import { performance } from 'node:perf_hooks'
import type {
MessageValue,
+ Task,
TaskPerformance,
WorkerStatistics
} from '../utility-types'
-import { EMPTY_FUNCTION, isPlainObject } from '../utils'
+import {
+ DEFAULT_TASK_NAME,
+ EMPTY_FUNCTION,
+ isAsyncFunction,
+ isPlainObject
+} from '../utils'
import {
type KillBehavior,
KillBehaviors,
type WorkerOptions
} from './worker-options'
import type {
+ TaskAsyncFunction,
+ TaskFunction,
TaskFunctions,
- WorkerAsyncFunction,
- WorkerFunction,
- WorkerSyncFunction
-} from './worker-functions'
+ TaskSyncFunction
+} from './task-functions'
-const DEFAULT_FUNCTION_NAME = 'default'
const DEFAULT_MAX_INACTIVE_TIME = 60000
const DEFAULT_KILL_BEHAVIOR: KillBehavior = KillBehaviors.SOFT
* Base class that implements some shared logic for all poolifier workers.
*
* @typeParam MainWorker - Type of main worker.
- * @typeParam Data - Type of data this worker receives from pool's execution. This can only be serializable data.
- * @typeParam Response - Type of response the worker sends back to the main worker. This can only be serializable data.
+ * @typeParam Data - Type of data this worker receives from pool's execution. This can only be structured-cloneable data.
+ * @typeParam Response - Type of response the worker sends back to the main worker. This can only be structured-cloneable data.
*/
export abstract class AbstractWorker<
MainWorker extends Worker | MessagePort,
Data = unknown,
Response = unknown
> extends AsyncResource {
+ /**
+ * Worker id.
+ */
+ protected abstract id: number
/**
* Task function(s) processed by the worker when the pool's `execution` function is invoked.
*/
- protected taskFunctions!: Map<string, WorkerFunction<Data, Response>>
+ protected taskFunctions!: Map<string, TaskFunction<Data, Response>>
/**
* Timestamp of the last task processed by this worker.
*/
protected lastTaskTimestamp!: number
/**
- * Performance statistics computation.
+ * Performance statistics computation requirements.
*/
protected statistics!: WorkerStatistics
/**
- * Handler id of the `aliveInterval` worker alive check.
+ * Handler id of the `activeInterval` worker activity check.
*/
- protected readonly aliveInterval?: NodeJS.Timeout
+ protected activeInterval?: NodeJS.Timeout
/**
* Constructs a new poolifier worker.
*
* @param type - The type of async event.
* @param isMain - Whether this is the main worker or not.
- * @param taskFunctions - Task function(s) processed by the worker when the pool's `execution` function is invoked. The first function is the default function.
* @param mainWorker - Reference to main worker.
+ * @param taskFunctions - Task function(s) processed by the worker when the pool's `execution` function is invoked. The first function is the default function.
* @param opts - Options for the worker.
*/
public constructor (
type: string,
protected readonly isMain: boolean,
- taskFunctions:
- | WorkerFunction<Data, Response>
- | TaskFunctions<Data, Response>,
- protected mainWorker: MainWorker | undefined | null,
+ private readonly mainWorker: MainWorker,
+ taskFunctions: TaskFunction<Data, Response> | TaskFunctions<Data, Response>,
protected readonly opts: WorkerOptions = {
/**
* The kill behavior option on this worker or its default value.
*/
killBehavior: DEFAULT_KILL_BEHAVIOR,
/**
- * The maximum time to keep this worker alive while idle.
+ * The maximum time to keep this worker active while idle.
* The pool automatically checks and terminates this worker when the time expires.
