X-Git-Url: https://git.piment-noir.org/?a=blobdiff_plain;f=src%2Fpools%2Fabstract-pool.ts;h=9ac81ce56558ec76fbd66d7789b2399e910a2e69;hb=aee467366d8c393b79e7af82c6a7ab12338ee64e;hp=4a6ba72f4b7523bd2d8870dd1108c6225814ff16;hpb=85a3f8a7b3087e7240c1d307ba6dd78c05883f83;p=poolifier.git diff --git a/src/pools/abstract-pool.ts b/src/pools/abstract-pool.ts index 4a6ba72f..9ac81ce5 100644 --- a/src/pools/abstract-pool.ts +++ b/src/pools/abstract-pool.ts @@ -1,196 +1,246 @@ -import EventEmitter from 'events' -import type { MessageValue } from '../utility-types' -import type { IPool } from './pool' +import crypto from 'node:crypto' +import type { MessageValue, PromiseResponseWrapper } from '../utility-types' +import { EMPTY_FUNCTION } from '../utils' +import { KillBehaviors, isKillBehavior } from '../worker/worker-options' +import { PoolEvents, type PoolOptions } from './pool' +import { PoolEmitter } from './pool' +import type { IPoolInternal, TasksUsage, WorkerType } from './pool-internal' +import { PoolType } from './pool-internal' +import type { IPoolWorker } from './pool-worker' +import { + WorkerChoiceStrategies, + type WorkerChoiceStrategy +} from './selection-strategies/selection-strategies-types' +import { WorkerChoiceStrategyContext } from './selection-strategies/worker-choice-strategy-context' /** - * Callback invoked if the worker raised an error. - */ -export type ErrorHandler = (this: Worker, e: Error) => void - -/** - * Callback invoked when the worker has started successfully. - */ -export type OnlineHandler = (this: Worker) => void - -/** - * Callback invoked when the worker exits successfully. - */ -export type ExitHandler = (this: Worker, code: number) => void - -/** - * Basic interface that describes the minimum required implementation of listener events for a pool-worker. - */ -export interface IWorker { - /** - * Register a listener to the error event. - * - * @param event `'error'`. - * @param handler The error handler. - */ - on(event: 'error', handler: ErrorHandler): void - /** - * Register a listener to the online event. - * - * @param event `'online'`. - * @param handler The online handler. - */ - on(event: 'online', handler: OnlineHandler): void - /** - * Register a listener to the exit event. - * - * @param event `'exit'`. - * @param handler The exit handler. - */ - on(event: 'exit', handler: ExitHandler): void - /** - * Register a listener to the exit event that will only performed once. - * - * @param event `'exit'`. - * @param handler The exit handler. - */ - once(event: 'exit', handler: ExitHandler): void -} - -/** - * Options for a poolifier pool. - */ -export interface PoolOptions { - /** - * A function that will listen for error event on each worker. - */ - errorHandler?: ErrorHandler - /** - * A function that will listen for online event on each worker. - */ - onlineHandler?: OnlineHandler - /** - * A function that will listen for exit event on each worker. - */ - exitHandler?: ExitHandler - /** - * This is just to avoid non-useful warning messages. - * - * Will be used to set `maxListeners` on event emitters (workers are event emitters). - * - * @default 1000 - * @see [Node events emitter.setMaxListeners(n)](https://nodejs.org/api/events.html#events_emitter_setmaxlisteners_n) - */ - maxTasks?: number -} - -/** - * Internal poolifier pool emitter. - */ -class PoolEmitter extends EventEmitter {} - -/** - * Base class containing some shared logic for all poolifier pools. + * Base class that implements some shared logic for all poolifier pools. * - * @template Worker Type of worker which manages this pool. - * @template Data Type of data sent to the worker. - * @template Response Type of response of execution. + * @typeParam Worker - Type of worker which manages this pool. + * @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. */ export abstract class AbstractPool< - Worker extends IWorker, + Worker extends IPoolWorker, Data = unknown, Response = unknown -> implements IPool { - /** - * List of currently available workers. - */ - public readonly