+import * as os from 'node:os'
+import { webcrypto } from 'node:crypto'
+import { Worker as ClusterWorker } from 'node:cluster'
+import { Worker as ThreadWorker } from 'node:worker_threads'
+import type {
+ MeasurementStatisticsRequirements,
+ WorkerChoiceStrategyOptions
+} from './pools/selection-strategies/selection-strategies-types'
+import type { KillBehavior } from './worker/worker-options'
+import { type IWorker, type WorkerType, WorkerTypes } from './pools/worker'
+
+/**
+ * Default task name.
+ */
+export const DEFAULT_TASK_NAME = 'default'
+
/**
* An intentional empty function.
*/
export const EMPTY_FUNCTION: () => void = Object.freeze(() => {
/* Intentionally empty */
})
+
+/**
+ * Default worker choice strategy options.
+ */
+export const DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS: WorkerChoiceStrategyOptions =
+ {
+ retries: 6,
+ runTime: { median: false },
+ waitTime: { median: false },
+ elu: { median: false }
+ }
+
+/**
+ * Default measurement statistics requirements.
+ */
+export const DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS: MeasurementStatisticsRequirements =
+ {
+ aggregate: false,
+ average: false,
+ median: false
+ }
+
+/**
+ * Returns safe host OS optimized estimate of the default amount of parallelism a pool should use.
+ * Always returns a value greater than zero.
+ *
+ * @returns The host OS optimized maximum pool size.
+ */
+export const availableParallelism = (): number => {
+ let availableParallelism = 1
+ try {
+ availableParallelism = os.availableParallelism()
+ } catch {
+ const cpus = os.cpus()
+ if (Array.isArray(cpus) && cpus.length > 0) {
+ availableParallelism = cpus.length
+ }
+ }
+ return availableParallelism
+}
+
+/**
+ * Returns the worker type of the given worker.
+ *
+ * @param worker - The worker to get the type of.
+ * @returns The worker type of the given worker.
+ * @internal
+ */
+export const getWorkerType = (worker: IWorker): WorkerType | undefined => {
+ if (worker instanceof ThreadWorker) {
+ return WorkerTypes.thread
+ } else if (worker instanceof ClusterWorker) {
+ return WorkerTypes.cluster
+ }
+}
+
+/**
+ * Returns the worker id of the given worker.
+ *
+ * @param worker - The worker to get the id of.
+ * @returns The worker id of the given worker.
+ * @internal
+ */
+export const getWorkerId = (worker: IWorker): number | undefined => {
+ if (worker instanceof ThreadWorker) {
+ return worker.threadId
+ } else if (worker instanceof ClusterWorker) {
+ return worker.id
+ }
+}
+
+/**
+ * Sleeps for the given amount of milliseconds.
+ *
+ * @param ms - The amount of milliseconds to sleep.
+ * @returns A promise that resolves after the given amount of milliseconds.
+ * @internal
+ */
+export const sleep = async (ms: number): Promise<void> => {
+ await new Promise(resolve => {
+ setTimeout(resolve, ms)
+ })
+}
+
+/**
+ * Computes the retry delay in milliseconds using an exponential back off algorithm.
+ *
+ * @param retryNumber - The number of retries that have already been attempted
+ * @param delayFactor - The base delay factor in milliseconds
+ * @returns Delay in milliseconds
+ * @internal
+ */
+export const exponentialDelay = (
+ retryNumber = 0,
+ delayFactor = 100
+): number => {
+ const delay = Math.pow(2, retryNumber) * delayFactor
+ const randomSum = delay * 0.2 * secureRandom() // 0-20% of the delay
+ return delay + randomSum
+}
+
+/**
+ * Computes the average of the given data set.
+ *
+ * @param dataSet - Data set.
+ * @returns The average of the given data set.