*/
maxInactiveTime: DEFAULT_MAX_INACTIVE_TIME
this.checkWorkerOptions(this.opts)
this.checkTaskFunctions(taskFunctions)
if (!this.isMain) {
- this.lastTaskTimestamp = performance.now()
- this.aliveInterval = setInterval(
- this.checkAlive.bind(this),
- (this.opts.maxInactiveTime ?? DEFAULT_MAX_INACTIVE_TIME) / 2
- )
- this.checkAlive.bind(this)()
+ this.getMainWorker()?.on('message', this.handleReadyMessage.bind(this))
}
- this.mainWorker?.on('message', this.messageListener.bind(this))
}
private checkWorkerOptions (opts: WorkerOptions): void {
* @param taskFunctions - The task function(s) parameter that should be checked.
*/
private checkTaskFunctions (
- taskFunctions:
- | WorkerFunction<Data, Response>
- | TaskFunctions<Data, Response>
+ taskFunctions: TaskFunction<Data, Response> | TaskFunctions<Data, Response>
): void {
if (taskFunctions == null) {
throw new Error('taskFunctions parameter is mandatory')
}
- this.taskFunctions = new Map<string, WorkerFunction<Data, Response>>()
+ this.taskFunctions = new Map<string, TaskFunction<Data, Response>>()
if (typeof taskFunctions === 'function') {
- this.taskFunctions.set(DEFAULT_FUNCTION_NAME, taskFunctions.bind(this))
+ const boundFn = taskFunctions.bind(this)
+ this.taskFunctions.set(DEFAULT_TASK_NAME, boundFn)
+ this.taskFunctions.set(
+ typeof taskFunctions.name === 'string' &&
+ taskFunctions.name.trim().length > 0
+ ? taskFunctions.name
+ : 'fn1',
+ boundFn
+ )
} else if (isPlainObject(taskFunctions)) {
let firstEntry = true
for (const [name, fn] of Object.entries(taskFunctions)) {
+ if (typeof name !== 'string') {
+ throw new TypeError(
+ 'A taskFunctions parameter object key is not a string'
+ )
+ }
if (typeof fn !== 'function') {
throw new TypeError(
'A taskFunctions parameter object value is not a function'
)
}
- this.taskFunctions.set(name, fn.bind(this))
+ const boundFn = fn.bind(this)
if (firstEntry) {
- this.taskFunctions.set(DEFAULT_FUNCTION_NAME, fn.bind(this))
+ this.taskFunctions.set(DEFAULT_TASK_NAME, boundFn)
firstEntry = false
}
+ this.taskFunctions.set(name, boundFn)
}
if (firstEntry) {
throw new Error('taskFunctions parameter object is empty')
}
}
+ /**
+ * Checks if the worker has a task function with the given name.
+ *
+ * @param name - The name of the task function to check.
+ * @returns Whether the worker has a task function with the given name or not.
+ * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `name` parameter is not a string.
+ */
+ public hasTaskFunction (name: string): boolean {
+ if (typeof name !== 'string') {
+ throw new TypeError('name parameter is not a string')
+ }
+ return this.taskFunctions.has(name)
+ }
+
+ /**
+ * Adds a task function to the worker.
+ * If a task function with the same name already exists, it is replaced.
+ *
+ * @param name - The name of the task function to add.
+ * @param fn - The task function to add.
+ * @returns Whether the task function was added or not.
+ * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `name` parameter is not a string.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the `name` parameter is the default task function reserved name.
+ * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `fn` parameter is not a function.
+ */
+ public addTaskFunction (
+ name: string,
+ fn: TaskFunction<Data, Response>
+ ): boolean {
+ if (typeof name !== 'string') {
+ throw new TypeError('name parameter is not a string')
+ }
+ if (name === DEFAULT_TASK_NAME) {
+ throw new Error(
+ 'Cannot add a task function with the default reserved name'
+ )
+ }
+ if (typeof fn !== 'function') {
+ throw new TypeError('fn parameter is not a function')
+ }
+ try {
+ const boundFn = fn.bind(this)
+ if (
+ this.taskFunctions.get(name) ===
+ this.taskFunctions.get(DEFAULT_TASK_NAME)
+ ) {
+ this.taskFunctions.set(DEFAULT_TASK_NAME, boundFn)
+ }
+ this.taskFunctions.set(name, boundFn)
+ return true
+ } catch {
+ return false
+ }
+ }
+
+ /**
+ * Removes a task function from the worker.
