feat(provisioner): allow using cluster ip for service (#9)

Signed-off-by: kmova <[email protected]>

deploy/kubectl/busybox-openebs-rwx.yaml

@@ -35,7 +35,7 @@ spec:
           command:
             - sh
             - -c
-            - 'while true; do date > /mnt/data/index.html; hostname >> /mnt/data/index.html; sleep $(($RANDOM % 5 + 5)); done'
+            - 'while true; do touch /mnt/data/index.html; date >> /mnt/data/index.html; hostname >> /mnt/data/index.html; sleep $(($RANDOM % 5 + 5)); tail -1 /mnt/data/index.html; done'
           volumeMounts:
             - name: nfs-volume
               mountPath: /mnt/data

deploy/kubectl/openebs-nfs-provisioner.yaml

@@ -117,7 +117,9 @@ spec:
             fieldRef:
               fieldPath: spec.serviceAccountName
         - name: OPENEBS_IO_ENABLE_ANALYTICS
-          value: "false"
+          value: "true"
+        - name: OPENEBS_IO_NFS_SERVER_USE_CLUSTERIP
+          value: "true"
         - name: OPENEBS_IO_INSTALLER_TYPE
           value: "openebs-operator-nfs"
         # LEADER_ELECTION_ENABLED is used to enable/disable leader election. By default
@@ -149,8 +151,8 @@ metadata:
     cas.openebs.io/config: |
       - name: NFSServerType
         value: "kernel"
-      - name: BackendStorageClass
-        value: "openebs-hostpath"
+      #- name: BackendStorageClass
+      #  value: "openebs-hostpath"
 provisioner: openebs.io/nfsrwx
 reclaimPolicy: Delete
 ---

pkg/kubernetes/api/apps/v1/deployment/deployment.go

@@ -334,6 +334,11 @@ func (b *Builder) WithStrategyType(
 	return b
 }
 
+//WithStrategyTypeRecreate sets the strategy field of the deployment as Recreate
+func (b *Builder) WithStrategyTypeRecreate() *Builder {
+	return b.WithStrategyType(appsv1.RecreateDeploymentStrategyType)
+}
+
 // WithPodTemplateSpecBuilder sets the template field of the deployment
 func (b *Builder) WithPodTemplateSpecBuilder(
 	tmplbuilder *templatespec.Builder,

provisioner/env.go

@@ -36,6 +36,10 @@ const (
 	// ProvisionerExportsSC is the environment variable that provides the
 	// default storage class to be used for exports PVC mount used by NFS Server.
 	ProvisionerExportsSC menv.ENVKey = "OPENEBS_IO_EXPORTS_SC"
+
+	// ProvisionerNFSServerUseClusterIP is the environment variable that
+	// allows user to specify if ClusterIP should be used in NFS K8s Service
+	ProvisionerNFSServerUseClusterIP menv.ENVKey = "OPENEBS_IO_NFS_SERVER_USE_CLUSTERIP"
 )
 
 var (

provisioner/helper_kernel_nfs_server.go

@@ -197,6 +197,7 @@ func (p *Provisioner) createDeployment(nfsServerOpts *KernelNFSServerOptions) er
 		WithNamespace(p.namespace).
 		WithLabelsNew(nfsDeployLabelSelector).
 		WithSelectorMatchLabelsNew(nfsDeployLabelSelector).
+		WithStrategyTypeRecreate().
 		WithPodTemplateSpecBuilder(
 			pts.NewBuilder().
 				WithLabelsNew(nfsDeployLabelSelector).
@@ -420,6 +421,18 @@ func (p *Provisioner) getNFSServerAddress(nfsServerOpts *KernelNFSServerOptions)
 		return "", errors.Wrapf(err, "failed to create NFS Server for PVC{%v}", nfsServerOpts.pvName)
 	}
 
+	//Get the NFS Service to extract Cluster IP
+	if p.useClusterIP {
+		//nfsService := nil
+		nfsService, err := service.NewKubeClient().
+			WithNamespace(p.namespace).
+			Get(nfsServerOpts.serviceName, metav1.GetOptions{})
+		if err != nil || nfsService == nil {
+			return "", errors.Wrapf(err, "failed to get NFS Service for PVC{%v}", nfsServerOpts.pvcName)
+		}
+		return nfsService.Spec.ClusterIP, nil
+	}
+
 	// Return the cluster local nfs service ip
 	// <service-name>.<namespace>.svc.cluster.local
 	return nfsServerOpts.serviceName + "." + p.namespace + ".svc.cluster.local", nil

provisioner/provisioner.go

@@ -55,7 +55,7 @@ import (
 //  it with global information used across PV create and delete operations.
 func NewProvisioner(stopCh chan struct{}, kubeClient *clientset.Clientset) (*Provisioner, error) {
 
-	namespace := getOpenEBSNamespace() //menv.Get(menv.OpenEBSNamespace)
+	namespace := getOpenEBSNamespace()
 	if len(strings.TrimSpace(namespace)) == 0 {
 		return nil, fmt.Errorf("Cannot start Provisioner: failed to get namespace")
 	}
@@ -71,6 +71,7 @@ func NewProvisioner(stopCh chan struct{}, kubeClient *clientset.Clientset) (*Pro
 				Value: getDefaultNFSServerType(),
 			},
 		},
+		useClusterIP: menv.Truthy(ProvisionerNFSServerUseClusterIP),
 	}
 	p.getVolumeConfig = p.GetVolumeConfig
 

provisioner/provisioner_kernel_nfs_server.go

@@ -81,6 +81,15 @@ func (p *Provisioner) ProvisionKernalNFSServer(opts pvController.ProvisionOption
 		WithMountOptions(opts.StorageClass.MountOptions).
 		WithNFS(nfsService, "/", false)
 
+	//Note: The nfs server is launched by the nfs-server-alpine.
+	//When "/" is replaced with "/nfsshare", the mount fails.
+	//
+	//Ref: https://github.com/sjiveson/nfs-server-alpine
+	//Due to the fsid=0 parameter set in the /etc/exports file,
+	//there's no need to specify the folder name when mounting from a client.
+	//For example, this works fine even though the folder being mounted and
+	//shared is /nfsshare
+
 	//Build the pvObject
 	pvObj, err := pvObjBuilder.Build()
 

provisioner/types.go

@@ -34,6 +34,8 @@ type Provisioner struct {
 	defaultConfig []mconfig.Config
 	// getVolumeConfig is a reference to a function
 	getVolumeConfig GetVolumeConfigFn
+	//determine if clusterIP or clusterDNS should be used
+	useClusterIP bool
 }
 
 //VolumeConfig struct contains the merged configuration of the PVC