fix: fix possible null exception with worker_threads pools

[poolifier.git] / src / pools / pool.ts

diff --git a/src/pools/pool.ts b/src/pools/pool.ts
index 212253ffbc5be7faff8760dc3847f9cdc486bb89..b1b504d59b22bba2aca61becc898fa87167c5c6c 100644 (file)
--- a/src/pools/pool.ts
+++ b/src/pools/pool.ts
@@ -1,5 +1,5 @@
-import { EventEmitter } from 'node:events'
-import { type TransferListItem } from 'node:worker_threads'
+import type { TransferListItem } from 'node:worker_threads'
+import type { EventEmitterAsyncResource } from 'node:events'
 import type { TaskFunction } from '../worker/task-functions'
 import type {
   ErrorHandler,
@@ -34,11 +34,6 @@ export const PoolTypes = Object.freeze({
  */
 export type PoolType = keyof typeof PoolTypes
 
-/**
- * Pool events emitter.
- */
-export class PoolEmitter extends EventEmitter {}
-
 /**
  * Enumeration of pool events.
  */
@@ -115,13 +110,13 @@ export interface TasksQueueOptions {
    */
   readonly concurrency?: number
   /**
-   * Whether to enable task stealing.
+   * Whether to enable task stealing on idle.
    *
    * @defaultValue true
    */
   readonly taskStealing?: boolean
   /**
-   * Whether to enable tasks stealing on back pressure.
+   * Whether to enable tasks stealing under back pressure.
    *
    * @defaultValue true
    */
@@ -179,7 +174,7 @@ export interface PoolOptions<Worker extends IWorker> {
    */
   restartWorkerOnError?: boolean
   /**
-   * Pool events emission.
+   * Pool events integrated with async resource emission.
    *
    * @defaultValue true
    */
@@ -227,7 +222,8 @@ export interface IPool<
    */
   readonly hasWorkerNodeBackPressure: (workerNodeKey: number) => boolean
   /**
-   * Emitter on which events can be listened to.
+   * Event emitter integrated with async resource on which events can be listened to.
+   * The async tracking tooling identifier is `poolifier:<PoolType>-<WorkerType>-pool`.
    *
    * Events that can currently be listened to:
    *
@@ -239,13 +235,13 @@ export interface IPool<
    * - `'taskError'`: Emitted when an error occurs while executing a task.
    * - `'backPressure'`: Emitted when all worker nodes have back pressure (i.e. their tasks queue is full: queue size \>= maximum queue size).
    */
-  readonly emitter?: PoolEmitter
+  readonly emitter?: EventEmitterAsyncResource
   /**
    * Executes the specified function in the worker constructor with the task data input parameter.
    *
    * @param data - The optional task input data for the specified task function. This can only be structured-cloneable data.
    * @param name - The optional name of the task function to execute. If not specified, the default task function will be executed.
-   * @param transferList - An optional array of transferable objects to transfer ownership of. Ownership of the transferred objects is given to the pool's worker_threads worker and they should not be used in the main thread afterwards.
+   * @param transferList - An 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 that will be fulfilled when the task is completed.
    */
   readonly execute: (
@@ -273,12 +269,14 @@ export interface IPool<
    * If a task function with the same name already exists, it will be overwritten.
    *
    * @param name - The name of the task function.
-   * @param taskFunction - The task function.
+   * @param fn - The task function.
    * @returns `true` if the task function was added, `false` otherwise.
+   * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `name` parameter is not a string or an empty string.
+   * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `fn` parameter is not a function.
    */
   readonly addTaskFunction: (
     name: string,
-    taskFunction: TaskFunction<Data, Response>
+    fn: TaskFunction<Data, Response>
   ) => Promise<boolean>
   /**
    * Removes a task function from this pool.