| 1 | import { AsyncResource } from 'async_hooks' |
| 2 | import type { MessageValue } from '../utility-types' |
| 3 | import type { WorkerOptions } from './worker-options' |
| 4 | |
| 5 | export abstract class AbstractWorker< |
| 6 | MainWorker, |
| 7 | Data = unknown, |
| 8 | Response = unknown |
| 9 | > extends AsyncResource { |
| 10 | protected readonly maxInactiveTime: number |
| 11 | protected readonly async: boolean |
| 12 | protected lastTask: number |
| 13 | protected readonly interval?: NodeJS.Timeout |
| 14 | |
| 15 | /** |
| 16 | * |
| 17 | * @param type The type of async event. |
| 18 | * @param isMain |
| 19 | * @param fn |
| 20 | * @param opts |
| 21 | */ |
| 22 | public constructor ( |
| 23 | type: string, |
| 24 | isMain: boolean, |
| 25 | fn: (data: Data) => Response, |
| 26 | public readonly opts: WorkerOptions = {} |
| 27 | ) { |
| 28 | super(type) |
| 29 | |
| 30 | this.maxInactiveTime = this.opts.maxInactiveTime ?? 1000 * 60 |
| 31 | this.async = !!this.opts.async |
| 32 | this.lastTask = Date.now() |
| 33 | if (!fn) throw new Error('fn parameter is mandatory') |
| 34 | // keep the worker active |
| 35 | if (!isMain) { |
| 36 | this.interval = setInterval( |
| 37 | this.checkAlive.bind(this), |
| 38 | this.maxInactiveTime / 2 |
| 39 | ) |
| 40 | this.checkAlive.bind(this)() |
| 41 | } |
| 42 | } |
| 43 | |
| 44 | protected abstract getMainWorker (): MainWorker |
| 45 | |
| 46 | protected abstract sendToMainWorker (message: MessageValue<Response>): void |
| 47 | |
| 48 | protected checkAlive (): void { |
| 49 | if (Date.now() - this.lastTask > this.maxInactiveTime) { |
| 50 | this.sendToMainWorker({ kill: 1 }) |
| 51 | } |
| 52 | } |
| 53 | |
| 54 | protected handleError (e: Error | string): string { |
| 55 | return (e as unknown) as string |
| 56 | } |
| 57 | |
| 58 | protected run ( |
| 59 | fn: (data?: Data) => Response, |
| 60 | value: MessageValue<Data> |
| 61 | ): void { |
| 62 | try { |
| 63 | const res = fn(value.data) |
| 64 | this.sendToMainWorker({ data: res, id: value.id }) |
| 65 | this.lastTask = Date.now() |
| 66 | } catch (e) { |
| 67 | const err = this.handleError(e) |
| 68 | this.sendToMainWorker({ error: err, id: value.id }) |
| 69 | this.lastTask = Date.now() |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | protected runAsync ( |
| 74 | fn: (data?: Data) => Promise<Response>, |
| 75 | value: MessageValue<Data> |
| 76 | ): void { |
| 77 | fn(value.data) |
| 78 | .then(res => { |
| 79 | this.sendToMainWorker({ data: res, id: value.id }) |
| 80 | this.lastTask = Date.now() |
| 81 | return null |
| 82 | }) |
| 83 | .catch(e => { |
| 84 | const err = this.handleError(e) |
| 85 | this.sendToMainWorker({ error: err, id: value.id }) |
| 86 | this.lastTask = Date.now() |
| 87 | }) |
| 88 | } |
| 89 | } |