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   // eslint-disable-next-line @typescript-eslint/no-explicit-any
  22   env?: any
  23   /**
  24    * Cluster settings.
  25    *
  26    * @see https://nodejs.org/api/cluster.html#cluster_cluster_settings
  27    */
  28   settings?: ClusterSettings
  29 }
  30
  31 /**
  32  * A cluster pool with a fixed number of workers.
  33  *
  34  * It is possible to perform tasks in sync or asynchronous mode as you prefer.
  35  *
  36  * This pool selects the workers in a round robin fashion.
  37  *
  38  * @typeParam Data - Type of data sent to the worker. This can only be serializable data.
  39  * @typeParam Response - Type of execution response. This can only be serializable data.
  40  * @author [Christopher Quadflieg](https://github.com/Shinigami92)
  41  * @since 2.0.0
  42  */
  43 export class FixedClusterPool<
  44   Data = unknown,
  45   Response = unknown
  46 > extends AbstractPool<Worker, Data, Response> {
  47   /**
  48    * Constructs a new poolifier fixed cluster pool.
  49    *
  50    * @param numberOfWorkers - Number of workers for this pool.
  51    * @param filePath - Path to an implementation of a `ClusterWorker` file, which can be relative or absolute.
  52    * @param opts - Options for this fixed cluster pool.
  53    */
  54   public constructor (
  55     numberOfWorkers: number,
  56     filePath: string,
  57     public readonly opts: ClusterPoolOptions = {}
  58   ) {
  59     super(numberOfWorkers, filePath, opts)
  60   }
  61
  62   /** @inheritDoc */
  63   protected setupHook (): void {
  64     cluster.setupPrimary({ ...this.opts.settings, exec: this.filePath })
  65   }
  66
  67   /** @inheritDoc */
  68   protected isMain (): boolean {
  69     return cluster.isPrimary
  70   }
  71
  72   /** @inheritDoc */
  73   protected destroyWorker (worker: Worker): void {
  74     this.sendToWorker(worker, { kill: 1 })
  75     worker.kill()
  76   }
  77
  78   /** @inheritDoc */
  79   protected sendToWorker (worker: Worker, message: MessageValue<Data>): void {
  80     worker.send(message)
  81   }
  82
  83   /** @inheritDoc */
  84   protected registerWorkerMessageListener<Message extends Data | Response>(
  85     worker: Worker,
  86     listener: (message: MessageValue<Message>) => void
  87   ): void {
  88     worker.on('message', listener)
  89   }
  90
  91   /** @inheritDoc */
  92   protected createWorker (): Worker {
  93     return cluster.fork(this.opts.env)
  94   }
  95
  96   /** @inheritDoc */
  97   protected afterWorkerSetup (worker: Worker): void {
  98     // Listen to worker messages.
  99     this.registerWorkerMessageListener(worker, super.workerListener())
 100   }
 101
 102   /** @inheritDoc */
 103   public get type (): PoolType {
 104     return PoolTypes.fixed
 105   }
 106
 107   /** @inheritDoc */
 108   protected get worker (): WorkerType {
 109     return WorkerTypes.cluster
 110   }
 111
 112   /** @inheritDoc */
 113   protected get minSize (): number {
 114     return this.numberOfWorkers
 115   }
 116
 117   /** @inheritDoc */
 118   protected get maxSize (): number {
 119     return this.numberOfWorkers
 120   }
 121
 122   /** @inheritDoc */
 123   protected get full (): boolean {
 124     return this.workerNodes.length >= this.numberOfWorkers
 125   }
 126
 127   /** @inheritDoc */
 128   protected get busy (): boolean {
 129     return this.internalBusy()
 130   }
 131 }