cached-call

Cached call

Cache the function result by wrapping it

Installation

npm i cached-call

Basic Usage

const CachedCall = require('cached-call')
const cache = new CachedCall()

cache({ someHeavyJob (v) { return v }, maxAge: 1000 })(v)

Options

const cache = new CachedCall()
cache({ [name]: func, maxAge, max, stale, key })(...args)

name	description	default	example
name	Function name for cache key	(required)
func	Cache target function	(required)
key	Key for create cache key (function or value)	(...args) => args	1, 'moo'
maxAge	Maximum age in ms	(required)	300, 100
args	Arguments that will be passed to key function	(required)
max	The maximum size of the cache	Infinity	1000, 100
stale	return the stale value before deleting it	false	true
cacheError	Cache error and rejection for ms	undefined	1000

Auto generated internal cache key by default

JSON.stringify([name, ...args])

Examples

Custom key function

Use only 3rd, 4th arguments for key

const key = (nan, fn, n1, n2) => [n1, n2]
const pickArgs = cache({ someFunction, key, maxAge: 100 })
pickArgs(NaN, () => {}, 1, 2) // cache key : ["someFunction", 1 ,2]

Clear cache at 10 or 20 minutes for every hour

const dayjs = require('dayjs')
const everyHour = min => () => dayjs().add(60 - min, 'm').startOf('m').minute(min) - Date.now()
const every10minutes = cache({ someFunction, maxAge: everyHour(10) })
const every20minutes = cache({ someFunction, maxAge: everyHour(20) })

Retry after 1s when error

const retryThrottle = cache({ someFunction, maxAge: 30000, cacheError: 1000 })
retryThrottle()

License

The MIT License (MIT)
Copyright (c) 2020 Elevista