Interface IPool<Worker, Data, Response>

Contract definition for a poolifier pool.

interface IPool<Worker extends IWorker, Data = unknown, Response = unknown> {
    addTaskFunction: (
        name: string,
        fn: TaskFunction<Data, Response> | TaskFunctionObject<Data, Response>,
    ) => Promise<boolean>;
    destroy: () => Promise<void>;
    emitter?: EventEmitterAsyncResource;
    enableTasksQueue: (
        enable: boolean,
        tasksQueueOptions?: TasksQueueOptions,
    ) => void;
    execute: (
        data?: Data,
        name?: string,
        abortSignal?: AbortSignal,
        transferList?: readonly Transferable[],
    ) => Promise<Response>;
    hasTaskFunction: (name: string) => boolean;
    info: PoolInfo;
    listTaskFunctionsProperties: () => TaskFunctionProperties[];
    mapExecute: (
        data: Iterable<Data>,
        name?: string,
        abortSignals?: Iterable<AbortSignal, any, any>,
        transferList?: readonly Transferable[],
    ) => Promise<Response[]>;
    removeTaskFunction: (name: string) => Promise<boolean>;
    setDefaultTaskFunction: (name: string) => Promise<boolean>;
    setTasksQueueOptions: (tasksQueueOptions: TasksQueueOptions) => void;
    setWorkerChoiceStrategy: (
        workerChoiceStrategy:
            | "FAIR_SHARE"
            | "INTERLEAVED_WEIGHTED_ROUND_ROBIN"
            | "LEAST_BUSY"
            | "LEAST_ELU"
            | "LEAST_USED"
            | "ROUND_ROBIN"
            | "WEIGHTED_ROUND_ROBIN",
        workerChoiceStrategyOptions?: WorkerChoiceStrategyOptions,
    ) => void;
    setWorkerChoiceStrategyOptions: (
        workerChoiceStrategyOptions: WorkerChoiceStrategyOptions,
    ) => boolean;
    start: () => void;
    workerNodes: IWorkerNode<Worker, Data>[];
}

Type Parameters

Worker extends IWorker
Type of worker which manages this pool.
Data = unknown
Type of data sent to the worker. This can only be structured-cloneable data.
Response = unknown
Type of execution response. This can only be structured-cloneable data.

Implemented by

AbstractPool

Index

Properties

addTaskFunction destroy emitter? enableTasksQueue execute hasTaskFunction info listTaskFunctionsProperties mapExecute removeTaskFunction setDefaultTaskFunction setTasksQueueOptions setWorkerChoiceStrategy setWorkerChoiceStrategyOptions start workerNodes

Properties

`Readonly`addTaskFunction

addTaskFunction: (
name: string,
fn: TaskFunction<Data, Response> | TaskFunctionObject<Data, Response>,
) => Promise<boolean>

Adds a task function to this pool. If a task function with the same name already exists, it will be overwritten.

Type declaration

- (
  name: string,
  fn: TaskFunction<Data, Response> | TaskFunctionObject<Data, Response>,
  ): Promise<boolean>
- Parameters
  - name: string
    The name of the task function.
  - fn: TaskFunction<Data, Response> | TaskFunctionObject<Data, Response>
    The task function.
  Returns Promise<boolean>
  true if the task function was added, false otherwise.

Throws

https://nodejs.org/api/errors.html#class-typeerror If the name parameter is not a string or an empty string.

Throws

https://nodejs.org/api/errors.html#class-typeerror If the fn parameter is not a function or task function object.

`Readonly`destroy

destroy: () => Promise<void>

Terminates all workers in this pool.

`Optional` `Readonly`emitter

emitter?: EventEmitterAsyncResource

Pool event emitter integrated with async resource. The async tracking tooling identifier is poolifier:<PoolType>-<WorkerType>-pool.