+ *
+ * @param name - The name of the task function to remove.
+ * @returns Whether the task function existed and was removed or not.
+ * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `name` parameter is not a string.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the `name` parameter is the default task function reserved name.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the `name` parameter is the task function used as default task function.
+ */
+ public removeTaskFunction (name: string): boolean {
+ if (typeof name !== 'string') {
+ throw new TypeError('name parameter is not a string')
+ }
+ if (name === DEFAULT_TASK_NAME) {
+ throw new Error(
+ 'Cannot remove the task function with the default reserved name'
+ )
+ }
+ if (
+ this.taskFunctions.get(name) === this.taskFunctions.get(DEFAULT_TASK_NAME)
+ ) {
+ throw new Error(
+ 'Cannot remove the task function used as the default task function'
+ )
+ }
+ return this.taskFunctions.delete(name)
+ }
+
+ /**
+ * Lists the names of the worker's task functions.
+ *
+ * @returns The names of the worker's task functions.
+ */
+ public listTaskFunctions (): string[] {
+ return Array.from(this.taskFunctions.keys())
+ }
+
+ /**
+ * Sets the default task function to use in the worker.
+ *
+ * @param name - The name of the task function to use as default task function.
+ * @returns Whether the default task function was set or not.
+ * @throws {@link https://nodejs.org/api/errors.html#class-typeerror} If the `name` parameter is not a string.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the `name` parameter is the default task function reserved name.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the `name` parameter is a non-existing task function.
+ */
+ public setDefaultTaskFunction (name: string): boolean {
+ if (typeof name !== 'string') {
+ throw new TypeError('name parameter is not a string')
+ }
+ if (name === DEFAULT_TASK_NAME) {
+ throw new Error(
+ 'Cannot set the default task function reserved name as the default task function'
+ )
+ }
+ if (!this.taskFunctions.has(name)) {
+ throw new Error(
+ 'Cannot set the default task function to a non-existing task function'
+ )
+ }
+ try {
+ this.taskFunctions.set(
+ DEFAULT_TASK_NAME,
+ this.taskFunctions.get(name) as TaskFunction<Data, Response>
+ )
+ return true
+ } catch {
+ return false
+ }
+ }
+
+ /**
+ * Handles the ready message sent by the main worker.
+ *
+ * @param message - The ready message.
+ */
+ protected abstract handleReadyMessage (message: MessageValue<Data>): void
+
/**
* Worker message listener.
*
- * @param message - Message received.
+ * @param message - The received message.
*/
- protected messageListener (
- message: MessageValue<Data, Data, MainWorker>
- ): void {
- if (message.id != null && message.data != null) {
- // Task message received
- const fn = this.getTaskFunction(message.name)
- if (fn?.constructor.name === 'AsyncFunction') {
- this.runInAsyncScope(this.runAsync.bind(this), this, fn, message)
- } else {
- this.runInAsyncScope(this.runSync.bind(this), this, fn, message)
+ protected messageListener (message: MessageValue<Data>): void {
+ if (message.workerId === this.id) {
+ if (message.statistics != null) {
+ // Statistics message received
+ this.statistics = message.statistics
+ } else if (message.checkActive != null) {
+ // Check active message received
+ !this.isMain && message.checkActive
+ ? this.startCheckActive()
+ : this.stopCheckActive()
+ } else if (message.id != null && message.data != null) {
+ // Task message received
+ this.run(message)
+ } else if (message.kill === true) {
+ // Kill message received
+ this.handleKillMessage(message)
}
- } else if (message.parent != null) {
- // Main worker reference message received
- this.mainWorker = message.parent
- } else if (message.kill != null) {
- // Kill message received
- this.aliveInterval != null && clearInterval(this.aliveInterval)
- this.emitDestroy()
- } else if (message.statistics != null) {
- // Statistics message received
- this.statistics = message.statistics
+ }
+ }
+
+ /**
+ * Handles a kill message sent by the main worker.
