Breaking changes/Deprecations:

• There are plans to deprecate Volume Expansion "online/offline" capability (moving to online by default, while allowing for offline via the "Volume In Use" error code). These changes are NOT being made in this CSI release (CSI v1.5.x), instead they will most likely be part of a future release (CSI v1.6+). If you depend on "offline/volume expansion" please follow the relevant discussions (e.g. #429, #431, etc.), and read the CSI release notes carefully.

Additions:

• spec (PR #457): [Alpha] Add optional secrets field to NodeExpandVolumeRequest.
• spec (PR #468): [Alpha] Add optional volume_mount_group field to VolumeCapability under new VOLUME_MOUNT_GROUP capability to enable SPs to apply an fsgroup to a volume filesystem during NodeStageVolume or NodePublishVolume operations.
• spec (PR #476): [Alpha] Add two new volume access modes, SINGLE_NODE_SINGLE_WRITER and SINGLE_NODE_MULTI_WRITER, under a new SINGLE_NODE_MULTI_WRITER capability (intended to replace the existing SINGLE_NODE_WRITER access mode).

Clarifications/Corrections/Fixes:

• spec (PR #475): Further relax size limitation for node_id fields from 192 to 256.

Dependencies:

• lib/go (PR #435): Use go modules to pin dependencies. Move to golang v1.16.4.