-// Partial Copyright Jerome Benoit. 2021. All Rights Reserved.
+// Partial Copyright Jerome Benoit. 2021-2024. All Rights Reserved.
-import { WorkerEvents, WorkerSetElement } from '../types/Worker';
+import { EventEmitterAsyncResource } from 'node:events'
+import { SHARE_ENV, Worker } from 'node:worker_threads'
-import Utils from '../utils/Utils';
-import { Worker } from 'worker_threads';
-import WorkerAbstract from './WorkerAbstract';
-import { WorkerUtils } from './WorkerUtils';
+import { WorkerAbstract } from './WorkerAbstract.js'
+import { EMPTY_FUNCTION, workerSetVersion } from './WorkerConstants.js'
+import {
+ type SetInfo,
+ type WorkerData,
+ type WorkerMessage,
+ WorkerMessageEvents,
+ type WorkerOptions,
+ type WorkerSetElement,
+ WorkerSetEvents
+} from './WorkerTypes.js'
+import { randomizeDelay, sleep } from './WorkerUtils.js'
-export default class WorkerSet<T> extends WorkerAbstract {
- public maxElementsPerWorker: number;
- private workerSet: Set<WorkerSetElement>;
+export class WorkerSet extends WorkerAbstract<WorkerData> {
+ public readonly emitter: EventEmitterAsyncResource | undefined
+ private readonly workerSet: Set<WorkerSetElement>
+ private started: boolean
+ private workerStartup: boolean
/**
- * Create a new `WorkerSet`.
+ * Creates a new `WorkerSet`.
*
- * @param {string} workerScript
- * @param {number} maxElementsPerWorker
- * @param {number} workerStartDelay
+ * @param workerScript -
+ * @param workerOptions -
*/
- constructor(workerScript: string, maxElementsPerWorker = 1, workerStartDelay?: number) {
- super(workerScript, workerStartDelay);
- this.workerSet = new Set<WorkerSetElement>();
- this.maxElementsPerWorker = maxElementsPerWorker;
+ constructor (workerScript: string, workerOptions: WorkerOptions) {
+ super(workerScript, workerOptions)
+ if (this.workerOptions.elementsPerWorker == null) {
+ throw new TypeError('Elements per worker is not defined')
+ }
+ if (!Number.isSafeInteger(this.workerOptions.elementsPerWorker)) {
+ throw new TypeError('Elements per worker must be an integer')
+ }
+ if (this.workerOptions.elementsPerWorker <= 0) {
+ throw new RangeError('Elements per worker must be greater than zero')
+ }
+ this.workerSet = new Set<WorkerSetElement>()
+ if (this.workerOptions.poolOptions?.enableEvents === true) {
+ this.emitter = new EventEmitterAsyncResource({ name: 'workerset' })
+ }
+ this.started = false
+ this.workerStartup = false
}
- get size(): number {
- return this.workerSet.size;
+ get info (): SetInfo {
+ return {
+ version: workerSetVersion,
+ type: 'set',
+ worker: 'thread',
+ size: this.size,
+ elementsExecuting: [...this.workerSet].reduce(
+ (accumulator, workerSetElement) => accumulator + workerSetElement.numberOfWorkerElements,
+ 0
+ ),
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ elementsPerWorker: this.maxElementsPerWorker!
+ }
}
- /**
- *
- * @param {T} elementData
- * @returns {Promise<void>}
- * @public
- */
- public async addElement(elementData: T): Promise<void> {
- if (!this.workerSet) {
- throw new Error('Cannot add a WorkerSet element: workers\' set does not exist');
- }
- if (this.getLastWorkerSetElement().numberOfWorkerElements >= this.maxElementsPerWorker) {
- this.startWorker();
- // Start worker sequentially to optimize memory at startup
- await Utils.sleep(this.workerStartDelay);
- }
- this.getLastWorker().postMessage({ id: WorkerEvents.START_WORKER_ELEMENT, workerData: elementData });
- this.getLastWorkerSetElement().numberOfWorkerElements++;
+ get size (): number {
+ return this.workerSet.size
}
- /**
- *
- * @returns {Promise<void>}
- * @public
- */
- public async start(): Promise<void> {
- this.startWorker();
- // Start worker sequentially to optimize memory at startup
- await Utils.sleep(this.workerStartDelay);
+ get maxElementsPerWorker (): number | undefined {
+ return this.workerOptions.elementsPerWorker
}
- /**
- *
- * @returns {Promise<void>}
- * @public
- */
- public async stop(): Promise<void> {
+ /** @inheritDoc */
+ public async start (): Promise<void> {
+ this.addWorkerSetElement()
+ // Add worker set element sequentially to optimize memory at startup
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ this.workerOptions.workerStartDelay! > 0 &&
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ (await sleep(randomizeDelay(this.workerOptions.workerStartDelay!)))
