WorkerSet: remove ugly hack to deal with async worker message handler

[e-mobility-charging-stations-simulator.git] / src / worker / WorkerSet.ts

diff --git a/src/worker/WorkerSet.ts b/src/worker/WorkerSet.ts
index 0e6855f1887cf6f1d3563bf45b3a07b7e6d7f8b1..f41752fc7a2b088fda4b8c68b4b74bec347b1bf9 100644 (file)
--- a/src/worker/WorkerSet.ts
+++ b/src/worker/WorkerSet.ts
@@ -1,63 +1,79 @@
-import { WorkerEvents, WorkerSetElement } from '../types/Worker';
+// Partial Copyright Jerome Benoit. 2021. All Rights Reserved.
 
-import Utils from '../utils/Utils';
 import { Worker } from 'worker_threads';
+
+import { WorkerData, WorkerMessageEvents, WorkerOptions, WorkerSetElement } from '../types/Worker';
+import Utils from '../utils/Utils';
 import WorkerAbstract from './WorkerAbstract';
+import { WorkerUtils } from './WorkerUtils';
 
-export default class WorkerSet<T> extends WorkerAbstract {
-  public maxElementsPerWorker: number;
-  private workerSet: Set<WorkerSetElement>;
+export default class WorkerSet extends WorkerAbstract<WorkerData> {
+  private readonly workerSet: Set<WorkerSetElement>;
+  private readonly messageHandler: (message: unknown) => void;
 
   /**
    * Create 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);
+  constructor(workerScript: string, workerOptions?: WorkerOptions) {
+    super(workerScript, workerOptions);
     this.workerSet = new Set<WorkerSetElement>();
-    this.maxElementsPerWorker = maxElementsPerWorker;
+    this.messageHandler =
+      workerOptions?.messageHandler ??
+      (() => {
+        /* This is intentional */
+      });
   }
 
   get size(): number {
     return this.workerSet.size;
   }
 
+  get maxElementsPerWorker(): number | null {
+    return this.workerOptions.elementsPerWorker;
+  }
+
   /**
    *
    * @param elementData
-   * @returns {Promise<void>}
+   * @returns
    * @public
    */
-  public async addElement(elementData: T): Promise<void> {
+  public async addElement(elementData: WorkerData): Promise<void> {
     if (!this.workerSet) {
-      throw Error('Cannot add a WorkerSet element: workers\' set does not exist');
+      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);
+    if (
+      this.workerSet.size === 0 ||
+      this.getLastWorkerSetElement().numberOfWorkerElements >= this.workerOptions.elementsPerWorker
+    ) {
+      await this.startWorker();
     }
-    this.getLastWorker().postMessage({ id: WorkerEvents.START_WORKER_ELEMENT, workerData: elementData });
+    this.getLastWorker().postMessage({
+      id: WorkerMessageEvents.START_WORKER_ELEMENT,
+      data: elementData,
+    });
     this.getLastWorkerSetElement().numberOfWorkerElements++;
+    // Start element sequentially to optimize memory at startup
+    if (this.workerOptions.elementStartDelay > 0) {
+      await Utils.sleep(this.workerOptions.elementStartDelay);
+    }
   }
 
   /**
    *
-   * @returns {Promise<void>}
+   * @returns
    * @public
    */
   public async start(): Promise<void> {
-    this.startWorker();
-    // Start worker sequentially to optimize memory at startup
-    await Utils.sleep(this.workerStartDelay);
+    await this.startWorker();
   }
 
   /**
    *
-   * @returns {Promise<void>}
+   * @returns
    * @public
    */
   public async stop(): Promise<void> {
@@ -71,23 +87,25 @@ export default class WorkerSet<T> extends WorkerAbstract {
    *
    * @private
    */
-  private startWorker(): void {
+  private async startWorker(): Promise<void> {
     const worker = new Worker(this.workerScript);
-    worker.on('message', () => { });
-    worker.on('error', () => { });
+    worker.on('message', this.messageHandler);
+    worker.on('error', WorkerUtils.defaultErrorHandler);
     worker.on('exit', (code) => {
-      if (code !== 0) {
-        console.error(`Worker stopped with exit code ${code}`);
-      }
+      WorkerUtils.defaultExitHandler(code);
       this.workerSet.delete(this.getWorkerSetElementByWorker(worker));
     });
     this.workerSet.add({ worker, numberOfWorkerElements: 0 });
+    // Start worker sequentially to optimize memory at startup
+    this.workerOptions.workerStartDelay > 0 &&
+      (await Utils.sleep(this.workerOptions.workerStartDelay));
   }
 
   private getLastWorkerSetElement(): WorkerSetElement {
     let workerSetElement: WorkerSetElement;
-    // eslint-disable-next-line no-empty
-    for (workerSetElement of this.workerSet) { }
+    for (workerSetElement of this.workerSet) {
+      /* This is intentional */
+    }
     return workerSetElement;
   }
 
@@ -97,11 +115,12 @@ export default class WorkerSet<T> extends WorkerAbstract {
 
   private getWorkerSetElementByWorker(worker: Worker): WorkerSetElement {
     let workerSetElt: WorkerSetElement;
-    this.workerSet.forEach((workerSetElement) => {
-      if (JSON.stringify(workerSetElement.worker) === JSON.stringify(worker)) {
+    for (const workerSetElement of this.workerSet) {
+      if (workerSetElement.worker.threadId === worker.threadId) {
         workerSetElt = workerSetElement;
+        break;
       }
-    });
+    }
     return workerSetElt;
   }
 }