The sibling of Finitomata, but runs transparently in the cluster.

If you want to use a stateful consistent hash ring like libring, implement the behaviour Finitomata.ClusterInfo wrapping calls to it and invoke Finitomata.ClusterInfo.init(Impl) before using Infinitomata.start_fsm/4.

The example of such an implementation for libring (assuming the named ring @ring has been started in the supervision tree) follows.

defmodule MyApp.ClusterInfo do
  @moduledoc false
  @behaviour Finitomata.ClusterInfo

  @impl Finitomata.ClusterInfo
  def nodes(_fini_id), do: HashRing.nodes(@ring) -- [node()]

  @impl Finitomata.ClusterInfo
  def whois(_fini_id, id), do: HashRing.key_to_node(@ring, id)
end

Consistency model

Infinitomata keeps a per-node view of the cluster-wide FSM registry that is eventually consistent. Membership changes are propagated via :pg and reconciled by synch/2, which merges local and remote views (last writer wins per FSM name). A call addressed to an FSM that has not propagated to the local view yet is retried; on a failed remote call the node re-synchronizes and backs off before retrying. Tune the retry behaviour via the :infinitomata_attempts, :infinitomata_poll_interval, :infinitomata_rpc_timeout, :infinitomata_backoff_base, and :infinitomata_backoff_max application config keys.