Phase 2 Task 1. Three changes to the embedded base config, plus a test that
reads every one of them back off a RUNNING ActorSystem rather than off the
HOCON text -- the settled idiom here (SplitBrainResolverActivationTests),
because several fragments compete and the losing one still reads correctly in
the file.
- Registers the ClusterClientReceptionist extension. It is not auto-started, so
without this the boundary only listens if some code path happens to call
ClusterClientReceptionist.Get(system) first: "is the boundary up?" would
depend on startup ordering rather than on configuration.
- buffer-size = 0. This is the one genuine behaviour change and it is NOT what
the sister project runs -- they never wrote this section and inherit 1000.
Buffering would replay a DispatchDeployment on reconnect and apply a
deployment the coordinator already sealed as TimedOut, leaving the node on a
configuration the database says failed.
- log-frame-size-exceeding = 32000b. An oversized frame is dropped WITHOUT
tearing down the association: heartbeats keep flowing, the node reports
healthy, and the only symptom is a command that never arrived. Our deploy
notify is payload-free, so this canary should stay quiet.
reconnect-timeout and receptionist.role restate Akka defaults; they are stated
explicitly and pinned because the behaviour is load-bearing, and the comments
say which is which.
One test was VACUOUS on first write: Config.GetInt returns 0 for a missing key,
so the buffering assertion passed before the feature existed -- it could not
distinguish "explicitly 0" from "absent, default 1000 in force". Rewritten to
assert through ClusterClientSettings/ClusterReceptionistSettings, the objects
the client is actually built from. Sabotage-verified after the fix: setting
buffer-size back to 1000 reddens exactly that one test.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW