fix: prevent stale disconnect from marking reconnected broker offline#303
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This pull request addresses a race condition where a rapid disconnect and reconnect of a broker's control channel could leave the broker permanently offline. The fix updates removeConnection to accept and verify the specific *BrokerConnection pointer, ensuring that stale deferred disconnects do not remove newly established connections. Corresponding unit tests have been added to verify this behavior. There are no review comments, and I have no additional feedback to provide.
…ce (#131) The onDisconnect callback previously used separate ReleaseRuntimeBrokerConnection and UpdateRuntimeBrokerHeartbeat calls. When a broker disconnects and reconnects rapidly, the stale disconnect's offline stamp can clobber the new connection's online status because UpdateRuntimeBrokerHeartbeat has no session guard — it unconditionally overwrites status. Provider statuses are also clobbered and never restored by heartbeats, leaving the broker permanently invisible until hub restart. Add ReleaseAndMarkBrokerOffline which atomically clears affinity AND stamps status=offline in a single CAS write. If a concurrent reconnect has already claimed the broker with a new session, the compare fails and the callback is a no-op. Also add a re-check guard before updating provider statuses.
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Summary
removeConnectiongoroutine races with the new connection. It removes the new connection from the map and firesonDisconnect, leavingonlineProviders=0despite a live WebSocket session.removeConnectionnow takes a*BrokerConnectionpointer and only removes the map entry / fires the disconnect callback when the passed connection is still the active one for thatbrokerID. Superseded connections are silently skipped.Fixes issue 131
Test plan
TestControlChannelManager_ReconnectDoesNotTriggerDisconnect— verifies a staleremoveConnectionfrom the old connection does NOT fireonDisconnector remove the new connectionTestControlChannelManager_StaleRemoveAfterReconnect_ThenRealDisconnect— verifies the full lifecycle: stale remove is skipped, then a real disconnect of the current connection fires the callback correctlyTestControlChannelManager_OnDisconnectCallbackand_NilSafeupdated and passingpkg/hub/...test suite passes