src/pools/cluster/fixed.ts

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