Long-term: support different data sources and prefer them over Channel Access

[klauer]

Consider moving the primary data source from EPICS Channel Access (CA) to Kafka or (less preferably) PVAccess.

This sort of consistency issue is just non-existent when you have a single data structure containing all the necessary information to decode an image.

Originally posted but modified by @klauer in #3 (comment)

[ZLLentz]

How do we handle cross-subnet activity with kafka?
We actually already do have PVA running on most of these

[klauer]

Good question. I'm not very knowledgeable about Kafka, but replacing PVAccess with standard protocols where we are able to is, in my opinion, probably a good path forward. I'll ask around out of curiosity.

Fair point that PVA is already deployed - I suppose we should support it regardless.

[ZLLentz]

Oh I absolutely agree, standard protocols are the way to go where possible. This will make the user experience and the developer experience much better.