-import Constants from '../utils/Constants';
-import Utils from '../utils/Utils';
-import { Worker } from 'worker_threads';
-import WorkerData from '../types/WorkerData';
-import { WorkerEvents } from '../types/WorkerEvents';
-import Wrk from './Wrk';
+// Partial Copyright Jerome Benoit. 2021-2023. All Rights Reserved.
-export default class WorkerSet extends Wrk {
- public maxElementsPerWorker: number;
- private workers: Set<Worker>;
- private lastWorkerNumberOfElements: number;
+import { EventEmitter } from 'node:events';
+import { SHARE_ENV, Worker } from 'node:worker_threads';
+
+import { WorkerAbstract } from './WorkerAbstract';
+import { WorkerConstants } from './WorkerConstants';
+import {
+ type SetInfo,
+ type WorkerData,
+ WorkerMessageEvents,
+ type WorkerOptions,
+ type WorkerSetElement,
+ WorkerSetEvents,
+} from './WorkerTypes';
+import { sleep } from './WorkerUtils';
+
+export class WorkerSet extends WorkerAbstract<WorkerData> {
+ public readonly emitter: EventEmitter;
+ private readonly workerSet: Set<WorkerSetElement>;
/**
- * Create a new `WorkerSet`.
+ * Creates a new `WorkerSet`.
*
- * @param {string} workerScript
- * @param {number} maxElementsPerWorker
+ * @param workerScript -
+ * @param workerOptions -
*/
- constructor(workerScript: string, maxElementsPerWorker = 1) {
- super(workerScript);
- this.workers = new Set<Worker>();
- this.maxElementsPerWorker = maxElementsPerWorker;
- this.lastWorkerNumberOfElements = 0;
+ constructor(workerScript: string, workerOptions?: WorkerOptions) {
+ super(workerScript, workerOptions);
+ this.workerOptions.poolOptions = {
+ ...{
+ enableEvents: true,
+ restartWorkerOnError: true,
+ },
+ ...this.workerOptions.poolOptions,
+ };
+ this.workerSet = new Set<WorkerSetElement>();
+ if (this.workerOptions?.poolOptions?.enableEvents) {
+ this.emitter = new EventEmitter();
+ }
+ }
+
+ get info(): SetInfo {
+ return {
+ version: WorkerConstants.version,
+ type: 'set',
+ worker: 'thread',
+ size: this.size,
+ elementsExecuting: [...this.workerSet].reduce(
+ (accumulator, workerSetElement) => accumulator + workerSetElement.numberOfWorkerElements,
+ 0,
+ ),
+ elementsPerWorker: this.maxElementsPerWorker,
+ };
}
get size(): number {
- return this.workers.size;
+ return this.workerSet.size;
}
- /**
- *
- * @return {Promise<void>}
- * @public
- */
+ get maxElementsPerWorker(): number | undefined {
+ return this.workerOptions.elementsPerWorker;
+ }
+
+ /** @inheritDoc */
+ public async start(): Promise<void> {
+ this.addWorkerSetElement();
+ // Add worker set element sequentially to optimize memory at startup
+ this.workerOptions.workerStartDelay > 0 && (await sleep(this.workerOptions.workerStartDelay));
+ }
+
+ /** @inheritDoc */
+ public async stop(): Promise<void> {
+ for (const workerSetElement of this.workerSet) {
+ const workerExitPromise = new Promise<void>((resolve) => {
+ workerSetElement.worker.on('exit', () => {
+ resolve();
+ });
+ });
+ await workerSetElement.worker.terminate();
+ await workerExitPromise;
+ }
+ this.workerSet.clear();
+ }
+
+ /** @inheritDoc */
public async addElement(elementData: WorkerData): Promise<void> {
- if (!this.workers) {
- throw Error('Cannot add a WorkerSet element: workers set does not exist');
+ if (!this.workerSet) {
+ throw new Error("Cannot add a WorkerSet element: workers' set does not exist");
}
- if (this.lastWorkerNumberOfElements >= this.maxElementsPerWorker) {
- void this.startWorker();
- this.lastWorkerNumberOfElements = 0;
- // Start worker sequentially to optimize memory at startup
- void Utils.sleep(Constants.START_WORKER_DELAY);
+ const workerSetElement = await this.getWorkerSetElement();
+ workerSetElement.worker.postMessage({
+ id: WorkerMessageEvents.startWorkerElement,
+ data: elementData,
+ });
+ ++workerSetElement.numberOfWorkerElements;
+ // Add element sequentially to optimize memory at startup
+ if (this.workerOptions.elementStartDelay > 0) {
+ await sleep(this.workerOptions.elementStartDelay);
}
- this.getLastWorker().postMessage({ id: WorkerEvents.START_WORKER_ELEMENT, workerData: elementData });
- this.lastWorkerNumberOfElements++;
}
/**
- *
- * @return {Promise<void>}
- * @public
+ * Adds a new `WorkerSetElement`.
