Source file worker_intf.ml

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(** {2 Parameters to build a worker group} *)

(** The name of the group of workers corresponding to an instantiation
    of {!Make}, as well as the name of each worker in that group. *)
module type NAME = sig
  (** The name/path of the worker group *)
  val base : string list

  (** The abstract name of a single worker *)
  type t

  (** Serializer for the introspection RPCs *)
  val encoding : t Data_encoding.t

  (** Pretty printer for displaying the worker name *)
  val pp : Format.formatter -> t -> unit

  val equal : t -> t -> bool
end

module type VIEW = sig
  type view

  val encoding : view Data_encoding.t

  val pp : Format.formatter -> view -> unit
end

(** The type of messages that are fed to the worker's event loop. *)
module type REQUEST = sig
  (** The type of events.
      It is possible to wait for an event to be processed from outside
      the worker using {!push_request_and_wait}. In this case, the
      handler for this event can return a value. The parameter is the
      type of this value. *)
  type ('response, 'error) t

  include VIEW

  (** The projection function from full request to simple views. *)
  val view : ('response, 'error) t -> view
end

(** The (imperative) state of the event loop. *)
module type TYPES = sig
  (** The internal state that is passed to the event handlers. *)
  type state

  (** The parameters provided when launching a new worker. *)
  type parameters
end