-import type { IPoolInternal } from '../pool-internal'
-import type { IPoolWorker } from '../pool-worker'
+import { buildInternalWorkerChoiceStrategyOptions } from '../../utils'
+import type { IPool } from '../pool'
+import type { IWorker } from '../worker'
+import { FairShareWorkerChoiceStrategy } from './fair-share-worker-choice-strategy'
+import { InterleavedWeightedRoundRobinWorkerChoiceStrategy } from './interleaved-weighted-round-robin-worker-choice-strategy'
+import { LeastBusyWorkerChoiceStrategy } from './least-busy-worker-choice-strategy'
+import { LeastUsedWorkerChoiceStrategy } from './least-used-worker-choice-strategy'
+import { LeastEluWorkerChoiceStrategy } from './least-elu-worker-choice-strategy'
+import { RoundRobinWorkerChoiceStrategy } from './round-robin-worker-choice-strategy'
import type {
IWorkerChoiceStrategy,
- RequiredStatistics,
+ InternalWorkerChoiceStrategyOptions,
+ StrategyPolicy,
+ TaskStatisticsRequirements,
WorkerChoiceStrategy
} from './selection-strategies-types'
import { WorkerChoiceStrategies } from './selection-strategies-types'
-import { getWorkerChoiceStrategy } from './selection-strategies-utils'
+import { WeightedRoundRobinWorkerChoiceStrategy } from './weighted-round-robin-worker-choice-strategy'
/**
* 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 response of execution. 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 IPoolWorker,
+ Worker extends IWorker,
Data = unknown,
Response = unknown
> {
- private workerChoiceStrategy: IWorkerChoiceStrategy<Worker, Data, Response>
+ private readonly workerChoiceStrategies: Map<
+ WorkerChoiceStrategy,
+ IWorkerChoiceStrategy
+ >
/**
* Worker choice strategy context constructor.
*
* @param pool - The pool instance.
- * @param createWorkerCallback - The worker creation callback for dynamic pool.
* @param workerChoiceStrategy - The worker choice strategy.
+ * @param opts - The worker choice strategy options.
*/
public constructor (
- pool: IPoolInternal<Worker, Data, Response>,
- private readonly createWorkerCallback: () => number,
- private workerChoiceStrategyType: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
+ pool: IPool<Worker, Data, Response>,
+ private workerChoiceStrategy: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN,
+ private opts?: InternalWorkerChoiceStrategyOptions
) {
- this.execute.bind(this)
- this.workerChoiceStrategy = getWorkerChoiceStrategy<Worker, Data, Response>(
- pool,
- this.workerChoiceStrategyType
+ this.opts = buildInternalWorkerChoiceStrategyOptions(
+ pool.info.maxSize,
+ this.opts
)
+ this.execute = this.execute.bind(this)
+ this.workerChoiceStrategies = new Map<
+ WorkerChoiceStrategy,
+ IWorkerChoiceStrategy
+ >([
+ [
+ WorkerChoiceStrategies.ROUND_ROBIN,
+ new (RoundRobinWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ this.opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.LEAST_USED,
+ new (LeastUsedWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ this.opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.LEAST_BUSY,
+ new (LeastBusyWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ this.opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.LEAST_ELU,
+ new (LeastEluWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ this.opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.FAIR_SHARE,
+ new (FairShareWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ this.opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN,
+ new (WeightedRoundRobinWorkerChoiceStrategy.bind(this))<
+ Worker,
+ Data,
+ Response
+ >(pool, this.opts)
+ ],
+ [
+ WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN,
+ new (InterleavedWeightedRoundRobinWorkerChoiceStrategy.bind(this))<
+ Worker,
+ Data,
+ Response
+ >(pool, this.opts)
+ ]
+ ])
}
/**
- * Gets the worker choice strategy required statistics.
+ * Gets the strategy policy in the context.
*
- * @returns The required statistics.
+ * @returns The strategy policy.
*/
- public getRequiredStatistics (): RequiredStatistics {
- return this.workerChoiceStrategy.requiredStatistics
+ public getStrategyPolicy (): StrategyPolicy {
+ return (
+ this.workerChoiceStrategies.get(
+ this.workerChoiceStrategy
+ ) as IWorkerChoiceStrategy
+ ).strategyPolicy
+ }
+
+ /**
+ * Gets the worker choice strategy in the context task statistics requirements.
+ *
+ * @returns The task statistics requirements.
+ */
+ public getTaskStatisticsRequirements (): TaskStatisticsRequirements {
+ return (
+ this.workerChoiceStrategies.get(
+ this.workerChoiceStrategy
+ ) as IWorkerChoiceStrategy
+ ).taskStatisticsRequirements
}
/**
* @param workerChoiceStrategy - The worker choice strategy to set.
*/
public setWorkerChoiceStrategy (
- pool: IPoolInternal<Worker, Data, Response>,
workerChoiceStrategy: WorkerChoiceStrategy
): void {
- if (this.workerChoiceStrategyType === workerChoiceStrategy) {
- this.workerChoiceStrategy?.reset()
- } else {
- this.workerChoiceStrategyType = workerChoiceStrategy
- this.workerChoiceStrategy = getWorkerChoiceStrategy<
- Worker,
- Data,
- Response
- >(pool, this.workerChoiceStrategyType)
+ if (this.workerChoiceStrategy !== workerChoiceStrategy) {
+ this.workerChoiceStrategy = workerChoiceStrategy
}
+ this.workerChoiceStrategies.get(this.workerChoiceStrategy)?.reset()
+ }
+
+ /**
+ * 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)
}
/**
- * Chooses a worker with the worker choice strategy.
+ * Executes the worker choice strategy in the context algorithm.
*
- * @returns The key of the chosen one.
+ * @returns The key of the worker node.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If after configured retries the worker node key is null or undefined.
*/
public execute (): number {
- if (
- this.workerChoiceStrategy.isDynamicPool &&
- !this.workerChoiceStrategy.pool.full &&
- this.workerChoiceStrategy.pool.findFreeWorkerKey() === -1
- ) {
- return this.createWorkerCallback()
+ const workerChoiceStrategy = this.workerChoiceStrategies.get(
+ this.workerChoiceStrategy
+ ) as IWorkerChoiceStrategy
+ if (!workerChoiceStrategy.hasPoolWorkerNodesReady()) {
+ return this.execute()
}
- return this.workerChoiceStrategy.choose()
+ return this.executeStrategy(workerChoiceStrategy)
}
/**
- * Removes a worker in the worker choice strategy internals.
+ * Executes the given worker choice strategy.
*
- * @param workerKey - The key of the worker to remove.
+ * @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 configured 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.opts?.retries as number)
+ )
+ 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 (workerKey: number): boolean {
- return this.workerChoiceStrategy.remove(workerKey)
+ public remove (workerNodeKey: number): boolean {
+ return (
+ this.workerChoiceStrategies.get(
+ this.workerChoiceStrategy
+ ) as IWorkerChoiceStrategy
+ ).remove(workerNodeKey)
+ }
+
+ /**
+ * Sets the worker choice strategies in the context options.
+ *
+ * @param pool - The pool instance.
+ * @param opts - The worker choice strategy options.
+ */
+ public setOptions (
+ pool: IPool<Worker, Data, Response>,
+ opts?: InternalWorkerChoiceStrategyOptions
+ ): void {
+ this.opts = buildInternalWorkerChoiceStrategyOptions(
+ pool.info.maxSize,
+ opts
+ )
+ for (const workerChoiceStrategy of this.workerChoiceStrategies.values()) {
+ workerChoiceStrategy.setOptions(this.opts)
+ }
}
}