package rpc_parallel

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module Worker = Make(T)

The Worker module has specialized functions to spawn workers and run functions on workers.

Parameters

module S : Worker_spec

Signature

type t

A Worker.t type is defined with bin_io so it is possible to create functions that take a worker as an argument.

include Core.Bin_prot.Binable.S with type t := t
include Bin_prot.Binable.S_only_functions with type t := t
val bin_size_t : t Bin_prot.Size.sizer
val bin_write_t : t Bin_prot.Write.writer
val bin_read_t : t Bin_prot.Read.reader
val __bin_read_t__ : (int -> t) Bin_prot.Read.reader

This function only needs implementation if t exposed to be a polymorphic variant. Despite what the type reads, this does *not* produce a function after reading; instead it takes the constructor tag (int) before reading and reads the rest of the variant t afterwards.

val bin_shape_t : Bin_prot.Shape.t
val bin_writer_t : t Bin_prot.Type_class.writer
val bin_reader_t : t Bin_prot.Type_class.reader
val sexp_of_t : t -> Sexplib0.Sexp.t
type worker = t

A type alias to make the Connection signature more readable

val functions : t S.functions

Accessor for the functions implemented by this worker type

val id : t -> Id.t
val rpc_settings : t -> Rpc_settings.t

serve arg will start an Rpc server in process implementing all the functions of the given worker.

module Connection : sig ... end
module Shutdown_on (M : Core.T1) : sig ... end
type 'a with_spawn_args = ?how:How_to_run.t -> ?name:string -> ?env:(string * string) list -> ?connection_timeout:Core.Time.Span.t -> ?cd:string -> on_failure:(Core.Error.t -> unit) -> 'a

The various spawn functions create a new worker process that implements the functions specified in the Worker_spec.

name will be attached to certain error messages and is useful for debugging.

env extends the environment of the spawned worker process.

connection_timeout is used for various internal timeouts. This may need be to increased if the init arg is really large (serialization and deserialization takes more than connection_timeout).

cd changes the current working directory of a spawned worker process.

shutdown_on specifies when a worker should shut itself down.

on_failure exn will be called in the spawning process upon the worker process raising a background exception. All exceptions raised before functions return will be returned to the caller. on_failure will be called in Monitor.current () at the time of this spawn call. The worker initiates shutdown upon sending the exception to the master process.

worker_state_init_arg (below) will be passed to init_worker_state of the given Worker_spec module. This initializes a persistent worker state for all connections to this worker.

val spawn : (?umask:int -> shutdown_on:'a Shutdown_on(Core.Or_error).t -> redirect_stdout:Fd_redirection.t -> redirect_stderr:Fd_redirection.t -> S.Worker_state.init_arg -> 'a) with_spawn_args

The spawned worker process daemonizes. Any initialization errors that wrote to stderr (Rpc_parallel internal initialization, not user initialization code) will be captured and rewritten to the spawning process's stderr with the prefix "WORKER %NAME% STDERR".

redirect_stdout and redirect_stderr specify stdout and stderr of the worker process.

val spawn_exn : (?umask:int -> shutdown_on:'a Shutdown_on(Core.Monad.Ident).t -> redirect_stdout:Fd_redirection.t -> redirect_stderr:Fd_redirection.t -> S.Worker_state.init_arg -> 'a) with_spawn_args
module Spawn_in_foreground_result : sig ... end
val spawn_in_foreground : (shutdown_on:'a Shutdown_on(Spawn_in_foreground_result).t -> S.Worker_state.init_arg -> 'a) with_spawn_args

Similar to spawn but the worker process does not daemonize. If the process was spawned on a remote host, the ssh Process.t is returned.

Remember to call Process.wait on the returned Process.t to avoid a zombie process. Once the process exits, remember to call Writer.close on Process.stdin and Reader.close on Process.stdout and Process.stderr to close the process's stdin/stdout/stderr.

module Spawn_in_foreground_exn_result : sig ... end
val spawn_in_foreground_exn : (shutdown_on:'a Shutdown_on(Spawn_in_foreground_exn_result).t -> S.Worker_state.init_arg -> 'a) with_spawn_args
val shutdown : t -> unit Core.Or_error.t Async.Deferred.t

shutdown attempts to connect to a worker. Upon success, Shutdown.shutdown 0 is run in the worker. If you want strong guarantees that a worker did shutdown, consider using spawn_in_foreground and inspecting the Process.t.

module Deprecated : sig ... end
module For_internal_testing : sig ... end

This module is used for internal testing of the rpc_parallel library.