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 { type PoolOptions, type PoolType, PoolTypes } from '../pool'
   5 import { type WorkerType, WorkerTypes } from '../worker'
   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   env?: Record<string, unknown>
  17   /**
  18    * Cluster settings.
  19    *
  20    * @see https://nodejs.org/api/cluster.html#cluster_cluster_settings
  21    */
  22   settings?: ClusterSettings
  23 }
  24
  25 /**
  26  * A cluster pool with a fixed number of workers.
  27  *
  28  * @typeParam Data - Type of data sent to the worker. This can only be structured-cloneable data.
  29  * @typeParam Response - Type of execution response. This can only be structured-cloneable data.
  30  * @author [Christopher Quadflieg](https://github.com/Shinigami92)
  31  * @since 2.0.0
  32  */
  33 export class FixedClusterPool<
  34   Data = unknown,
  35   Response = unknown
  36 > extends AbstractPool<Worker, Data, Response> {
  37   /**
  38    * Constructs a new poolifier fixed cluster pool.
  39    *
  40    * @param numberOfWorkers - Number of workers for this pool.
  41    * @param filePath - Path to an implementation of a `ClusterWorker` file, which can be relative or absolute.
  42    * @param opts - Options for this fixed cluster pool.
  43    */
  44   public constructor (
  45     numberOfWorkers: number,
  46     filePath: string,
  47     protected readonly opts: ClusterPoolOptions = {}
  48   ) {
  49     super(numberOfWorkers, filePath, opts)
  50   }
  51
  52   /** @inheritDoc */
  53   protected setupHook (): void {
  54     cluster.setupPrimary({ ...this.opts.settings, exec: this.filePath })
  55   }
  56
  57   /** @inheritDoc */
  58   protected isMain (): boolean {
  59     return cluster.isPrimary
  60   }
  61
  62   /** @inheritDoc */
  63   protected async destroyWorkerNode (workerNodeKey: number): Promise<void> {
  64     this.flushTasksQueue(workerNodeKey)
  65     // FIXME: wait for tasks to be finished
  66     const worker = this.workerNodes[workerNodeKey].worker
  67     const workerExitPromise = new Promise<void>(resolve => {
  68       worker.on('exit', () => {
  69         resolve()
  70       })
  71     })
  72     worker.on('disconnect', () => {
  73       worker.kill()
  74     })
  75     this.sendToWorker(workerNodeKey, { kill: true, workerId: worker.id })
  76     worker.disconnect()
  77     await workerExitPromise
  78   }
  79
  80   /** @inheritDoc */
  81   protected sendToWorker (
  82     workerNodeKey: number,
  83     message: MessageValue<Data>
  84   ): void {
  85     this.workerNodes[workerNodeKey].worker.send(message)
  86   }
  87
  88   /** @inheritDoc */
  89   protected sendStartupMessageToWorker (workerNodeKey: number): void {
  90     this.sendToWorker(workerNodeKey, {
  91       ready: false,
  92       workerId: this.workerNodes[workerNodeKey].worker.id
  93     })
  94   }
  95
  96   /** @inheritDoc */
  97   protected registerWorkerMessageListener<Message extends Data | Response>(
  98     workerNodeKey: number,
  99     listener: (message: MessageValue<Message>) => void
 100   ): void {
 101     this.workerNodes[workerNodeKey].worker.on('message', listener)
 102   }
 103
 104   /** @inheritDoc */
 105   protected createWorker (): Worker {
 106     return cluster.fork(this.opts.env)
 107   }
 108
 109   /** @inheritDoc */
 110   protected get type (): PoolType {
 111     return PoolTypes.fixed
 112   }
 113
 114   /** @inheritDoc */
 115   protected get worker (): WorkerType {
 116     return WorkerTypes.cluster
 117   }
 118
 119   /** @inheritDoc */
 120   protected get minSize (): number {
 121     return this.numberOfWorkers
 122   }
 123
 124   /** @inheritDoc */
 125   protected get maxSize (): number {
 126     return this.numberOfWorkers
 127   }
 128
 129   /** @inheritDoc */
 130   protected get busy (): boolean {
 131     return this.internalBusy()
 132   }
 133 }