import crypto from 'node:crypto'
import type { MessageValue, PromiseResponseWrapper } from '../utility-types'
-import { EMPTY_FUNCTION, median } from '../utils'
+import {
+ DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS,
+ EMPTY_FUNCTION,
+ median
+} from '../utils'
import { KillBehaviors, isKillBehavior } from '../worker/worker-options'
-import { PoolEvents, type PoolOptions } from './pool'
+import {
+ PoolEvents,
+ type IPool,
+ type PoolOptions,
+ type TasksQueueOptions,
+ PoolType
+} from './pool'
import { PoolEmitter } from './pool'
-import type { IPoolInternal } from './pool-internal'
-import { PoolType } from './pool-internal'
import type { IWorker, Task, TasksUsage, WorkerNode } from './worker'
import {
WorkerChoiceStrategies,
Worker extends IWorker,
Data = unknown,
Response = unknown
-> implements IPoolInternal<Worker, Data, Response> {
+> implements IPool<Worker, Data, Response> {
/** @inheritDoc */
public readonly workerNodes: Array<WorkerNode<Worker, Data>> = []
public readonly emitter?: PoolEmitter
/**
- * The promise response map.
+ * The execution response promise map.
*
* - `key`: The message id of each submitted task.
- * - `value`: An object that contains the worker, the promise resolve and reject callbacks.
+ * - `value`: An object that contains the worker, the execution response promise resolve and reject callbacks.
*
- * When we receive a message from the worker we get a map entry with the promise resolve/reject bound to the message.
+ * When we receive a message from the worker, we get a map entry with the promise resolve/reject bound to the message id.
*/
protected promiseResponseMap: Map<
string,
this.checkFilePath(this.filePath)
this.checkPoolOptions(this.opts)
- this.chooseWorker.bind(this)
- this.internalExecute.bind(this)
- this.checkAndEmitFull.bind(this)
- this.checkAndEmitBusy.bind(this)
- this.sendToWorker.bind(this)
+ this.chooseWorkerNode.bind(this)
+ this.executeTask.bind(this)
+ this.enqueueTask.bind(this)
+ this.checkAndEmitEvents.bind(this)
this.setupHook()
Worker,
Data,
Response
- >(this, this.opts.workerChoiceStrategy)
+ >(
+ this,
+ this.opts.workerChoiceStrategy,
+ this.opts.workerChoiceStrategyOptions
+ )
}
private checkFilePath (filePath: string): void {
this.opts.workerChoiceStrategy =
opts.workerChoiceStrategy ?? WorkerChoiceStrategies.ROUND_ROBIN
this.checkValidWorkerChoiceStrategy(this.opts.workerChoiceStrategy)
+ this.opts.workerChoiceStrategyOptions =
+ opts.workerChoiceStrategyOptions ?? DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
this.opts.enableEvents = opts.enableEvents ?? true
+ this.opts.enableTasksQueue = opts.enableTasksQueue ?? false
+ if (this.opts.enableTasksQueue) {
+ if ((opts.tasksQueueOptions?.concurrency as number) <= 0) {
+ throw new Error(
+ `Invalid worker tasks concurrency '${
+ (opts.tasksQueueOptions as TasksQueueOptions).concurrency as number
+ }'`
+ )
+ }
+ this.opts.tasksQueueOptions = {
+ concurrency: opts.tasksQueueOptions?.concurrency ?? 1
+ }
+ }
}
private checkValidWorkerChoiceStrategy (
public abstract get type (): PoolType
/**
- * Number of tasks concurrently running in the pool.
+ * Number of tasks running in the pool.
*/
private get numberOfRunningTasks (): number {
- return this.promiseResponseMap.size
+ return this.workerNodes.reduce(
+ (accumulator, workerNode) => accumulator + workerNode.tasksUsage.running,
+ 0
+ )
+ }
+
+ /**
+ * Number of tasks queued in the pool.
+ */
+ private get numberOfQueuedTasks (): number {
+ if (this.opts.enableTasksQueue === false) {
+ return 0
+ }
+ return this.workerNodes.reduce(
+ (accumulator, workerNode) => accumulator + workerNode.tasksQueue.length,
+ 0
+ )
}
/**
): void {
this.checkValidWorkerChoiceStrategy(workerChoiceStrategy)
this.opts.workerChoiceStrategy = workerChoiceStrategy
- for (const [index, workerNode] of this.workerNodes.entries()) {
- this.setWorkerNode(
- index,
- workerNode.worker,
- {
- run: 0,
- running: 0,
- runTime: 0,
- runTimeHistory: new CircularArray(),
- avgRunTime: 0,
- medRunTime: 0,
- error: 0
- },
- workerNode.tasksQueue
- )
+ for (const workerNode of this.workerNodes) {
+ this.setWorkerNodeTasksUsage(workerNode, {
+ run: 0,
+ running: 0,
+ runTime: 0,
+ runTimeHistory: new CircularArray(),
+ avgRunTime: 0,
+ medRunTime: 0,
+ error: 0
+ })
}
this.workerChoiceStrategyContext.setWorkerChoiceStrategy(
workerChoiceStrategy
)
}
- /** @inheritDoc */
- public abstract get full (): boolean
+ /**
+ * Whether the pool is full or not.
