-import Constants from '../utils/Constants';
+// Partial Copyright Jerome Benoit. 2021. All Rights Reserved.
+
+import { WorkerMessageEvents, WorkerOptions, WorkerSetElement } from '../types/Worker';
+
import Utils from '../utils/Utils';
import { Worker } from 'worker_threads';
-import WorkerData from '../types/WorkerData';
-import { WorkerEvents } from '../types/WorkerEvents';
-import Wrk from './Wrk';
+import WorkerAbstract from './WorkerAbstract';
+import { WorkerUtils } from './WorkerUtils';
-export default class WorkerSet extends Wrk {
- public maxElementsPerWorker: number;
- private workers: Set<Worker>;
- private lastWorkerNumberOfElements: number;
+export default class WorkerSet<T> extends WorkerAbstract {
+ public readonly maxElementsPerWorker: number;
+ private readonly messageHandler: (message: unknown) => void | Promise<void>;
+ private workerSet: Set<WorkerSetElement>;
/**
* Create a new `WorkerSet`.
*
- * @param {string} workerScript
- * @param {number} maxElementsPerWorker
+ * @param workerScript
+ * @param maxElementsPerWorker
+ * @param workerStartDelay
+ * @param opts
*/
- constructor(workerScript: string, maxElementsPerWorker = 1) {
- super(workerScript);
- this.workers = new Set<Worker>();
+ constructor(workerScript: string, maxElementsPerWorker = 1, workerStartDelay?: number, opts?: WorkerOptions) {
+ super(workerScript, workerStartDelay);
this.maxElementsPerWorker = maxElementsPerWorker;
- this.lastWorkerNumberOfElements = 0;
+ this.messageHandler = opts?.messageHandler ?? (() => { /* This is intentional */ });
+ this.workerSet = new Set<WorkerSetElement>();
}
get size(): number {
- return this.workers.size;
+ return this.workerSet.size;
}
/**
*
- * @return {Promise<void>}
+ * @param elementData
+ * @returns
* @public
*/
- public async addElement(elementData: WorkerData): Promise<void> {
- if (!this.workers) {
- throw Error('Cannot add a WorkerSet element: workers set does not exist');
+ 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.lastWorkerNumberOfElements >= this.maxElementsPerWorker) {
- void this.startWorker();
- this.lastWorkerNumberOfElements = 0;
+ if (this.getLastWorkerSetElement().numberOfWorkerElements >= this.maxElementsPerWorker) {
+ this.startWorker();
// Start worker sequentially to optimize memory at startup
- void Utils.sleep(Constants.START_WORKER_DELAY);
+ await Utils.sleep(this.workerStartDelay);
}
- this.getLastWorker().postMessage({ id: WorkerEvents.START_WORKER_ELEMENT, workerData: elementData });
- this.lastWorkerNumberOfElements++;
+ this.getLastWorker().postMessage({ id: WorkerMessageEvents.START_WORKER_ELEMENT, data: elementData });
+ this.getLastWorkerSetElement().numberOfWorkerElements++;
}
/**
*
- * @return {Promise<void>}
+ * @returns
* @public
*/
public async start(): Promise<void> {
- await this.startWorker();
+ this.startWorker();
// Start worker sequentially to optimize memory at startup
- await Utils.sleep(Constants.START_WORKER_DELAY);
+ await Utils.sleep(this.workerStartDelay);
+ }
+
+ /**
+ *
+ * @returns
+ * @public
+ */
+ public async stop(): Promise<void> {
+ for (const workerSetElement of this.workerSet) {
+ await workerSetElement.worker.terminate();
+ }
+ this.workerSet.clear();
}
/**
*
- * @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 startWorker(): void {
+ const worker = new Worker(this.workerScript);
+ worker.on('message', (msg) => {
+ (async () => {
+ await this.messageHandler(msg);
+ })().catch(() => { /* 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 getLastWorkerSetElement(): WorkerSetElement {
+ let workerSetElement: WorkerSetElement;
+ for (workerSetElement of this.workerSet) { /* This is intentional */ }
+ return workerSetElement;
}
private getLastWorker(): Worker {
- let worker: Worker;
- // eslint-disable-next-line no-empty
- for (worker of this.workers) { }
- return worker;
+ return this.getLastWorkerSetElement().worker;
+ }
+
+ private getWorkerSetElementByWorker(worker: Worker): WorkerSetElement {
+ let workerSetElt: WorkerSetElement;
+ for (const workerSetElement of this.workerSet) {
+ if (workerSetElement.worker.threadId === worker.threadId) {
+ workerSetElt = workerSetElement;
+ break;
+ }
+ }
+ return workerSetElt;
}
}