-import { DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS } from '../../utils'
-import type { IPool } from '../pool'
-import type { IWorker } from '../worker'
-import { FairShareWorkerChoiceStrategy } from './fair-share-worker-choice-strategy'
-import { LessBusyWorkerChoiceStrategy } from './less-busy-worker-choice-strategy'
-import { LessUsedWorkerChoiceStrategy } from './less-used-worker-choice-strategy'
-import { RoundRobinWorkerChoiceStrategy } from './round-robin-worker-choice-strategy'
+import type { IPool } from '../pool.js'
+import type { IWorker } from '../worker.js'
+import { getWorkerChoiceStrategyRetries } from '../../utils.js'
+import { FairShareWorkerChoiceStrategy } from './fair-share-worker-choice-strategy.js'
+import { InterleavedWeightedRoundRobinWorkerChoiceStrategy } from './interleaved-weighted-round-robin-worker-choice-strategy.js'
+import { LeastBusyWorkerChoiceStrategy } from './least-busy-worker-choice-strategy.js'
+import { LeastUsedWorkerChoiceStrategy } from './least-used-worker-choice-strategy.js'
+import { LeastEluWorkerChoiceStrategy } from './least-elu-worker-choice-strategy.js'
+import { RoundRobinWorkerChoiceStrategy } from './round-robin-worker-choice-strategy.js'
import type {
IWorkerChoiceStrategy,
- RequiredStatistics,
+ StrategyPolicy,
+ TaskStatisticsRequirements,
WorkerChoiceStrategy,
WorkerChoiceStrategyOptions
-} from './selection-strategies-types'
-import { WorkerChoiceStrategies } from './selection-strategies-types'
-import { WeightedRoundRobinWorkerChoiceStrategy } from './weighted-round-robin-worker-choice-strategy'
+} from './selection-strategies-types.js'
+import { WorkerChoiceStrategies } from './selection-strategies-types.js'
+import { WeightedRoundRobinWorkerChoiceStrategy } from './weighted-round-robin-worker-choice-strategy.js'
/**
* The worker choice strategy context.
*
* @typeParam Worker - Type of worker.
- * @typeParam Data - Type of data sent to the worker. This can only be serializable data.
- * @typeParam Response - Type of execution response. This can only be serializable data.
+ * @typeParam Data - Type of data sent to the worker. This can only be structured-cloneable data.
+ * @typeParam Response - Type of execution response. This can only be structured-cloneable data.
*/
export class WorkerChoiceStrategyContext<
Worker extends IWorker,
Data = unknown,
Response = unknown
> {
+ /**
+ * The worker choice strategy instances registered in the context.
+ */
private readonly workerChoiceStrategies: Map<
WorkerChoiceStrategy,
IWorkerChoiceStrategy
>
+ /**
+ * The number of worker choice strategy execution retries.
+ */
+ private readonly retries: number
+
/**
* Worker choice strategy context constructor.
*
public constructor (
pool: IPool<Worker, Data, Response>,
private workerChoiceStrategy: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN,
- opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
+ opts?: WorkerChoiceStrategyOptions
) {
this.execute = this.execute.bind(this)
this.workerChoiceStrategies = new Map<
)
],
[
- WorkerChoiceStrategies.LESS_USED,
- new (LessUsedWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ WorkerChoiceStrategies.LEAST_USED,
+ new (LeastUsedWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
pool,
opts
)
],
[
- WorkerChoiceStrategies.LESS_BUSY,
- new (LessBusyWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ WorkerChoiceStrategies.LEAST_BUSY,
+ new (LeastBusyWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.LEAST_ELU,
+ new (LeastEluWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
pool,
opts
)
Data,
Response
>(pool, opts)
+ ],
+ [
+ WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN,
+ new (InterleavedWeightedRoundRobinWorkerChoiceStrategy.bind(this))<
+ Worker,
+ Data,
+ Response
+ >(pool, opts)
]
])
+ this.retries = getWorkerChoiceStrategyRetries(pool, opts)
+ }
+
+ /**
+ * Gets the strategy policy in the context.
