLock.RUnlock()
	if node == nil {
	return v1.Node{}, vclib.ErrNoVMFound
	}
	return *node, nil
	}

	func (nm NodeManager) addNode(node v1.Node) {
	nm.registeredNodesLock.Lock()
	nm.registeredNodes[node.ObjectMeta.Name] = node
	nm.registeredNodesLock.Unlock()
	}

	func (nm NodeManager) removeNode(node v1.Node) {
	nm.registeredNodesLock.Lock()
	delete(nm.registeredNodes, node.ObjectMeta.Name)
	nm.registeredNodesLock.Unlock()

	nm.nodeInfoLock.Lock()
	delete(nm.nodeInfoMap, node.ObjectMeta.Name)
	nm.nodeInfoLock.Unlock()
	}

	// GetNodeInfo returns a NodeInfo which datacenter, vm and vc server ip address.
	// This method returns an error if it is unable find node VCs and DCs listed in vSphere.conf
	// NodeInfo returned may not be updated to reflect current VM location.
	//
	// This method is a getter but it can cause side-effect of updating NodeInfo object.
	func (nm *NodeManager) GetNodeInfo(nodeName k8stypes.NodeName) (NodeInfo, error) {
	getNodeInfo := func(nodeName k8stypes.NodeName) *NodeInfo {
	nm.nodeInfoLock.RLock()
	nodeInfo := nm.nodeInfoMap[convertToString(nodeName)]
	nm.nodeInfoLock.RUnlock()
	return nodeInfo
	}
	nodeInfo := getNodeInfo(nodeName)
	var err error
	if nodeInfo == nil {
	// Rediscover node if no NodeInfo found.
	klog.V(4).Infof("No VM found for node %q. Initiating rediscovery.", convertToString(nodeName))
	err = nm.RediscoverNode(nodeName)
	if err != nil {
	klog.Errorf("Error %q node info for node %q not found", err, convertToString(nodeName))
	return NodeInfo{}, err
	}
	nodeInfo = getNodeInfo(nodeName)
	} else {
	// Renew the found NodeInfo to avoid stale vSphere connection.
	klog.V(4).Infof("Renewing NodeInfo %+v for node %q", nodeInfo, convertToString(nodeName))
	nodeInfo, err = nm.renewNodeInfo(nodeInfo, true)
	if err != nil {
	klog.Errorf("Error %q occurred while renewing NodeInfo for %q", err, convertToString(nodeName))
	return NodeInfo{}, err
	}
	nm.addNodeInfo(convertToString(nodeName), nodeInfo)
	}
	return *nodeInfo, nil
	}

	// GetNodeDetails returns NodeDetails for all the discovered nodes.
	//
	// This method is a getter but it can cause side-effect of updating NodeInfo objects.
	func (nm *NodeManager) GetNodeDetails() ([]NodeDetails, error) {
	nm.registeredNodesLock.Lock()
	defer nm.registeredNodesLock.Unlock()
	var nodeDetails []NodeDetails

	for nodeName, nodeObj := range nm.registeredNodes {
	nodeInfo, err := nm.GetNodeInfoWithNodeObject(nodeObj)
	if err != nil {
	return nil, err
	}
	klog.V(4).Infof("Updated NodeInfo %v for node %q.", nodeInfo, nodeName)
	nodeDetails = append(nodeDetails, NodeDetails{nodeName, nodeInfo.vm, nodeInfo.vmUUID})
	}
	return nodeDetails, nil
	}

	func (nm NodeManager) addNodeInfo(nodeName string, nodeInfo NodeInfo) {
	nm.nodeInfoLock.Lock()
	nm.nodeInfoMap[nodeName] = nodeInfo
	nm.nodeInfoLock.Unlock()
	}

	func (nm *NodeManager) GetVSphereInstance(nodeName k8stypes.NodeName) (VSphereInstance, error) {
	nodeInfo, err := nm.GetNodeInfo(nodeName)
	if err != nil {
	klog.V(4).Infof("node info for node %q not found", convertToString(nodeName))
	return VSphereInstance{}, err
	}
	vsphereInstance := nm.vsphereInstanceMap[nodeInfo.vcServer]
	if vsphereInstance == nil {
	return VSphereInstance{}, fmt.Errorf("vSphereInstance for vc server %q not found while looking for node %q", nodeInfo.vcServer, convertToString(nodeName))
	}
	return *vsphereInstance, nil
	}

