X-Git-Url: https://git.piment-noir.org/?a=blobdiff_plain;f=src%2Futils.ts;h=c568a29a049eda2de26cf9bd99d63e613294bc3f;hb=5bbdaeff9b95f2ecb177394f869e9d0715e38e9e;hp=80e6b9f3b5473dee9e5547930f05ce8b6b473631;hpb=2845f2a5555247bbc4e5f6f1059d4f95405a49cd;p=poolifier.git diff --git a/src/utils.ts b/src/utils.ts index 80e6b9f3..c568a29a 100644 --- a/src/utils.ts +++ b/src/utils.ts @@ -1,36 +1,19 @@ -import { cpus, availableParallelism as parallelism } from 'node:os' -import type { - MeasurementStatisticsRequirements, - WorkerChoiceStrategyOptions -} from './pools/selection-strategies/selection-strategies-types' -import type { KillBehavior } from './worker/worker-options' +import { getRandomValues } from 'node:crypto' +import * as os from 'node:os' -/** - * An intentional empty function. - */ -export const EMPTY_FUNCTION: () => void = Object.freeze(() => { - /* Intentionally empty */ -}) +import type { KillBehavior } from './worker/worker-options.js' /** - * Default worker choice strategy options. + * Default task name. */ -export const DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS: WorkerChoiceStrategyOptions = - { - runTime: { median: false }, - waitTime: { median: false }, - elu: { median: false } - } +export const DEFAULT_TASK_NAME = 'default' /** - * Default measurement statistics requirements. + * An intentional empty function. */ -export const DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS: MeasurementStatisticsRequirements = - { - aggregate: false, - average: false, - median: false - } +export const EMPTY_FUNCTION: () => void = Object.freeze(() => { + /* Intentionally empty */ +}) /** * Returns safe host OS optimized estimate of the default amount of parallelism a pool should use. @@ -41,27 +24,76 @@ export const DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS: MeasurementStatisticsR export const availableParallelism = (): number => { let availableParallelism = 1 try { - availableParallelism = parallelism() + availableParallelism = os.availableParallelism() } catch { - const numberOfCpus = cpus() - if (Array.isArray(numberOfCpus) && numberOfCpus.length > 0) { - availableParallelism = numberOfCpus.length + const cpus = os.cpus() + if (Array.isArray(cpus) && cpus.length > 0) { + availableParallelism = cpus.length } } return availableParallelism } +/** + * 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 => { + 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 + } else 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) { + } else if (Array.isArray(dataSet) && dataSet.length === 1) { return dataSet[0] } const sortedDataSet = dataSet.slice().sort((a, b) => a - b) @@ -79,6 +111,7 @@ export const median = (dataSet: number[]): number => { * @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) @@ -86,24 +119,26 @@ export const round = (num: number, scale = 2): number => { } /** - * Is the given object a plain object? + * Is the given value a plain object? * - * @param obj - The object to check. - * @returns `true` if the given object is a plain object, `false` otherwise. + * @param value - The value to check. + * @returns `true` if the given value 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]' +export const isPlainObject = (value: unknown): value is object => + typeof value === 'object' && + value !== null && + value.constructor === Object && + Object.prototype.toString.call(value) === '[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. + * @param value - Unknown value. * @returns `true` if `value` was strictly equals to `killBehavior`, otherwise `false`. + * @internal */ export const isKillBehavior = ( killBehavior: KB, @@ -115,11 +150,73 @@ export const isKillBehavior = ( /** * Detects whether the given value is an asynchronous function or not. * - * @param fn - Any value. + * @param fn - Unknown value. * @returns `true` if `fn` was an asynchronous function, otherwise `false`. + * @internal */ export const isAsyncFunction = ( fn: unknown ): fn is (...args: unknown[]) => Promise => { 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 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) + +/** + * Wraps a function so that it can only be called once. + * + * @param fn - The function to wrap. + * @param context - The context to bind the function to. + * @returns The wrapped function. + * + * @typeParam A - The function's arguments. + * @typeParam R - The function's return value. + * @typeParam C - The function's context. + * @internal + */ +// eslint-disable-next-line @typescript-eslint/no-explicit-any +export const once = ( + fn: (...args: A) => R, + context: C +): ((...args: A) => R) => { + let result: R + return (...args: A) => { + // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition + if (fn != null) { + result = fn.apply(context, args) + ;(fn as unknown as undefined) = (context as unknown as undefined) = + undefined + } + return result + } +}