+ *
+ * @returns The strategy policy.
+ */
+ public getStrategyPolicy (): StrategyPolicy {
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ return this.workerChoiceStrategies.get(this.workerChoiceStrategy)!
+ .strategyPolicy
}
/**
- * Gets the worker choice strategy in the context required statistics.
+ * Gets the worker choice strategy in the context task statistics requirements.
*
- * @returns The required statistics.
+ * @returns The task statistics requirements.
*/
- public getRequiredStatistics (): RequiredStatistics {
- return (
- this.workerChoiceStrategies.get(
- this.workerChoiceStrategy
- ) as IWorkerChoiceStrategy
- ).requiredStatistics
+ public getTaskStatisticsRequirements (): TaskStatisticsRequirements {
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ return this.workerChoiceStrategies.get(this.workerChoiceStrategy)!
+ .taskStatisticsRequirements
}
/**
}
/**
- * Updates the worker choice strategy internals in the context.
+ * Updates the worker node key in the worker choice strategy in the context internals.
*
* @returns `true` if the update is successful, `false` otherwise.
*/
public update (workerNodeKey: number): boolean {
- return (
- this.workerChoiceStrategies.get(
- this.workerChoiceStrategy
- ) as IWorkerChoiceStrategy
- ).update(workerNodeKey)
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ return this.workerChoiceStrategies
+ .get(this.workerChoiceStrategy)!
+ .update(workerNodeKey)
}
/**
- * Executes the worker choice strategy algorithm in the context.
+ * Executes the worker choice strategy in the context algorithm.
*
* @returns The key of the worker node.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If after computed retries the worker node key is null or undefined.
*/
public execute (): number {
- return (
- this.workerChoiceStrategies.get(
- this.workerChoiceStrategy
- ) as IWorkerChoiceStrategy
- ).choose()
+ return this.executeStrategy(
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ this.workerChoiceStrategies.get(this.workerChoiceStrategy)!
+ )
}
/**
- * Removes a worker node key from the worker choice strategy in the context.
+ * Executes the given worker choice strategy.
*
- * @param workerNodeKey - The key of the worker node.
+ * @param workerChoiceStrategy - The worker choice strategy.
+ * @returns The key of the worker node.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If after computed retries the worker node key is null or undefined.
+ */
+ private executeStrategy (workerChoiceStrategy: IWorkerChoiceStrategy): number {
+ let workerNodeKey: number | undefined
+ let chooseCount = 0
+ let retriesCount = 0
+ do {
+ workerNodeKey = workerChoiceStrategy.choose()
+ if (workerNodeKey == null && chooseCount > 0) {
+ retriesCount++
+ }
+ chooseCount++
+ } while (workerNodeKey == null && retriesCount < this.retries)
+ if (workerNodeKey == null) {
+ throw new Error(
+ `Worker node key chosen is null or undefined after ${retriesCount} retries`
+ )
+ }
+ return workerNodeKey
+ }
+
+ /**
+ * Removes the worker node key from the worker choice strategy in the context.
+ *
+ * @param workerNodeKey - The worker node key.
* @returns `true` if the removal is successful, `false` otherwise.
*/
public remove (workerNodeKey: number): boolean {
- return (
- this.workerChoiceStrategies.get(
- this.workerChoiceStrategy
- ) as IWorkerChoiceStrategy
- ).remove(workerNodeKey)
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ return this.workerChoiceStrategies
+ .get(this.workerChoiceStrategy)!
+ .remove(workerNodeKey)
}
/**
*
* @param opts - The worker choice strategy options.
*/
- public setOptions (opts: WorkerChoiceStrategyOptions): void {
- this.workerChoiceStrategies.forEach(workerChoiceStrategy => {
+ public setOptions (opts: WorkerChoiceStrategyOptions | undefined): void {
+ for (const workerChoiceStrategy of this.workerChoiceStrategies.values()) {
workerChoiceStrategy.setOptions(opts)
- })
+ }
}
}