'We\'ve received a node state update from a connected client.
:param IClusterStateSource source: Representation of where these
changes were received from.
:param list state_changes: One or more ``IClusterStateChange``
providers representing the state change which has taken place.'

def node_changed(self, source, state_changes):

    self.cluster_state.apply_changes_from_source(source, state_changes)
    self._schedule_broadcast_update()
