refactor: cleanup default worker options handling
[e-mobility-charging-stations-simulator.git] / src / worker / WorkerSet.ts
index 681609585de1d388fe59135fb778fcf39fccc384..ce25e7e3a6e4ec3428072a05fc6e13d90e14c0fd 100644 (file)
@@ -1,44 +1,60 @@
 // Partial Copyright Jerome Benoit. 2021-2023. All Rights Reserved.
 
-import EventEmitterAsyncResource from 'node:events';
-import { Worker } from 'node:worker_threads';
+import { EventEmitter } from 'node:events';
+import { SHARE_ENV, Worker } from 'node:worker_threads';
+
+import type { ThreadPoolOptions } from 'poolifier';
 
 import { WorkerAbstract } from './WorkerAbstract';
 import { WorkerConstants } from './WorkerConstants';
 import {
-  type MessageHandler,
   type SetInfo,
   type WorkerData,
   WorkerMessageEvents,
   type WorkerOptions,
   type WorkerSetElement,
+  WorkerSetEvents,
 } from './WorkerTypes';
-import { defaultErrorHandler, defaultExitHandler, sleep } from './WorkerUtils';
+import { sleep } from './WorkerUtils';
+
+const DEFAULT_POOL_OPTIONS: ThreadPoolOptions = {
+  enableEvents: true,
+  restartWorkerOnError: true,
+};
 
 export class WorkerSet extends WorkerAbstract<WorkerData> {
-  public readonly emitter: EventEmitterAsyncResource;
+  public readonly emitter!: EventEmitter;
   private readonly workerSet: Set<WorkerSetElement>;
 
   /**
-   * Create a new `WorkerSet`.
+   * Creates a new `WorkerSet`.
    *
    * @param workerScript -
    * @param workerOptions -
    */
-  constructor(workerScript: string, workerOptions?: WorkerOptions) {
+  constructor(workerScript: string, workerOptions: WorkerOptions) {
     super(workerScript, workerOptions);
+    this.workerOptions.poolOptions = {
+      ...DEFAULT_POOL_OPTIONS,
+      ...this.workerOptions.poolOptions,
+    };
     this.workerSet = new Set<WorkerSetElement>();
-    this.emitter = new EventEmitterAsyncResource();
+    if (this.workerOptions.poolOptions?.enableEvents) {
+      this.emitter = new EventEmitter();
+    }
   }
 
   get info(): SetInfo {
     return {
+      version: WorkerConstants.version,
+      type: 'set',
+      worker: 'thread',
       size: this.size,
-      runningElements: [...this.workerSet].reduce(
+      elementsExecuting: [...this.workerSet].reduce(
         (accumulator, workerSetElement) => accumulator + workerSetElement.numberOfWorkerElements,
-        0
+        0,
       ),
-      elementsPerWorker: this.maxElementsPerWorker,
+      elementsPerWorker: this.maxElementsPerWorker!,
     };
   }
 
@@ -54,13 +70,19 @@ export class WorkerSet extends WorkerAbstract<WorkerData> {
   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));
+    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();
   }
@@ -77,38 +99,57 @@ export class WorkerSet extends WorkerAbstract<WorkerData> {
     });
     ++workerSetElement.numberOfWorkerElements;
     // Add element sequentially to optimize memory at startup
-    if (this.workerOptions.elementStartDelay > 0) {
-      await sleep(this.workerOptions.elementStartDelay);
+    if (this.workerOptions.elementStartDelay! > 0) {
+      await sleep(this.workerOptions.elementStartDelay!);
     }
   }
 
   /**
-   * Add a new `WorkerSetElement`.
+   * Adds a new `WorkerSetElement`.
    */
   private addWorkerSetElement(): WorkerSetElement {
-    const worker = new Worker(this.workerScript);
+    const worker = new Worker(this.workerScript, {
+      env: SHARE_ENV,
+      ...this.workerOptions.poolOptions?.workerOptions,
+    });
     worker.on(
       'message',
-      (this.workerOptions?.messageHandler ?? WorkerConstants.EMPTY_FUNCTION).bind(
-        this
-      ) as MessageHandler<Worker>
+      this.workerOptions.poolOptions?.messageHandler ?? WorkerConstants.EMPTY_FUNCTION,
+    );
+    worker.on(
+      'error',
+      this.workerOptions.poolOptions?.errorHandler ?? WorkerConstants.EMPTY_FUNCTION,
     );
-    worker.on('error', defaultErrorHandler.bind(this) as (err: Error) => void);
     worker.on('error', (error) => {
-      this.emitter.emit('error', error);
-      this.addWorkerSetElement();
+      this.emitter?.emit(WorkerSetEvents.error, error);
+      if (this.workerOptions.poolOptions?.restartWorkerOnError) {
+        this.addWorkerSetElement();
+      }
     });
-    worker.on('exit', defaultExitHandler.bind(this) as (exitCode: number) => void);
-    worker.on('exit', () => this.workerSet.delete(this.getWorkerSetElementByWorker(worker)));
+    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;
   }
 
+  private removeWorkerSetElement(workerSetElement: WorkerSetElement): void {
+    this.workerSet.delete(workerSetElement);
+  }
+
   private async getWorkerSetElement(): Promise<WorkerSetElement> {
-    let chosenWorkerSetElement: WorkerSetElement;
+    let chosenWorkerSetElement: WorkerSetElement | undefined;
     for (const workerSetElement of this.workerSet) {
-      if (workerSetElement.numberOfWorkerElements < this.workerOptions.elementsPerWorker) {
+      if (workerSetElement.numberOfWorkerElements < this.workerOptions.elementsPerWorker!) {
         chosenWorkerSetElement = workerSetElement;
         break;
       }
@@ -116,13 +157,14 @@ export class WorkerSet extends WorkerAbstract<WorkerData> {
     if (!chosenWorkerSetElement) {
       chosenWorkerSetElement = this.addWorkerSetElement();
       // Add worker set element sequentially to optimize memory at startup
-      this.workerOptions.workerStartDelay > 0 && (await sleep(this.workerOptions.workerStartDelay));
+      this.workerOptions.workerStartDelay! > 0 &&
+        (await sleep(this.workerOptions.workerStartDelay!));
     }
     return chosenWorkerSetElement;
   }
 
   private getWorkerSetElementByWorker(worker: Worker): WorkerSetElement | undefined {
-    let workerSetElt: WorkerSetElement;
+    let workerSetElt: WorkerSetElement | undefined;
     for (const workerSetElement of this.workerSet) {
       if (workerSetElement.worker.threadId === worker.threadId) {
         workerSetElt = workerSetElement;