We have an akka 2.6 cluster written in java and there are two roles (named 'manager' and 'executor') in the cluster with distinct functions. Currently it is all akka classic.
We want to move to akka typed, migrating the 'manager' first as it has less actors and a simpler actor hierarchy, and later tackle the 'executor'.
The cluster currently uses extensively classic distributed pub-sub: https://doc.akka.io/libraries/akka-core/2.6/distributed-pub-sub.html. Akka Typed has a new pub-sub: https://doc.akka.io/libraries/akka-core/2.6/typed/distributed-pub-sub.html
Does akka coexistence support distributed pub-sub across nodes that are mixed classic/typed, and can anyone point me to some example code?
All the info on co-existence makes no mention of pub-sub and how you adapt and co-exist.
No the typed distributed pub sub is using completely different internals than the classic pub sub, so there is no way to seamlessly migrate.
It should however be possible, albeit a bit cumbersome, to do a three step roll out upgrade, with a first upgrade having subscribers subscribe both via classic and typed, but still publishing via classic pub-sub APIs, once that is fully rolled out, a second roll switching over to only publish using typed, and a final roll removing classic subscriptions completely.