feat(zfs-localpv): initial commit

provisioning and deprovisioning of
the volumes on the node where zfs pool
has already been setup. Pool name and the volume
parameters has to be given in storage class
which will be used to provision the volume.

Signed-off-by: Pawan <pawan@mayadata.io>

pkg/builder/kubernetes.go

@@ -0,0 +1,427 @@
+// Copyright © 2019 The OpenEBS 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 builder
+
+import (
+	"encoding/json"
+
+	apis "github.com/openebs/zfs-localpv/pkg/apis/openebs.io/core/v1alpha1"
+	client "github.com/openebs/zfs-localpv/pkg/common/kubernetes/client"
+	clientset "github.com/openebs/zfs-localpv/pkg/generated/clientset/internalclientset"
+	"github.com/pkg/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+// getClientsetFn is a typed function that
+// abstracts fetching of internal clientset
+type getClientsetFn func() (clientset *clientset.Clientset, err error)
+
+// getClientsetFromPathFn is a typed function that
+// abstracts fetching of clientset from kubeConfigPath
+type getClientsetForPathFn func(kubeConfigPath string) (
+	clientset *clientset.Clientset,
+	err error,
+)
+
+// createFn is a typed function that abstracts
+// creating csi volume instance
+type createFn func(
+	cs *clientset.Clientset,
+	upgradeResultObj *apis.ZFSVolume,
+	namespace string,
+) (*apis.ZFSVolume, error)
+
+// getFn is a typed function that abstracts
+// fetching a csi volume instance
+type getFn func(
+	cli *clientset.Clientset,
+	name,
+	namespace string,
+	opts metav1.GetOptions,
+) (*apis.ZFSVolume, error)
+
+// listFn is a typed function that abstracts
+// listing of csi volume instances
+type listFn func(
+	cli *clientset.Clientset,
+	namespace string,
+	opts metav1.ListOptions,
+) (*apis.ZFSVolumeList, error)
+
+// delFn is a typed function that abstracts
+// deleting a csi volume instance
+type delFn func(
+	cli *clientset.Clientset,
+	name,
+	namespace string,
+	opts *metav1.DeleteOptions,
+) error
+
+// updateFn is a typed function that abstracts
+// updating csi volume instance
+type updateFn func(
+	cs *clientset.Clientset,
+	vol *apis.ZFSVolume,
+	namespace string,
+) (*apis.ZFSVolume, error)
+
+// Kubeclient enables kubernetes API operations
+// on csi volume instance
+type Kubeclient struct {
+	// clientset refers to csi volume's
+	// clientset that will be responsible to
+	// make kubernetes API calls
+	clientset *clientset.Clientset
+
+	kubeConfigPath string
+
+	// namespace holds the namespace on which
+	// kubeclient has to operate
+	namespace string
+
+	// functions useful during mocking
+	getClientset        getClientsetFn
+	getClientsetForPath getClientsetForPathFn
+	get                 getFn
+	list                listFn
+	del                 delFn
+	create              createFn
+	update              updateFn
+}
+
+// KubeclientBuildOption defines the abstraction
+// to build a kubeclient instance
+type KubeclientBuildOption func(*Kubeclient)
+
+// defaultGetClientset is the default implementation to
+// get kubernetes clientset instance
+func defaultGetClientset() (clients *clientset.Clientset, err error) {
+
+	config, err := client.GetConfig(client.New())
+	if err != nil {
+		return nil, err
+	}
+
+	return clientset.NewForConfig(config)
+
+}
+
+// defaultGetClientsetForPath is the default implementation to
+// get kubernetes clientset instance based on the given
+// kubeconfig path
+func defaultGetClientsetForPath(
+	kubeConfigPath string,
+) (clients *clientset.Clientset, err error) {
+	config, err := client.GetConfig(
+		client.New(client.WithKubeConfigPath(kubeConfigPath)))
+	if err != nil {
+		return nil, err
+	}
+
+	return clientset.NewForConfig(config)
+}
+
+// defaultGet is the default implementation to get
+// a csi volume instance in kubernetes cluster
+func defaultGet(
+	cli *clientset.Clientset,
+	name, namespace string,
+	opts metav1.GetOptions,
+) (*apis.ZFSVolume, error) {
+	return cli.OpenebsV1alpha1().
