Need to pass UserCredentials in Create/Delete Image

[rootfs]

Currently storage class doesn't have credentials API, external-provisioner passes everything into Parameters but not into UserCredentials.

This is a problem for certain volumes such as rbd. We currently use parameters to store plaint text secret to get around this issue.

Ideally credentials should still be encoded as a K8S Secret. External provisioner needs a mechanism to get credentials from StorageClass, either through a special parameter, annotation, or new API fields, then passes these credentials into UserCredentials in CreateVolume and DeleteVolume calls.

thanks @sbezverk for his early investigation into this issue

[rootfs]

per http://blog.kubernetes.io/2018/01/introducing-container-storage-interface.html, credentials are not supported in alpha. Closing.