Control.Concurrent.Capataz.Internal.Core

This module contains:

• Functions exported on the public API
• High level message handlers of the supervisor thread loop

Documentation

class HasSupervisor a where

Utility typeclass to call public supervision API with types that contain a supervisor (e.g. Capataz record).

Minimal complete definition

getSupervisor

Methods

getSupervisor :: a -> Supervisor

Fetches a supervisor from a record internals.

Instances

HasSupervisor Capataz

Methods

getSupervisor :: Capataz -> Supervisor

HasSupervisor Supervisor

Methods

getSupervisor :: Supervisor -> Supervisor

forkWorker

Arguments

:: HasSupervisor supervisor

=> WorkerOptions

Worker options (restart, name, callbacks, etc)

-> supervisor

Supervisor that supervises the worker

-> IO WorkerId

An identifier that can be used to terminate the Worker

Creates a green thread from an "IO ()" sub-routine. Depending in options defined in the WorkerOptions record, it will automatically restart this sub-routine in case of failures.

See documentation of related functions:

• "buildWorkerOptionsWithDefault"
• "buildWorkerOptions"

forkSupervisor

Arguments

:: HasSupervisor parentSupervisor

=> SupervisorOptions

Supervisor options

-> parentSupervisor

Parent supervisor instance that supervises new supervisor

-> IO Supervisor

A record used to dynamically create and supervise other processes

Creates a green thread which monitors other green threads for failures and restarts them using settings defined on SupervisorOptions.

See documentation of related functions:

• "buildSupervisorOptionsWithDefault"
• "buildSupervisorOptions"

forkCapataz :: Text -> (CapatazOptions -> CapatazOptions) -> IO Capataz

Creates a Capataz record, which holds both a root supervisor and a Teardown to shut down the system. The root supervisor monitors failures on process threads defined with "supervisorProcessSpecList" or created dynamically using "forkWorker" or "forkSupervisor".

terminateProcess :: HasSupervisor supervisor => Text -> ProcessId -> supervisor -> IO Bool

Stops the execution of a green thread being supervised by the given supervisor.

NOTE: If ProcessId maps to a worker that is configured with a Permanent worker restart strategy, the worker green thread will be restarted again.

joinCapatazThread :: Capataz -> IO ()

Joins the thread of the root supervisor of the given capataz system to the current thread.

getSupervisorProcessId :: Supervisor -> ProcessId

Gets the process identifier of a Supervisor; normally used for termination.

getSupervisorAsync :: Supervisor -> Async ()

Gets the Async of a Supervisor thread.

NOTE: There is no way to get the Async value of the root supervisor; this is to avoid error scenarios.

getCapatazTeardown :: Capataz -> Teardown

Gets Teardown record of this capataz system.