src/pools/cluster/fixed.ts

   1 import { fork, isMaster, setupMaster, Worker } from 'cluster'
   2 import type { MessageValue } from '../../utility-types'
   3 import type { PoolOptions } from '../abstract-pool'
   4 import { AbstractPool } from '../abstract-pool'
   5 import { PoolType } from '../pool-internal'
   6
   7 /**
   8  * Options for a poolifier cluster pool.
   9  */
  10 export interface ClusterPoolOptions extends PoolOptions<Worker> {
  11   /**
  12    * Key/value pairs to add to worker process environment.
  13    *
  14    * @see https://nodejs.org/api/cluster.html#cluster_cluster_fork_env
  15    */
  16   // eslint-disable-next-line @typescript-eslint/no-explicit-any
  17   env?: any
  18 }
  19
  20 /**
  21  * A cluster pool with a fixed number of workers.
  22  *
  23  * It is possible to perform tasks in sync or asynchronous mode as you prefer.
  24  *
  25  * This pool selects the workers in a round robin fashion.
  26  *
  27  * @template DataType of data sent to the worker. This can only be serializable data.
  28  * @template ResponseType of response of execution. This can only be serializable data.
  29  * @author [Christopher Quadflieg](https://github.com/Shinigami92)
  30  * @since 2.0.0
  31  */
  32 export class FixedClusterPool<
  33   Data = unknown,
  34   Response = unknown
  35 > extends AbstractPool<Worker, Data, Response> {
  36   /**
  37    * Constructs a new poolifier fixed cluster pool.
  38    *
  39    * @param numberOfWorkers Number of workers for this pool.
  40    * @param filePath Path to an implementation of a `ClusterWorker` file, which can be relative or absolute.
  41    * @param [opts={}] Options for this fixed cluster pool.
  42    */
  43   public constructor (
  44     numberOfWorkers: number,
  45     filePath: string,
  46     public readonly opts: ClusterPoolOptions = {}
  47   ) {
  48     super(numberOfWorkers, filePath, opts)
  49   }
  50
  51   /** @inheritdoc */
  52   protected setupHook (): void {
  53     setupMaster({
  54       exec: this.filePath
  55     })
  56   }
  57
  58   /** @inheritdoc */
  59   protected isMain (): boolean {
  60     return isMaster
  61   }
  62
  63   /** @inheritdoc */
  64   public destroyWorker (worker: Worker): void {
  65     this.sendToWorker(worker, { kill: 1 })
  66     worker.kill()
  67   }
  68
  69   /** @inheritdoc */
  70   protected sendToWorker (worker: Worker, message: MessageValue<Data>): void {
  71     worker.send(message)
  72   }
  73
  74   /** @inheritdoc */
  75   public registerWorkerMessageListener<Message extends Data | Response> (
  76     worker: Worker,
  77     listener: (message: MessageValue<Message>) => void
  78   ): void {
  79     worker.on('message', listener)
  80   }
  81
  82   /** @inheritdoc */
  83   protected createWorker (): Worker {
  84     return fork(this.opts.env)
  85   }
  86
  87   /** @inheritdoc */
  88   protected afterWorkerSetup (worker: Worker): void {
  89     // Listen worker messages.
  90     this.registerWorkerMessageListener(worker, super.workerListener())
  91   }
  92
  93   /** @inheritdoc */
  94   public get type (): PoolType {
  95     return PoolType.FIXED
  96   }
  97
  98   /** @inheritdoc */
  99   public get busy (): boolean {
 100     return this.internalGetBusyStatus()
 101   }
 102 }