import type { Worker } from 'cluster'
import type { MessagePort } from 'worker_threads'
import type { MessageValue } from '../utility-types'
-import type { WorkerOptions } from './worker-options'
-import { killBehaviorEnumeration } from './worker-options'
+import { EMPTY_FUNCTION } from '../utils'
+import type { KillBehavior, WorkerOptions } from './worker-options'
+import { KillBehaviors } from './worker-options'
-const defaultMaxInactiveTime = 1000 * 60
-const defaultKillBehavior = killBehaviorEnumeration.SOFT
+const DEFAULT_MAX_INACTIVE_TIME = 60000
+const DEFAULT_KILL_BEHAVIOR: KillBehavior = KillBehaviors.SOFT
/**
- * Base class containing some shared logic for all poolifier workers.
+ * Base class that implements some shared logic for all poolifier workers.
*
* @template MainWorker Type of main worker.
- * @template Data Type of data this worker receives from pool's execution.
- * @template Response Type of response the worker sends back to the main worker.
+ * @template Data Type of data this worker receives from pool's execution. This can only be serializable data.
+ * @template Response Type of response the worker sends back to the main worker. This can only be serializable data.
*/
export abstract class AbstractWorker<
MainWorker extends Worker | MessagePort,
Response = unknown
> extends AsyncResource {
/**
- * The maximum time to keep this worker alive while idle. The pool automatically checks and terminates this worker when the time expires.
- */
- protected readonly maxInactiveTime: number
- /**
- * The kill behavior set as option on the Worker constructor or a default value.
+ * Timestamp of the last task processed by this worker.
*/
- protected readonly killBehavior: string
+ protected lastTaskTimestamp: number
/**
- * Whether the worker is working asynchronously or not.
+ * Handler Id of the `aliveInterval` worker alive check.
*/
- protected readonly async: boolean
+ protected readonly aliveInterval?: NodeJS.Timeout
/**
- * Timestamp of the last task processed by this worker.
+ * Options for the worker.
*/
- protected lastTask: number
- /**
- * Handler ID of the `interval` alive check.
- */
- protected readonly interval?: NodeJS.Timeout
-
+ public readonly opts: WorkerOptions
/**
* Constructs a new poolifier worker.
*
type: string,
isMain: boolean,
fn: (data: Data) => Response,
- protected mainWorker?: MainWorker | null,
- public readonly opts: WorkerOptions = {
- killBehavior: defaultKillBehavior,
- maxInactiveTime: defaultMaxInactiveTime
+ protected mainWorker: MainWorker | undefined | null,
+ 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 pool automatically checks and terminates this worker when the time expires.
+ */
+ maxInactiveTime: DEFAULT_MAX_INACTIVE_TIME
}
) {
super(type)
- this.killBehavior = this.opts.killBehavior ?? defaultKillBehavior
- this.maxInactiveTime = this.opts.maxInactiveTime ?? defaultMaxInactiveTime
- this.async = !!this.opts.async
- this.lastTask = Date.now()
- if (!fn) throw new Error('fn parameter is mandatory')
+ this.opts = opts
+ this.checkFunctionInput(fn)
+ this.checkWorkerOptions(this.opts)
+ this.lastTaskTimestamp = Date.now()
// Keep the worker active
if (!isMain) {
- this.interval = setInterval(
+ this.aliveInterval = setInterval(
this.checkAlive.bind(this),
- this.maxInactiveTime / 2
+ (this.opts.maxInactiveTime ?? DEFAULT_MAX_INACTIVE_TIME) / 2
)
this.checkAlive.bind(this)()
}
this.mainWorker?.on('message', (value: MessageValue<Data, MainWorker>) => {
- if (value?.data && value.id) {
- // Here you will receive messages
- if (this.async) {
- this.runInAsyncScope(this.runAsync.bind(this), this, fn, value)
- } else {
- this.runInAsyncScope(this.run.bind(this), this, fn, value)
- }
- } else if (value.parent) {
- // Save a reference of the main worker to communicate with it
- // This will be received once
- this.mainWorker = value.parent
- } else if (value.kill) {
- // Here is time to kill this worker, just clearing the interval
- if (this.interval) clearInterval(this.interval)
- this.emitDestroy()
- }
+ this.messageListener(value, fn)
})
}
+ protected messageListener (
+ value: MessageValue<Data, MainWorker>,
+ fn: (data: Data) => Response
+ ): void {
+ if (value.data !== undefined && value.id !== undefined) {
+ // Here you will receive messages
+ if (this.opts.async === true) {
+ this.runInAsyncScope(this.runAsync.bind(this), this, fn, value)
+ } else {
+ this.runInAsyncScope(this.run.bind(this), this, fn, value)
+ }
+ } else if (value.parent !== undefined) {
+ // Save a reference of the main worker to communicate with it
+ // This will be received once
+ this.mainWorker = value.parent
+ } else if (value.kill !== undefined) {
+ // Here is time to kill this worker, just clearing the interval
+ if (this.aliveInterval != null) clearInterval(this.aliveInterval)
+ this.emitDestroy()
+ }
+ }
+
+ private checkWorkerOptions (opts: WorkerOptions): void {
+ this.opts.killBehavior = opts.killBehavior ?? DEFAULT_KILL_BEHAVIOR
+ this.opts.maxInactiveTime =
+ opts.maxInactiveTime ?? DEFAULT_MAX_INACTIVE_TIME
+ this.opts.async = opts.async ?? false
+ }
+
+ /**
+ * Checks if the `fn` parameter is passed to the constructor.