workers: Worker[] = [] +> implements IPoolInternal { + /** @inheritDoc */ + public readonly workers: Array> = [] - /** - * Index for the next worker. - */ - public nextWorkerIndex: number = 0 + /** @inheritDoc */ + public readonly emitter?: PoolEmitter /** - * The tasks map. + * The promise response map. * - * - `key`: The `Worker` - * - `value`: Number of tasks currently in progress on the worker. - */ - public readonly tasks: Map = new Map() - - /** - * Emitter on which events can be listened to. - * - * Events that can currently be listened to: + * - `key`: The message id of each submitted task. + * - `value`: An object that contains the worker, the promise resolve and reject callbacks. * - * - `'FullPool'` + * When we receive a message from the worker we get a map entry with the promise resolve/reject bound to the message. */ - public readonly emitter: PoolEmitter + protected promiseResponseMap: Map< + string, + PromiseResponseWrapper + > = new Map>() /** - * ID of the next message. + * Worker choice strategy context referencing a worker choice algorithm implementation. + * + * Default to a round robin algorithm. */ - protected nextMessageId: number = 0 + protected workerChoiceStrategyContext: WorkerChoiceStrategyContext< + Worker, + Data, + Response + > /** * Constructs a new poolifier pool. * - * @param numberOfWorkers Number of workers that this pool should manage. - * @param filePath Path to the worker-file. - * @param opts Options for the pool. Default: `{ maxTasks: 1000 }` + * @param numberOfWorkers - Number of workers that this pool should manage. + * @param filePath - Path to the worker-file. + * @param opts - Options for the pool. */ public constructor ( public readonly numberOfWorkers: number, public readonly filePath: string, - public readonly opts: PoolOptions = { maxTasks: 1000 } + public readonly opts: PoolOptions ) { if (!this.isMain()) { throw new Error('Cannot start a pool from a worker!') } - // TODO christopher 2021-02-07: Improve this check e.g. with a pattern or blank check - if (!this.filePath) { - throw new Error('Please specify a file with a worker implementation') - } + this.checkNumberOfWorkers(this.numberOfWorkers) + 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.setupHook() for (let i = 1; i <= this.numberOfWorkers; i++) { this.createAndSetupWorker() } - this.emitter = new PoolEmitter() + if (this.opts.enableEvents === true) { + this.emitter = new PoolEmitter() + } + this.workerChoiceStrategyContext = new WorkerChoiceStrategyContext< + Worker, + Data, + Response + >(this, this.opts.workerChoiceStrategy) + } + + private checkFilePath (filePath: string): void { + if ( + filePath == null || + (typeof filePath === 'string' && filePath.trim().length === 0) + ) { + throw new Error('Please specify a file with a worker implementation') + } + } + + private checkNumberOfWorkers (numberOfWorkers: number): void { + if (numberOfWorkers == null) { + throw new Error( + 'Cannot instantiate a pool without specifying the number of workers' + ) + } else if (!Number.isSafeInteger(numberOfWorkers)) { + throw new TypeError( + 'Cannot instantiate a pool with a non integer number of workers' + ) + } else if (numberOfWorkers < 0) { + throw new RangeError( + 'Cannot instantiate a pool with a negative number of workers' + ) + } else if (this.type === PoolType.FIXED && numberOfWorkers === 0) { + throw new Error('Cannot instantiate a fixed pool with no worker') + } } + private checkPoolOptions (opts: PoolOptions): void { + this.opts.workerChoiceStrategy = + opts.workerChoiceStrategy ?? WorkerChoiceStrategies.ROUND_ROBIN + this.checkValidWorkerChoiceStrategy(this.opts.workerChoiceStrategy) + this.opts.enableEvents = opts.enableEvents ?? true + } + + private checkValidWorkerChoiceStrategy ( + workerChoiceStrategy: WorkerChoiceStrategy + ): void { + if (!Object.values(WorkerChoiceStrategies).includes(workerChoiceStrategy)) { + throw new Error( + `Invalid worker choice strategy '${workerChoiceStrategy}'` + ) + } + } + + /** @inheritDoc */ + public abstract