src/worker/WorkerAbstract.ts

   1 import type EventEmitterAsyncResource from 'node:events';
   2 import fs from 'node:fs';
   3
   4 import { WorkerConstants } from './WorkerConstants';
   5 import type { WorkerData, WorkerOptions } from './WorkerTypes';
   6
   7 export abstract class WorkerAbstract<T extends WorkerData> {
   8   protected readonly workerScript: string;
   9   protected readonly workerOptions: WorkerOptions;
  10   public abstract readonly size: number;
  11   public abstract readonly maxElementsPerWorker: number | undefined;
  12   public abstract readonly emitter: EventEmitterAsyncResource | undefined;
  13
  14   /**
  15    * `WorkerAbstract` constructor.
  16    *
  17    * @param workerScript -
  18    * @param workerOptions -
  19    */
  20   constructor(
  21     workerScript: string,
  22     workerOptions: WorkerOptions = {
  23       workerStartDelay: WorkerConstants.DEFAULT_WORKER_START_DELAY,
  24       elementStartDelay: WorkerConstants.DEFAULT_ELEMENT_START_DELAY,
  25       poolMinSize: WorkerConstants.DEFAULT_POOL_MIN_SIZE,
  26       poolMaxSize: WorkerConstants.DEFAULT_POOL_MAX_SIZE,
  27       elementsPerWorker: WorkerConstants.DEFAULT_ELEMENTS_PER_WORKER,
  28       poolOptions: {},
  29       messageHandler: WorkerConstants.EMPTY_FUNCTION,
  30     }
  31   ) {
  32     if (workerScript === null || workerScript === undefined) {
  33       throw new Error('Worker script is not defined');
  34     }
  35     if (typeof workerScript === 'string' && workerScript.trim().length === 0) {
  36       throw new Error('Worker script is empty');
  37     }
  38     if (!fs.existsSync(workerScript)) {
  39       throw new Error('Worker script file does not exist');
  40     }
  41     this.workerScript = workerScript;
  42     this.workerOptions = workerOptions;
  43   }
  44
  45   /**
  46    * Start the worker pool/set.
  47    */
  48   public abstract start(): Promise<void>;
  49   /**
  50    * Stop the worker pool/set.
  51    */
  52   public abstract stop(): Promise<void>;
  53   /**
  54    * Add a task element to the worker pool/set.
  55    *
  56    * @param elementData -
  57    */
  58   public abstract addElement(elementData: T): Promise<void>;
  59 }