epic-cache

Simple nodejs caching module

Install

npm i epic-cache

Cache classes

Cache

The base abstract class extended by the other cache classes.

Only used to create other types of cache.

GenericCache

The main cache, it holds a map of <String, CacheType = any>

Create the instance

import { GenericCache } from 'epic-cache';
const cache = new GenericCache<CacheType>(options);

• CacheType: (default: any) Type of the elements you want to store in cache.
• options?: GenericCacheOptions

GenericCacheOptions

• maxSize: (default: 1000) max elements to store in cache

• sizeExceededStrategy: (default: no-cache) action to perform when an element is add to the cache when it's full.

  • no-cache: don't put the new element in the cache
  • throw-error: throw an error

• clearExpiredOnSizeExceeded: (default: true) clear all the expired keys before trying to an element to the cache when it's full

• defaultExpireTime: (default: 15m) default expire time assigned to elements add to cache without their own expireTime

  • The type of defaultExpireTime is Time | TimeString | number

Read more about the time classes

• expireOnInterval: (default: true) check and remove the expired keys every interval (the cache will always remove the expired keys when you try to get them regardless of this value)

• expireCheckInterval: (default: 10m) the time interval to check and remote expired keys

  • The type of expireCheckInterval is Time | TimeString | number

Read more about the time classes

Methods

Add an element

import { GenericCache, CacheElement } from 'epic-cache';
const cache = new GenericCache<number>();

// Add MattAge to the cache with value 31 with default expireTime of the cache
cache.set('MattAge', CacheElement.from(31));

// Add TaylorAge to the cache with value 22 with 10 seconds before expiration
cache.set('TaylorAge', CacheElement.from(22, '10s'));

// Note: you can also use the add function - The behavior is the exact same
cache.add('TaylorAge', CacheElement.from(22, '10s'))

Read more about the CacheElement class

Get an element

import { GenericCache, CacheElement } from 'epic-cache';
const cache = new GenericCache<number>();

cache.set('TaylorAge', CacheElement.from(22));

// Get the element from the cache
const taylorAge = cache.get('TaylorAge'); // 22

Delete an element

// TODO: Create the code

Events

// TODO: Create the code and the docs

CacheElement

// TODO: Create the code and the docs

Time classes

When you need to provide a time value you can use one of this three methods:

• TimeString type

import type { TimeString } from 'epic-cache';

const oneSecond: TimeString = '1s';
const fiveSeconds: TimeString = '5s';
const oneMinute: TimeString = '1m';
const oneHour: TimeString = '1h';

• number as milliseconds

const oneSecond = 1000;
const fiveSeconds = 1000 * 5;
const oneMinute = 1000 * 60;
const oneHour = 1000 * 60 * 60;

• Time class

import { Time } from 'epic-cache';

// You can pass a number or a TimeString as value
const oneSecond = new Time(1000);
const fiveSecond = new Time('5s');

// You can also use the static method from to create an instance
const oneMinute = Time.from(1000 * 60);
const oneHour = Time.from('1h');