	// renewNodeInfo renews vSphere connection, VirtualMachine and Datacenter for NodeInfo instance.
	func (nm NodeManager) renewNodeInfo(nodeInfo NodeInfo, reconnect bool) (*NodeInfo, error) {
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	vsphereInstance := nm.vsphereInstanceMap[nodeInfo.vcServer]
	if vsphereInstance == nil {
	err := fmt.Errorf("vSphereInstance for vSphere %q not found while refershing NodeInfo for VM %q", nodeInfo.vcServer, nodeInfo.vm)
	return nil, err
	}
	if reconnect {
	err := nm.vcConnect(ctx, vsphereInstance)
	if err != nil {
	return nil, err
	}
	}
	vm := nodeInfo.vm.RenewVM(vsphereInstance.conn.Client)
	return &NodeInfo{
	vm: &vm,
	dataCenter: vm.Datacenter,
	vcServer: nodeInfo.vcServer,
	vmUUID: nodeInfo.vmUUID,
	}, nil
	}

	func (nodeInfo NodeInfo) VM() vclib.VirtualMachine {
	if nodeInfo == nil {
	return nil
	}
	return nodeInfo.vm
	}

	// vcConnect connects to vCenter with existing credentials
	// If credentials are invalid:
	// 1. It will fetch credentials from credentialManager
	// 2. Update the credentials
	// 3. Connects again to vCenter with fetched credentials
	func (nm NodeManager) vcConnect(ctx context.Context, vsphereInstance VSphereInstance) error {
	err := vsphereInstance.conn.Connect(ctx)
	if err == nil {
	return nil
	}

	credentialManager := nm.CredentialManager()
	if !vclib.IsInvalidCredentialsError(err) \|\| credentialManager == nil {
	klog.Errorf("Cannot connect to vCenter with err: %v", err)
	return err
	}

	klog.V(4).Infof("Invalid credentials. Cannot connect to server %q. Fetching credentials from secrets.", vsphereInstance.conn.Hostname)

	// Get latest credentials from SecretCredentialManager
	credentials, err := credentialManager.GetCredential(vsphereInstance.conn.Hostname)
	if err != nil {
	klog.Errorf("Failed to get credentials from Secret Credential Manager with err: %v", err)
	return err
	}
	vsphereInstance.conn.UpdateCredentials(credentials.User, credentials.Password)
	return vsphereInstance.conn.Connect(ctx)
	}

	// GetNodeInfoWithNodeObject returns a NodeInfo which datacenter, vm and vc server ip address.
	// This method returns an error if it is unable find node VCs and DCs listed in vSphere.conf
	// NodeInfo returned may not be updated to reflect current VM location.
	//
	// This method is a getter but it can cause side-effect of updating NodeInfo object.
	func (nm NodeManager) GetNodeInfoWithNodeObject(node v1.Node) (NodeInfo, error) {
	nodeName := node.Name
	getNodeInfo := func(nodeName string) *NodeInfo {
	nm.nodeInfoLock.RLock()
	nodeInfo := nm.nodeInfoMap[nodeName]
	nm.nodeInfoLock.RUnlock()
	return nodeInfo
	}
	nodeInfo := getNodeInfo(nodeName)
	var err error
	if nodeInfo == nil {
	// Rediscover node if no NodeInfo found.
	klog.V(4).Infof("No VM found for node %q. Initiating rediscovery.", nodeName)
	err = nm.DiscoverNode(node)
	if err != nil {
	klog.Errorf("Error %q node info for node %q not found", err, nodeName)
	return NodeInfo{}, err
	}
	nodeInfo = getNodeInfo(nodeName)
	} else {
	// Renew the found NodeInfo to avoid stale vSphere connection.
	klog.V(4).Infof("Renewing NodeInfo %+v for node %q", nodeInfo, nodeName)
	nodeInfo, err = nm.renewNodeInfo(nodeInfo, true)
	if err != nil {
	klog.Errorf("Error %q occurred while renewing NodeInfo for %q", err, nodeName)
	return NodeInfo{}, err
	}
	nm.addNodeInfo(nodeName, nodeInfo)
	}
	return *nodeInfo, nil
	}

	func (nm NodeManager) CredentialManager() SecretCredentialManager {
	nm.credentialManagerLock.Lock()
	defer nm.credentialManagerLock.Unlock()
	return nm.credentialManager
	}

	func (nm NodeManager) UpdateCredentialManager(credentialManager SecretCredentialManager) {
	nm.credentialManagerLock.Lock()
	defer nm.credentialManagerLock.Unlock()
	nm.credentialManager = credentialManager
	}