*/
- public async start(): Promise<void> {
- await this.startWorker();
- // Start worker sequentially to optimize memory at startup
- await Utils.sleep(Constants.START_WORKER_DELAY);
+ private addWorkerSetElement(): WorkerSetElement {
+ const worker = new Worker(this.workerScript, {
+ env: SHARE_ENV,
+ ...this.workerOptions.poolOptions.workerOptions,
+ });
+ worker.on(
+ 'message',
+ this.workerOptions?.poolOptions?.messageHandler ?? WorkerConstants.EMPTY_FUNCTION,
+ );
+ worker.on(
+ 'error',
+ this.workerOptions?.poolOptions?.errorHandler ?? WorkerConstants.EMPTY_FUNCTION,
+ );
+ worker.on('error', (error) => {
+ this.emitter?.emit(WorkerSetEvents.error, error);
+ if (this.workerOptions?.poolOptions?.restartWorkerOnError) {
+ this.addWorkerSetElement();
+ }
+ });
+ worker.on(
+ 'online',
+ this.workerOptions?.poolOptions?.onlineHandler ?? WorkerConstants.EMPTY_FUNCTION,
+ );
+ worker.on(
+ 'exit',
+ this.workerOptions?.poolOptions?.exitHandler ?? WorkerConstants.EMPTY_FUNCTION,
+ );
+ worker.once('exit', () =>
+ this.removeWorkerSetElement(this.getWorkerSetElementByWorker(worker)),
+ );
+ const workerSetElement: WorkerSetElement = { worker, numberOfWorkerElements: 0 };
+ this.workerSet.add(workerSetElement);
+ return workerSetElement;
}
- /**
- *
- * @return {Promise}
- * @private
- */
- private async startWorker() {
- return new Promise((resolve, reject) => {
- const worker = new Worker(this.workerScript);
- worker.on('message', resolve);
- worker.on('error', reject);
- worker.on('exit', (code) => {
- if (code !== 0) {
- reject(new Error(`Worker stopped with exit code ${code}`));
- }
- });
- this.workers.add(worker);
- });
+ private removeWorkerSetElement(workerSetElement: WorkerSetElement): void {
+ this.workerSet.delete(workerSetElement);
+ }
+
+ private async getWorkerSetElement(): Promise<WorkerSetElement> {
+ let chosenWorkerSetElement: WorkerSetElement;
+ for (const workerSetElement of this.workerSet) {
+ if (workerSetElement.numberOfWorkerElements < this.workerOptions.elementsPerWorker) {
+ chosenWorkerSetElement = workerSetElement;
+ break;
+ }
+ }
+ if (!chosenWorkerSetElement) {
+ chosenWorkerSetElement = this.addWorkerSetElement();
+ // Add worker set element sequentially to optimize memory at startup
+ this.workerOptions.workerStartDelay > 0 && (await sleep(this.workerOptions.workerStartDelay));
+ }
+ return chosenWorkerSetElement;
}
- private getLastWorker(): Worker {
- let worker: Worker;
- // eslint-disable-next-line no-empty
- for (worker of this.workers) { }
- return worker;
+ private getWorkerSetElementByWorker(worker: Worker): WorkerSetElement | undefined {
+ let workerSetElt: WorkerSetElement;
+ for (const workerSetElement of this.workerSet) {
+ if (workerSetElement.worker.threadId === worker.threadId) {
+ workerSetElt = workerSetElement;
+ break;
+ }
+ }
+ return workerSetElt;
}
}