+ *
+ * @param message - The kill message.
+ */
+ protected handleKillMessage (message: MessageValue<Data>): void {
+ !this.isMain && this.stopCheckActive()
+ this.emitDestroy()
+ }
+
+ /**
+ * Starts the worker check active interval.
+ */
+ private startCheckActive (): void {
+ this.lastTaskTimestamp = performance.now()
+ this.activeInterval = setInterval(
+ this.checkActive.bind(this),
+ (this.opts.maxInactiveTime ?? DEFAULT_MAX_INACTIVE_TIME) / 2
+ )
+ }
+
+ /**
+ * Stops the worker check active interval.
+ */
+ private stopCheckActive (): void {
+ if (this.activeInterval != null) {
+ clearInterval(this.activeInterval)
+ delete this.activeInterval
+ }
+ }
+
+ /**
+ * Checks if the worker should be terminated, because its living too long.
+ */
+ private checkActive (): void {
+ if (
+ performance.now() - this.lastTaskTimestamp >
+ (this.opts.maxInactiveTime ?? DEFAULT_MAX_INACTIVE_TIME)
+ ) {
+ this.sendToMainWorker({ kill: this.opts.killBehavior, workerId: this.id })
}
}
*/
protected getMainWorker (): MainWorker {
if (this.mainWorker == null) {
- throw new Error('Main worker was not set')
+ throw new Error('Main worker not set')
}
return this.mainWorker
}
/**
- * Sends a message to the main worker.
+ * Sends a message to main worker.
*
* @param message - The response message.
*/
): void
/**
- * Checks if the worker should be terminated, because its living too long.
+ * Handles an error and convert it to a string so it can be sent back to the main worker.
+ *
+ * @param e - The error raised by the worker.
+ * @returns The error message.
*/
- protected checkAlive (): void {
- if (
- performance.now() - this.lastTaskTimestamp >
- (this.opts.maxInactiveTime ?? DEFAULT_MAX_INACTIVE_TIME)
- ) {
- this.sendToMainWorker({ kill: this.opts.killBehavior })
- }
+ protected handleError (e: Error | string): string {
+ return e instanceof Error ? e.message : e
}
/**
- * Handles an error and convert it to a string so it can be sent back to the main worker.
+ * Runs the given task.
*
- * @param e - The error raised by the worker.
- * @returns Message of the error.
+ * @param task - The task to execute.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the task function is not found.
*/
- protected handleError (e: Error | string): string {
- return e as string
+ protected run (task: Task<Data>): void {
+ if (this.isMain) {
+ throw new Error('Cannot run a task in the main worker')
+ }
+ const fn = this.getTaskFunction(task.name)
+ if (isAsyncFunction(fn)) {
+ this.runInAsyncScope(this.runAsync.bind(this), this, fn, task)
+ } else {
+ this.runInAsyncScope(this.runSync.bind(this), this, fn, task)
+ }
}
/**
- * Runs the given function synchronously.
+ * Runs the given task function synchronously.
*
- * @param fn - Function that will be executed.
- * @param message - Input data for the given function.
+ * @param fn - Task function that will be executed.
+ * @param task - Input data for the task function.