+		ZFSVolumes(namespace).
+		Get(name, opts)
+}
+
+// defaultList is the default implementation to list
+// csi volume instances in kubernetes cluster
+func defaultList(
+	cli *clientset.Clientset,
+	namespace string,
+	opts metav1.ListOptions,
+) (*apis.ZFSVolumeList, error) {
+	return cli.OpenebsV1alpha1().
+		ZFSVolumes(namespace).
+		List(opts)
+}
+
+// defaultCreate is the default implementation to delete
+// a csi volume instance in kubernetes cluster
+func defaultDel(
+	cli *clientset.Clientset,
+	name, namespace string,
+	opts *metav1.DeleteOptions,
+) error {
+	deletePropagation := metav1.DeletePropagationForeground
+	opts.PropagationPolicy = &deletePropagation
+	err := cli.OpenebsV1alpha1().
+		ZFSVolumes(namespace).
+		Delete(name, opts)
+	return err
+}
+
+// defaultCreate is the default implementation to create
+// a csi volume instance in kubernetes cluster
+func defaultCreate(
+	cli *clientset.Clientset,
+	vol *apis.ZFSVolume,
+	namespace string,
+) (*apis.ZFSVolume, error) {
+	return cli.OpenebsV1alpha1().
+		ZFSVolumes(namespace).
+		Create(vol)
+}
+
+// defaultUpdate is the default implementation to update
+// a csi volume instance in kubernetes cluster
+func defaultUpdate(
+	cli *clientset.Clientset,
+	vol *apis.ZFSVolume,
+	namespace string,
+) (*apis.ZFSVolume, error) {
+	return cli.OpenebsV1alpha1().
+		ZFSVolumes(namespace).
+		Update(vol)
+}
+
+// withDefaults sets the default options
+// of kubeclient instance
+func (k *Kubeclient) withDefaults() {
+	if k.getClientset == nil {
+		k.getClientset = defaultGetClientset
+	}
+	if k.getClientsetForPath == nil {
+		k.getClientsetForPath = defaultGetClientsetForPath
+	}
+	if k.get == nil {
+		k.get = defaultGet
+	}
+	if k.list == nil {
+		k.list = defaultList
+	}
+	if k.del == nil {
+		k.del = defaultDel
+	}
+	if k.create == nil {
+		k.create = defaultCreate
+	}
+	if k.update == nil {
+		k.update = defaultUpdate
+	}
+}
+
+// WithClientSet sets the kubernetes client against
+// the kubeclient instance
+func WithClientSet(c *clientset.Clientset) KubeclientBuildOption {
+	return func(k *Kubeclient) {
+		k.clientset = c
+	}
+}
+
+// WithNamespace sets the kubernetes client against
+// the provided namespace
+func WithNamespace(namespace string) KubeclientBuildOption {
+	return func(k *Kubeclient) {
+		k.namespace = namespace
+	}
+}
+
+// WithNamespace sets the provided namespace
+// against this Kubeclient instance
+func (k *Kubeclient) WithNamespace(namespace string) *Kubeclient {
+	k.namespace = namespace
+	return k
+}
+
+// WithKubeConfigPath sets the kubernetes client
+// against the provided path
+func WithKubeConfigPath(path string) KubeclientBuildOption {
+	return func(k *Kubeclient) {
+		k.kubeConfigPath = path
+	}
+}
+
+// NewKubeclient returns a new instance of
+// kubeclient meant for csi volume operations
+func NewKubeclient(opts ...KubeclientBuildOption) *Kubeclient {
+	k := &Kubeclient{}
+	for _, o := range opts {
+		o(k)
+	}
+
+	k.withDefaults()
+	return k
+}
+
+func (k *Kubeclient) getClientsetForPathOrDirect() (
+	*clientset.Clientset,
+	error,
+) {
+	if k.kubeConfigPath != "" {
+		return k.getClientsetForPath(k.kubeConfigPath)
+	}
+
+	return k.getClientset()
+}
+
