src/pools/pool-internal.ts

   1 import EventEmitter from 'events'
   2 import type { IWorker } from './abstract-pool'
   3 import type { IPool } from './pool'
   4
   5 /**
   6  * Pool types.
   7  */
   8 export enum PoolType {
   9   FIXED = 'fixed',
  10   DYNAMIC = 'dynamic'
  11 }
  12
  13 /**
  14  * Internal poolifier pool emitter.
  15  */
  16 export class PoolEmitter extends EventEmitter {}
  17
  18 /**
  19  * Internal contract definition for a poolifier pool.
  20  *
  21  * @template Worker Type of worker which manages this pool.
  22  * @template Data Type of data sent to the worker.
  23  * @template Response Type of response of execution.
  24  */
  25 export interface IPoolInternal<
  26   Worker extends IWorker,
  27   Data = unknown,
  28   Response = unknown
  29 > extends IPool<Data, Response> {
  30   /**
  31    * List of currently available workers.
  32    */
  33   readonly workers: Worker[]
  34
  35   /**
  36    * The tasks map.
  37    *
  38    * - `key`: The `Worker`
  39    * - `value`: Number of tasks currently in progress on the worker.
  40    */
  41   readonly tasks: Map<Worker, number>
  42
  43   /**
  44    * Emitter on which events can be listened to.
  45    *
  46    * Events that can currently be listened to:
  47    *
  48    * - `'busy'`
  49    */
  50   readonly emitter?: PoolEmitter
  51
  52   /**
  53    * Pool type.
  54    *
  55    * If it is `'dynamic'`, it provides the `max` property.
  56    */
  57   readonly type: PoolType
  58
  59   /**
  60    * Maximum number of workers that can be created by this pool.
  61    */
  62   readonly max?: number
  63
  64   /**
  65    * Whether the pool is busy or not.
  66    *
  67    * The pool busyness boolean status.
  68    */
  69   readonly busy: boolean
  70
  71   /**
  72    * Number of tasks currently concurrently running.
  73    */
  74   readonly numberOfRunningTasks: number
  75
  76   /**
  77    * Find a tasks map entry with a free worker based on the number of tasks the worker has applied.
  78    *
  79    * If an entry is found with a worker that has `0` tasks, it is detected as free.
  80    *
  81    * If no tasks map entry with a free worker was found, `false` will be returned.
  82    *
  83    * @returns A tasks map entry with a free worker if there was one, otherwise `false`.
  84    */
  85   findFreeTasksMapEntry(): [Worker, number] | false
  86 }