+ * @internal
+ */
+export const average = (dataSet: number[]): number => {
+ if (Array.isArray(dataSet) && dataSet.length === 0) {
+ return 0
+ }
+ if (Array.isArray(dataSet) && dataSet.length === 1) {
+ return dataSet[0]
+ }
+ return (
+ dataSet.reduce((accumulator, number) => accumulator + number, 0) /
+ dataSet.length
+ )
+}
+
+/**
+ * Computes the median of the given data set.
+ *
+ * @param dataSet - Data set.
+ * @returns The median of the given data set.
+ * @internal
+ */
+export const median = (dataSet: number[]): number => {
+ if (Array.isArray(dataSet) && dataSet.length === 0) {
+ return 0
+ }
+ if (Array.isArray(dataSet) && dataSet.length === 1) {
+ return dataSet[0]
+ }
+ const sortedDataSet = dataSet.slice().sort((a, b) => a - b)
+ return (
+ (sortedDataSet[(sortedDataSet.length - 1) >> 1] +
+ sortedDataSet[sortedDataSet.length >> 1]) /
+ 2
+ )
+}
+
+/**
+ * Rounds the given number to the given scale.
+ * The rounding is done using the "round half away from zero" method.
+ *
+ * @param num - The number to round.
+ * @param scale - The scale to round to.
+ * @returns The rounded number.
+ * @internal
+ */
+export const round = (num: number, scale = 2): number => {
+ const rounder = Math.pow(10, scale)
+ return Math.round(num * rounder * (1 + Number.EPSILON)) / rounder
+}
+
+/**
+ * Is the given object a plain object?
+ *
+ * @param obj - The object to check.
+ * @returns `true` if the given object is a plain object, `false` otherwise.
+ * @internal
+ */
+export const isPlainObject = (obj: unknown): boolean =>
+ typeof obj === 'object' &&
+ obj !== null &&
+ obj?.constructor === Object &&
+ Object.prototype.toString.call(obj) === '[object Object]'
+
+/**
+ * Detects whether the given value is a kill behavior or not.
+ *
+ * @typeParam KB - Which specific KillBehavior type to test against.
+ * @param killBehavior - Which kind of kill behavior to detect.
+ * @param value - Any value.
+ * @returns `true` if `value` was strictly equals to `killBehavior`, otherwise `false`.
+ * @internal
+ */
+export const isKillBehavior = <KB extends KillBehavior>(
+ killBehavior: KB,
+ value: unknown
+): value is KB => {
+ return value === killBehavior
+}
+
+/**
+ * Detects whether the given value is an asynchronous function or not.
+ *
+ * @param fn - Any value.
+ * @returns `true` if `fn` was an asynchronous function, otherwise `false`.
+ * @internal
+ */
+export const isAsyncFunction = (
+ fn: unknown
+): fn is (...args: unknown[]) => Promise<unknown> => {
+ return typeof fn === 'function' && fn.constructor.name === 'AsyncFunction'
+}
+
+/**
+ * Generates a cryptographically secure random number in the [0,1[ range
+ *
+ * @returns A number in the [0,1[ range
+ * @internal
+ */
+export const secureRandom = (): number => {
+ return webcrypto.getRandomValues(new Uint32Array(1))[0] / 0x100000000
+}
+
+/**
+ * Returns the minimum of the given numbers.
+ * If no numbers are given, `Infinity` is returned.
+ *
+ * @param args - The numbers to get the minimum of.
+ * @returns The minimum of the given numbers.
+ * @internal
+ */
+export const min = (...args: number[]): number =>
+ args.reduce((minimum, num) => (minimum < num ? minimum : num), Infinity)
+
+/**
+ * Returns the maximum of the given numbers.
+ * If no numbers are given, `-Infinity` is returned.
+ *
+ * @param args - The numbers to get the maximum of.
+ * @returns The maximum of the given numbers.
+ * @internal
+ */
+export const max = (...args: number[]): number =>
+ args.reduce((maximum, num) => (maximum > num ? maximum : num), -Infinity)
repositories / poolifier.git / blobdiff