Lightweight and lazy cached function with TTL, negative TTL, and item limit controls.
npm install cached-fn
Lightweight and lazy cached function with TTL, negative TTL, and item limit controls.
``javascript
/**
* Simple cache system for fetching text (cache never expires)
*/
const fetchText = cachedFn(async (url) => {
const res = await fetch(url)
return res.text()
})
/**
* Singleton pattern (cache never expires)
*/
const getInstance = cachedFn(() => new MyClass())
/**
* Cached fetch for JSON with options:
* - cycle: results are scoped to 5-minute windows
* - cache is automatically invalidated every 5 minutes
*/
const fetchJson = cachedFn({cycle: 5 60 1000}, async (url) => {
const res = await fetch(url)
return res.json()
})
/**
* Cached fetch for ArrayBuffer with options:
* - maxItems: up to 100 cache entries
* - cache: cache expires after 60 seconds
* - negativeCache: failed results cached for 1 second
*/
const fetchBuffer = cachedFn({maxItems: 100, cache: 60 * 1000, negativeCache: 1000}, async (url) => {
const res = await fetch(url)
return res.arrayBuffer()
})
`
`javascript
const text = await fetchText(url)
const instance = getInstance()
const json = await fetchJson(url)
const buffer = await fetchBuffer(url)
`
`javascript``
process.on("SIGHUP", () => cachedFn.flush())
- https://www.npmjs.com/package/cached-fn
- https://github.com/kawanet/cached-fn
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