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