-import type { AbstractPoolWorker } from '../abstract-pool-worker'
-import type { IPoolInternal } from '../pool-internal'
-import { PoolType } from '../pool-internal'
-import { DynamicPoolWorkerChoiceStrategy } from './dynamic-pool-worker-choice-strategy'
+import type { IPool } from '../pool.js'
+import { getWorkerChoiceStrategyRetries } from '../utils.js'
+import type { IWorker } from '../worker.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 { LeastEluWorkerChoiceStrategy } from './least-elu-worker-choice-strategy.js'
+import { LeastUsedWorkerChoiceStrategy } from './least-used-worker-choice-strategy.js'
+import { RoundRobinWorkerChoiceStrategy } from './round-robin-worker-choice-strategy.js'
import type {
IWorkerChoiceStrategy,
- WorkerChoiceStrategy
-} from './selection-strategies-types'
-import { WorkerChoiceStrategies } from './selection-strategies-types'
-import { SelectionStrategiesUtils } from './selection-strategies-utils'
+ StrategyPolicy,
+ TaskStatisticsRequirements,
+ WorkerChoiceStrategy,
+ WorkerChoiceStrategyOptions
+} 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.
*
- * @template Worker Type of worker.
- * @template Data Type of data sent to the worker. This can only be serializable data.
- * @template Response Type of response of execution. This can only be serializable data.
+ * @typeParam Worker - Type of worker.
+ * @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 AbstractPoolWorker,
- Data,
- Response
+ Worker extends IWorker,
+ Data = unknown,
+ Response = unknown
> {
- private workerChoiceStrategy!: IWorkerChoiceStrategy<Worker>
+ /**
+ * The number of worker choice strategy execution retries.
+ */
+ public retriesCount: number
+
+ /**
+ * The worker choice strategy instances registered in the context.
+ */
+ private readonly workerChoiceStrategies: Map<
+ WorkerChoiceStrategy,
+ IWorkerChoiceStrategy
+ >
+
+ /**
+ * The maximum number of worker choice strategy execution retries.
+ */
+ private readonly retries: number
/**
* Worker choice strategy context constructor.
*
- * @param pool The pool instance.
- * @param createDynamicallyWorkerCallback The worker creation callback for dynamic pool.
- * @param workerChoiceStrategy The worker choice strategy.
+ * @param pool - The pool instance.
+ * @param workerChoiceStrategy - The worker choice strategy.
+ * @param opts - The worker choice strategy options.
*/
public constructor (
- private readonly pool: IPoolInternal<Worker, Data, Response>,
- private createDynamicallyWorkerCallback: () => Worker,
- workerChoiceStrategy: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
+ pool: IPool<Worker, Data, Response>,
+ private workerChoiceStrategy: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN,
+ opts?: WorkerChoiceStrategyOptions
) {
- this.setWorkerChoiceStrategy(workerChoiceStrategy)
+ this.execute = this.execute.bind(this)
+ this.workerChoiceStrategies = new Map<
+ WorkerChoiceStrategy,
+ IWorkerChoiceStrategy
+ >([
+ [
+ WorkerChoiceStrategies.ROUND_ROBIN,
+ new (RoundRobinWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.LEAST_USED,
+ new (LeastUsedWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.LEAST_BUSY,
+ new (LeastBusyWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.LEAST_ELU,
+ new (LeastEluWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.FAIR_SHARE,
+ new (FairShareWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
+ pool,
+ opts
+ )
+ ],
+ [
+ WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN,
+ new (WeightedRoundRobinWorkerChoiceStrategy.bind(this))<
+ Worker,
+ Data,
+ Response
+ >(pool, opts)
+ ],
+ [
+ WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN,
+ new (InterleavedWeightedRoundRobinWorkerChoiceStrategy.bind(this))<
+ Worker,
+ Data,
+ Response
+ >(pool, opts)
+ ]
+ ])
+ this.retriesCount = 0
+ this.retries = getWorkerChoiceStrategyRetries(pool, opts)
}
/**
- * Gets the worker choice strategy instance specific to the pool type.
+ * Gets the strategy policy in the context.
*
- * @param workerChoiceStrategy The worker choice strategy.
- * @returns The worker choice strategy instance for the pool type.
+ * @returns The strategy policy.
*/
- private getPoolWorkerChoiceStrategy (
- workerChoiceStrategy: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
- ): IWorkerChoiceStrategy<Worker> {
- if (this.pool.type === PoolType.DYNAMIC) {
- return new DynamicPoolWorkerChoiceStrategy(
- this.pool,
- this.createDynamicallyWorkerCallback,
- workerChoiceStrategy
- )
- }
- return SelectionStrategiesUtils.getWorkerChoiceStrategy(
- this.pool,
- workerChoiceStrategy
- )
+ 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 used in the context.
+ * Gets the worker choice strategy in the context task statistics requirements.
*
- * @returns The worker choice strategy.
+ * @returns The task statistics requirements.
*/
- public getWorkerChoiceStrategy (): IWorkerChoiceStrategy<Worker> {
- return this.workerChoiceStrategy
+ public getTaskStatisticsRequirements (): TaskStatisticsRequirements {
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ return this.workerChoiceStrategies.get(this.workerChoiceStrategy)!
+ .taskStatisticsRequirements
}
/**
* Sets the worker choice strategy to use in the context.
*
- * @param workerChoiceStrategy The worker choice strategy to set.
+ * @param workerChoiceStrategy - The worker choice strategy to set.
*/
public setWorkerChoiceStrategy (
workerChoiceStrategy: WorkerChoiceStrategy
): void {
- this.workerChoiceStrategy = this.getPoolWorkerChoiceStrategy(
- workerChoiceStrategy
+ 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 {
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ return this.workerChoiceStrategies
+ .get(this.workerChoiceStrategy)!
+ .update(workerNodeKey)
+ }
+
+ /**
+ * 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.executeStrategy(
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ this.workerChoiceStrategies.get(this.workerChoiceStrategy)!
)
}
/**
- * Chooses a worker with the underlying selection strategy.
+ * Executes the given worker choice strategy.
*
- * @returns The chosen one.
+ * @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.
*/
- public execute (): Worker {
- return this.workerChoiceStrategy.choose()
+ 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
+ ++this.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 {
+ // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+ return this.workerChoiceStrategies
+ .get(this.workerChoiceStrategy)!
+ .remove(workerNodeKey)
+ }
+
+ /**
+ * Sets the worker choice strategies in the context options.
+ *
+ * @param opts - The worker choice strategy options.
+ */
+ public setOptions (opts: WorkerChoiceStrategyOptions | undefined): void {
+ for (const workerChoiceStrategy of this.workerChoiceStrategies.values()) {
+ workerChoiceStrategy.setOptions(opts)
+ }
}
}