get type (): PoolType + /** - * Perform the task specified in the constructor with the data parameter. - * - * @param data The input for the specified task. - * @returns Promise that will be resolved when the task is successfully completed. + * Number of tasks concurrently running in the pool. */ - public execute (data: Data): Promise { - // Configure worker to handle message with the specified task - const worker = this.chooseWorker() - this.increaseWorkersTask(worker) - const messageId = ++this.nextMessageId - const res = this.internalExecute(worker, messageId) - this.sendToWorker(worker, { data: data || ({} as Data), id: messageId }) - return res + private get numberOfRunningTasks (): number { + return this.promiseResponseMap.size } /** - * Shut down every current worker in this pool. + * Gets the given worker key. + * + * @param worker - The worker. + * @returns The worker key if the worker is found in the pool, `-1` otherwise. */ + private getWorkerKey (worker: Worker): number { + return this.workers.findIndex(workerItem => workerItem.worker === worker) + } + + /** @inheritDoc */ + public setWorkerChoiceStrategy ( + workerChoiceStrategy: WorkerChoiceStrategy + ): void { + this.checkValidWorkerChoiceStrategy(workerChoiceStrategy) + this.opts.workerChoiceStrategy = workerChoiceStrategy + for (const [index, workerItem] of this.workers.entries()) { + this.setWorker(index, workerItem.worker, { + run: 0, + running: 0, + runTime: 0, + avgRunTime: 0, + error: 0 + }) + } + this.workerChoiceStrategyContext.setWorkerChoiceStrategy( + workerChoiceStrategy + ) + } + + /** @inheritDoc */ + public abstract get full (): boolean + + /** @inheritDoc */ + public abstract get busy (): boolean + + protected internalBusy (): boolean { + return ( + this.numberOfRunningTasks >= this.numberOfWorkers && + this.findFreeWorkerKey() === -1 + ) + } + + /** @inheritDoc */ + public findFreeWorkerKey (): number { + return this.workers.findIndex(workerItem => { + return workerItem.tasksUsage.running === 0 + }) + } + + /** @inheritDoc */ + public async execute (data: Data): Promise { + const [workerKey, worker] = this.chooseWorker() + const messageId = crypto.randomUUID() + const res = this.internalExecute(workerKey, worker, messageId) + this.checkAndEmitFull() + this.checkAndEmitBusy() + this.sendToWorker(worker, { + // eslint-disable-next-line @typescript-eslint/consistent-type-assertions + data: data ?? ({} as Data), + id: messageId + }) + // eslint-disable-next-line @typescript-eslint/return-await + return res + } + + /** @inheritDoc */ public async destroy (): Promise { - await Promise.all(this.workers.map(worker => this.destroyWorker(worker))) + await Promise.all( + this.workers.map(async workerItem => { + await this.destroyWorker(workerItem.worker) + }) + ) } /** - * Shut down given worker. + * Shutdowns given worker in the pool. * - * @param worker A worker within `workers`. + * @param worker - A worker within `workers`. */ protected abstract destroyWorker (worker: Worker): void | Promise /** * Setup hook that can be overridden by a Poolifier pool implementation * to run code before workers are created in the abstract constructor. + * Can be overridden + * + * @virtual */ protected setupHook (): void { - // Can be overridden + // Intentionally empty } /** @@ -199,96 +249,96 @@ export abstract class AbstractPool< protected abstract isMain (): boolean /** - * Increase the number of tasks that the given workers has done. + * Hook executed before the worker task promise resolution. + * Can be overridden. * - * @param worker Workers whose tasks are increased. + * @param workerKey - The worker key. */ - protected increaseWorkersTask (worker: Worker): void { - const numberOfTasksInProgress = this.tasks.get(worker) - if (numberOfTasksInProgress !