New functions to pre-provision VolumeSnapshot and VolumeSnapshotContent

.gitignore

@@ -6,3 +6,4 @@
 /.vendor
 /bin
 /dist
+**/*.swp

docs/functions.rst

@@ -1332,6 +1332,61 @@ Example:
           snapshotClass: do-block-storage
 
 
+CreateCSISnapshotStatic
+-----------------------
+
+This function creates a pair of CSI ``VolumeSnapshot`` and
+``VolumeSnapshotContent`` resources, assuming that the underlying *real* storage
+volume snapshot already exists. The deletion behavior is defined by the
+``deletionPolicy`` property (``Retain``, ``Delete``) of the snapshot class.
+
+For more information on pre-provisioned volume snapshots and snapshot deletion
+policy, see the Kubernetes `documentation
+<https://kubernetes.io/docs/concepts/storage/volume-snapshots/>`_.
+
+Arguments:
+
+.. csv-table::
+   :header: "Argument", "Required", "Type", "Description"
+   :align: left
+   :widths: 5,5,5,15
+
+   `name`, Yes, `string`, name of the new CSI ``VolumeSnapshot``
+   `namespace`, Yes, `string`, namespace of the new CSI ``VolumeSnapshot``
+   `driver`, Yes, `string`, name of the CSI driver for the new CSI ``VolumeSnapshotContent``
+   `handle`, Yes, `string`, unique identifier of the volume snapshot created on the storage backend used as the source of the new ``VolumeSnapshotContent``
+   `snapshotClass`, Yes, `string`, name of the ``VolumeSnapshotClass`` to use
+
+Outputs:
+
+.. csv-table::
+   :header: "Output", "Type", "Description"
+   :align: left
+   :widths: 5,5,15
+
+   `name`,`string`, name of the new CSI ``VolumeSnapshot``
+   `namespace`, string, namespace of the new CSI ``VolumeSnapshot``
+   `restoreSize`, string, required memory size to restore the volume
+   `snapshotContent`, string, name of the new CSI ``VolumeSnapshotContent``
+
+Example:
+
+.. code-block:: yaml
+  :linenos:
+
+  actions:
+    createStaticSnapshot:
+      phases:
+      - func: CreateCSISnapshotStatic
+        name: createCSISnapshotStatic
+        args:
+          name: volume-snapshot
+          namespace: default
+          snapshotClass: csi-hostpath-snapclass
+          driver: hostpath.csi.k8s.io
+          handle: 7bdd0de3-aaeb-11e8-9aae-0242ac110002
+
+
 RestoreCSISnapshot
 ------------------
 
@@ -1413,6 +1468,36 @@ Example:
           namespace: "{{ .ArtifactsIn.snapshotInfo.KeyValue.namespace }}"
 
 
+DeleteCSISnapshotContent
+------------------------
+
+This function deletes an unbounded ``VolumeSnapshotContent`` resource. It has no
+effect on bounded ``VolumeSnapshotContent`` resources, as they would be
+protected by the CSI controller.
+
+Arguments:
+
+.. csv-table::
+   :header: "Argument", "Required", "Type", "Description"
+   :align: left
+   :widths: 5,5,5,15
+
+   `name`, Yes, `string`, name of the ``VolumeSnapshotContent``
+
+Example:
+
+.. code-block:: yaml
+  :linenos:
+
+  actions:
+    deleteVSC:
+      phases:
+      - func: DeleteCSISnapshotContent
+        name: deleteCSISnapshotContent
+        args:
+          name: "test-snapshot-content-content-dfc8fa67-8b11-4fdf-bf94-928589c2eed8"
+
+
 Registering Functions
 ---------------------
 

docs/spelling_wordlist.txt

@@ -1,6 +1,7 @@
 actionset
 args
 aws
+backend
 backupIdentifier
 backupID
 backupInfo
@@ -29,6 +30,7 @@ param
 params
 PersistentVolumeClaim
 pluggable
+pre
 prepopulated
 Quickstart
 repo

helm/kanister-operator/templates/rbac.yaml

@@ -31,6 +31,7 @@ rules:
   resources:
   - volumesnapshots
   - volumesnapshotcontents
+  - volumesnapshotclasses
   verbs:
   - get
   - create

