Polaris Iceberg rest catalog backed by HMS

[metalshanked]

Is your feature request related to a problem? Please describe.

I understand full iceberg rest catalog support (including writes) is on the way.
Is it possible to set a pluggable backend for the catalog (Eg:- like using Hive Metastore for the iceberg rest catalog)?
Something like what can be done with Gravitino or the Tabular iceberg rest images?

A use case would be to reuse an existing Hive Metastore catalog for Iceberg by adding the Polaris Catalog iceberg rest layer in front so that we can switch our compute and query engines to Unity w/ iceberg rest and at the same time legacy apps can directly interface with HMS

Thanks!

Describe the solution you'd like

No response

Describe alternatives you've considered

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Additional context

No response

[eric-maynard]

I believe that this is what the federation proposal calls a "passthrough facade"

[dennishuo]

Right, the Federation feature is expected to add the ability to use Polaris as an Iceberg REST proxy in front of HMS shortly after initially supporting federation to other Iceberg REST catalogs.

Just linking the federation github issue #540 for easy tracking

[poojanilangekar]

I believe what you've requested is addressed in #2355.