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