Cloister (cloister v0.8.0) View Source

Cloister is a consensus helper for clusters.

It is designed to be a configurable drop-in for transparent cluster support.

:otp_app - OTP application this cloister runs for. The default value is :cloister.
:sentry - Required. The way the cloister knows how to build cluster; might be a service name or a node list. E. g. :"cloister.local" or ~w[c1@127.0.0.1 c2@127.0.0.1]a. Default [node()].
:consensus - Required. Number of nodes to consider consensus. The default value is 1.
:listener - Listener to be called when the ring is changed. The default value is Cloister.Listener.Default.
:additional_modules - Additional modules to include into Cloister.Manager’s supervision tree.
:ring - The name of the HashRing to be used. If set, the HashRing is assumed to be managed externally.
:manager - Set of options to configure Cloister.Manager when started in a supervision tree.
- :name - Name of the Manager process.
- :state - The parameters to configure the Manager ouside of Cloister application.
  - :otp_app - Required.
  - :additional_modules
:monitor_opts - Fine Cloister.Monitor’s tuning.
- :name - Required. Name of the Monitor process.
:loopback? - Use loopback interface in FQ node name? The default value is false.
:magic? - When false, allows to avoid node reinitialization The default value is true.

Link to this section Summary

Returns a specification to start this module under a supervisor.

Returns true if the hashring points to this node for the term given, false otherwise

ring()

Returns the ring from current node cloister monitor state

state()

Returns who would be chosen by a hash ring for the term in the group given

Returns a specification to start this module under a supervisor.

mine?(term :: any()) :: boolean() | {:error, :no_such_ring}

Returns true if the hashring points to this node for the term given, false otherwise

ring() :: atom()

Returns the ring from current node cloister monitor state

whois(group :: atom(), term :: any()) ::
  node()
  | {:error, {:invalid_ring, :no_nodes}}
  | {:error, {:not_our_ring, atom()}}

Returns who would be chosen by a hash ring for the term in the group given