src/worker/thread-worker.ts

   1 import { isMainThread, parentPort } from 'worker_threads'
   2 import type { JSONValue, MessageValue } from '../utility-types'
   3 import { AbstractWorker } from './abstract-worker'
   4 import type { WorkerOptions } from './worker-options'
   5
   6 /**
   7  * An example worker that will be always alive, you just need to **extend** this class if you want a static pool.
   8  *
   9  * When this worker is inactive for more than 1 minute, it will send this info to the main thread,
  10  * if you are using DynamicThreadPool, the workers created after will be killed, the min num of thread will be guaranteed.
  11  *
  12  * @author [Alessandro Pio Ardizio](https://github.com/pioardi)
  13  * @since 0.0.1
  14  */
  15 export class ThreadWorker<
  16   Data extends JSONValue = JSONValue,
  17   Response extends JSONValue = JSONValue
  18 > extends AbstractWorker<MessagePort, Data, Response> {
  19   protected parent?: MessagePort
  20
  21   public constructor (fn: (data: Data) => Response, opts: WorkerOptions = {}) {
  22     super('worker-thread-pool:pioardi', isMainThread, fn, opts)
  23
  24     parentPort?.on('message', (value: MessageValue<Data>) => {
  25       if (value?.data && value.id) {
  26         // here you will receive messages
  27         // console.log('This is the main worker ' + isMain)
  28         if (this.async) {
  29           this.runInAsyncScope(this.runAsync.bind(this), this, fn, value)
  30         } else {
  31           this.runInAsyncScope(this.run.bind(this), this, fn, value)
  32         }
  33       } else if (value.parent) {
  34         // save the port to communicate with the main thread
  35         // this will be received once
  36         this.parent = value.parent
  37       } else if (value.kill) {
  38         // here is time to kill this worker, just clearing the interval
  39         if (this.interval) clearInterval(this.interval)
  40         this.emitDestroy()
  41       }
  42     })
  43   }
  44
  45   protected getMainWorker (): MessagePort {
  46     if (!this.parent) {
  47       throw new Error('Parent was not set')
  48     }
  49     return this.parent
  50   }
  51
  52   protected sendToMainWorker (message: MessageValue<Response>): void {
  53     this.getMainWorker().postMessage(message)
  54   }
  55 }