pkg/function/create_csi_snapshot_static.go

@@ -0,0 +1,160 @@
+// Copyright 2022 The Kanister 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 function
+
+import (
+	"context"
+
+	v1 "github.com/kubernetes-csi/external-snapshotter/client/v4/apis/volumesnapshot/v1"
+
+	kanister "github.com/kanisterio/kanister/pkg"
+	"github.com/kanisterio/kanister/pkg/kube"
+	"github.com/kanisterio/kanister/pkg/kube/snapshot"
+	"github.com/kanisterio/kanister/pkg/param"
+)
+
+func init() {
+	_ = kanister.Register(&createCSISnapshotStaticFunc{})
+}
+
+var (
+	_ kanister.Func = (*createCSISnapshotStaticFunc)(nil)
+)
+
+const (
+	// CreateCSISnapshotStaticFuncName gives the name of the function
+	CreateCSISnapshotStaticFuncName = "CreateCSISnapshotStatic"
+
+	// CreateCSISnapshotStaticNameArg provides name of the new VolumeSnapshot
+	CreateCSISnapshotStaticNameArg = "name"
+
+	// CreateCSISnapshotStaticNamespaceArg specifies the namespace of the new VolumeSnapshot
+	CreateCSISnapshotStaticNamespaceArg = "namespace"
+
+	// CreateCSISnapshotStaticDriverArg specifies the CSI driver used in the new VolumeSnapshotContent
+	CreateCSISnapshotStaticDriverArg = "driver"
+
+	// CreateCSISnapshotStaticSnapshotHandleArg specifies the UID of the backend storage snapshot used in the new VolumeSnapshotContent
+	CreateCSISnapshotStaticSnapshotHandleArg = "snapshotHandle"
+
+	// CreateCSISnapshotStaticSnapshotClassArg specifies the name of the VolumeSnapshotClass
+	CreateCSISnapshotStaticSnapshotClassArg = "snapshotClass"
+
+	// CreateCSISnapshotStaticOutputRestoreSize gives the storage size required for PV/PVC restoration
+	CreateCSISnapshotStaticOutputRestoreSize = "restoreSize"
+
+	// CreateCSISnapshotStaticOutputSnapshotContentName provides the name of dynamically provisioned VolumeSnapshotContent
+	CreateCSISnapshotStaticOutputSnapshotContentName = "snapshotContent"
+)
+
+type createCSISnapshotStaticFunc struct{}
+
+func (*createCSISnapshotStaticFunc) Name() string {
+	return CreateCSISnapshotStaticFuncName
+}
+
+func (*createCSISnapshotStaticFunc) Exec(ctx context.Context, tp param.TemplateParams, args map[string]interface{}) (map[string]interface{}, error) {
+	var (
+		name, namespace                       string
+		driver, snapshotHandle, snapshotClass string
+	)
+
+	if err := Arg(args, CreateCSISnapshotStaticNameArg, &name); err != nil {
+		return nil, err
+	}
+
+	if err := Arg(args, CreateCSISnapshotStaticNamespaceArg, &namespace); err != nil {
+		return nil, err
+	}
+
+	if err := Arg(args, CreateCSISnapshotStaticDriverArg, &driver); err != nil {
+		return nil, err
+	}
+
+	if err := Arg(args, CreateCSISnapshotStaticSnapshotHandleArg, &snapshotHandle); err != nil {
+		return nil, err
+	}
+
+	if err := Arg(args, CreateCSISnapshotStaticSnapshotClassArg, &snapshotClass); err != nil {
+		return nil, err
+	}
+
+	kubeCli, err := kube.NewClient()
+	if err != nil {
+		return nil, err
+	}
+
+	dynCli, err := kube.NewDynamicClient()
+	if err != nil {
+		return nil, err
+	}
+
+	snapshotter, err := snapshot.NewSnapshotter(kubeCli, dynCli)
+	if err != nil {
+		return nil, err
+	}
+
+	// waitForReady is set to true by default because snapshot information is needed as output artifacts
+	waitForReady := true
+	vs, err := createCSISnapshotStatic(ctx, snapshotter, name, namespace, driver, snapshotHandle, snapshotClass, waitForReady)
+	if err != nil {
+		return nil, err
+	}
+
+	return map[string]interface{}{
+		CreateCSISnapshotStaticNameArg:                   name,
+		CreateCSISnapshotStaticNamespaceArg:              namespace,
+		CreateCSISnapshotStaticOutputRestoreSize:         vs.Status.RestoreSize.String(),
+		CreateCSISnapshotStaticOutputSnapshotContentName: vs.Status.BoundVolumeSnapshotContentName,
+	}, nil
+}
+
+func (*createCSISnapshotStaticFunc) RequiredArgs() []string {
+	return []string{
+		CreateCSISnapshotStaticNameArg,
+		CreateCSISnapshotStaticNamespaceArg,
+		CreateCSISnapshotStaticDriverArg,
+		CreateCSISnapshotStaticSnapshotHandleArg,
+		CreateCSISnapshotStaticSnapshotClassArg,
+	}
+}
+
+func (*createCSISnapshotStaticFunc) Arguments() []string {
+	return []string{
+		CreateCSISnapshotStaticNameArg,
+		CreateCSISnapshotStaticNamespaceArg,
+		CreateCSISnapshotStaticDriverArg,
+		CreateCSISnapshotStaticSnapshotHandleArg,
+		CreateCSISnapshotStaticSnapshotClassArg,
+	}
+}
+
+func createCSISnapshotStatic(
+	ctx context.Context,
+	snapshotter snapshot.Snapshotter,
+	name, namespace, driver, snapshotHandle, snapshotClass string,
+	wait bool,
+) (*v1.VolumeSnapshot, error) {
+	source := &snapshot.Source{
+		Handle:                  snapshotHandle,
+		Driver:                  driver,
+		VolumeSnapshotClassName: snapshotClass,
+	}
+	if err := snapshotter.CreateFromSource(ctx, source, name, namespace, wait); err != nil {
+		return nil, err
+	}
+
+	return snapshotter.Get(ctx, name, namespace)
+}