crew_class_launcher_local: Local process launcher class

In crew: A Distributed Worker Launcher Framework

Local process launcher class

Description

R6 class to launch and manage local process workers.

Details

See crew_launcher_local().

Super class

crew::crew_class_launcher -> crew_class_launcher_local

Active bindings

options_local

See crew_launcher_local().

Methods

Public methods

• crew_class_launcher_local$new()

• crew_class_launcher_local$validate()

• crew_class_launcher_local$launch_worker()

• crew_class_launcher_local$terminate_worker()

Inherited methods

• crew::crew_class_launcher$call()
• crew::crew_class_launcher$crashes()
• crew::crew_class_launcher$launch()
• crew::crew_class_launcher$poll()
• crew::crew_class_launcher$resolve()
• crew::crew_class_launcher$scale()
• crew::crew_class_launcher$set_name()
• crew::crew_class_launcher$settings()
• crew::crew_class_launcher$start()
• crew::crew_class_launcher$terminate()
• crew::crew_class_launcher$terminate_workers()
• crew::crew_class_launcher$update()

---

Method new()

Local launcher constructor.

Usage

crew_class_launcher_local$new(
  name = NULL,
  workers = NULL,
  seconds_interval = NULL,
  seconds_timeout = NULL,
  seconds_launch = NULL,
  seconds_idle = NULL,
  seconds_wall = NULL,
  seconds_exit = NULL,
  tasks_max = NULL,
  tasks_timers = NULL,
  crashes_error = NULL,
  tls = NULL,
  processes = NULL,
  r_arguments = NULL,
  options_metrics = NULL,
  options_local = NULL
)

Arguments

name

See crew_launcher().

workers

See crew_launcher().

seconds_interval

See crew_launcher().

seconds_timeout

See crew_launcher().

seconds_launch

See crew_launcher().

seconds_idle

See crew_launcher().

seconds_wall

See crew_launcher().

seconds_exit

See crew_launcher().

tasks_max

See crew_launcher().

tasks_timers

See crew_launcher().

crashes_error

See crew_launcher().

tls

See crew_launcher().

processes

See crew_launcher().

r_arguments

See crew_launcher().

options_metrics

See crew_launcher_local().

options_local

See crew_launcher_local().

reset_globals

Deprecated. See crew_launcher().

reset_packages

Deprecated. See crew_launcher().

reset_options

Deprecated. See crew_launcher().

garbage_collection

Deprecated. See crew_launcher().

Returns

An R6 object with the local launcher.

Examples

if (identical(Sys.getenv("CREW_EXAMPLES"), "true")) {
client <- crew_client()
client$start()
launcher <- crew_launcher_local(name = client$name)
launcher$start(url = client$url, profile = client$profile)
launcher$launch()
task <- mirai::mirai("result", .compute = client$profile)
mirai::call_mirai(task)
task$data
client$terminate()
}

---

Method validate()

Validate the local launcher.

Usage

crew_class_launcher_local$validate()

Returns

NULL (invisibly).

---

Method launch_worker()

Launch a local process worker which will dial into a socket.

Usage

crew_class_launcher_local$launch_worker(call, name, launcher, worker)

Arguments

call

Character of length 1 with a namespaced call to crew_worker() which will run in the worker and accept tasks.

name

Character of length 1 with a long informative worker name which contains the launcher and worker arguments described below.

launcher

Character of length 1, name of the launcher.

worker

Character string, name of the worker within the launcher.

Details

The call argument is R code that will run to initiate the worker. Together, the launcher, worker, and instance arguments are useful for constructing informative job names.

Returns

A handle object to allow the termination of the worker later on.

---

Method terminate_worker()

Terminate a local process worker.

Usage

crew_class_launcher_local$terminate_worker(handle)

Arguments

handle

A process handle object previously returned by launch_worker().

Returns

A list with the process ID of the worker.

See Also

Other plugin_local: crew_controller_local(), crew_launcher_local()

Examples

if (identical(Sys.getenv("CREW_EXAMPLES"), "true")) {
client <- crew_client()
client$start()
launcher <- crew_launcher_local(name = client$name)
launcher$start(url = client$url, profile = client$profile)
launcher$launch()
task <- mirai::mirai("result", .compute = client$profile)
mirai::call_mirai(task)
task$data
client$terminate()
}

## ------------------------------------------------
## Method `crew_class_launcher_local$new`
## ------------------------------------------------

if (identical(Sys.getenv("CREW_EXAMPLES"), "true")) {
client <- crew_client()
client$start()
launcher <- crew_launcher_local(name = client$name)
launcher$start(url = client$url, profile = client$profile)
launcher$launch()
task <- mirai::mirai("result", .compute = client$profile)
mirai::call_mirai(task)
task$data
client$terminate()
}

crew documentation built on June 9, 2025, 5:09 p.m.