Volume populator for ReplicationDestination

[JohnStrunk]

Describe the feature you'd like to have. It should be possible to use the ReplicationDestination object as the dataSourceRef of a PVC to enable easier promotion of the latest replicated image.

What is the value to the end user? (why is it a priority?) Today, users must manually copy the .status.latestImage information into the PVC in order to promote a volume. In addition to being not user friendly, this has an inherent race condition where the replication cycle may replace the Snapshot before it can be properly restored. By using the Data Populator feature, the RD can just be use directly, and it can be left to VolSync to handle the timing issues related to Snapshot promotion.

How will we know we have a good solution? (acceptance criteria)

• Placing a ReplicationDestination reference into the dataSourceRef field of a new PVC will cause the PVC to be provisioned with the contents of the latest replicated data.
• VolSync would be responsible for handling the race between new replications replacing the Snapshot and the Snapshot's restoration into the PVC.

Additional context

[tesshuflower]

/assign @tesshuflower

[tesshuflower]

/close

Released in v0.8.0