src/pools/worker.ts

   1 import type { CircularArray } from '../circular-array'
   2
   3 /**
   4  * Callback invoked if the worker has received a message.
   5  */
   6 export type MessageHandler<Worker extends IWorker> = (
   7   this: Worker,
   8   m: unknown
   9 ) => void
  10
  11 /**
  12  * Callback invoked if the worker raised an error.
  13  */
  14 export type ErrorHandler<Worker extends IWorker> = (
  15   this: Worker,
  16   e: Error
  17 ) => void
  18
  19 /**
  20  * Callback invoked when the worker has started successfully.
  21  */
  22 export type OnlineHandler<Worker extends IWorker> = (this: Worker) => void
  23
  24 /**
  25  * Callback invoked when the worker exits successfully.
  26  */
  27 export type ExitHandler<Worker extends IWorker> = (
  28   this: Worker,
  29   code: number
  30 ) => void
  31
  32 /**
  33  * Worker task interface.
  34  */
  35 export interface Task<Data = unknown> {
  36   data: Data
  37   id: string
  38 }
  39
  40 /**
  41  * Worker tasks usage statistics.
  42  */
  43 export interface TasksUsage {
  44   run: number
  45   running: number
  46   runTime: number
  47   runTimeHistory: CircularArray<number>
  48   avgRunTime: number
  49   medRunTime: number
  50   error: number
  51 }
  52
  53 /**
  54  * Worker interface.
  55  */
  56 export interface IWorker {
  57   /**
  58    * Register an event listener.
  59    *
  60    * @param event - The event.
  61    * @param handler - The event listener.
  62    */
  63   on: ((event: 'message', handler: MessageHandler<this>) => void) &
  64   ((event: 'error', handler: ErrorHandler<this>) => void) &
  65   ((event: 'online', handler: OnlineHandler<this>) => void) &
  66   ((event: 'exit', handler: ExitHandler<this>) => void)
  67   /**
  68    * Register a listener to the exit event that will only performed once.
  69    *
  70    * @param event - `'exit'`.
  71    * @param handler - The exit handler.
  72    */
  73   once: (event: 'exit', handler: ExitHandler<this>) => void
  74 }
  75
  76 /**
  77  * Worker node interface.
  78  */
  79 export interface WorkerNode<Worker extends IWorker, Data = unknown> {
  80   worker: Worker
  81   tasksUsage: TasksUsage
  82   tasksQueue: Array<Task<Data>>
  83 }