cached-value.md

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new CachedValue(key, options)

This class lets you manage a specific value in the cache, preserving its type if you're using TypeScript:

import {CachedValue} from 'webext-storage-cache';

const url = new CachedValue('cached-url');

// Or in TypeScript
const url = new CachedValue<string>('cached-url');

Note: The name is unique but webext-storage-cache doesn't save you from bad usage. Avoid reusing the same key across the extension with different values, because it will cause conflicts:

const starNames = new CachedValue<string[]>('stars', {days: 1});
const starCount = new CachedValue<number>('stars'); // Bad: they will override each other

key

Type: string

The unique name that will be used in chrome.storage.local as cache:${key}

options

maxAge

Type: TimeDescriptor
Default: {days: 30}

The amount of time after which the cache item will expire after being each .set() call.

CachedValue#get()

Returns the cached value of key if it exists and hasn't expired, returns undefined otherwise.

const cache = new CachedValue('cached-url');
const url = await cache.get();
// It will be `undefined` if it's not found.

CachedValue#set(value)

Caches the value for the amount of time specified in the CachedValue constructor. It returns the value itself.

const cache = new CachedValue('core-info');
const info = await getInfoObject();
await cache.set(info); // Cached for 30 days by default

value

Type: string | number | boolean or array | object of those three types.

undefined will remove the cached item. For this purpose it's best to use CachedValue#delete() instead

CachedValue#isCached()

Checks whether the item is in the cache, returns a boolean.

const url = new CachedValue('url');
const isCached = await url.isCached();
// true or false

CachedValue.delete()

Deletes the requested item from the cache.

const url = new CachedValue('url');

await url.set('https://github.com');
console.log(await url.isCached()); // true

await url.delete();
console.log(await url.isCached()); // false

License

MIT © Federico Brigante