Events that can currently be listened to:

'ready': Emitted when the number of workers created in the pool has reached the minimum size expected and are ready. If the pool is dynamic with a minimum number of workers set to zero, this event is emitted when the pool is started.
'busy': Emitted when the number of workers created in the pool has reached the maximum size expected and are executing concurrently their tasks quota.
'busyEnd': Emitted when the number of workers created in the pool has reached the maximum size expected and are no longer executing concurrently their tasks quota.
'full': Emitted when the pool is dynamic and the number of workers created has reached the maximum size expected.
'fullEnd': Emitted when the pool is dynamic and the number of workers created has no longer reached the maximum size expected.
'empty': Emitted when the pool is dynamic with a minimum number of workers set to zero and the number of workers has reached the minimum size expected.
'destroy': Emitted when the pool is destroyed.
'error': Emitted when an uncaught error occurs.
'taskError': Emitted when an error occurs while executing a task.
'backPressure': Emitted when the number of workers created in the pool has reached the maximum size expected and are back pressured (i.e. their tasks queue is full: queue size >= maximum queue size).
'backPressureEnd': Emitted when the number of workers created in the pool has reached the maximum size expected and are no longer back pressured (i.e. their tasks queue is no longer full: queue size < maximum queue size).

`Readonly`enableTasksQueue

enableTasksQueue: (
enable: boolean,
tasksQueueOptions?: TasksQueueOptions,
) => void

Enables/disables the worker node tasks queue in this pool.

Type declaration

- (enable: boolean, tasksQueueOptions?: TasksQueueOptions): void
- Parameters
  - enable: boolean
    Whether to enable or disable the worker node tasks queue.
  - OptionaltasksQueueOptions: TasksQueueOptions
    The worker node tasks queue options.
  Returns void

`Readonly`execute

execute: (
    data?: Data,
    name?: string,
    abortSignal?: AbortSignal,
    transferList?: readonly Transferable[],
) => Promise<Response>

Executes the specified function in the worker constructor with the task data input parameter.

Type declaration

- (
      data?: Data,
      name?: string,
      abortSignal?: AbortSignal,
      transferList?: readonly Transferable[],
  ): Promise<Response>
- Parameters
  - Optionaldata: Data
    The optional task input data for the specified task function. This can only be structured-cloneable data.
  - Optionalname: string
    The optional name of the task function to execute. If not specified, the default task function will be executed.
  - OptionalabortSignal: AbortSignal
    The optional AbortSignal to abort the task.
  - OptionaltransferList: readonly Transferable[]
    The optional array of transferable objects to transfer ownership of. Ownership of the transferred objects is given to the chosen pool's worker_threads worker and they should not be used in the main thread afterwards.
  Returns Promise<Response>
  Promise with a task function response that will be fulfilled when the task is completed.

`Readonly`hasTaskFunction

hasTaskFunction: (name: string) => boolean

Whether the specified task function exists in this pool.

Type declaration

- (name: string): boolean
- Parameters
  - name: string
    The name of the task function.
  Returns boolean
  true if the task function exists, false otherwise.

`Readonly`info

info: PoolInfo

Pool information.

`Readonly`listTaskFunctionsProperties

listTaskFunctionsProperties: () => TaskFunctionProperties[]

Lists the properties of task functions available in this pool.

Type declaration

- (): TaskFunctionProperties[]
- Returns TaskFunctionProperties[]
  The properties of task functions available in this pool.

`Readonly`mapExecute

mapExecute: (
    data: Iterable<Data>,
    name?: string,
    abortSignals?: Iterable<AbortSignal, any, any>,
    transferList?: readonly Transferable[],
) => Promise<Response[]>

Executes the specified function in the worker constructor with the tasks data iterable input parameter.

Type declaration

- (
      data: Iterable<Data>,
      name?: string,
      abortSignals?: Iterable<AbortSignal, any, any>,
      transferList?: readonly Transferable[],
  ): Promise<Response[]>
- Parameters
  - data: Iterable<Data>
    The tasks iterable input data for the specified task function. This can only be an iterable of structured-cloneable data.
  - Optionalname: string
    The optional name of the task function to execute. If not specified, the default task function will be executed.
  - OptionalabortSignals: Iterable<AbortSignal, any, any>
    The optional iterable of AbortSignal to abort the tasks iterable.
  - OptionaltransferList: readonly Transferable[]
    The optional array of transferable objects to transfer ownership of. Ownership of the transferred objects is given to the chosen pool's worker_threads worker and they should not be used in the main thread afterwards.
  Returns Promise<Response[]>
  Promise with an array of task function responses that will be fulfilled when the tasks are completed.

`Readonly`removeTaskFunction

removeTaskFunction: (name: string) => Promise<boolean>

Removes a task function from this pool.

Type declaration

- (name: string): Promise<boolean>
- Parameters
  - name: string
    The name of the task function.
  Returns Promise<boolean>
  true if the task function was removed, false otherwise.