+ *
+ * The pool filling boolean status.
+ */
+ protected abstract get full (): boolean
- /** @inheritDoc */
- public abstract get busy (): boolean
+ /**
+ * Whether the pool is busy or not.
+ *
+ * The pool busyness boolean status.
+ */
+ protected abstract get busy (): boolean
protected internalBusy (): boolean {
- return (
- this.numberOfRunningTasks >= this.numberOfWorkers &&
- this.findFreeWorkerNodeKey() === -1
- )
+ return this.findFreeWorkerNodeKey() === -1
}
/** @inheritDoc */
/** @inheritDoc */
public async execute (data: Data): Promise<Response> {
- const [workerNodeKey, worker] = this.chooseWorker()
- const messageId = crypto.randomUUID()
- const res = this.internalExecute(workerNodeKey, worker, messageId)
- this.checkAndEmitFull()
- this.checkAndEmitBusy()
- this.sendToWorker(worker, {
+ const [workerNodeKey, workerNode] = this.chooseWorkerNode()
+ const submittedTask: Task<Data> = {
// eslint-disable-next-line @typescript-eslint/consistent-type-assertions
data: data ?? ({} as Data),
- id: messageId
+ id: crypto.randomUUID()
+ }
+ const res = new Promise<Response>((resolve, reject) => {
+ this.promiseResponseMap.set(submittedTask.id, {
+ resolve,
+ reject,
+ worker: workerNode.worker
+ })
})
+ if (
+ this.opts.enableTasksQueue === true &&
+ (this.busy ||
+ this.workerNodes[workerNodeKey].tasksUsage.running >=
+ ((this.opts.tasksQueueOptions as TasksQueueOptions)
+ .concurrency as number))
+ ) {
+ this.enqueueTask(workerNodeKey, submittedTask)
+ } else {
+ this.executeTask(workerNodeKey, submittedTask)
+ }
+ this.checkAndEmitEvents()
// eslint-disable-next-line @typescript-eslint/return-await
return res
}
/** @inheritDoc */
public async destroy (): Promise<void> {
await Promise.all(
- this.workerNodes.map(async workerNode => {
+ this.workerNodes.map(async (workerNode, workerNodeKey) => {
+ this.flushTasksQueue(workerNodeKey)
await this.destroyWorker(workerNode.worker)
})
)
protected abstract destroyWorker (worker: Worker): void | Promise<void>
/**
- * Setup hook to run code before worker node are created in the abstract constructor.
+ * Setup hook to execute code before worker node are created in the abstract constructor.
* Can be overridden
*
* @virtual
protected abstract isMain (): boolean
/**
- * Hook executed before the worker task promise resolution.
+ * Hook executed before the worker task execution.
* Can be overridden.
*
* @param workerNodeKey - The worker node key.
*/
- protected beforePromiseResponseHook (workerNodeKey: number): void {
+ protected beforeTaskExecutionHook (workerNodeKey: number): void {
++this.workerNodes[workerNodeKey].tasksUsage.running
}
/**
- * Hook executed after the worker task promise resolution.
+ * Hook executed after the worker task execution.
* Can be overridden.
*
* @param worker - The worker.
* @param message - The received message.
*/
- protected afterPromiseResponseHook (
+ protected afterTaskExecutionHook (
worker: Worker,
message: MessageValue<Response>
): void {
*
* The default uses a round robin algorithm to distribute the load.
*
- * @returns [worker node key, worker].
+ * @returns [worker node key, worker node].
*/
- protected chooseWorker (): [number, Worker] {
+ protected chooseWorkerNode (): [number, WorkerNode<Worker, Data>] {
let workerNodeKey: number
- if (
- this.type === PoolType.DYNAMIC &&
- !this.full &&
- this.findFreeWorkerNodeKey() === -1
- ) {
- const createdWorker = this.createAndSetupWorker()
- this.registerWorkerMessageListener(createdWorker, message => {
+ if (this.type === PoolType.DYNAMIC && !this.full && this.internalBusy()) {
+ const workerCreated = this.createAndSetupWorker()
+ this.registerWorkerMessageListener(workerCreated, message => {
if (
isKillBehavior(KillBehaviors.HARD, message.kill) ||
(message.kill != null &&
- this.getWorkerTasksUsage(createdWorker)?.running === 0)
+ this.getWorkerTasksUsage(workerCreated)?.running === 0)
) {
- // Kill message received from the worker, means that no new tasks are submitted to that worker for a while ( > maxInactiveTime)
- void this.destroyWorker(createdWorker)
+ // Kill message received from the worker: no new tasks are submitted to that worker for a while ( > maxInactiveTime)
+ this.flushTasksQueueByWorker(workerCreated)
+ void this.destroyWorker(workerCreated)
}
})
- workerNodeKey = this.getWorkerNodeKey(createdWorker)
+ workerNodeKey = this.getWorkerNodeKey(workerCreated)
} else {
workerNodeKey = this.workerChoiceStrategyContext.execute()
}
- return [workerNodeKey, this.workerNodes[workerNodeKey].worker]
+ return [workerNodeKey, this.workerNodes[workerNodeKey]]
}
/**
}
/**
- * This function is the listener registered for each worker.
