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   /**
  37    * Worker task data.
  38    */
  39   data: Data
  40   /**
  41    * Task UUID.
  42    */
  43   id: string
  44 }
  45
  46 /**
  47  * Worker tasks usage statistics.
  48  */
  49 export interface TasksUsage {
  50   run: number
  51   running: number
  52   runTime: number
  53   runTimeHistory: CircularArray<number>
  54   avgRunTime: number
  55   medRunTime: number
  56   error: number
  57 }
  58
  59 /**
  60  * Worker interface.
  61  */
  62 export interface IWorker {
  63   /**
  64    * Register an event listener.
  65    *
  66    * @param event - The event.
  67    * @param handler - The event listener.
  68    */
  69   on: ((event: 'message', handler: MessageHandler<this>) => void) &
  70   ((event: 'error', handler: ErrorHandler<this>) => void) &
  71   ((event: 'online', handler: OnlineHandler<this>) => void) &
  72   ((event: 'exit', handler: ExitHandler<this>) => void)
  73   /**
  74    * Register a listener to the exit event that will only performed once.
  75    *
  76    * @param event - `'exit'`.
  77    * @param handler - The exit handler.
  78    */
  79   once: (event: 'exit', handler: ExitHandler<this>) => void
  80 }
  81
  82 /**
  83  * Worker node interface.
  84  */
  85 export interface WorkerNode<Worker extends IWorker, Data = unknown> {
  86   worker: Worker
  87   tasksUsage: TasksUsage
  88   tasksQueue: Array<Task<Data>>
  89 }