Draft as needs further design, and a motivating use-case

Is your feature request related to a problem or challenge? Please describe what you are trying to do.

Currently ObjectStore only supports copying files within the current bucket, this is despite most stores having APIs for performing efficient copies across buckets within the same cloud provider.

Describe the solution you'd like

I would like some mechanism to support copying between ObjectStore, that is able to make use of the more efficient APIs where they are possible. I don't have a good idea of how to achieve this, nor a motivating use-case for this functionality.

Describe alternatives you've considered

Additional context