src/pools/selection-strategies/abstract-worker-choice-strategy.ts

   1 import { DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS } from '../../utils'
   2 import { PoolType, type IPool } from '../pool'
   3 import type { IWorker } from '../worker'
   4 import type {
   5   IWorkerChoiceStrategy,
   6   RequiredStatistics,
   7   WorkerChoiceStrategyOptions
   8 } from './selection-strategies-types'
   9
  10 /**
  11  * Worker choice strategy abstract base class.
  12  *
  13  * @typeParam Worker - Type of worker which manages the strategy.
  14  * @typeParam Data - Type of data sent to the worker. This can only be serializable data.
  15  * @typeParam Response - Type of execution response. This can only be serializable data.
  16  */
  17 export abstract class AbstractWorkerChoiceStrategy<
  18   Worker extends IWorker,
  19   Data = unknown,
  20   Response = unknown
  21 > implements IWorkerChoiceStrategy {
  22   /**
  23    * Toggles finding the last free worker node key.
  24    */
  25   private toggleFindLastFreeWorkerNodeKey: boolean = false
  26   /** @inheritDoc */
  27   protected readonly isDynamicPool: boolean
  28   /** @inheritDoc */
  29   public readonly requiredStatistics: RequiredStatistics = {
  30     runTime: false,
  31     avgRunTime: false,
  32     medRunTime: false
  33   }
  34
  35   /**
  36    * Constructs a worker choice strategy bound to the pool.
  37    *
  38    * @param pool - The pool instance.
  39    * @param opts - The worker choice strategy options.
  40    */
  41   public constructor (
  42     protected readonly pool: IPool<Worker, Data, Response>,
  43     protected opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
  44   ) {
  45     this.isDynamicPool = this.pool.type === PoolType.DYNAMIC
  46     this.choose = this.choose.bind(this)
  47   }
  48
  49   protected checkOptions (opts: WorkerChoiceStrategyOptions): void {
  50     if (this.requiredStatistics.avgRunTime && opts.medRunTime === true) {
  51       this.requiredStatistics.avgRunTime = false
  52       this.requiredStatistics.medRunTime = opts.medRunTime as boolean
  53     }
  54     if (this.requiredStatistics.medRunTime && opts.medRunTime === false) {
  55       this.requiredStatistics.avgRunTime = true
  56       this.requiredStatistics.medRunTime = opts.medRunTime as boolean
  57     }
  58   }
  59
  60   /** @inheritDoc */
  61   public abstract reset (): boolean
  62
  63   /** @inheritDoc */
  64   public abstract choose (): number
  65
  66   /** @inheritDoc */
  67   public abstract remove (workerNodeKey: number): boolean
  68
  69   /** @inheritDoc */
  70   public setOptions (opts: WorkerChoiceStrategyOptions): void {
  71     opts = opts ?? DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
  72     this.checkOptions(opts)
  73     this.opts = opts
  74   }
  75
  76   /**
  77    * Finds a free worker node key.
  78    *
  79    * @returns The free worker node key or `-1` if there is no free worker node.
  80    */
  81   protected findFreeWorkerNodeKey (): number {
  82     if (this.toggleFindLastFreeWorkerNodeKey) {
  83       this.toggleFindLastFreeWorkerNodeKey = false
  84       return this.pool.findLastFreeWorkerNodeKey()
  85     }
  86     this.toggleFindLastFreeWorkerNodeKey = true
  87     return this.pool.findFreeWorkerNodeKey()
  88   }
  89 }