+ this.emitter?.emit(WorkerSetEvents.started, this.info)
+ this.started = true
+ }
+
+ /** @inheritDoc */
+ public async stop (): Promise<void> {
for (const workerSetElement of this.workerSet) {
- await workerSetElement.worker.terminate();
+ const worker = workerSetElement.worker
+ const waitWorkerExit = new Promise<void>(resolve => {
+ worker.once('exit', () => {
+ resolve()
+ })
+ })
+ await worker.terminate()
+ await waitWorkerExit
+ this.emitter?.emit(WorkerSetEvents.stopped, this.info)
+ this.emitter?.emitDestroy()
+ this.emitter?.removeAllListeners()
+ this.started = false
+ }
+ }
+
+ /** @inheritDoc */
+ public async addElement (elementData: WorkerData): Promise<void> {
+ if (!this.started) {
+ throw new Error('Cannot add a WorkerSet element: not started')
+ }
+ const workerSetElement = await this.getWorkerSetElement()
+ workerSetElement.worker.postMessage({
+ event: WorkerMessageEvents.startWorkerElement,
+ data: elementData
+ })
+ ++workerSetElement.numberOfWorkerElements
+ // Add element sequentially to optimize memory at startup
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ if (this.workerOptions.elementStartDelay! > 0) {
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ await sleep(randomizeDelay(this.workerOptions.elementStartDelay!))
}
- this.workerSet.clear();
}
/**
- *
- * @private
+ * Adds a new `WorkerSetElement`.
*/
- private startWorker(): void {
- const worker = new Worker(this.workerScript);
- worker.on('message', () => { /* This is intentional */ });
- worker.on('error', () => { /* This is intentional */ });
- worker.on('exit', (code) => {
- WorkerUtils.defaultExitHandler(code);
- this.workerSet.delete(this.getWorkerSetElementByWorker(worker));
- });
- this.workerSet.add({ worker, numberOfWorkerElements: 0 });
+ private addWorkerSetElement (): WorkerSetElement {
+ this.workerStartup = true
+ const worker = new Worker(this.workerScript, {
+ env: SHARE_ENV,
+ ...this.workerOptions.poolOptions?.workerOptions
+ })
+ worker.on('message', this.workerOptions.poolOptions?.messageHandler ?? EMPTY_FUNCTION)
+ worker.on('message', (message: WorkerMessage<WorkerData>) => {
+ if (message.event === WorkerMessageEvents.startedWorkerElement) {
+ this.emitter?.emit(WorkerSetEvents.elementStarted, this.info)
+ } else if (message.event === WorkerMessageEvents.startWorkerElementError) {
+ this.emitter?.emit(WorkerSetEvents.elementError, message.data)
+ }
+ })
+ worker.on('error', this.workerOptions.poolOptions?.errorHandler ?? EMPTY_FUNCTION)
+ worker.on('error', error => {
+ this.emitter?.emit(WorkerSetEvents.error, error)
+ if (
+ this.workerOptions.poolOptions?.restartWorkerOnError === true &&
+ this.started &&
+ !this.workerStartup
+ ) {
+ this.addWorkerSetElement()
+ }
+ })
+ worker.on('online', this.workerOptions.poolOptions?.onlineHandler ?? EMPTY_FUNCTION)
+ worker.on('exit', this.workerOptions.poolOptions?.exitHandler ?? EMPTY_FUNCTION)
+ worker.once('exit', () => {
+ this.removeWorkerSetElement(this.getWorkerSetElementByWorker(worker))
+ })
+ const workerSetElement: WorkerSetElement = { worker, numberOfWorkerElements: 0 }
+ this.workerSet.add(workerSetElement)
+ this.workerStartup = false
+ return workerSetElement
}
- private getLastWorkerSetElement(): WorkerSetElement {
- let workerSetElement: WorkerSetElement;
- // eslint-disable-next-line no-empty
- for (workerSetElement of this.workerSet) { /* This is intentional */ }
- return workerSetElement;
+ private removeWorkerSetElement (workerSetElement: WorkerSetElement | undefined): void {
+ if (workerSetElement == null) {
+ return
+ }
+ this.workerSet.delete(workerSetElement)
}
- private getLastWorker(): Worker {
- return this.getLastWorkerSetElement().worker;
+ private async getWorkerSetElement (): Promise<WorkerSetElement> {
+ let chosenWorkerSetElement: WorkerSetElement | undefined
+ for (const workerSetElement of this.workerSet) {
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ if (workerSetElement.numberOfWorkerElements < this.workerOptions.elementsPerWorker!) {
+ chosenWorkerSetElement = workerSetElement
+ break
+ }
+ }
+ if (chosenWorkerSetElement == null) {
+ chosenWorkerSetElement = this.addWorkerSetElement()
+ // Add worker set element sequentially to optimize memory at startup
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ this.workerOptions.workerStartDelay! > 0 &&
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ (await sleep(randomizeDelay(this.workerOptions.workerStartDelay!)))
+ }
+ return chosenWorkerSetElement
}
- private getWorkerSetElementByWorker(worker: Worker): WorkerSetElement {
- let workerSetElt: WorkerSetElement;
+ private getWorkerSetElementByWorker (worker: Worker): WorkerSetElement | undefined {
+ let workerSetElt: WorkerSetElement | undefined
for (const workerSetElement of this.workerSet) {
if (workerSetElement.worker.threadId === worker.threadId) {
- workerSetElt = workerSetElement;
- break;
+ workerSetElt = workerSetElement
+ break
}
}
- return workerSetElt;
+ return workerSetElt
}
}