+// getClientOrCached returns either a new instance
+// of kubernetes client or its cached copy
+func (k *Kubeclient) getClientOrCached() (*clientset.Clientset, error) {
+	if k.clientset != nil {
+		return k.clientset, nil
+	}
+
+	c, err := k.getClientsetForPathOrDirect()
+	if err != nil {
+		return nil,
+			errors.Wrapf(
+				err,
+				"failed to get clientset",
+			)
+	}
+
+	k.clientset = c
+	return k.clientset, nil
+}
+
+// Create creates a csi volume instance
+// in kubernetes cluster
+func (k *Kubeclient) Create(vol *apis.ZFSVolume) (*apis.ZFSVolume, error) {
+	if vol == nil {
+		return nil,
+			errors.New(
+				"failed to create csivolume: nil vol object",
+			)
+	}
+	cs, err := k.getClientOrCached()
+	if err != nil {
+		return nil, errors.Wrapf(
+			err,
+			"failed to create csi volume {%s} in namespace {%s}",
+			vol.Name,
+			k.namespace,
+		)
+	}
+
+	return k.create(cs, vol, k.namespace)
+}
+
+// Get returns csi volume object for given name
+func (k *Kubeclient) Get(
+	name string,
+	opts metav1.GetOptions,
+) (*apis.ZFSVolume, error) {
+	if name == "" {
+		return nil,
+			errors.New(
+				"failed to get csi volume: missing csi volume name",
+			)
+	}
+
+	cli, err := k.getClientOrCached()
+	if err != nil {
+		return nil, errors.Wrapf(
+			err,
+			"failed to get csi volume {%s} in namespace {%s}",
+			name,
+			k.namespace,
+		)
+	}
+
+	return k.get(cli, name, k.namespace, opts)
+}
+
+// GetRaw returns csi volume instance
+// in bytes
+func (k *Kubeclient) GetRaw(
+	name string,
+	opts metav1.GetOptions,
+) ([]byte, error) {
+	if name == "" {
+		return nil, errors.New(
+			"failed to get raw csi volume: missing vol name",
+		)
+	}
+	csiv, err := k.Get(name, opts)
+	if err != nil {
+		return nil, errors.Wrapf(
+			err,
+			"failed to get csi volume {%s} in namespace {%s}",
+			name,
+			k.namespace,
+		)
+	}
+
+	return json.Marshal(csiv)
+}
+
+// List returns a list of csi volume
+// instances present in kubernetes cluster
+func (k *Kubeclient) List(opts metav1.ListOptions) (*apis.ZFSVolumeList, error) {
+	cli, err := k.getClientOrCached()
+	if err != nil {
+		return nil, errors.Wrapf(
+			err,
+			"failed to list csi volumes in namespace {%s}",
+			k.namespace,
+		)
+	}
+
+	return k.list(cli, k.namespace, opts)
+}
+
+// Delete deletes the csi volume from
+// kubernetes
+func (k *Kubeclient) Delete(name string) error {
+	if name == "" {
+		return errors.New(
+			"failed to delete csivolume: missing vol name",
+		)
+	}
+	cli, err := k.getClientOrCached()
+	if err != nil {
+		return errors.Wrapf(
+			err,
+			"failed to delete csivolume {%s} in namespace {%s}",
+			name,
+			k.namespace,
+		)
+	}
+
+	return k.del(cli, name, k.namespace, &metav1.DeleteOptions{})
+}
+
+// Update updates this csi volume instance
+// against kubernetes cluster
+func (k *Kubeclient) Update(vol *apis.ZFSVolume) (*apis.ZFSVolume, error) {
+	if vol == nil {
+		return nil,
+			errors.New(
+				"failed to update csivolume: nil vol object",
+			)
+	}
+
+	cs, err := k.getClientOrCached()
+	if err != nil {
+		return nil, errors.Wrapf(
+			err,
+			"failed to update csivolume {%s} in namespace {%s}",
+			vol.Name,
+			vol.Namespace,
+		)
+	}
+
+	return k.update(cs, vol, k.namespace)
+}