chore(storageclass): provide switch to toggle storage class creation

[dsharma-dc]

Pull Request template

Why is this PR required? What issue does it fix?:
No bug fix, just a convenience flag is being added.

What this PR does?:
Provides an option in helm chart to toggle storage class creation.

Does this PR require any upgrade changes?:
No
If the changes in this PR are manually verified, list down the scenarios covered::

Any additional information for your reviewer? :
Mention if this PR is part of any design or a continuation of previous PRs

Checklist:

• Fixes Helm chart nfsStorageClass.enabled property is missing #147
• PR Title follows the convention of <type>(<scope>): <subject>
• Has the change log section been updated?
• Commit has unit tests
• Commit has integration tests
• (Optional) Does this PR change require updating NFS-Provisioner Chart? If yes, mention the Helm Chart PR #
• (Optional) Are upgrade changes included in this PR? If not, mention the issue/PR to track:
• (Optional) If documentation changes are required, which issue on https://github.com/openebs/openebs-docs is used to track them:

[dsharma-dc]

Testing

With storage class enabled. Default behaviour.

$ kubectl get sc
NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE
cloud-volumes (default) csi.xxx.cloud Delete WaitForFirstConsumer true 44m
openebs-kernel-nfs openebs.io/nfsrwx Delete Immediate false 37s

With storage class disabled, openebs-kernel-nfs is not created. Able to create new storage class and provision volume.

$ kubectl get sc -n dsnfs
NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE
cloud-volumes (default) csi.xxx.cloud Delete WaitForFirstConsumer true 46m
openebs-rwx-ds openebs.io/nfsrwx Delete Immediate false 5s

dsharma@diwakar-dev:~/work/dynamic-nfs-provisioner/deploy/helm/charts$ kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
ds-nfs-pvc Bound pvc-a901bab2-3046-491b-a1d0-8ebed2963442 256Mi RWX openebs-rwx-ds 5s

$ kubectl get pv
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
pvc-9e0f76a6-1f7f-4989-8511-2f308afc8fc5 10Gi RWO Delete Bound dsnfs/nfs-pvc-a901bab2-3046-491b-a1d0-8ebed2963442 cloud-volumes 8s
pvc-a901bab2-3046-491b-a1d0-8ebed2963442 256Mi RWX Delete Bound default/ds-nfs-pvc openebs-rwx-ds 7s