src/worker/WorkerDynamicPool.ts

   1 import type EventEmitterAsyncResource from 'node:events';
   2 import type { Worker } from 'node:worker_threads';
   3
   4 import { DynamicThreadPool, type ErrorHandler, type ExitHandler } from 'poolifier';
   5
   6 import { WorkerAbstract } from './WorkerAbstract';
   7 import type { WorkerData, WorkerOptions } from './WorkerTypes';
   8 import { defaultErrorHandler, defaultExitHandler, sleep } from './WorkerUtils';
   9
  10 export class WorkerDynamicPool extends WorkerAbstract<WorkerData> {
  11   private readonly pool: DynamicThreadPool<WorkerData>;
  12
  13   /**
  14    * Create a new `WorkerDynamicPool`.
  15    *
  16    * @param workerScript -
  17    * @param workerOptions -
  18    */
  19   constructor(workerScript: string, workerOptions?: WorkerOptions) {
  20     super(workerScript, workerOptions);
  21     this.workerOptions.poolOptions.errorHandler = (
  22       this.workerOptions?.poolOptions?.errorHandler ?? defaultErrorHandler
  23     ).bind(this) as ErrorHandler<Worker>;
  24     this.workerOptions.poolOptions.exitHandler = (
  25       this.workerOptions?.poolOptions?.exitHandler ?? defaultExitHandler
  26     ).bind(this) as ExitHandler<Worker>;
  27     this.workerOptions.poolOptions.messageHandler.bind(this);
  28     this.pool = new DynamicThreadPool<WorkerData>(
  29       this.workerOptions.poolMinSize,
  30       this.workerOptions.poolMaxSize,
  31       this.workerScript,
  32       this.workerOptions.poolOptions
  33     );
  34   }
  35
  36   get size(): number {
  37     return this.pool.workerNodes.length;
  38   }
  39
  40   get maxElementsPerWorker(): number | undefined {
  41     return undefined;
  42   }
  43
  44   get emitter(): EventEmitterAsyncResource | undefined {
  45     return this.pool?.emitter;
  46   }
  47
  48   /** @inheritDoc */
  49   public async start(): Promise<void> {
  50     // This is intentional
  51   }
  52
  53   /** @inheritDoc */
  54   public async stop(): Promise<void> {
  55     return this.pool.destroy();
  56   }
  57
  58   /** @inheritDoc */
  59   public async addElement(elementData: WorkerData): Promise<void> {
  60     await this.pool.execute(elementData);
  61     // Start element sequentially to optimize memory at startup
  62     this.workerOptions.elementStartDelay > 0 && (await sleep(this.workerOptions.elementStartDelay));
  63   }
  64 }