SwimEx.Protocol (SwimEx v0.1.0)

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SWIM+INF+Susp protocol state machine.

Owns all membership state, the gossip queue, pending ping tracking, and suspicion timers. The Transport process owns the socket; this GenServer drives everything else.

Message flow

Period fires → pick probe target T
  → send ping(seq) to T
  → wait ping_timeout
ping_timeout fires (no direct ack)
  → send ping_req(seq, target=T) to k random nodes
  → wait ping_timeout again (indirect)
indirect_timeout fires (no indirect ack)
  → gossip suspect(T, inc)
  → start suspicion timer
suspicion_timeout fires
  → gossip dead(T, inc)

Acks at any stage cancel the relevant timer and update membership. A suspect node can refute by sending alive(self, inc+1).

Summary

Functions

child_spec(init_arg)

Returns a specification to start this module under a supervisor.

leave(name)

Notifies the cluster that this node is leaving and stops the process.

members(name, opts)

Returns current cluster members.

start_link(opts)

Starts the SWIM protocol GenServer.

subscribe(name, pid)

Subscribes a process to membership events.

unsubscribe(name, pid)

Unsubscribes a process from membership events.

Functions

child_spec(init_arg)

Returns a specification to start this module under a supervisor.

See Supervisor.

leave(name)

@spec leave(GenServer.server()) :: :ok

Notifies the cluster that this node is leaving and stops the process.

members(name, opts)

@spec members(
  GenServer.server(),
  keyword()
) :: [
  {String.t(), :inet.port_number(), String.t(), SwimEx.Membership.status(),
   non_neg_integer()}
]

Returns current cluster members.

start_link(opts)

@spec start_link(keyword()) :: GenServer.on_start()

Starts the SWIM protocol GenServer.

subscribe(name, pid)

@spec subscribe(GenServer.server(), pid()) :: :ok

Subscribes a process to membership events.

unsubscribe(name, pid)

@spec unsubscribe(GenServer.server(), pid()) :: :ok

Unsubscribes a process from membership events.