mirror of
https://github.com/mudler/LocalAI.git
synced 2026-09-12 22:33:54 -04:00
PostgreSQL holds undelivered notifications in a queue it shares with every session on the server, and it kills a listener that stops draining. Two failure modes follow, and both are silent: a carrier that blocked on a slow resolver would lose its connection and with it every later broadcast, and a carrier that reconnected without re-registering would be connected and deaf. The receive and dispatch halves were already separate. What was missing is everything around them. The listener path moves into listener.go and gains a carrier-level Dropped() so a replica that is behind can be seen; the queue depth and the spill retention become Config fields with exported defaults; the LISTEN session gets an application_name so an operator can count listeners in pg_stat_activity and a spec can drop exactly one of them; and OnReconnect fires after the re-LISTEN, on a goroutine of its own, because a callback re-hydrates from a database and must never run on the path whose only job is to drain. That callback is reached through an optional interface assertion, so deleting its invocation compiles and every adopter silently stops converging. The spec is the only guard, and it is named in a comment at the site. The slow consumer is proved through the transport rather than a seam: an ACCESS EXCLUSIVE lock on bus_messages stalls the resolver's spill SELECT for exactly as long as the spec holds it, and the listener is shown still draining and dropping while it does. The dropped connection is a pg_terminate_backend matched on the carrier's own application name. Neither Dropped nor IsConnected is on messaging.Broadcaster, and a spec asserts that over the interface type. Both are facts about a frontend; the conditions a scheduler acts on are facts about a worker, and no consumer holding the interface can read one as the other. Assisted-by: Claude Opus 5 [claude-code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>