-import { WorkerEvents, WorkerSetElement } from '../types/Worker';
+// Partial Copyright Jerome Benoit. 2021-2023. All Rights Reserved.
-import Constants from '../utils/Constants';
-import Utils from '../utils/Utils';
-import { Worker } from 'worker_threads';
-import Wrk from './Wrk';
+import { EventEmitterAsyncResource } from 'node:events';
+import { SHARE_ENV, Worker } from 'node:worker_threads';
-export default class WorkerSet<T> extends Wrk {
- public maxElementsPerWorker: number;
- private workers: Set<WorkerSetElement>;
+import { WorkerAbstract } from './WorkerAbstract';
+import { EMPTY_FUNCTION, workerSetVersion } from './WorkerConstants';
+import {
+ type SetInfo,
+ type WorkerData,
+ type WorkerMessage,
+ WorkerMessageEvents,
+ type WorkerOptions,
+ type WorkerSetElement,
+ WorkerSetEvents,
+} from './WorkerTypes';
+import { randomizeDelay, sleep } from './WorkerUtils';
+
+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 workerScript -
+ * @param workerOptions -
*/
- constructor(workerScript: string, maxElementsPerWorker = 1) {
- super(workerScript);
- this.workers = new Set<WorkerSetElement>();
- this.maxElementsPerWorker = maxElementsPerWorker;
+ constructor(workerScript: string, workerOptions: WorkerOptions) {
+ super(workerScript, workerOptions);
+ if (
+ this.workerOptions.elementsPerWorker === null ||
+ this.workerOptions.elementsPerWorker === undefined
+ ) {
+ 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) {
+ this.emitter = new EventEmitterAsyncResource({ name: 'workerset' });
+ }
+ this.started = false;
+ this.workerStartup = false;
+ }
+
+ get info(): SetInfo {
+ return {
+ version: workerSetVersion,
+ 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
- */
- public async addElement(elementData: T): Promise<void> {
- if (!this.workers) {
- throw 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(Constants.START_WORKER_DELAY);
- }
- this.getLastWorker().postMessage({ id: WorkerEvents.START_WORKER_ELEMENT, workerData: elementData });
- this.getLastWorkerSetElement().numberOfWorkerElements++;
+ get maxElementsPerWorker(): number | undefined {
+ return this.workerOptions.elementsPerWorker;
}
- /**
- *
- * @return {Promise<void>}
- * @public
- */
+ /** @inheritDoc */
public async start(): Promise<void> {
- this.startWorker();
- // Start worker sequentially to optimize memory at startup
- await Utils.sleep(Constants.START_WORKER_DELAY);
+ this.addWorkerSetElement();
+ // Add worker set element sequentially to optimize memory at startup
+ this.workerOptions.workerStartDelay! > 0 &&
+ (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) {
+ 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');
+ }
+ if (this.workerSet == null) {
+ throw new Error("Cannot add a WorkerSet element: 'workerSet' property does not exist");
+ }
+ const workerSetElement = await this.getWorkerSetElement();
+ workerSetElement.worker.postMessage({
+ event: WorkerMessageEvents.startWorkerElement,
+ data: elementData,
+ });
+ ++workerSetElement.numberOfWorkerElements;
+ // Add element sequentially to optimize memory at startup
+ if (this.workerOptions.elementStartDelay! > 0) {
+ await sleep(randomizeDelay(this.workerOptions.elementStartDelay!));
+ }
}
/**
- *
- * @return {Promise}
- * @private
+ * Adds a new `WorkerSetElement`.
*/
- private startWorker(): void {
- const worker = new Worker(this.workerScript);
- worker.on('message', () => { });
- worker.on('error', () => { });
- worker.on('exit', (code) => {
- if (code !== 0) {
- console.error(`Worker stopped with exit code ${code}`);
+ 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);
}
- // FIXME: remove matching worker set element
});
- this.workers.add({ worker, numberOfWorkerElements: 0 });
+ worker.on('error', this.workerOptions.poolOptions?.errorHandler ?? EMPTY_FUNCTION);
+ worker.on('error', (error) => {
+ this.emitter?.emit(WorkerSetEvents.error, error);
+ if (
+ this.workerOptions.poolOptions?.restartWorkerOnError &&
+ 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.workers) { }
- return workerSetElement;
+ private removeWorkerSetElement(workerSetElement: WorkerSetElement): void {
+ 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) {
+ 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(randomizeDelay(this.workerOptions.workerStartDelay!)));
+ }
+ return chosenWorkerSetElement;
}
- private getWorkerSetElementByWorker(worker: Worker): WorkerSetElement {
- let workerSetElt: WorkerSetElement;
- this.workers.forEach((workerSetElement) => {
- if (JSON.stringify(workerSetElement.worker) === JSON.stringify(worker)) {
+ 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;
}
- });
+ }
return workerSetElt;
}
}