core/cache/decorators/ttl

This module provides a wrapper for Cache data structures to add a feature of the cache expiring. To describe how long should keep an item in the cache, use the ttl parameter. The value for ttl should be provided in milliseconds.

Example

import addTTL from 'core/cache/decorators/ttl';
import SimpleCache from 'core/cache/simple';

const
  cache = addTTL(new SimpleCache());

cache.add('foo', 'bar1', {ttl: 500});
cache.add('foo2', 'bar2', {ttl: 1000});
cache.add('baz', 'bar3');

console.log(cache.keys().length); // 3

setTimeout(() => {
  console.log(cache.keys().length); // 1
}, 2000);

Default ttl

When you wrap a cache object with the ttl decorator, you can provide the default ttl value. This value is used when you don't provide the ttl parameter when saving an item.

import addTTL from 'core/cache/decorators/ttl';
import SimpleCache from 'core/cache/simple';

const
  cache = addTTL(new SimpleCache(), 10000);

cache.add('foo', 'bar1', {ttl: 500}); // TTL 500 has the higher priority and will overwrite 10000s
cache.add('foo2', 'bar2'); // TTL will be 10000

Property collisions

In case of a property collision, all old properties, including their TTL values, will be overwritten.

import addTTL from 'core/cache/decorators/ttl';
import SimpleCache from 'core/cache/simple';

const
  cache = addTTL(new SimpleCache());

cache.add('foo', 'bar1', {ttl: 500});
cache.add('foo', 'bar1'); // TTL will be overwritten