+ *
+ * @param fn The function that should be defined.
+ */
+ private checkFunctionInput (fn: (data: Data) => Response): void {
+ if (fn == null) throw new Error('fn parameter is mandatory')
+ if (typeof fn !== 'function') {
+ throw new TypeError('fn parameter is not a function')
+ }
+ }
+
/**
* Returns the main worker.
*
* @returns Reference to the main worker.
*/
protected getMainWorker (): MainWorker {
- if (!this.mainWorker) {
+ if (this.mainWorker == null) {
throw new Error('Main worker was not set')
}
return this.mainWorker
}
/**
- * Send a message to the main worker.
+ * Sends a message to the main worker.
*
* @param message The response message.
*/
protected abstract sendToMainWorker (message: MessageValue<Response>): void
/**
- * Check to see if the worker should be terminated, because its living too long.
+ * Checks if the worker should be terminated, because its living too long.
*/
protected checkAlive (): void {
- if (Date.now() - this.lastTask > this.maxInactiveTime) {
- this.sendToMainWorker({ kill: this.killBehavior })
+ if (
+ Date.now() - this.lastTaskTimestamp >
+ (this.opts.maxInactiveTime ?? DEFAULT_MAX_INACTIVE_TIME)
+ ) {
+ this.sendToMainWorker({ kill: this.opts.killBehavior })
}
}
/**
- * Handle an error and convert it to a string so it can be sent back to the main worker.
+ * 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 Message of the error.
*/
protected handleError (e: Error | string): string {
- return (e as unknown) as string
+ return e as string
}
/**
- * Run the given function synchronously.
+ * Runs the given function synchronously.
*
* @param fn Function that will be executed.
* @param value Input data for the given function.
value: MessageValue<Data>
): void {
try {
+ const startTaskTimestamp = Date.now()
const res = fn(value.data)
- this.sendToMainWorker({ data: res, id: value.id })
- this.lastTask = Date.now()
+ const taskRunTime = Date.now() - startTaskTimestamp
+ this.sendToMainWorker({ data: res, id: value.id, taskRunTime })
} catch (e) {
- const err = this.handleError(e)
+ const err = this.handleError(e as Error)
this.sendToMainWorker({ error: err, id: value.id })
- this.lastTask = Date.now()
+ } finally {
+ this.lastTaskTimestamp = Date.now()
}
}
/**
- * Run the given function asynchronously.
+ * Runs the given function asynchronously.
*
* @param fn Function that will be executed.
* @param value Input data for the given function.
fn: (data?: Data) => Promise<Response>,
value: MessageValue<Data>
): void {
+ const startTaskTimestamp = Date.now()
fn(value.data)
.then(res => {
- this.sendToMainWorker({ data: res, id: value.id })
- this.lastTask = Date.now()
+ const taskRunTime = Date.now() - startTaskTimestamp
+ this.sendToMainWorker({ data: res, id: value.id, taskRunTime })
return null
})
.catch(e => {
- const err = this.handleError(e)
+ const err = this.handleError(e as Error)
this.sendToMainWorker({ error: err, id: value.id })
- this.lastTask = Date.now()
})
+ .finally(() => {
+ this.lastTaskTimestamp = Date.now()
+ })
+ .catch(EMPTY_FUNCTION)
}
}