src/pools/cluster/fixed.ts

   1 import cluster, { type ClusterSettings, type Worker } from 'node:cluster'
   2 import type { MessageValue } from '../../utility-types'
   3 import { AbstractPool } from '../abstract-pool'
   4 import {
   5   type PoolOptions,
   6   type PoolType,
   7   PoolTypes,
   8   type WorkerType,
   9   WorkerTypes
  10 } from '../pool'
  11
  12 /**
  13  * Options for a poolifier cluster pool.
  14  */
  15 export interface ClusterPoolOptions extends PoolOptions<Worker> {
  16   /**
  17    * Key/value pairs to add to worker process environment.
  18    *
  19    * @see https://nodejs.org/api/cluster.html#cluster_cluster_fork_env
  20    */
  21   env?: Record<string, unknown>
  22   /**
  23    * Cluster settings.
  24    *
  25    * @see https://nodejs.org/api/cluster.html#cluster_cluster_settings
  26    */
  27   settings?: ClusterSettings
  28 }
  29
  30 /**
  31  * A cluster pool with a fixed number of workers.
  32  *
  33  * It is possible to perform tasks in sync or asynchronous mode as you prefer.
  34  *
  35  * This pool selects the workers in a round robin fashion.
  36  *
  37  * @typeParam Data - Type of data sent to the worker. This can only be serializable data.
  38  * @typeParam Response - Type of execution response. This can only be serializable data.
  39  * @author [Christopher Quadflieg](https://github.com/Shinigami92)
  40  * @since 2.0.0
  41  */
  42 export class FixedClusterPool<
  43   Data = unknown,
  44   Response = unknown
  45 > extends AbstractPool<Worker, Data, Response> {
  46   /**
  47    * Constructs a new poolifier fixed cluster pool.
  48    *
  49    * @param numberOfWorkers - Number of workers for this pool.
  50    * @param filePath - Path to an implementation of a `ClusterWorker` file, which can be relative or absolute.
  51    * @param opts - Options for this fixed cluster pool.
  52    */
  53   public constructor (
  54     numberOfWorkers: number,
  55     filePath: string,
  56     protected readonly opts: ClusterPoolOptions = {}
  57   ) {
  58     super(numberOfWorkers, filePath, opts)
  59   }
  60
  61   /** @inheritDoc */
  62   protected setupHook (): void {
  63     cluster.setupPrimary({ ...this.opts.settings, exec: this.filePath })
  64   }
  65
  66   /** @inheritDoc */
  67   protected isMain (): boolean {
  68     return cluster.isPrimary
  69   }
  70
  71   /** @inheritDoc */
  72   protected destroyWorker (worker: Worker): void {
  73     this.sendToWorker(worker, { kill: 1 })
  74     worker.kill()
  75   }
  76
  77   /** @inheritDoc */
  78   protected sendToWorker (worker: Worker, message: MessageValue<Data>): void {
  79     worker.send(message)
  80   }
  81
  82   /** @inheritDoc */
  83   protected registerWorkerMessageListener<Message extends Data | Response>(
  84     worker: Worker,
  85     listener: (message: MessageValue<Message>) => void
  86   ): void {
  87     worker.on('message', listener)
  88   }
  89
  90   /** @inheritDoc */
  91   protected createWorker (): Worker {
  92     return cluster.fork(this.opts.env)
  93   }
  94
  95   /** @inheritDoc */
  96   protected afterWorkerSetup (worker: Worker): void {
  97     // Listen to worker messages.
  98     this.registerWorkerMessageListener(worker, super.workerListener())
  99   }
 100
 101   /** @inheritDoc */
 102   protected get type (): PoolType {
 103     return PoolTypes.fixed
 104   }
 105
 106   /** @inheritDoc */
 107   protected get worker (): WorkerType {
 108     return WorkerTypes.cluster
 109   }
 110
 111   /** @inheritDoc */
 112   protected get minSize (): number {
 113     return this.numberOfWorkers
 114   }
 115
 116   /** @inheritDoc */
 117   protected get maxSize (): number {
 118     return this.numberOfWorkers
 119   }
 120
 121   /** @inheritDoc */
 122   protected get busy (): boolean {
 123     return this.internalBusy()
 124   }
 125 }