1 import { buildInternalWorkerChoiceStrategyOptions
} 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 { InterleavedWeightedRoundRobinWorkerChoiceStrategy
} from
'./interleaved-weighted-round-robin-worker-choice-strategy'
6 import { LeastBusyWorkerChoiceStrategy
} from
'./least-busy-worker-choice-strategy'
7 import { LeastUsedWorkerChoiceStrategy
} from
'./least-used-worker-choice-strategy'
8 import { LeastEluWorkerChoiceStrategy
} from
'./least-elu-worker-choice-strategy'
9 import { RoundRobinWorkerChoiceStrategy
} from
'./round-robin-worker-choice-strategy'
11 IWorkerChoiceStrategy
,
12 InternalWorkerChoiceStrategyOptions
,
14 TaskStatisticsRequirements
,
16 } from
'./selection-strategies-types'
17 import { WorkerChoiceStrategies
} from
'./selection-strategies-types'
18 import { WeightedRoundRobinWorkerChoiceStrategy
} from
'./weighted-round-robin-worker-choice-strategy'
21 * The worker choice strategy context.
23 * @typeParam Worker - Type of worker.
24 * @typeParam Data - Type of data sent to the worker. This can only be structured-cloneable data.
25 * @typeParam Response - Type of execution response. This can only be structured-cloneable data.
27 export class WorkerChoiceStrategyContext
<
28 Worker
extends IWorker
,
32 private readonly workerChoiceStrategies
: Map
<
38 * Worker choice strategy context constructor.
40 * @param pool - The pool instance.
41 * @param workerChoiceStrategy - The worker choice strategy.
42 * @param opts - The worker choice strategy options.
45 pool
: IPool
<Worker
, Data
, Response
>,
46 private workerChoiceStrategy
: WorkerChoiceStrategy
= WorkerChoiceStrategies
.ROUND_ROBIN
,
47 private opts
?: InternalWorkerChoiceStrategyOptions
49 this.opts
= buildInternalWorkerChoiceStrategyOptions(
53 this.execute
= this.execute
.bind(this)
54 this.workerChoiceStrategies
= new Map
<
59 WorkerChoiceStrategies
.ROUND_ROBIN
,
60 new (RoundRobinWorkerChoiceStrategy
.bind(this))<Worker
, Data
, Response
>(
66 WorkerChoiceStrategies
.LEAST_USED
,
67 new (LeastUsedWorkerChoiceStrategy
.bind(this))<Worker
, Data
, Response
>(
73 WorkerChoiceStrategies
.LEAST_BUSY
,
74 new (LeastBusyWorkerChoiceStrategy
.bind(this))<Worker
, Data
, Response
>(
80 WorkerChoiceStrategies
.LEAST_ELU
,
81 new (LeastEluWorkerChoiceStrategy
.bind(this))<Worker
, Data
, Response
>(
87 WorkerChoiceStrategies
.FAIR_SHARE
,
88 new (FairShareWorkerChoiceStrategy
.bind(this))<Worker
, Data
, Response
>(
94 WorkerChoiceStrategies
.WEIGHTED_ROUND_ROBIN
,
95 new (WeightedRoundRobinWorkerChoiceStrategy
.bind(this))<
102 WorkerChoiceStrategies
.INTERLEAVED_WEIGHTED_ROUND_ROBIN
,
103 new (InterleavedWeightedRoundRobinWorkerChoiceStrategy
.bind(this))<
113 * Gets the strategy policy in the context.
115 * @returns The strategy policy.
117 public getStrategyPolicy (): StrategyPolicy
{
119 this.workerChoiceStrategies
.get(
120 this.workerChoiceStrategy
121 ) as IWorkerChoiceStrategy
126 * Gets the worker choice strategy in the context task statistics requirements.
128 * @returns The task statistics requirements.
130 public getTaskStatisticsRequirements (): TaskStatisticsRequirements
{
132 this.workerChoiceStrategies
.get(
133 this.workerChoiceStrategy
134 ) as IWorkerChoiceStrategy
135 ).taskStatisticsRequirements
139 * Sets the worker choice strategy to use in the context.
141 * @param workerChoiceStrategy - The worker choice strategy to set.
143 public setWorkerChoiceStrategy (
144 workerChoiceStrategy
: WorkerChoiceStrategy
146 if (this.workerChoiceStrategy
!== workerChoiceStrategy
) {
147 this.workerChoiceStrategy
= workerChoiceStrategy
149 this.workerChoiceStrategies
.get(this.workerChoiceStrategy
)?.reset()
153 * Updates the worker node key in the worker choice strategy in the context internals.
155 * @returns `true` if the update is successful, `false` otherwise.
157 public update (workerNodeKey
: number): boolean {
159 this.workerChoiceStrategies
.get(
160 this.workerChoiceStrategy
161 ) as IWorkerChoiceStrategy
162 ).update(workerNodeKey
)
166 * Executes the worker choice strategy in the context algorithm.
168 * @returns The key of the worker node.
169 * @throws {@link https://nodejs.org/api/errors.html#class-error} If after configured retries the worker node key is null or undefined.
171 public execute (): number {
172 const workerChoiceStrategy
= this.workerChoiceStrategies
.get(
173 this.workerChoiceStrategy
174 ) as IWorkerChoiceStrategy
175 if (!workerChoiceStrategy
.hasPoolWorkerNodesReady()) {
176 return this.execute()
178 return this.executeStrategy(workerChoiceStrategy
)
182 * Executes the given worker choice strategy.
184 * @param workerChoiceStrategy - The worker choice strategy.
185 * @returns The key of the worker node.
186 * @throws {@link https://nodejs.org/api/errors.html#class-error} If after configured retries the worker node key is null or undefined.
188 private executeStrategy (workerChoiceStrategy
: IWorkerChoiceStrategy
): number {
189 let workerNodeKey
: number | undefined
193 workerNodeKey
= workerChoiceStrategy
.choose()
194 if (workerNodeKey
== null && chooseCount
> 0) {
199 workerNodeKey
== null &&
200 retriesCount
< (this.opts
?.retries
as number)
202 if (workerNodeKey
== null) {
204 `Worker node key chosen is null or undefined after ${retriesCount} retries`
211 * Removes the worker node key from the worker choice strategy in the context.
213 * @param workerNodeKey - The worker node key.
214 * @returns `true` if the removal is successful, `false` otherwise.
216 public remove (workerNodeKey
: number): boolean {
218 this.workerChoiceStrategies
.get(
219 this.workerChoiceStrategy
220 ) as IWorkerChoiceStrategy
221 ).remove(workerNodeKey
)
225 * Sets the worker choice strategies in the context options.
227 * @param pool - The pool instance.
228 * @param opts - The worker choice strategy options.
231 pool
: IPool
<Worker
, Data
, Response
>,
232 opts
?: InternalWorkerChoiceStrategyOptions
234 this.opts
= buildInternalWorkerChoiceStrategyOptions(
238 for (const workerChoiceStrategy
of this.workerChoiceStrategies
.values()) {
239 workerChoiceStrategy
.setOptions(this.opts
)