build: cleanup eslint configuration
[e-mobility-charging-stations-simulator.git] / src / worker / WorkerSet.ts
index 12f29294ea54b98ad82b1cca9013662725f3c223..17b5b6dde201c85f4c0af0cbaf3574d33968fb03 100644 (file)
@@ -1,10 +1,10 @@
 // Partial Copyright Jerome Benoit. 2021-2023. All Rights Reserved.
 
-import { EventEmitter } from 'node:events';
+import { EventEmitterAsyncResource } from 'node:events';
 import { SHARE_ENV, Worker } from 'node:worker_threads';
 
 import { WorkerAbstract } from './WorkerAbstract';
-import { DEFAULT_POOL_OPTIONS, EMPTY_FUNCTION, workerSetVersion } from './WorkerConstants';
+import { EMPTY_FUNCTION, workerSetVersion } from './WorkerConstants';
 import {
   type SetInfo,
   type WorkerData,
@@ -14,11 +14,12 @@ import {
   type WorkerSetElement,
   WorkerSetEvents,
 } from './WorkerTypes';
-import { sleep } from './WorkerUtils';
+import { randomizeDelay, sleep } from './WorkerUtils';
 
 export class WorkerSet extends WorkerAbstract<WorkerData> {
-  public readonly emitter!: EventEmitter;
+  public readonly emitter: EventEmitterAsyncResource | undefined;
   private readonly workerSet: Set<WorkerSetElement>;
+  private started: boolean;
   private workerStartup: boolean;
 
   /**
@@ -41,14 +42,11 @@ export class WorkerSet extends WorkerAbstract<WorkerData> {
     if (this.workerOptions.elementsPerWorker <= 0) {
       throw new RangeError('Elements per worker must be greater than zero');
     }
-    this.workerOptions.poolOptions = {
-      ...DEFAULT_POOL_OPTIONS,
-      ...this.workerOptions.poolOptions,
-    };
     this.workerSet = new Set<WorkerSetElement>();
     if (this.workerOptions.poolOptions?.enableEvents) {
-      this.emitter = new EventEmitter();
+      this.emitter = new EventEmitterAsyncResource({ name: 'workerset' });
     }
+    this.started = false;
     this.workerStartup = false;
   }
 
@@ -78,7 +76,10 @@ 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(randomizeDelay(this.workerOptions.workerStartDelay!)));
+    this.emitter?.emit(WorkerSetEvents.started, this.info);
+    this.started = true;
   }
 
   /** @inheritDoc */
@@ -86,19 +87,26 @@ export class WorkerSet extends WorkerAbstract<WorkerData> {
     for (const workerSetElement of this.workerSet) {
       const worker = workerSetElement.worker;
       const waitWorkerExit = new Promise<void>((resolve) => {
-        worker.on('exit', () => {
+        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.workerSet) {
-      throw new Error("Cannot add a WorkerSet element: workers' set does not exist");
+    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({
@@ -108,7 +116,7 @@ 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!);
+      await sleep(randomizeDelay(this.workerOptions.elementStartDelay!));
     }
   }
 
@@ -132,7 +140,11 @@ export class WorkerSet extends WorkerAbstract<WorkerData> {
     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.workerStartup) {
+      if (
+        this.workerOptions.poolOptions?.restartWorkerOnError &&
+        this.started &&
+        !this.workerStartup
+      ) {
         this.addWorkerSetElement();
       }
     });
@@ -141,9 +153,9 @@ export class WorkerSet extends WorkerAbstract<WorkerData> {
     worker.once('exit', () =>
       this.removeWorkerSetElement(this.getWorkerSetElementByWorker(worker)!),
     );
-    this.workerStartup = false;
     const workerSetElement: WorkerSetElement = { worker, numberOfWorkerElements: 0 };
     this.workerSet.add(workerSetElement);
+    this.workerStartup = false;
     return workerSetElement;
   }
 
@@ -163,7 +175,7 @@ export class WorkerSet extends WorkerAbstract<WorkerData> {
       chosenWorkerSetElement = this.addWorkerSetElement();
       // Add worker set element sequentially to optimize memory at startup
       this.workerOptions.workerStartDelay! > 0 &&
-        (await sleep(this.workerOptions.workerStartDelay!));
+        (await sleep(randomizeDelay(this.workerOptions.workerStartDelay!)));
     }
     return chosenWorkerSetElement;
   }