| 1 | import { DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS } from '../../utils' |
| 2 | import type { IPool } from '../pool' |
| 3 | import type { IWorker } from '../worker' |
| 4 | import { FairShareWorkerChoiceStrategy } from './fair-share-worker-choice-strategy' |
| 5 | import { LessBusyWorkerChoiceStrategy } from './less-busy-worker-choice-strategy' |
| 6 | import { LessUsedWorkerChoiceStrategy } from './less-used-worker-choice-strategy' |
| 7 | import { RoundRobinWorkerChoiceStrategy } from './round-robin-worker-choice-strategy' |
| 8 | import type { |
| 9 | IWorkerChoiceStrategy, |
| 10 | RequiredStatistics, |
| 11 | WorkerChoiceStrategy, |
| 12 | WorkerChoiceStrategyOptions |
| 13 | } from './selection-strategies-types' |
| 14 | import { WorkerChoiceStrategies } from './selection-strategies-types' |
| 15 | import { WeightedRoundRobinWorkerChoiceStrategy } from './weighted-round-robin-worker-choice-strategy' |
| 16 | |
| 17 | /** |
| 18 | * The worker choice strategy context. |
| 19 | * |
| 20 | * @typeParam Worker - Type of worker. |
| 21 | * @typeParam Data - Type of data sent to the worker. This can only be serializable data. |
| 22 | * @typeParam Response - Type of execution response. This can only be serializable data. |
| 23 | */ |
| 24 | export class WorkerChoiceStrategyContext< |
| 25 | Worker extends IWorker, |
| 26 | Data = unknown, |
| 27 | Response = unknown |
| 28 | > { |
| 29 | private readonly workerChoiceStrategies: Map< |
| 30 | WorkerChoiceStrategy, |
| 31 | IWorkerChoiceStrategy |
| 32 | > |
| 33 | |
| 34 | /** |
| 35 | * Worker choice strategy context constructor. |
| 36 | * |
| 37 | * @param pool - The pool instance. |
| 38 | * @param workerChoiceStrategy - The worker choice strategy. |
| 39 | * @param opts - The worker choice strategy options. |
| 40 | */ |
| 41 | public constructor ( |
| 42 | pool: IPool<Worker, Data, Response>, |
| 43 | private workerChoiceStrategy: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN, |
| 44 | opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS |
| 45 | ) { |
| 46 | this.execute = this.execute.bind(this) |
| 47 | this.workerChoiceStrategies = new Map< |
| 48 | WorkerChoiceStrategy, |
| 49 | IWorkerChoiceStrategy |
| 50 | >([ |
| 51 | [ |
| 52 | WorkerChoiceStrategies.ROUND_ROBIN, |
| 53 | new (RoundRobinWorkerChoiceStrategy.bind(this))<Worker, Data, Response>( |
| 54 | pool, |
| 55 | opts |
| 56 | ) |
| 57 | ], |
| 58 | [ |
| 59 | WorkerChoiceStrategies.LESS_USED, |
| 60 | new (LessUsedWorkerChoiceStrategy.bind(this))<Worker, Data, Response>( |
| 61 | pool, |
| 62 | opts |
| 63 | ) |
| 64 | ], |
| 65 | [ |
| 66 | WorkerChoiceStrategies.LESS_BUSY, |
| 67 | new (LessBusyWorkerChoiceStrategy.bind(this))<Worker, Data, Response>( |
| 68 | pool, |
| 69 | opts |
| 70 | ) |
| 71 | ], |
| 72 | [ |
| 73 | WorkerChoiceStrategies.FAIR_SHARE, |
| 74 | new (FairShareWorkerChoiceStrategy.bind(this))<Worker, Data, Response>( |
| 75 | pool, |
| 76 | opts |
| 77 | ) |
| 78 | ], |
| 79 | [ |
| 80 | WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN, |
| 81 | new (WeightedRoundRobinWorkerChoiceStrategy.bind(this))< |
| 82 | Worker, |
| 83 | Data, |
| 84 | Response |
| 85 | >(pool, opts) |
| 86 | ] |
| 87 | ]) |
| 88 | } |
| 89 | |
| 90 | /** |
| 91 | * Gets the worker choice strategy in the context required statistics. |
| 92 | * |
| 93 | * @returns The required statistics. |
| 94 | */ |
| 95 | public getRequiredStatistics (): RequiredStatistics { |
| 96 | return ( |
| 97 | this.workerChoiceStrategies.get( |
| 98 | this.workerChoiceStrategy |
| 99 | ) as IWorkerChoiceStrategy |
| 100 | ).requiredStatistics |
| 101 | } |
| 102 | |
| 103 | /** |
| 104 | * Sets the worker choice strategy to use in the context. |
| 105 | * |
| 106 | * @param workerChoiceStrategy - The worker choice strategy to set. |
| 107 | */ |
| 108 | public setWorkerChoiceStrategy ( |
| 109 | workerChoiceStrategy: WorkerChoiceStrategy |
| 110 | ): void { |
| 111 | if (this.workerChoiceStrategy !== workerChoiceStrategy) { |
| 112 | this.workerChoiceStrategy = workerChoiceStrategy |
| 113 | } |
| 114 | this.workerChoiceStrategies.get(this.workerChoiceStrategy)?.reset() |
| 115 | } |
| 116 | |
| 117 | /** |
| 118 | * Updates the worker node key in the worker choice strategy internals in the context. |
| 119 | * |
| 120 | * @returns `true` if the update is successful, `false` otherwise. |
| 121 | */ |
| 122 | public update (workerNodeKey: number): boolean { |
| 123 | return ( |
| 124 | this.workerChoiceStrategies.get( |
| 125 | this.workerChoiceStrategy |
| 126 | ) as IWorkerChoiceStrategy |
| 127 | ).update(workerNodeKey) |
| 128 | } |
| 129 | |
| 130 | /** |
| 131 | * Executes the worker choice strategy algorithm in the context. |
| 132 | * |
| 133 | * @returns The key of the worker node. |
| 134 | * @throws {@link @node/api/errors.html#class-error} If the worker node key is null or undefined. |
| 135 | */ |
| 136 | public execute (): number { |
| 137 | const workerNodeKey = ( |
| 138 | this.workerChoiceStrategies.get( |
| 139 | this.workerChoiceStrategy |
| 140 | ) as IWorkerChoiceStrategy |
| 141 | ).choose() |
| 142 | if (workerNodeKey == null) { |
| 143 | throw new Error('Worker node key chosen is null or undefined') |
| 144 | } |
| 145 | return workerNodeKey |
| 146 | } |
| 147 | |
| 148 | /** |
| 149 | * Removes the worker node key from the worker choice strategy in the context. |
| 150 | * |
| 151 | * @param workerNodeKey - The key of the worker node. |
| 152 | * @returns `true` if the removal is successful, `false` otherwise. |
| 153 | */ |
| 154 | public remove (workerNodeKey: number): boolean { |
| 155 | return ( |
| 156 | this.workerChoiceStrategies.get( |
| 157 | this.workerChoiceStrategy |
| 158 | ) as IWorkerChoiceStrategy |
| 159 | ).remove(workerNodeKey) |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | * Sets the worker choice strategies in the context options. |
| 164 | * |
| 165 | * @param opts - The worker choice strategy options. |
| 166 | */ |
| 167 | public setOptions (opts: WorkerChoiceStrategyOptions): void { |
| 168 | this.workerChoiceStrategies.forEach(workerChoiceStrategy => { |
| 169 | workerChoiceStrategy.setOptions(opts) |
| 170 | }) |
| 171 | } |
| 172 | } |