map-age-cleaner

What is map-age-cleaner?

The map-age-cleaner npm package is designed to automatically remove expired items from a Map object in JavaScript based on a specified age. This is particularly useful for managing caches or temporary data storage where items should not persist indefinitely. The package works by wrapping a standard Map object and allowing the developer to specify a maximum age for the items. Once an item exceeds this age, it is automatically removed from the Map, helping to manage memory and data relevance efficiently.

What are map-age-cleaner's main functionalities?

Automatic cleanup of expired items

This feature allows for the automatic removal of items from a Map after they have been in the Map for a specified duration. The `maxAge` option is used to define how long (in milliseconds) an item should remain in the Map before being automatically removed.

const mapAgeCleaner = require('map-age-cleaner');
const myMap = new Map();
mapAgeCleaner(myMap, { maxAge: 10000 });
// Adds an item to the map
myMap.set('key', 'value');
// After 10 seconds, the item is automatically removed

Other packages similar to map-age-cleaner

lru-cache

lru-cache is a cache object that deletes the least-recently-used items. It offers similar functionality in terms of managing temporary data with automatic removal, but it bases removal on usage frequency rather than a fixed time duration. This makes it suitable for different scenarios where the access pattern rather than the age of the data determines its relevance.

node-cache

node-cache is a simple caching module with set, get and delete methods and it supports TTL (time to live) for entries. It provides functionality similar to map-age-cleaner by allowing entries to expire after a certain period. However, node-cache is a more comprehensive caching solution with additional features such as statistics about hits, misses, and keys stored.

README

map-age-cleaner

Automatically cleanup expired items in a Map

Install

$ npm install map-age-cleaner

Usage

import mapAgeCleaner from 'map-age-cleaner';

const map = new Map([
	['unicorn', {data: '🦄', maxAge: Date.now() + 1000}]
]);

mapAgeCleaner(map);

map.has('unicorn');
//=> true

// Wait for 1 second...

map.has('unicorn');
//=> false

Note: Items have to be ordered ascending based on the expiry property. This means that the item which will be expired first, should be in the first position of the Map.

API

mapAgeCleaner(map, [property])

Returns the Map instance.

map

Type: Map

Map instance which should be cleaned up.

property

Type: string
Default: maxAge

Name of the property which olds the expiry timestamp.

Related

• expiry-map - A Map implementation with expirable items
• expiry-set - A Set implementation with expirable keys
• mem - Memoize functions

License

MIT © Sam Verschueren