memoizeConcurrent

memoize async functions such that concurrent calls return the same promise

Installation

npm i --save memoize-concurrent

Usage

Supports both ESM and CommonJS

// esm
import memo from 'memoize-concurrent'
// commonjs
const memo = require('memoize-concurrent').default

Basic Example

Example showing that concurrent calls return the same promise and asyncronous calls invoke the passed function

import memo from 'memoize-concurrent'

const memoizedFetch = memo(fetch)

const promise1 = memoizedFetch('http://localhost') // hits server
const promise2 = memoizedFetch('http://localhost') // hits cache
console.log(promise1 === promise2) // true
await promise1
const promise3 = memoizedFetch('http://localhost') // hits server
console.log(promise1 === promise3) // false

Uses mem for Memoization

memoizeConcurrent uses mem under the hood and supports the same options

import memo from 'memoize-concurrent'

const memoizedFetch = memo(fetch, {
  maxAge: 10, // maxAge of value in cache
  cacheKey: (args) => args[0], // function to compute cache key
  cache: new Map(), // provide your own cache
})

License

MIT