== undefined) { - this.tasks.set(worker, numberOfTasksInProgress + 1) - } else { - throw Error('Worker could not be found in tasks map') - } + protected beforePromiseResponseHook (workerKey: number): void { + ++this.workers[workerKey].tasksUsage.running } /** - * Decrease the number of tasks that the given workers has done. + * Hook executed after the worker task promise resolution. + * Can be overridden. * - * @param worker Workers whose tasks are decreased. + * @param worker - The worker. + * @param message - The received message. */ - protected decreaseWorkersTasks (worker: Worker): void { - const numberOfTasksInProgress = this.tasks.get(worker) - if (numberOfTasksInProgress !== undefined) { - this.tasks.set(worker, numberOfTasksInProgress - 1) - } else { - throw Error('Worker could not be found in tasks map') + protected afterPromiseResponseHook ( + worker: Worker, + message: MessageValue + ): void { + const workerTasksUsage = this.getWorkerTasksUsage(worker) as TasksUsage + --workerTasksUsage.running + ++workerTasksUsage.run + if (message.error != null) { + ++workerTasksUsage.error + } + if (this.workerChoiceStrategyContext.getRequiredStatistics().runTime) { + workerTasksUsage.runTime += message.runTime ?? 0 + if ( + this.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime && + workerTasksUsage.run !== 0 + ) { + workerTasksUsage.avgRunTime = + workerTasksUsage.runTime / workerTasksUsage.run + } } } /** - * Removes the given worker from the pool. - * - * @param worker Worker that will be removed. - */ - protected removeWorker (worker: Worker): void { - // Clean worker from data structure - const workerIndex = this.workers.indexOf(worker) - this.workers.splice(workerIndex, 1) - this.tasks.delete(worker) - } - - /** - * Choose a worker for the next task. + * Chooses a worker for the next task. * - * The default implementation uses a round robin algorithm to distribute the load. + * The default uses a round robin algorithm to distribute the load. * - * @returns Worker. + * @returns [worker key, worker]. */ - protected chooseWorker (): Worker { - const chosenWorker = this.workers[this.nextWorkerIndex] - this.nextWorkerIndex = - this.workers.length - 1 === this.nextWorkerIndex - ? 0 - : this.nextWorkerIndex + 1 - return chosenWorker + protected chooseWorker (): [number, Worker] { + let workerKey: number + if ( + this.type === PoolType.DYNAMIC && + !this.full && + this.findFreeWorkerKey() === -1 + ) { + const createdWorker = this.createAndSetupWorker() + this.registerWorkerMessageListener(createdWorker, message => { + if ( + isKillBehavior(KillBehaviors.HARD, message.kill) || + (message.kill != null && + this.getWorkerTasksUsage(createdWorker)?.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) + } + }) + workerKey = this.getWorkerKey(createdWorker) + } else { + workerKey = this.workerChoiceStrategyContext.execute() + } + return [workerKey, this.workers[workerKey].worker] } /** - * Send a message to the given worker. + * Sends a message to the given worker. * - * @param worker The worker which should receive the message. - * @param message The message. + * @param worker - The worker which should receive the message. + * @param message - The message. */ protected abstract sendToWorker ( worker: Worker, message: MessageValue ): void + /** + * Registers a listener callback on a given worker. + * + * @param worker - The worker which should register a listener. + * @param listener - The message listener callback. + */ protected abstract registerWorkerMessageListener< Message extends Data | Response - > (worker: Worker, listener: (message: MessageValue) => void): void - - protected abstract unregisterWorkerMessageListener< - Message extends Data | Response - > (worker: Worker, listener: (message: MessageValue) => void): void - - protected internalExecute ( - worker: Worker, - messageId: number - ): Promise { - return new Promise((resolve, reject) => { - const listener: (message: MessageValue) => void = message => { - if (message.id === messageId) { - this.unregisterWorkerMessageListener(worker, listener) - this.decreaseWorkersTasks(worker) - if (message.error) reject(message.error) - else resolve(message.data as Response) - } - } - this.registerWorkerMessageListener(worker, listener) - }) - } + >(worker: Worker, listener: (message: MessageValue) => void): void /** * Returns a newly created worker. @@ -298,9 +348,10 @@ export abstract class AbstractPool< /** * Function that can be hooked up when a worker has been newly created and moved to the workers registry. * - * Can be used to update the `maxListeners` or binding the `main-worker`<->`worker` connection if not bind by default. + * Can be used to update the `maxListeners` or binding the `main-worker`\<-\>`worker` connection if not bind by default. * - * @param worker The newly created worker. + * @param worker - The newly created worker. + * @virtual */ protected abstract afterWorkerSetup (worker: Worker): void @@ -310,20 +361,132 @@ export abstract class AbstractPool< * @returns New, completely set up worker. */ protected createAndSetupWorker (): Worker { - const worker: Worker = this.createWorker() - - worker.on('error', this.opts.errorHandler ?? (() => {})) - worker.on('online', this.opts.onlineHandler ?? (() => {})) - worker.on('exit', this.opts.exitHandler ?? (() => {})) - worker.once('exit', () => this.removeWorker(worker)) - - this.workers.push(worker) + const worker = this.createWorker() + + worker.on('message', this.opts.messageHandler ?? EMPTY_FUNCTION) + worker.on('error', this.opts.errorHandler ?? EMPTY_FUNCTION) + worker.on('online', this.opts.onlineHandler ?? EMPTY_FUNCTION) + worker.on('exit', this.opts.exitHandler ?? EMPTY_FUNCTION) + worker.once('exit', () => { + this.removeWorker(worker) + }) - // Init tasks map - this.tasks.set(worker, 0) + this.pushWorker(worker, { + run: 0, + running: 0, + runTime: 0, + avgRunTime: 0, + error: 0 + }) this.afterWorkerSetup(worker) return worker } + + /** + * This function is the listener registered for each worker. + * + * @returns The listener function to execute when a message is received from a worker. + */ + protected workerListener (): (message: MessageValue) => void { + return message => { + if (message.id != null) { + // Task response received + const promiseResponse = this.promiseResponseMap.get(message.id) + if (promiseResponse != null) { + if (message.error != null) { + promiseResponse.reject(message.error) + } else { + promiseResponse.resolve(message.data as Response) + } + this.afterPromiseResponseHook(promiseResponse.worker, message) + this.promiseResponseMap.delete(message.id) + } + } + } + } + + private async internalExecute ( + workerKey: number, + worker: Worker, + messageId: string + ): Promise { + this.beforePromiseResponseHook(workerKey) + return await new Promise((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 checkAndEmitFull (): void { + if ( + this.type === PoolType.DYNAMIC && + this.opts.enableEvents === true && + this.full + ) { + this.emitter?.emit(PoolEvents.full) + } + } + + /** + * Gets the given worker tasks usage in the pool. + * + * @param worker - The worker. + * @returns The worker tasks usage. + */ + private getWorkerTasksUsage (worker: Worker): TasksUsage | undefined { + const workerKey = this.getWorkerKey(worker) + if (workerKey !== -1) { + return this.workers[workerKey].tasksUsage + } + throw new Error('Worker could not be found in the pool') + } + + /** + * Pushes the given worker in the pool. + * + * @param worker - The worker. + * @param tasksUsage - The worker tasks usage. + */ + private pushWorker (worker: Worker, tasksUsage: TasksUsage): void { + this.workers.push({ + worker, + tasksUsage + }) + } + + /** + * Sets the given worker in the pool. + * + * @param workerKey - The worker key. + * @param worker - The worker. + * @param tasksUsage - The worker tasks usage. + */ + private setWorker ( + workerKey: number, + worker: Worker, + tasksUsage: TasksUsage + ): void { + this.workers[workerKey] = { + worker, + tasksUsage + } + } + + /** + * Removes the given worker from the pool. + * + * @param worker - The worker that will be removed. + */ + protected removeWorker (worker: Worker): void { + const workerKey = this.getWorkerKey(worker) + this.workers.splice(workerKey, 1) + this.workerChoiceStrategyContext.remove(workerKey) + } }