*/
protected runSync (
- fn: WorkerSyncFunction<Data, Response>,
- message: MessageValue<Data>
+ fn: TaskSyncFunction<Data, Response>,
+ task: Task<Data>
): void {
try {
- let taskPerformance = this.beginTaskPerformance()
- const res = fn(message.data)
+ let taskPerformance = this.beginTaskPerformance(task.name)
+ const res = fn(task.data)
taskPerformance = this.endTaskPerformance(taskPerformance)
this.sendToMainWorker({
data: res,
taskPerformance,
- id: message.id
+ workerId: this.id,
+ id: task.id
})
} catch (e) {
- const err = this.handleError(e as Error)
+ const errorMessage = this.handleError(e as Error | string)
this.sendToMainWorker({
taskError: {
- message: err,
- data: message.data
+ name: task.name ?? DEFAULT_TASK_NAME,
+ message: errorMessage,
+ data: task.data
},
- id: message.id
+ workerId: this.id,
+ id: task.id
})
} finally {
- !this.isMain && (this.lastTaskTimestamp = performance.now())
+ this.updateLastTaskTimestamp()
}
}
/**
- * Runs the given function asynchronously.
+ * Runs the given task function asynchronously.
*
- * @param fn - Function that will be executed.
- * @param message - Input data for the given function.
+ * @param fn - Task function that will be executed.
+ * @param task - Input data for the task function.
*/
protected runAsync (
- fn: WorkerAsyncFunction<Data, Response>,
- message: MessageValue<Data>
+ fn: TaskAsyncFunction<Data, Response>,
+ task: Task<Data>
): void {
- let taskPerformance = this.beginTaskPerformance()
- fn(message.data)
+ let taskPerformance = this.beginTaskPerformance(task.name)
+ fn(task.data)
.then(res => {
taskPerformance = this.endTaskPerformance(taskPerformance)
this.sendToMainWorker({
data: res,
taskPerformance,
- id: message.id
+ workerId: this.id,
+ id: task.id
})
return null
})
.catch(e => {
- const err = this.handleError(e as Error)
+ const errorMessage = this.handleError(e as Error | string)
this.sendToMainWorker({
taskError: {
- message: err,
- data: message.data
+ name: task.name ?? DEFAULT_TASK_NAME,
+ message: errorMessage,
+ data: task.data
},
- id: message.id
+ workerId: this.id,
+ id: task.id
})
})
.finally(() => {
- !this.isMain && (this.lastTaskTimestamp = performance.now())
+ this.updateLastTaskTimestamp()
})
.catch(EMPTY_FUNCTION)
}
/**
- * Gets the task function in the given scope.
+ * Gets the task function with the given name.
*
- * @param name - Name of the function that will be returned.
+ * @param name - Name of the task function that will be returned.
+ * @returns The task function.
+ * @throws {@link https://nodejs.org/api/errors.html#class-error} If the task function is not found.
*/
- private getTaskFunction (name?: string): WorkerFunction<Data, Response> {
- name = name ?? DEFAULT_FUNCTION_NAME
+ private getTaskFunction (name?: string): TaskFunction<Data, Response> {
+ name = name ?? DEFAULT_TASK_NAME
const fn = this.taskFunctions.get(name)
if (fn == null) {
throw new Error(`Task function '${name}' not found`)
return fn
}
- private beginTaskPerformance (): TaskPerformance {
+ private beginTaskPerformance (name?: string): TaskPerformance {
+ this.checkStatistics()
return {
+ name: name ?? DEFAULT_TASK_NAME,
timestamp: performance.now(),
...(this.statistics.elu && { elu: performance.eventLoopUtilization() })
}
private endTaskPerformance (
taskPerformance: TaskPerformance
): TaskPerformance {
+ this.checkStatistics()
return {
...taskPerformance,
...(this.statistics.runTime && {
})
}
}
+
+ private checkStatistics (): void {
+ if (this.statistics == null) {
+ throw new Error('Performance statistics computation requirements not set')
+ }
+ }
+
+ private updateLastTaskTimestamp (): void {
+ if (!this.isMain && this.activeInterval != null) {
+ this.lastTaskTimestamp = performance.now()
+ }
+ }
}