pekko Enable deserialization of old Akka cluster messages (mixed pekko/akka cluster)

Forming a cluster with Akka nodes requires the deserialization of cluster messages sent by the Akka. This commit fixes the following exception that occurs during deserialization.

[akka://[email protected]:2551] with serializer id [5] and manifest [akka.cluster.InternalClusterAction$InitJoinAck].
java.lang.IllegalArgumentException: Unknown manifest [akka.cluster.InternalClusterAction$InitJoinAck]
    at org.apache.pekko.cluster.protobuf.ClusterMessageSerializer.fromBinary(ClusterMessageSerializer.scala:156)

Dec 10 '24 01:12 sadekmunawar

I have updated https://cwiki.apache.org/confluence/display/PEKKO/Pekko+Akka+Compatibility and include the fact the we only support forming clusters with Akka nodes of version 2.6.5 and above.

Dec 11 '24 12:12 pjfanning

Does that mean we can close this PR?

Jan 10 '25 12:01 raboof

I would prefer not to use this because I think trying to support Akka before v2.6.5 almost certainly will lead to us having to add extra fixes. One that I suspect that we'd need is that we might need to also allow Pekko nodes to optionally send cluster messages that look like the old Akka format and this PR does not address that.

Jan 10 '25 12:01 pjfanning

I would prefer not to use this because I think trying to support Akka before v2.6.5 almost certainly will lead to us having to add extra fixes.

Sounds reasonable to me

Jan 10 '25 12:01 raboof