`Readonly`setDefaultTaskFunction

setDefaultTaskFunction: (name: string) => Promise<boolean>

Sets the default task function in this pool.

Type declaration

- (name: string): Promise<boolean>
- Parameters
  - name: string
    The name of the task function.
  Returns Promise<boolean>
  true if the default task function was set, false otherwise.

`Readonly`setTasksQueueOptions

setTasksQueueOptions: (tasksQueueOptions: TasksQueueOptions) => void

Sets the worker node tasks queue options in this pool.

Type declaration

- (tasksQueueOptions: TasksQueueOptions): void
- Parameters
  - tasksQueueOptions: TasksQueueOptions
    The worker node tasks queue options.
  Returns void

`Readonly`setWorkerChoiceStrategy

Sets the default worker choice strategy in this pool.

Type declaration

- (
      workerChoiceStrategy:
          | "FAIR_SHARE"
          | "INTERLEAVED_WEIGHTED_ROUND_ROBIN"
          | "LEAST_BUSY"
          | "LEAST_ELU"
          | "LEAST_USED"
          | "ROUND_ROBIN"
          | "WEIGHTED_ROUND_ROBIN",
      workerChoiceStrategyOptions?: WorkerChoiceStrategyOptions,
  ): void
- Parameters
  - workerChoiceStrategy:
        | "FAIR_SHARE"
        | "INTERLEAVED_WEIGHTED_ROUND_ROBIN"
        | "LEAST_BUSY"
        | "LEAST_ELU"
        | "LEAST_USED"
        | "ROUND_ROBIN"
        | "WEIGHTED_ROUND_ROBIN"
    The default worker choice strategy.
  - OptionalworkerChoiceStrategyOptions: WorkerChoiceStrategyOptions
    The worker choice strategy options.
  Returns void

`Readonly`setWorkerChoiceStrategyOptions

setWorkerChoiceStrategyOptions: (
workerChoiceStrategyOptions: WorkerChoiceStrategyOptions,
) => boolean

Sets the worker choice strategy options in this pool.

Type declaration

- (workerChoiceStrategyOptions: WorkerChoiceStrategyOptions): boolean
- Parameters
  - workerChoiceStrategyOptions: WorkerChoiceStrategyOptions
    The worker choice strategy options.
  Returns boolean
  true if the worker choice strategy options were set, false otherwise.

`Readonly`start

start: () => void

Starts the minimum number of workers in this pool.

`Readonly` `Internal`workerNodes

workerNodes: IWorkerNode<Worker, Data>[]

Pool worker nodes.

Interface IPool<Worker, Data, Response>

Type Parameters

Implemented by

Index

Properties

Properties

ReadonlyaddTaskFunction

Type declaration

Parameters

Returns Promise<boolean>

Throws

Throws

Readonlydestroy

Optional Readonlyemitter

ReadonlyenableTasksQueue

Type declaration

Parameters

Returns void

Readonlyexecute

Type declaration

Parameters

Returns Promise<Response>

ReadonlyhasTaskFunction

Type declaration

Parameters

Returns boolean

Readonlyinfo

ReadonlylistTaskFunctionsProperties

Type declaration

Returns TaskFunctionProperties[]

ReadonlymapExecute

Type declaration

Parameters

Returns Promise<Response[]>

ReadonlyremoveTaskFunction

Type declaration

Parameters

Returns Promise<boolean>

ReadonlysetDefaultTaskFunction

Type declaration

Parameters

Returns Promise<boolean>

ReadonlysetTasksQueueOptions

Type declaration

Parameters

Returns void

ReadonlysetWorkerChoiceStrategy

Type declaration

Parameters

Returns void

ReadonlysetWorkerChoiceStrategyOptions

Type declaration

Parameters

Returns boolean

Readonlystart

Readonly InternalworkerNodes

Settings

On This Page

`Readonly`addTaskFunction

`Readonly`destroy

`Optional` `Readonly`emitter

`Readonly`enableTasksQueue

`Readonly`execute

`Readonly`hasTaskFunction

`Readonly`info

`Readonly`listTaskFunctionsProperties

`Readonly`mapExecute

`Readonly`removeTaskFunction

`Readonly`setDefaultTaskFunction

`Readonly`setTasksQueueOptions

`Readonly`setWorkerChoiceStrategy

`Readonly`setWorkerChoiceStrategyOptions

`Readonly`start

`Readonly` `Internal`workerNodes