So holochain has a websockets implementation in rust which is great…
However as far as I understand it is currently quite simple.
The conductor listens on a websocket port for RPC calls and responds back using the signal mechanism which broadcasts (remote or local) to all clients of a hApp listening.
But imagine you have a holochain conductor (server) hosting many hApps and you want different hApps to get custom (individual or group) signals back. Then you need a publish subscibe pattern. A way to create publish subscriber “topics” such that signals are broadcast only to their relevant client hApps. I believe this feature is in development and look forward to using it.
Currently it seems that the payload of the signal can include differentiating cellID’s so one can filter messages which are not applicable to hApp… however its a workaround and hApp developers should not have to make such filtering in the future. Any news on PubSub work? @thedavidmeister