utils

JavaScript / TypeScript utils

Table of Contents

• utils
  • Table of Contents
  • Installation
  • Usage
    • cleanObject
    • reduceSeries
    • mapSeries
    • readdirRecursive
    • setPropertyRecursive
    • cursor
    • getFulfilledResult
    • msleep
    • kst
    • formatKst
    • filterOut
    • hashIndex
    • notEmpty
    • randomInt
    • safeSample
    • sample
  • License

Installation

$ npm i @well-balanced/utils
$ pnpm add @well-balanced/utils
$ yarn add @well-balanced/utils

Usage

cleanObject

If the object has fields with an undefined value, clean it.

example

const user = { id: 'id', name: 'name', age: 20, gender: undefined }
const cleaned = cleanObject(user) // { id: 'id', name: 'name', age: 20}

reduceSeries

Execute a function on each element of an array, sequentially.

example

import { reduceSeries } from '@well-balanced/utils'

const array = [1, 2, 3, 4, 5]
const sum = await reduceSeries(array, async (prev, curr) => prev + curr, 0)
console.log(sum) // 15

source

test

mapSeries

Map over an array, applying an asynchronous function sequentially.

example

import { mapSeries } from '@well-balanced/utils'

const array = [1, 2, 3, 4, 5]
const results = await mapSeries(array, async (item) => item * 2)

console.log(results) // [2, 4, 6, 8, 10]

source

test

readdirRecursive

Read a directory recursively and return a list of file paths.

example

import { readdirRecursive } from '@well-balanced/utils'

const files = await readdirRecursive('/path/to/directory')
console.log(files)

source

test

setPropertyRecursive

Set a nested property on an object, creating intermediate objects as necessary.

example

import { setPropertyRecursive } from '@well-balanced/utils'

const obj = { hello: 'world' }
const updated = setPropertyRecursive(
  ['key1', 'key2', 'key3'],
  'hello world',
  obj,
)

console.log(updated) // { key1: { key2: { key3: 'hello world' } }, hello: 'world' }

source

test

cursor

Encode and decode cursors for pagination.

example

import { encodeCursor, decodeCursor } from '@well-balanced/utils'

const obj = { page: 1, limit: 10 }
const cursor = encodeCursor(obj)
console.log(cursor) // Encoded cursor string

const decoded = decodeCursor(cursor)
console.log(decoded) // { page: 1, limit: 10 }

source

• encodeCursor
• decodeCursor

test

getFulfilledResult

Extract fulfilled results from an array of settled promises.

example

import { getFulfilledResult } from '@well-balanced/utils'

const promises = [
  Promise.resolve(1),
  Promise.reject(new Error('Failure')),
  Promise.resolve(3),
]

const settled = await Promise.allSettled(promises)
const results = getFulfilledResult(settled)

console.log(results) // [1, 3]

source

test

msleep

Sleep for a given number of milliseconds.

example

import { msleep } from '@well-balanced/utils'

await msleep(1000) // Sleep for 1 second
console.log('1 second later')

source

kst

Get the current date and time in Korea Standard Time.

example

import { kst } from '@well-balanced/utils'

const koreanTime = kst()
console.log(koreanTime)

formatKst

Format a date object to a string in Korea Standard Time.

example

import { formatKst } from '@well-balanced/utils'

const date = new Date()
const formattedDate = formatKst(date, 'yyyy-MM-dd HH:mm:ss')
console.log(formattedDate)

filterOut

Filter out elements from an array based on a comparator function.

example

import { filterOut } from '@well-balanced/utils'

const array = [1, 2, 3, 4, 5]
const valuesToRemove = [2, 4]
const comparator = (a: number, b: number) => a === b

const result = filterOut(array, valuesToRemove, comparator)
console.log(result) // [1, 3, 5]

hashIndex

Generate a hash index from a string.

example

import { hashIndex } from '@well-balanced/utils'

const index = hashIndex('example', 10)
console.log(index)

notEmpty

Check if a value is not null or undefined.

example

import { notEmpty } from '@well-balanced/utils'

const value = 'example'
if (notEmpty(value)) {
  console.log('Value is not empty')
}

randomInt

Generate a random integer between a given range.

example

import { randomInt } from '@well-balanced/utils'

const randomValue = randomInt(1, 10)
console.log(randomValue)

safeSample

Get a random element from an array excluding certain values.

example

import { safeSample } from '@well-balanced/utils'

const array = [1, 2, 3, 4, 5]
const valuesToExclude = [2, 4]
const comparator = (a: number, b: number) => a === b

const result = safeSample(array, valuesToExclude, comparator)
console.log(result)

sample

Get a random element from an array.

example

import { sample } from '@well-balanced/utils'

const array = [1, 2, 3, 4, 5]
const result = sample(array)
console.log(result)

License

MIT