Hello, I made a PR, https://github.com/apache/beam/pull/25151, to add configurable gRPC channel to the ArtifactRetrievalService stub. We are hosting our external transforms in different environments and we were trying to host them in Google Cloud Run. This requires that the gRPC calls have to use TransportSecurity and also include additional authorization in each call. This was possible to implement for the Expand stub, but not the ArtifactRetrieval stub. I am wondering who are the best people to request reviews for this? This is my naive implementation and am very open to change on how this should be implemented!
Thanks, Sahith