+ * This function is the listener registered for each worker message.
*
* @returns The listener function to execute when a message is received from a worker.
*/
protected workerListener (): (message: MessageValue<Response>) => void {
return message => {
if (message.id != null) {
- // Task response received
+ // Task execution response received
const promiseResponse = this.promiseResponseMap.get(message.id)
if (promiseResponse != null) {
if (message.error != null) {
} else {
promiseResponse.resolve(message.data as Response)
}
- this.afterPromiseResponseHook(promiseResponse.worker, message)
+ this.afterTaskExecutionHook(promiseResponse.worker, message)
this.promiseResponseMap.delete(message.id)
+ const workerNodeKey = this.getWorkerNodeKey(promiseResponse.worker)
+ if (
+ this.opts.enableTasksQueue === true &&
+ this.tasksQueueSize(workerNodeKey) > 0
+ ) {
+ this.executeTask(
+ workerNodeKey,
+ this.dequeueTask(workerNodeKey) as Task<Data>
+ )
+ }
}
}
}
}
- private async internalExecute (
- workerNodeKey: number,
- worker: Worker,
- messageId: string
- ): Promise<Response> {
- this.beforePromiseResponseHook(workerNodeKey)
- return await new Promise<Response>((resolve, reject) => {
- this.promiseResponseMap.set(messageId, { resolve, reject, worker })
- })
- }
-
- private checkAndEmitBusy (): void {
- if (this.opts.enableEvents === true && this.busy) {
- this.emitter?.emit(PoolEvents.busy)
+ private checkAndEmitEvents (): void {
+ if (this.opts.enableEvents === true) {
+ if (this.busy) {
+ this.emitter?.emit(PoolEvents.busy)
+ }
+ if (this.type === PoolType.DYNAMIC && this.full) {
+ this.emitter?.emit(PoolEvents.full)
+ }
}
}
- private checkAndEmitFull (): void {
- if (
- this.type === PoolType.DYNAMIC &&
- this.opts.enableEvents === true &&
- this.full
- ) {
- this.emitter?.emit(PoolEvents.full)
- }
+ /**
+ * Sets the given worker node its tasks usage in the pool.
+ *
+ * @param workerNode - The worker node.
+ * @param tasksUsage - The worker node tasks usage.
+ */
+ private setWorkerNodeTasksUsage (
+ workerNode: WorkerNode<Worker, Data>,
+ tasksUsage: TasksUsage
+ ): void {
+ workerNode.tasksUsage = tasksUsage
}
/**
*
* @param worker - The worker.
*/
- protected removeWorkerNode (worker: Worker): void {
+ private removeWorkerNode (worker: Worker): void {
const workerNodeKey = this.getWorkerNodeKey(worker)
this.workerNodes.splice(workerNodeKey, 1)
this.workerChoiceStrategyContext.remove(workerNodeKey)
}
+
+ private executeTask (workerNodeKey: number, task: Task<Data>): void {
+ this.beforeTaskExecutionHook(workerNodeKey)
+ this.sendToWorker(this.workerNodes[workerNodeKey].worker, task)
+ }
+
+ private enqueueTask (workerNodeKey: number, task: Task<Data>): number {
+ return this.workerNodes[workerNodeKey].tasksQueue.push(task)
+ }
+
+ private dequeueTask (workerNodeKey: number): Task<Data> | undefined {
+ return this.workerNodes[workerNodeKey].tasksQueue.shift()
+ }
+
+ private tasksQueueSize (workerNodeKey: number): number {
+ return this.workerNodes[workerNodeKey].tasksQueue.length
+ }
+
+ private flushTasksQueue (workerNodeKey: number): void {
+ if (this.tasksQueueSize(workerNodeKey) > 0) {
+ for (const task of this.workerNodes[workerNodeKey].tasksQueue) {
+ this.executeTask(workerNodeKey, task)
+ }
+ }
+ }
+
+ private flushTasksQueueByWorker (worker: Worker): void {
+ const workerNodeKey = this.getWorkerNodeKey(worker)
+ this.flushTasksQueue(workerNodeKey)
+ }
}