| 1 | import type { Worker } from 'cluster' |
| 2 | import type { JSONValue, MessageValue } from '../../utility-types' |
| 3 | import type { ClusterPoolOptions } from './fixed' |
| 4 | import { FixedClusterPool } from './fixed' |
| 5 | |
| 6 | /** |
| 7 | * A cluster pool with a min/max number of workers, is possible to execute tasks in sync or async mode as you prefer. |
| 8 | * |
| 9 | * This cluster pool will create new workers when the other ones are busy, until the max number of workers, |
| 10 | * when the max number of workers is reached, an event will be emitted, if you want to listen this event use the emitter method. |
| 11 | * |
| 12 | * @author [Christopher Quadflieg](https://github.com/Shinigami92) |
| 13 | * @since 2.0.0 |
| 14 | */ |
| 15 | export class DynamicClusterPool< |
| 16 | Data extends JSONValue = JSONValue, |
| 17 | Response extends JSONValue = JSONValue |
| 18 | > extends FixedClusterPool<Data, Response> { |
| 19 | /** |
| 20 | * @param min Min number of workers that will be always active |
| 21 | * @param max Max number of workers that will be active |
| 22 | * @param filename A file path with implementation of `ClusterWorker` class, relative path is fine. |
| 23 | * @param opts An object with possible options for example `errorHandler`, `onlineHandler`. Default: `{ maxTasks: 1000 }` |
| 24 | */ |
| 25 | public constructor ( |
| 26 | min: number, |
| 27 | public readonly max: number, |
| 28 | filename: string, |
| 29 | opts: ClusterPoolOptions = { maxTasks: 1000 } |
| 30 | ) { |
| 31 | super(min, filename, opts) |
| 32 | } |
| 33 | |
| 34 | protected chooseWorker (): Worker { |
| 35 | let worker: Worker | undefined |
| 36 | for (const entry of this.tasks) { |
| 37 | if (entry[1] === 0) { |
| 38 | worker = entry[0] |
| 39 | break |
| 40 | } |
| 41 | } |
| 42 | |
| 43 | if (worker) { |
| 44 | // a worker is free, use it |
| 45 | return worker |
| 46 | } else { |
| 47 | if (this.workers.length === this.max) { |
| 48 | this.emitter.emit('FullPool') |
| 49 | return super.chooseWorker() |
| 50 | } |
| 51 | // all workers are busy create a new worker |
| 52 | const worker = this.internalNewWorker() |
| 53 | worker.on('message', (message: MessageValue<Data>) => { |
| 54 | if (message.kill) { |
| 55 | this.sendToWorker(worker, { kill: 1 }) |
| 56 | void this.destroyWorker(worker) |
| 57 | this.removeWorker(worker) |
| 58 | } |
| 59 | }) |
| 60 | return worker |
| 61 | } |
| 62 | } |
| 63 | } |