Is there a plan to migrate ModifyVolumeProperties to ControllerModifyVolume？

[huchengze]

Since the ControllerModifyVolume in the CSI Spec is mature, is there a plan to migrate ModifyVolumeProperties to ControllerModifyVolume?
This way, the CSI driver would not need to integrate modify_grpc separately.

[torredil]

Hi @huchengze, the EBS CSI driver supports volume modification through the standardized CSI ControllerModifyVolume RPC: https://github.com/kubernetes-sigs/aws-ebs-csi-driver/blob/master/docs/modify-volume.md

[fengye87]

Hi @torredil , I think this project could be generally useful for CSI driver implementations that would like to support modifying volumes via PVC annotations, especially for legacy Kubernetes versions where there's no VolumeAttributesClass support. But the problem is, I believe volume-modifier is now not calling the CSI spec standard ControllerModifyVolume method. Would it be acceptable to change it? If so, I would be happy to send a PR.

[huchengze]

Hi @torredil , I have submitted a PR to modify volumes using the K8s CSI controller client, and it is compatible with the existing RPC interface. Please take a look whenever you have time.

[torredil]

Thank you for the additional context @fengye87, and the request for review @huchengze.

I've forwarded this proposal to our internal team for consideration and review. We will provide an update directly on this issue as soon as one is available.

[huchengze]

Hi @torredil , I hope you're doing well. I want to check if there are any updates or further developments on this issue. Please let me know if there's any additional information or assistance required from my side to help move this forward. Looking forward to your response.

[torredil]

Hi @fengye87, thanks for following up and for your patience while we reviewed this. I have an update to share:

As you know, Kubernetes now provides a standardized solution for modifying volumes via VolumeAttributesClasses (supported in EBS CSI Driver v1.29.0+). Maintaining a separate modification mechanism alongside this official solution adds potential for regressions and creates a diverging user experience for Modify Volume. Because of this, in the long term we plan to deprecate this project in favor of the official solution.

As such, we will not be expanding the scope of the volume-modifier-for-k8s sidecar by adding new major features, including migrating ModifyVolumeProperties to the ControllerModifyVolume RPC.

We'll publish more information soon to provide specific details and guidance for this transition. Thank you for starting this thread!